Recent investigations of biopolymer membrane and applications.
Membranes prepared from oceanic biopolymers have a high potential in membrane separation processes and water purification. It is anticipated to result in more biocompatible and lower-cost materials compared with artificial polymers. This chapter describes the excellent performance of oceanic biopolymer membranes in separation engineering and the regulation factors controlling membrane properties. In particular, chitosan and alginate were picked up as intelligent membrane materials to provide the promised molecular size recognition and other membrane properties. Future prospective strategies for a simple methodology for preparing stable membranes from oceanic biopolymers and the development of selective separation processing were reviewed.
- oceanic biopolymer
- mechanical strength
- mass transfer characteristics
1.1. Overview of oceanic biopolymers in membrane separation technology
Membrane separation technology has been applied in various fields, such as the chemical industry, food production, pharmaceutical products, environmental sciences, and water purification, because it can be operated without heating and residual toxicity. Its energy cost was lower than conventional thermal separation technologies [1–4]. It can be employed for broad components by selecting optimum membranes.
Development of oceanic biopolymer membranes such as chitosan and alginate has exponentially increased due to increases in the demand for biocompatibility, environment adaptability, renewability, and selective separation ability [5–6]. In the field of membrane science, most membranes have been made from petroleum-based polymers used as raw materials for the membrane body. Petroleum-based synthetic polymers such as polyethylene, polyamide, polyimide, and polysulfonate have been used as the main materials of the membrane body for a long time. The practical use of biopolymer membranes was less than synthetic polymer membranes, because controlling the physical and chemical properties of a biopolymer produced from natural bioresources was difficult in practical membrane applications. Cellulose-based membranes have been extensively used in practical applications since the development of the anisotropic cellulose acetate membrane in 1963 by Loeb and Sourirajan . Applications of biopolymer materials have increased recently for membrane sciences . Recent studies of biopolymer membranes are summarized in Table 1 referred to previous literatures [9-22]. In the past five years, oceanic biopolymers have attracted attention for their chemical functional ability. Investigations of oceanic biopolymer membranes, especially chitosan and alginate, for various applications have drastically increased.
The common aim of membrane separation technology is to separate a target component from a mixture with the aid of permeation through the membrane, while rejecting other components. The key characteristics for practical use are as follows: mechanical strength, permeation flux, diffusivity of molecule, and micro-/nanostructure. This chapter describes the dominant factors in controlling important properties for practical membrane separation applications for oceanic polymer membrane, especially those of chitosan and alginate.
2. Chitosan membrane
Chitosan is a well-known sustainable and biocompatible oceanic biomaterial. It has been attracted in creating new polymer materials for broad application due to its nontoxicity, biocompatibility, and biodegradability . Chitosan is refined by removing an acetyl group from chitin, which is mainly produced in oceanic bioresources such as the shells of crabs and shrimps. Chitin is the second most abundant natural polymer in nature, after cellulose . Chitosan is generally discarded as industrial waste around the world . It is strongly expected to be useful as a biocompatible and reactive material for making functional gel membranes. Recent studies of various chitosan membranes are summarized in Table 2 and Table 3 referred to previous literatures [5-6, 12, 15-19, 24-46].
2.1. Chemical composition and membrane formation
Chitosan is a heteropolymer obtained by alkaline deacetylation of chitin at the C-2 position as shown in Figure 1 (a) and (b). Chitosan is generally defined by a deacetylation degree (
The beneficial effects of chitosan are as a dietary fiber, such as its inhibition of fat digestibility  and its reduction of cholesterols . The biodegradability and biocompatibility of chitosan are also suitable for biomedical applications .
Chitosan is dissolved in an acid aqueous solution, such as acetic acid. To form a water-insoluble chitosan membrane, the acetic acid has to be neutralized by basic components. The authors have reported preparation of chitosan membrane using casting methods . For example, 4 g of chitosan was dissolved in 198 mL of 1.7 mol･L–1 acetic acid aqueous solution. The solution was mixed magnetically for 12 h at room temperature to obtain a mature solution. Some insoluble matter was removed by vacuum filtration using a filter paper (Grade No. 1, ADVANTEC, Japan). The concentration of the chitosan casting solution was 0.02 g-chitosan･mL-chitosan casting solution–1. Ten grams of the casting solution was dispensed in a glass Petri dish (inner diameter 7.75 cm) and dried in a thermostatic chamber at 333 K for 24 h. A dried chitosan membrane formed on the glass Petri dish. A 20 mL of sodium hydroxide (NaOH) aqueous solution was directly introduced onto the dried chitosan membrane. The chitosan membrane was continuously immersed for 3 h in NaOH solution for neutralization. The concentration of the supplied NaOH ranged from 0.1 to 5 mol･L–1. In this case, the stoichiometric equivalent concentration of NaOH was estimated to be 0.83 mol･L–1. After neutralization, the swollen membrane was easily separated from the glass Petri dish and was washed fully with pure water to remove excess NaOH.
2.2. Dominant role of the acid–base neutralization in chitosan membrane characteristics
The authors previously reported the dominant role of the acid–base neutralization process in forming chitosan membranes for controlling some membrane properties .
2.2.1. Mechanical strength
The mechanical strength, maximum tensile stress (Figure 2a), and maximum strain (Figure 2b) at membrane rupture presented bell-shaped curves with peaks when the NaOH concentration increased. For an 81%
2.2.2. Water permeation flux
Figure 3 demonstrates that the water permeation flux and the volumetric void fraction of the swollen membrane were almost linearly correlated. The NaOH concentration in the neutralization process enhanced both the water permeation flux and the void fraction in the membrane. Neutralization using a high NaOH concentration weakens hydrogen bonding between chitosan polymer chains. The void fraction in the swollen membrane can assumed to be the volume of a water permeation channel occupying the membrane. This result suggests that the membrane structure involving water permeation was dominantly regulated by the NaOH concentration during neutralization.
2.2.3. Mass transfer characteristics
The effective diffusion coefficient of the model components was evaluated based on the mass transfer flux. The membrane was sandwiched between twin mass transfer cells. The feed solution contained the model components (urea 60 Da, Methyl Orange 327 Da, Rose Bengal 1017 Da, and Sirius Red 1373 Da) at the desired concentrations, and the stripping solution was deionized water. The overall mass transfer coefficient
The overall mass transfer coefficient
The aqueous phases in the mass transfer cells were sufficiently stirred to attain a fully developed turbulent condition (
The initial membrane thickness in the swollen state (
Figure 4 depicts the change in the effective diffusion coefficient in the chitosan membrane with the molecular weight of the tested components for 81%
The effective diffusion coefficient of a membrane prepared from 5 mol･L–1 NaOH greatly increased relative to a membrane prepared from 1 mol･L–1. The molecular diffusion channel formed by the polymer networks became enlarged due to the higher NaOH concentration employed.
The dominant role of the acid–base neutralization process in chitosan membranes was revealed to control membrane properties involving mechanical strength, the water permeation flux, and the effective diffusion coefficient.
2.2.4. Morphology of chitosan membrane
Figure 5 presents scanning probe microscope (SPM) photographs of chitosan membrane surfaces. The chitosan membrane made from 1 mol･L–1 NaOH had a very smooth surface. In contrast, the membrane made from 5 mol･L–1 NaOH had a somewhat rough surface.
2.3. Other regulation factors
2.3.1. Deacetylation degree
The deacetylation degree (
Increasing the deacetylation degree enhances the surface hydrophilicity of the membrane surface because the acetamido groups on the chitosan membrane are converted into amino groups. This advances the effective formation of hydrogen bonds between the amino and hydroxyl groups and between the amino groups in the chitosan molecules, thus resulting in a dense molecular chain in the membrane .
2.3.2. Molecular weights of chitosan
Chitosan membranes prepared by Uragami and coworkers from different molecular weights (13–201 kDa) were tested during pervaporation dehydration of an ethanol aqueous solution. The permeation flux decreased with increasing molecular weight from 13 kDa to 90 kDa, then increased from 90 kDa to 201 kDa. In contrast, the water permeation selectivity from the ethanol aqueous solution increased remarkably with increasing molecular weight up to 90 kDa. Over 90 kDa, the selectivity decreased. These results were understood to indicate that the 90 kDa molecular weight effectively formed entanglements and thus produced the strongest hydrogen bonds between the molecular chains of chitosan , although the mechanical strength increased with increasing average molecular weight of chitosan .
2.3.3. Addition of a cross-linker
Basically, chitosan can be formed into an insoluble membrane by acid–base neutralization in the casting solution without using a cross-linker. However, the addition of a cross-linker to improve membrane characteristics was carefully investigated.
The most prominent effect of an additive cross-linker is improved mechanical strength. Figure 6 depicts the change of mechanical strength of chitosan membrane (maximum stress vs. maximum strain at membrane rupture) with increasing amount of cross-linker. In a common trend, increasing the amount of cross-linker forms a rigid membrane. The addition of genipin as a cross-linker increased the maximum stress and reduced the maximum strain at membrane rupture . Increasing added amounts of glutaraldehyde, methanol with ethylene glycol diglycidyl ether, and gallic acid also increased the mechanical strength. However, excess addition of cross-linker formed rigid and fragile structures on the chitosan membrane [25–26, 53].
Other researchers have reported that cross-linking with sodium tripolyphosphate enhanced the mechanical strength of chitosan membrane . From another viewpoint, Shenvi and coworkers determined the effect of the pH value of the cross-linking solution on the membrane properties. A chitosan membrane cross-linked by tripolyphosphate solution at pH 5 realized a higher rejection rate of NaCl and MgSO4 than a membrane cross-linked at pH 9 .
The enhancement of pervaporative dehydration ability of water–alcohol mixtures by adding cross-linker has been frequently reported . A chitosan membrane cross-linked with toluene-2,4-diisocyanate exhibited high pervaporative dehydration ability with an isopropanol aqueous solution in which the selectivity of water
2.3.4. Hybrid approaches with other materials
Some hybrid approaches using chitosan and other materials have been proposed to overcome problems in practical use . To make a porous structure on a chitosan membrane, SiO2, a porogen agent, was mixed with chitosan cast solution and removed from the membrane. The average pore size reached a maximum of 8.5 μm when the mixing ratio of chitosan and SiO2 was 1:2 .
Chitosan membranes are frequently combined with nanomaterial to form a composite medium. A chitosan membrane composited with a multi-walled carbon nanotube was modified by adding perfluorooctanesulfonyl fluoride (PFOSF). The added PFOSF enhanced antibacterial activity due to its remarkable hydrophobicity. The mechanical strength increased with increasing multi-walled carbon nanotubes . Chitosan composited with ZnO nanoparticles was also investigated for antibacterial activity . Chitosan membrane has a good potential as a composited nanomaterial medium for biologically based nanotechnology.
2.3.5. Chemical modification of the chitosan molecular chain
Chitosan has great potential for chemical modification. Functionalized chitosan is often used as the main membrane body, coating agent, or additive agent for functionalization of surface modifications. Graphene oxide functionalizing a chitosan membrane as a surface modification agent on a commercial polyamide membrane has been investigated. The water flux and NaCl rejection of the chitosan membrane were increased by the modification, due to the formation of a dense, thin layer of graphene-oxide-functionalized chitosan, which is better than natural chitosan membrane . Kumar and coworkers prepared various chitosan membranes: a natural chitosan blended with polysulfone membrane, an
3. Alginate membrane
Alginate is abundantly and sustainably produced by marine biological resources, especially brown seaweed. It has been widely applied in the food industry  and as a thickener , a suspending agent , an emulsion stabilizer , a gelling agent , and a film-forming agent . In addition, alginate was continuously developed as useful materials for biomedical applications, especially for controlled delivery of drugs and other biologically active compounds and for the encapsulation of cells . In recent pioneering works, alginate has developed as membrane material with excellent molecular selectivity for water-soluble components . Recent studies of various alginate membranes are listed in Table 4 and Table 5 referred to previous literatures [10-11, 15, 22, 66-95].
3.1. Chemical composition and membrane formation of alginate
The molecular chain of alginate is constructed of a block copolymer of β-D-mannuronate (Figure 7a) and α-L-guluronate (Figure 7b) . These two uronates construct a polymeric block in an alginate polymer chain with the following three types of block: homopolymeric blocks of α-L-guluronate (GG blocks), blocks with an alternating sequence in varying proportions of guluronate and mannuronate (MG blocks), and homopolymeric blocks of β-D-mannuronate (MM blocks) . GG blocks chelate alkaline earth-metal ions because of the spatial arrangement of the pyranose ring and the hydroxyl oxygen atoms, and thus create a much stronger interaction than MM blocks and MG blocks [98–99].
Sodium alginate easily forms a cross-link with the presence of divalent cations such as Ca2+, resulting in a highly compacted and dense gel network. GG blocks are constructed mainly of a cross-linked zone with Ca2+. This is called an “Egg-box junction” (Figure 7c), where the ions were assimilated to “Eggs” .
Sodium alginate forms a cross-link in the presence of divalent cations such as Ca2+, resulting in a highly compacted gel network. Homopolymeric blocks of α-L-guluronate are constructed mainly of a cross-linked zone with divalent cations. This section describes the impact of this kind of divalent cations and the mass fraction of homopolymeric blocks of α-L-guluronate in an alginate polymer chain (
The authors previously reported the preparation of alginate membrane described below [10–11]. A 20 mL sodium alginate aqueous solution (10 g･L–1) was placed in a Petri dish. The solution was gradually dried at a mild temperature in a desiccator (298 K) or an electrical dryer (303 K) for 24 h to prevent heat degradation. A dried, thin film of sodium alginate was obtained on the Petri dish.
An electrolyte aqueous solution (CaCl2, SrCl2, and BaCl2) was directly introduced onto the dried, thin sodium alginate film as a source of divalent cation for cross-linking. The concentration range of the electrolyte aqueous solutions was 0.1–1.0 mol･L–1. A stable alginate membrane was quickly formed in the Petri dish at room temperature. After 20 min, the prepared swollen membrane was spontaneously separated from the surface of the Petri dish. The membrane remained in the electrolyte aqueous solution for further 20 min. The membrane was totally immersed in the electrolyte aqueous solution for 40 min. The prepared membrane was repeatedly washed with pure water to remove excess electrolyte, and then stored in pure water.
3.2. Effect of homopolymeric block of α-L-guluronate (
The authors previously reported that membrane properties are evidently controlled by the mass fraction (
The mass of the GG block (
3.2.1. Mechanical strength
The effect of
3.2.2. Mass transfer characteristics
An alginate membrane performs superior molecular size recognition on low-molecular-weight components from 60 Da to 600Da . Figure 9 demonstrates that the effective diffusion coefficient in the membrane (
The effect of
3.2.3. Morphology of the alginate membrane
Figure 11 presents SPM photographs of the calcium alginate membrane surface. The distribution of membrane asperity clearly decays with increasing
3.3. Effect of cross-linking divalent cations
The authors prepared a stable alginate membrane cross-linked with CaCl2, SrCl2, and BaCl2
3.3.1. Water permeability
The water permeation coefficient was evaluated based on the pure water permeation flux as presented in Figure 12. It was decreased logarithmically with increasing concentration of cross-linker. This suggests that the number of permeation channels and/or the size of the permeation channels decreased with increasing concentration of cross-linking ions. The effect of cross-linker concentration on water permeability appeared strongly in the BaCl2 used, suggesting that Ba2+ structures have a much stronger interaction in α-L-guluronate block. Binding of divalent cation to the three kind of copolymer blocks have been investigated [106–107]. The following orders of binding strength indicated by sign of equality were reported:
Hence, the alginate membrane cross-linked with BaCl2 constructed a dense polymer network due to strong bonding between alginate molecular chain and Ba2+.
3.3.2. Volumetric water fraction
The volumetric water content of a swollen membrane can be assumed to an indicator of the void fraction of the membrane structure . Figure 13 illustrates the effect of the concentration of electrolyte solution on the void fraction of the membrane. The void fraction decreased with increasing concentration of the cross-linking electrolyte solution. An alginate membrane cross-linked with BaCl2 was highly densified by the provided Ba2+.
3.4. Other regulation factors for controlling membrane properties
3.4.1. Addition of cross-linker other than metal ions
Conventional cross-linkers forming a polymer membrane were also examined to realize the alginate membrane. Glutaraldehyde is most commonly employed as a cross-linker to form sodium alginate membranes [83–84]. These membranes cross-linked with glutaraldehyde were developed for use in organic dehydration by pervaporation [66, 79, 82]. A sodium alginate membrane cross-linked with phosphoric acid was prepared for pervaporative dehydration of ethanol aqueous solution . This resulted in 3.5 × 10–2 kg･m–2･h–1 of permeation flux and 2182 of selectivity as defined by Eq. (4). A sodium alginate membrane cross-linked by sodium tartrate was characterized by CO2 capture from CO2/N2 .
3.4.2. Hybrids with other polymers or materials
Many efforts have been made to enhance the performance of the alginate membrane by blending it with different hydrophilic polymers. An alginate-blended DNA membrane cross-linked with Mg2+ or Ca2+ was investigated with regard to the permeation flux of ethanol aqueous solution for pervaporation . The permeation flux and selectivity of a calcium alginate membrane with DNA in pervaporative dehydration for an ethanol aqueous solution were measured as 1.2×10–2 kg･m–2･h–1 and 5500, respectively. In contrast, a magnesium alginate membrane with DNA exhibited a permeation flux and selectivity of 1.2×10–2 kg･m–2･h–1 and 6500.
Hybrid membranes of sodium alginate and dextrin cross-linked with glutaraldehyde had a permeation flux of 9.65 × 10–2 kg･m–2･h–1 permeation flux and a selectivity of 8991 in pervaporative dehydration for an isopropanol aqueous solution .
Alginate membranes are frequently combined with nanomaterials to form a composite medium. A calcium alginate membrane containing multi-walled carbon nanotubes was prepared as a new nanofiltration membrane. It had high mechanical strength, antifouling ability, and high rejection of small organic molecules (Congo Red, 697Da) .
Strategic regulation of an oceanic biopolymer membrane to control its characteristics in membrane separation technology was demonstrated. An oceanic biopolymer chitosan membrane can be easily prepared by casting chitosan in dilute aqueous organic acids and neutralizing it with an alkaline aqueous solution. The dominant role of neutralization for chitosan membrane involves the mechanical strength, the permeation flux, and the mass transfer characteristics. Other regulating factors, such as the deacetylation degree, the average molecular weight, and the addition of a cross-linker were presented.
A calcium alginate membrane performs superior molecular size recognition on low-molecular-weight components from 60 Da to 600 Da due to a dense polymer network consisting of homopolymeric blocks of α-L-guluronate and calcium ions. The kind of cross-linking ion used is also able to control the membrane properties. Barium ion performed a stronger cross-linker in the alginate membrane rather than Ca2+ and Sr2+, and a highly complex structure was formed. The mass fraction of homopolymeric blocks of α-L-guluronate and cross-linking metal ions were impact factors in regulating the mass transfer characteristics, water permeability, and mechanical strength.
These oceanic polymers are biodegradable, biocompatible, environmentally friendly, stable, and easily available from renewable agricultural resources. In the future, oceanic biopolymer membranes should be developed as an alternative to artificial polymer membranes.
Xiong B, Richard T L, Kumar M. Integrated acidogenic digestion and carboxylic acid separation by nanofiltration membranes for the lignocellulosic carboxylate platform. J. Membrane Science. 2015;489: 275–283. DOI: 10.1016/j.memsci.2015.04.022
Xiao T, Wang P, Yang X, Cai X, Lu J. Fabrication and characterization of novel asymmetric polyvinylidene fluoride (PVDF) membranes by the nonsolvent thermally induced phase separation (NTIPS) method for membrane distillation applications. J. Membrane Science. 2015;489: 160–174.DOI: 10.1016/j.memsci.2015.03.081
Sawada S, Ursino C, Galiano F, Simone S, Drioli E, Figoli A. Effect of citrate-based non-toxic solvents on poly (vinylidene fluoride) membrane preparation via thermally induced phase separation. J. Membrane Science. 2015;493: 232–242. DOI: 10.1016/j.memsci.2015.07.003
Baker R W. Membrane Technology and Applications. 3rd ed. Chichester: John Wiley & Sons Ltd; 2012. 575p. DOI: 10.1002/9781118359686
Ma B, Qin A, Li X, Zhao X, He C. Structure and properties of chitin whisker reinforced chitosan membranes. International J. Biological Macromolecules. 2014;64: 341–346. DOI:10.1016/j.ijbiomac.2013.12.015
Bueno C Z., Dias A M A, de Sousa H J C, Braga M E M, Moraes A M. Control of the properties of porous chitosan-alginate membranes through the addition of different proportions of Pluronic F68. Materials Science and Engineering C 2014;44: 117–125. DOI: 10.1016/j.msec.2014.08.014
Loeb S, Sourirajan S. Sea water demineralization by means of an osmotic membrane. In: Advances in Chemistry. Vol. 38.America: ACS Publications; 1963. p. 117–132. DOI: 10.1021/ba-1963-0038.ch009
Wu P, Imai M. Novel biopolymer composite membrane involved with selective mass transfer and excellent water permeability. In: Ning R Y, editor. Advancing Desalination. Croatia: InTech; 2012. p. 57–81. DOI: 10.5772/50697
Torres F G, Troncoso O P, Piaggio F, Hijar A. Structure–property relationships of a biopolymer network: The eggshell membrane. Acta Biomaterialia. 2010;6: 3687–3693. DOI: 10.1016/j.actbio.2010.03.014
Kashima K, Imai M, Suzuki I. Superior molecular size screening and mass-transfer characterization of calcium alginate membrane. Desalination and Water Treatment. 2010;17: 143–149. DOI: 10.5004/dwt.2010.1710
Kashima K, Imai M. Dominant impact of the α-L-guluronic acid chain on regulation of the mass transfer character of calcium alginate membranes. Desalination and Water Treatment. 2011;34: 257–265. DOI: 10.5004/dwt.2011.2892
Michalak I, Mucha M. The release of active substances from selected carbohydrate biopolymer membranes. Carbohydrate Polymers. 2012;87: 2432–2438. DOI: 10.1016/j.carbpol.2011.11.013
Wu P, Imai M. Excellent dyes removal and remarkable molecular size rejection of novel biopolymer composite membrane. Desalination and Water Treatment. 2013;51: 5237–5247. DOI: 10.1080/19443994.2013.768836
Lakra R, Saranya R, Lukka Thuyavan Y, Sugashini S, Meera K M, Begum S, Arthanareeswaran G. Separation of acetic acid and reducing sugars from biomass derived hydrosylate using biopolymer blend polyethersulfone membrane. Separation and Purification Technology. 2013;118: 853–861. DOI: 10.1016/j.seppur.2013.08.023
Moraes M A, Cocenza D S, Vasconcellos F da C, Fraceto L F, Beppu M M. Chitosan and alginate biopolymer membranes for remediation of contaminated water with herbicides. J. Environmental Management. 2013;131: 222–227. DOI: 10.1016/j.jenvman.2013.09.028
Nomoto R, Imai M. Dominant role of acid-base neutralization process in forming chitosan membrane for regulating mechanical strength and mass transfer characteristics. J. Chitin and Chitosan Science. 2014;2: 197–204. DOI: 10.1166/jcc.2014.1055
Ma S, Chen Z, Qiao F, Sun Y, Yang X, Deng X, Cen L, Cai Q, Wu M, Zhang X, Gao P. Guided bone regeneration with tripolyphosphate cross-linked asymmetric chitosan membrane. J. Dentistry. 2014;42: 1603–1612. DOI: 10.1016/j.jdent.2014.08.015
Uragami T, Saito T, Miyata T. Pervaporative dehydration characteristics of an ethanol/water azeotrope through various chitosan membranes. Carbohydrate Polymers. 2015;120: 1–6. DOI: 10.1016/j.carbpol.2014.11.032
Alias S S, Ariff Z M, Mohamad A A. Porous membrane based on chitosan–SiO2 for coin cell proton battery. Ceramics International. 2015;41: 5484–5491. DOI: 10.1016/j.ceramint.2014.12.119
Puspasari T, Pradeep N, Peinemann K-V. Crosslinked cellulose thin film composite nanofiltration membranes with zero salt rejection. J. Membrane Science 2015;491: 132–137. DOI: 10.1016/j.memsci.2015.05.002
Livazovic S, Li Z, Behzad A R, Peinemann K-V, Nunes S P. Cellulose multilayer membranes manufacture with ionic liquid. J. Membrane Science. 2015;490: 282–293. DOI: 10.1016/j.memsci.2015.05.009
Zhang X, Lin B, Zhao K, Wei J, Guo J., Cui W, Jiang S, Liu D, Li J. A free-standing calcium alginate/polyacrylamide hydrogel nanofiltration membrane with high anti-fouling performance: Preparation and characterization. Desalination. 2015:365: 234–241. DOI: 10.1016/j.desal.2015.03.015
Patel A K. Chitosan: Emergence as potent candidate for green adhesive market. Biochemical Engineering J..2015; 102: 74–81. DOI: 10.1016/j.bej.2015.01.005
Bai H, Zhang H, He Y, Liu J, Zhang B, Wang J. Enhanced proton conduction of chitosan membrane enabled by halloysite nanotubes bearing sulfonate polyelectrolyte brushes. J. Membrane Science. 2014;454: 220–232. DOI: 10.1016/j.memsci.2013.12.005
Tasselli F, Mirmohseni A, Seyed Dorraji M S, Figoli A. Mechanical, swelling and adsorptive properties of dry–wet spun chitosan hollow fibers crosslinked with glutaraldehyde. Reactive and Functional Polymers. 2013;73: 218–223. DOI: 10.1016/j.reactfunctpolym.2012.08.007
Sun X, Wang Z, Kadouh H, Zhou K, The antimicrobial, mechanical, physical and structural properties of chitosan–gallic acid films. LWT - Food Science and Technology. 2014;57: 83–89. DOI: 10.1016/j.lwt.2013.11.037
Wanichapichart P, Bootluck W, Thopan P, Yu L D. Influence of nitrogen ion implantation on filtration of fluoride and cadmium using polysulfone/chitosan blend membranes. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms. 2014;326: 195–199. DOI: 10.1016/j.nimb.2013.10.091
Shenvi S, Ismail A F, Isloor A M. Preparation and characterization study of PPEES/chitosan composite membrane crosslinked with tripolyphosphate. Desalination. 2014;344: 90–96. DOI: 10.1016/j.desal.2014.02.026
Han F, Dong Y, Song A, Yin R, Li S. Alginate/chitosan based bi-layer composite membrane as potential sustained-release wound dressing containing ciprofloxacin hydrochloride. Applied Surface Science. 2014;311: 626–634. DOI: 10.1016/j.apsusc.2014.05.125
Karim Z, Mathew A P, Grahn M, Mouzon J, Oksman K. Nanoporous membranes with cellulose nanocrystals as functional entity in chitosan: Removal of dyes from water. Carbohydrate Polymers. 2014;112: 668–676. DOI: 10.1016/j.carbpol.2014.06.048
Dudek G, Gnus M, Turczyn R, Strzelewicz A, Krasowska M. Pervaporation with chitosan membranes containing iron oxide nanoparticles. Separation and Purification Technology. 2014;133: 8–15. DOI: 10.1016/j.seppur.2014.06.032
Kumar R, Isloor A M, Ismail A F. Preparation and evaluation of heavy metal rejection properties of polysulfone/chitosan, polysulfone/N-succinyl chitosan and polysulfone/N-propylphosphonyl chitosan blend ultrafiltration membranes. Desalination. 2014;350: 102–108. DOI: 10.1016/j.desal.2014.07.010
Sajjan A M, Premakshi H G, Kariduraganavar M Y. Synthesis and characterization of GTMAC grafted chitosan membranes for the dehydration of low water content isopropanol by pervaporation. J. Industrial and Engineering Chemistry. 2015;25: 151–161. DOI: 10.1016/j.jiec.2014.10.027
Bibi S, Yasin T, Hassan S, Riaz M, Nawaz M. Chitosan/CNTs green nanocomposite membrane: Synthesis, swelling and polyaromatic hydrocarbons removal. Materials Science and Engineering C. 2015;46: 359–365. DOI: 10.1016/j.msec.2014.10.057
Ji Y-L, An Q-F, Zhao F-Y, Gao C-J. Fabrication of chitosan/PDMCHEA blend positively charged membranes with improved mechanical properties and high nanofiltration performances. Desalination. 2015;357: 8–15. DOI: 10.1016/j.desal.2014.11.005
Premakshi H G, Ramesh K, Kariduraganavar M Y. Modification of crosslinked chitosan membrane using NaY zeolite for pervaporation separation of water–isopropanol mixtures. Chemical Engineering Research and Design. 2015;94: 32–43. DOI: 10.1016/j.cherd.2014.11.014
Santamaria M, Pecoraro C M, Quarto F D, Bocchetta P. Chitosan–phosphotungstic acid complex as membranes for low temperature H2–O2 fuel cell. J. Power Sources. 2015;276: 189–194. DOI: 10.1016/j.jpowsour.2014.11.147
Zhu J, Tian M, Zhang Y, Zhang H, Liu J. Fabrication of a novel “loose” nanofiltration membrane by facile blending with Chitosan–Montmorillonite nanosheets for dyes purification. Chemical Engineering J.. 2015;265: 184–193. DOI: 10.1016/j.cej.2014.12.054
Li Y-H, Cheng C-Y, Wang N-K, Tan H-Y, Tsai Y-J, Hsiao C-H, Ma D H-K, Yeh L-K. Characterization of the modified chitosan membrane cross-linked with genipin for the cultured corneal epithelial cells. Colloids and Surfaces B: Biointerfaces. 2015;126: 237–244. DOI: 10.1016/j.colsurfb.2014.12.029
Hegab H M, Wimalasiri Y, Ginic-Markovic M, Zou L. Improving the fouling resistance of brackish water membranes via surface modification with graphene oxide functionalized chitosan. Desalination. 2015;365: 99–107. DOI: 10.1016/j.desal.2015.02.029
Zhang D, Zhou W, Wei B, Wang X, Tang R, Nie J, Wang J. Carboxyl-modified poly (vinyl alcohol)-crosslinked chitosan hydrogel films for potential wound dressing. Carbohydrate Polymers. 2015;125: 189–199. DOI: 10.1016/j.carbpol.2015.02.034
Panda S R, Mukherjee M, De S. Preparation, characterization and humic acid removal capacity of chitosan coated iron-oxide-polyacrylonitrile mixed matrix membrane. J. Water Process Engineering. 2015;6: 93–104. DOI: 10.1016/j.jwpe.2015.03.007
Antunes B P, Moreira A F, Gaspar V M, Correia I J. Chitosan/arginine–chitosan polymer blends for assembly of nanofibrous membranes for wound regeneration. Carbohydrate Polymers. 2015;130: 104–112. DOI: 10.1016/j.carbpol.2015.04.072
Song K, Gao A, Cheng X, Xie K. Preparation of the superhydrophobic nano-hybrid membrane containing carbon nanotube based on chitosan and its antibacterial activity. Carbohydrate Polymers. 2015;130: 381–387. DOI:10.1016/j.carbpol.2015.05.023
Wang J, He R. Formation and evaluation of interpenetrating networks of anion exchange membranes based on quaternized chitosan and copolymer poly (acrylamide)/polystyrene. Solid State Ionics. 2015;278: 49–57. DOI: 10.1016/j.ssi.2015.05.017
Malini M, Thirumavalavan M, Yang W-Y, Lee J-F, Annadurai G. A versatile chitosan/ZnO nanocomposite with enhanced antimicrobial properties. International Journal of Biological Macromolecules. 2015;80: 121–129. DOI: 10.1016/j.ijbiomac.2015.06.036
Deuchi K, Kanauchi O, Imasato Y, Kobayashi E. Decreasing effect of chitosan on the apparent fat digestibility by rats fed on high-fat diet. Bioscience, Biotechnology, and biochemistry. 1994;58: 1613–1616. DOI: 10.1271/bbb.58.1613
Yao H-T, Huang S-Y, Chiang M-T. A comparative study on hypoglycemic and hypocholesterolemic effects of high and low molecular weight chitosan in streptozotocin-induced diabetic rats. Food and Chemical Toxicology. 2008;46: 1525–1534. DOI: 10.1016/j.fct.2007.12.012
Lu G, Kong L, Sheng B, Wang G, Gong Y, Zhang X. Degradation of covalently cross-linked carboxymethyl chitosan and its potential application for peripheral nerve regeneration. European Polymer J.. 2007;43: 3807–3818. DOI: 10.1016/j.eurpolymj.2007.06.016
Takahashi T, Imai M, Suzuki I. Water permeability of chitosan membrane involved in deacetylation degree control. Biochemical Engineering J.. 2007;36: 43–48. DOI: 10.1016/j.bej.2006.06.014
Takahashi T, Imai M, Suzuki I. Cellular structure in an N-acetyl-chitosan membrane regulate water permeability. Biochemical Engineering J.. 2008;42: 20–27. DOI: 10.1016/j.bej.2008.05.013
Santos C, Seabra P, Veleirinho B, Delgadillo I, Lopes da Silva J A. Acetylation and molecular mass effects on barrier and mechanical properties of shortfin squid chitosan membranes. European Polymer J.. 2006;42: 3277–3285. DOI: 10.1016/j.eurpolymj.2006.09.001
Ghosh A, Ali M A, Walls R. Modification of microstructural morphology and physical performance of chitosan films. International J. Biological Macromolecules. 2010;46: 179–186. DOI: 10.1016/j.ijbiomac.2009.11.006
Jin J, Song M, Hourston D J. Novel chitosan-based films cross-linked by genipin with improved physical properties. Biomacromolecules. 2004;5: 162–168. DOI: 10.1021/bm034286m
Remuñán-López C, Bodmeier R. Mechanical, water uptake and permeability properties of crosslinked chitosan glutamate and alginate films. J. Controlled Release. 1997;44: 215–225. DOI: 10.1016/S0168-3659 (96)01525-8
Lee Y M, Nam S Y, Woo D J. Pervaporation of ionically surface crosslinked chitosan composite membranes for water-alcohol mixtures. J. Membrane Science. 1997;133: 103–110. DOI: 10.1016/S0376-7388 (97)00089-6
Devi D A, Smitha B, Sridhar S, Aminabhavi T M. Pervaporation separation of isopropanol/water mixtures through crosslinked chitosan membranes. J. Membrane Science. 2005;262: 91–99. DOI: 10.1016/j.memsci.2005.03.051
Cottrell I W, Kovacs P. Alginate. In: Davidson R L, editor.Handbook of water-soluble gums and resins. New York: McGraw-HillInc.;1980. P. 2-1–2-43.
Baffoun A, Viallier P, Dupuis D, Haidara H. Drying morphologies and related wetting and impregnation behaviours of ‘sodium-alginate/urea’ inkjet printing thickeners. Carbohydrate Polymers. 2005; 61: 103–110. DOI: 10.1016/j.carbpol.2005.03.018
Richardson J C, Dettmar P W, Hampson F C, Melia C D. Oesophageal bioadhesion of sodium alginate suspensions: 2. Suspension behaviour on oesophageal mucosa.European J. Pharmaceutical Sciences. 2005; 24: 107–114. DOI: 10.1016/j.ejps.2004.10.001
Rescignano N, Fortunati E, Armentano I, Hernandez R, Mijangos C, Pasquino R, Kenny J M. Use of alginate, chitosan and cellulose nanocrystals as emulsion stabilizers in the synthesis of biodegradable polymeric nanoparticles. J. Colloid Interface Science. 2015; 445: 31–39. DOI: 10.1016/j.jcis.2014.12.032
Yang Y, Campanella O H, Hamaker B R, Zhang G, Gu Z. Rheological investigation of alginate chain interactions induced by concentrating calcium cations. Food Hydrocolloids. 2013; 30: 26–32. DOI: 10.1016/j.foodhyd.2012.04.006
Li J, He J, Huang Y, Li D, Chen X. Improving surface and mechanical properties of alginate films by using ethanol as a co-solvent during external gelation. Carbohydrate Polymers. 2015; 123: 208–216. DOI: 10.1016/j.carbpol.2015.01.040
Ha T L B, Quan T M, Vu D N, Si D M. Naturally Derived Biomaterials: Preparation and Application. In: Andrades J A, editor. Regenerative Medicine and Tissue Engineering. Croatia: InTech; 2013. p. 247–274. DOI: 10.5772/55668
Kashima K, Imai M. Impact factors to regulate mass transfer characteristics of stable alginate membrane performed superior sensitivity on various organic chemicals. Procedia Engineering. 2012; 42: 964–977. DOI: 10.1016/j.proeng.2012.07.490
Toti U S, Aminabhavi T M. Different viscosity grade sodium alginate and modified sodium alginate membranes in pervaporation separation of water + acetic acid and water + isopropanol mixtures. J. Membrane Science. 2004;228: 199–208. DOI: 10.1016/j.memsci.2003.10.008
Kalyani S, Smitha B, Sridhar S, Krishnaiah A. Pervaporation separation of ethanol–water mixtures through sodium alginate membranes. Desalination. 2008;229: 68–81. DOI: 10.1016/j.desal.2007.07.027
Saraswathi M, Madhusudhan Rao K, Prabhakar M N, Prasad C V, Sudakar K, Naveen Kumar H M P, Prasad M, Chowdoji Rao K, Subha M C S. Pervaporation studies of sodium alginate (SA)/dextrin blend membranes for separation of water and isopropanol mixture. Desalination. 2011;269: 177–183. DOI: 10.1016/j.desal.2010.10.059
Li Y, Jia H, Cheng Q, Pan F, Jiang Z. Sodium alginate–gelatin polyelectrolyte complex membranes with both high water vapor permeance and high permselectivity. J. Membrane Science. 2011;375: 304–312. DOI: 10.1016/j.memsci.2011.03.058
Taşkın G, Şanlı O, Asman G. Swelling assisted photografting of itaconic acid onto sodium alginate membranes. Applied Surface Science. 2011;257: 9444–9450. DOI: 10.1016/j.apsusc.2011.06.030
Chen J H, Liu Q L, Hu S R, Ni J C, He Y S. Adsorption mechanism of Cu (II) ions from aqueous solution by glutaraldehyde crosslinked humic acid-immobilized sodium alginate porous membrane adsorbent. Chemical Engineering J.. 2011;173: 511–519. DOI: 10.1016/j.cej.2011.08.023
Li Y, Jia H, Pan F, Jiang Z, Cheng Q. Enhanced anti-swelling property and dehumidification performance by sodium alginate–poly (vinyl alcohol)/polysulfone composite hollow fiber membranes. J. Membrane Science. 2012;407–408: 211–220. DOI: 10.1016/j.memsci.2012.03.049
Nigiz F U, Dogan H, Hilmioglu N D. Pervaporation of ethanol/water mixtures using clinoptilolite and 4A filled sodium alginate membranes. Desalination. 2012;300: 24–31. DOI: 10.1016/j.desal.2012.05.036
Sajjan A M, Jeevan Kumar B K, Kittur A A, Kariduraganavar M Y. Novel approach for the development of pervaporation membranes using sodium alginate and chitosan-wrapped multiwalled carbon nanotubes for the dehydration of isopropanol. J. Membrane Science. 2013;425–426: 77–88. DOI: 10.1016/j.memsci.2012.08.042
Flynn E J, Keane D, Holmes J D, Morris M A. Unusual trend of increasing selectivity and decreasing flux with decreasing thickness in pervaporation separation of ethanol/water mixtures using sodium alginate blend membranes. J. Colloid and Interface Science. 2012;370: 176–182. DOI: 10.1016/j.jcis.2011.12.022
Shi J, Shi J, Du C, Chen Q, Cao S. Thermal and pH dual responsive alginate/CaCO3 hybrid membrane prepared under compressed CO2. J. Membrane Science. 2013;433: 39–48. DOI: 10.1016/j.memsci.2013.01.021
Chen J H, Xing H T, Guo H X, Li G P, Weng W, Hu S R. Preparation, characterization and adsorption properties of a novel 3-aminopropyltriethoxysilane functionalized sodium alginate porous membrane adsorbent for Cr (III) ions. J. Hazardous Materials. 2013;248–249: 285–294. DOI: 10.1016/j.jhazmat.2013.01.042
Zhu Y, Wang Z, Zhang C, Wang J, Wang S. A novel membrane prepared from sodium alginate cross-linked with sodium tartrate for CO2 capture. Chinese J. Chemical Engineering. 2013;21: 1098–1105. DOI: 10.1016/S1004-9541 (13)60574-1
Adoor S G, Rajineekanth V, Nadagouda M N, Rao K C, Dionysiou D D, Aminabhavi T M. Exploration of nanocomposite membranes composed of phosphotungstic acid in sodium alginate for separation of aqueous–organic mixtures by pervaporation. Separation and Purification Technology. 2013;113: 64–74. DOI: 10.1016/j.seppur.2013.03.051
Zhang W, Xu Y, Yu Z, Lu S, Wang X. Separation of acetic acid/water mixtures by pervaporation with composite membranes of sodium alginate active layer and microporous polypropylene substrate. J. Membrane Science. 2014;451: 135–147. DOI: 10.1016/j.memsci.2013.09.027
Gao C, Zhang M, Ding J, Pan F, Jiang Z, Li Y, Zhao J. Pervaporation dehydration of ethanol by hyaluronic acid/sodium alginate two-active-layer composite membranes. Carbohydrate Polymers. 2014;99: 158–165. DOI: 10.1016/j.carbpol.2013.08.057
Kuila S B, Ray S K. Dehydration of dioxane by pervaporation using filled blend membranes of polyvinyl alcohol and sodium alginate. Carbohydrate Polymers. 2014;101: 1154–1165. DOI: 10.1016/j.carbpol.2013.09.086
Kuila S B, Ray S K. Separation of benzene–cyclohexane mixtures by filled blend membranes of carboxymethyl cellulose and sodium alginate. Separation and Purification Technology. 2014;123: 45–52. DOI: 10.1016/j.seppur.2013.12.017
Yang J-M, Wang N-C, Chiu H-C. Preparation and characterization of poly (vinyl alcohol)/sodium alginate blended membrane for alkaline solid polymer electrolytes membrane. J. Membrane Science. 2014;457: 139–148. DOI: 10.1016/j.memsci.2014.01.034
Pasini Cabello S D, Mollá S, Ochoa N A, Marchese J, Giménez E, Compañ V. New bio-polymeric membranes composed of alginate-carrageenan to be applied as polymer electrolyte membranes for DMFC. J. Power Sources. 2014;265: 345–355. DOI: 10.1016/j.jpowsour.2014.04.093
Cao K, Jiang Z, Zhao J, Zhao C, Gao C, Pan F, Wang B, Cao X, Yang J. Enhanced water permeation through sodium alginate membranes by incorporating graphene oxides. J. Membrane Science. 2014;469: 272–283. DOI: 10.1016/j.memsci.2014.06.053
Yoo S M, Ghosh R. Fabrication of alginate fibers using a microporous membrane based molding technique. Biochemical Engineering J.. 2014;91: 58–65. DOI: 10.1016/j.bej.2014.07.006
Kamoun E A, Kenawy E-R S, Tamer T M, El-Meligy M A, Eldin M S M. Poly (vinyl alcohol)-alginate physically crosslinked hydrogel membranes for wound dressing applications: Characterization and bio-evaluation. Arabian J. Chemistry. 2015;8: 38–47. DOI: 10.1016/j.arabjc.2013.12.003
Li J, He J, Huang Y, Li D, Chen X. Improving surface and mechanical properties of alginate films by using ethanol as a co-solvent during external gelation. Carbohydrate Polymers. 2015;123: 208–216. DOI: 10.1016/j.carbpol.2015.01.040
Soazo M, Báez G, Barboza A, Busti P A, Rubiolo A, Verdini R, Delorenzi N J. Heat treatment of calcium alginate films obtained by ultrasonic atomizing: Physicochemical characterization. Food Hydrocolloids. 2015;51: 193–199. DOI: 10.1016/j.foodhyd.2015.04.037
Zhao K, Zhang X, Wei J, Li J, Zhou X, Liu D, Liu Z, Li J. Calcium alginate hydrogel filtration membrane with excellent anti-fouling property and controlled separation performance. J. Membrane Science. 2015;492: 536–546. DOI: 10.1016/j.memsci.2015.05.075
Jie G, Kongyin Z, Xinxin Z, Zhijiang C, Min C, Tian C, Junfu W. Preparation and characterization of carboxyl multi-walled carbon nanotubes/calcium alginate composite hydrogel nano-filtration membrane. Materials Letters. 2015;157: 112–115. DOI: 10.1016/j.matlet.2015.05.080
Kirdponpattara S, Khamkeaw A, Sanchavanakit N, Pavasant P, Phisalaphong M. Structural modification and characterization of bacterial cellulose–alginate composite scaffolds for tissue engineering. Carbohydrate Polymers. 2015;132: 146–155. DOI: 10.1016/j.carbpol.2015.06.059
Shao W, Liu H, Liu X, Wang S, Wu J, Zhang R, Min H, Huang M. Development of silver sulfadiazine loaded bacterial cellulose/sodium alginate composite films with enhanced antibacterial property. Carbohydrate Polymers. 2015;132: 351–358. DOI: 10.1016/j.carbpol.2015.06.057
Uragami T, Banno M, Miyata T. Dehydration of an ethanol/water azeotrope through alginate-DNA membranes cross-linked with metal ions by pervaporation. Carbohydrate Polymers. 2015;134: 38–45. DOI: 10.1016/j.carbpol.2015.07.054
Haug A, Larsen B, Smidsrød O. A study of the constitution of alginic acid by partial acid hydrolysis. Acta Chemica Scandinavica. 1966;20: 183–190. DOI: 10.3891/acta.chem.scand.20-0183
Haug A, Larsen B, Smidsrød O. Uronic acid sequence in alginate from different sources. Carbohydrate Research. 1974;32: 217–225. DOI: 10.1016/S0008-6215 (00)82100-X
Gacesa P. Alginates. Carbohydr. Polym. 1988;8: 161–182. DOI: 10.1016/0144-8617 (88)90001-X
Draget K I, Smidsrød O, Skjåk-Bræk G. Alginates from algae. In: Steinbuchel A, Rhee S K, editors. Polysaccharides and Polyamides in the Food Industry, Properties, Production and Patents. Weinheim: Wiley–VCH; 2005. P. 1-30. DOI: 10.1002/3527600035.bpol6008
Grant G T, Morris E R, Rees D A, Smith P J C, Thom D. Biological interactions between polysaccharides and divalent cations: The egg-box model. FEBS Letters. 1973;32: 195–198. DOI: 10.1016/0014-5793 (73)80770-7
Kashima K, Imai M. Advanced membrane material from marine biological polymer and sensitive molecular-size recognition for promising separation technology. In: Ning R Y, editor. Advancing Desalination. Croatia: InTech; 2012. p. 3–36. DOI: 10.5772/50734
Bitter T, Muir H M. A modified uronic acid carbazole reaction. Analytical Biochemistry. 1962;4: 330–334. DOI: 10.1016/0003-2697 (62)90095-7
Anzai H, Uchida N, Nishide E. Determination of D-mannuronic to L-guluronic acids ratio in acid hydrolysis of alginate under improved conditions. Nippon Suisan Gakkaishi. 1990;56: 73–81. DOI: 10.2331/suisan.56.73
Anzai H, Uchida N, Nishide E. Comparative studies of colorimetric analysis for uronic acids. Bulletin of the College of Agriculture and Veterinary Medicine Nihon University. 1986;43: 53–56 (in Japanese).
Wilke C R, Chang P. Correlation of diffusion coefficients in dilute solutions. A. I. Ch. E. J. 1955;1: 264–270. DOI: 10.1002/aic.690010222
Smidsrød O. Molecular basis for some physical properties of alginates in the gel state. Faraday Discussions of the Chemical Society.1974; 57: 263–274. DOI: 10.1039/DC9745700263
Donati I, Paoletti S. Material Properties of Alginates, In: B H. A. Rehm editor, Alginates: Biology and Applications. Berlin: Springer; 2009. p. 1–53. DOI: 10.1007/978-3-540-92679-5_1
So M T, Eirich F R, Strathmann H, Baker R W. Preparation of Asymmetric Loeb-Sourirajan Membranes. J. Polymer Science: Polymer Letters Edition. 1973;11: 201–205. DOI: 10.1002/pol.1973.130110311