Rajendra Dongre

By Rajendra S. Dongre

About 70% of the Earth's surface is covered with seawater and 90% biosphere wraps maximum biodiversity that offers resourceful novel bio‐molecules. Marine species are enriched with organic compounds viz. terpenoids, polyethers/ketides, lipo‐glycoproteins, peptides and polysaccharides that act as cell surface receptors and involve in cell development/differentiation, besides being antimicrobial agents. Algae, sponge and fish have various defense mechanisms developed via specific/potent natural molecules to survive under hostile, extreme conditions such as various degrees of salinity, pressure, temperature, darkness, besides microbial and viral attacks. Marine seaweeds and algae enriched with polysaccharides such as glycosaminoglycans, agar, alginate and chitin/chitosan owing to their diversified significance have received growing attention among researchers. Currently, marine‐derived biomolecules cater 20% market drug load while other natural products bear 30% share. Chitins exhibit various biological and physicochemical properties that can be exploited in biotechnology and medicine/drug, cosmetic, food and textile industries. This chapter focuses on chitin/chitosan production, its physicochemical characterization and biological activities and relationship between its chemical structure and bio‐activity, including chemical modification reactions such as acylation, substitution, sulfonation and other cross‐linking strategies applied to skeletal modification with the recently updated literature.

Part of the book: Biological Activities and Application of Marine Polysaccharides

By Rajendra S. Dongre

Rationally designed nanomaterials from synthetic/biopolymers like chitosan, zeolites, graphene, nanometal/oxides, zerovalent metal/magnetic iron, OMS and nanocarbon/carbon nanotube (CNT) utilized in desalination/purification are thoroughly discussed. Conventional desalination membrane/materials own inherent limitations; nevertheless, designed nanocomposite/hybrid/films address the new challenges/constraints and consequently aid the remediation of environmental/water pollution, thus denoting prospective nanotechnology/science. The morphology and chemical functionality of certain natural/synthetic polymers are altered/controlled rationally yielding advanced membranes/materials, for example, aquaporin, nanochannels, graphene and smart self-assemble block copolymer blends to cater futuristic desalination needs besides superseded conventional membrane limitations too. In a nut shell, advance nanotechnology via electrospinning, track-etching, phase inversion and interfacial polymerization yields structured composites/matrixes that conquer traditional barriers of conventional desalination and supplies treated/purified water. This review confers synthetic strategy and utility of nanomaterials that are procured via ordered/rational designing/self-assembly to be used in separation techniques including RO/FO antifouling membrane, superwet surface, oil-water/emulsion separation and multifunctional desalination nanodevices.

Part of the book: Novel Nanomaterials

By Rajendra Sukhadeorao Dongre

Part of the book: Chitin-Chitosan

By Rajendra Sukhadeorao Dongre

Today growing science and technological needs explored various biopolymers to procure novel utilities in its modern developments. Consequently, polysaccharides embraced huge prospective and vastly caters such desired growing needs. Amid, chitin the second most ubiquitous after cellulose comprise of β-[1,4]-2-acetamido-2-deoxy-d-glucose flexible skeleton undergo alteration for requisite physico-chemical features and its highly sophisticated utility superseded counterpart cellulose. Chitosan have unique parameters namely bio-compatibility, non-toxicity, hemeostaticity, anti-microbials which offer competent solutions of many challenging problems. Thus, many products namely biomarkers, biosensors, quantum dots are fabricated via adoptable productive chitosan matrixes. Advancement in chitosan chemistry proffers unambiguous industrial utility in cosmetics, pharmaceuticals, nanobiotechnology, water purifications etc. Chitosan composites own enhanced muco-adhesivity that aids pharmacological safe and successful DNA/SiRNA/tissue releases with bioavailability at target specific carriers. ZnO, ZnS, TiO2 filled/imposed in chitosan and resultant hybrids, quantum dots, surface active microcapsules and nanoparticles are used as biosensors, bio-markers, adsorbents that proffers revolutionary medical usage. Nanointegrated chitosan own complementary strengths and possess assorted utility namely nano-electronic high-resolution devices, for in-vivo imaging, diseases diagnosis, generating new therapeutic and smart tissue engineering scaffolds. Novel modalities with innovative formulations are skillfully designed via chitosan matrix for myriad benefit in biology, chemistry, polymer, and pharmaceutics are displayed in this chapter.

Part of the book: New Trends in Ion Exchange Studies

By Roshan D. Nasare, Mohammad Idrees, Satish S. Kola and Rajendra S. Dongre

Pharmaceutics and therapeutics industries enforced chemists to seek/discover antibacterial novel heterocycles owing specific bioactivity and innate characteristics significance. This chapter summarized potent antibacterial profile of 5-oxo-imidazolines in the new millennium as an antibacterial against Gram-positive and Gram-negative bacteria viz. B. thuringiensis, S. aureus, E. coli, and E. aerogenes is presented in this chapter. 5-(H/Br benzofuran-2-yl)-1-phenyl 1H-pyrazole-3-carbohydrazides are condensed with 4-(arylidene)-2 phenyloxazol-5(4H)-one in acetic acid at elevated temperature to yield product 5-(H/Br benzofuran-2-yl)-N-(4-arylidene-5-oxo-2-phenyl-4,5-dihydroimidazol-1-yl)-1-phenyl-1H-pyrazole-3-carboxamides. Different substrates like 4-(arylidene)-2-phenyloxazol-5(4H)-one allowed to react with benzaldehyde hippuric acid to yield 5-oxo-imidazolines/5-oxo-4,5-dihydroimidazole. All synthesized 5-oxo-imidazolines were characterized via elemental analysis and FT-IR, 1H-NMR and mass spectra techniques. All 5-oxo-imidazolines assayed in vitro for inherent antimicrobial activity at different concentration against stated bacterial strains and compared with standard chloramphenicol. 5-Oxo-imidazolines (3a and 3c) with 125 μg/mL concentration showed excellent antibacterial profile against Gram-positive bacteria, B. thuringiensis, while other derivatives at different concentrations showed moderate antibacterial activity against Gram-positive bacteria, S. aureus and B. thuringiensis. Gram-negative bacteria like E. coli and E. aerogenes are tested at higher concentration (1000, 500, and 125 μg/mL) and found good-to-moderate antibacterial activity. Tested products found non-active against E. aerogenes for 125, 61, and 31 μg/mL concentration also inactive at conc. 31 μg/mL against E. coli.

Part of the book: Heterocycles

By Rajendra Sukhadeorao Dongre

Since long scientists explored natural/bio-polymers to explicit their innate features to develop certain novel utilities in modernization of prevalent Science & Technology. Consequently biotope derived polysaccharide embrace huge prospective desired functions. Amid, chitosan, the second most ubiquitous polymer after cellulose exists as a β-(1–4)-linked d-glucosamine/N-acetyl-d-glucosamine randomly distributed linear polycationic yield from partial deacetylation of chitin polysaccharide. Chitin’s complexity limits its extraction/insolubility in aqueous solution, thus less studied/research until 1980s. As major polysaccharides are either neutral/negatively charged in an acidic environment, instead chitosan is cationic, eventually forms electrostatic complexes/multilayer structures/composites with anionic synthetic dopants/natural polymers. Chitosan own biocompatibility, non-toxicity, low allergy and biodegradability allow utility as in water treatment, wound-healing, pharmaceutical excipient/drug carrier, obesity treatment and scaffold for tissue engineering. It is reflected in the increasing number of related publications throughout in biomedical, environmental and industrials applications. Feeble chitosan solubility limits their applications, yet benign synthetic techniques viz.; sol-gel, encapsulation, chemical grafting are employed to yield composites/hydrogels/films/granules which generates new functionality, besides enhanced biocompatibility and biodegradability. This chapter presents the R&D, trends and the latest prospects involved in advance synthesis of chitosan supported composites/hydrogels/films/granules/sheets with special highlighted pharmaceutical/biomedical and environmental applications.

Part of the book: Hysteresis of Composites

By Rajendra Sukhadeorao Dongre

Nanotechnology is an ever-expanding field, which offers novel avenues due to advance, unique, and myriad applications in science and technology. Especially composites procured from reconfigurated matrixes appear as multiphase matter tendering augmented/new functionalities via chosen amalgamations. Hence, it is important to meticulously comprehend the interactive materials for the basic reconfiguration of their skeletal matrix to derive desired output to cater to the needs of S&T developments. Nanoscale material’s systematic and rational designing gets fundamental as various material scale manipulations permit to recognize characters and functionalities that are not viable via conventional methods. Material’s skeletal matrix reconfiguration is feasible through advanced biotechnology, physics, chemistry, and nanomaterial engineering mainly decisive to fabricate the particle, thing, and device at the atomic and molecular dimensions. These reconfigurations of material’s matrix reduce its spatial dimension/captivity within crystallographic phase usually changing its physical, mechanical, thermal, optical, and electrical-electronic properties. Reconfigurated material matrixes restrain three nanoporous skeletons, namely: 3D/zero dimensional (e.g., particle, grain, shell, capsule, ring, and colloidal), 2D/one dimension (e.g., quasi crystal, nanorod, filament, tubes, and quantum wire), and 1D/two dimensional (e.g., disc, platelet, ultrathin film, super lattice, and quantum well). Today, rational designing of smart nanomaterials obtained via flexible matrix’s skeletal reconfiguration focus on desired applications in the advancement of science and technology.

Part of the book: Nanostructures

By Rajendra Sukhadeorao Dongre

Rational fabrication of futuristic smart materials like polymer-derived nanocomposites/matrixes is ever desirable due to innate worth in advancement and growth of S&T. Certain nanocomposites are designed from metal-polymeric blends through altering varied parameters like shear stress, shape, size, rate, concentration and processing time, which are best used as fillers. Reinforced fabricated polymer nanocomposites possess exclusive physicochemical characteristics like non-Newtonian/constant viscosity-free stress, time-dependent mechanics, facile shear-skeletal revisions and viscoplastic course controls. Metal-derived nanocomposites/matrixes showed substantial inherent rheology being vulnerable for designing viable applicability in photovoltaics, catalysis, optics, drug delivery, smart material and energy storage. Bottom-up technique is used for self- and directed-assembly of polymer-based building blocks owing to robust fabricated and efficiently manipulated/targeted reinforced 1D, 2D or 3D nanostructures. This chapter reviews some contemporary advances in reconfiguration of rational designing of certain polymeric nanostructures/composites with current and futuristic developments. This overview highlights significance of assured reinforced matrixes in S&T besides disclosed fundamental principles involved in material designing/engineering of multifaceted nanomaterials. Assorted advanced developments are made to avail futuristic prospective of biopolymers, viz. chitin, chitosan, cellulose and lignin in order to offer unequivocally myriad applications in modernization of science and technology in new millennium.

Part of the book: Composite and Nanocomposite Materials

By Rajendra Sukhadeorao Dongre

Water quality is the keen concern all over the world. As water resources get contaminated naturally or artificially, at last they affect our health as well as economic and social development of the nations. Among the prominent chemical pollutants, lead alone has threatened health of billions due to deterioration in water quality. Thus, safe water for drinking becomes a major worried issue of UNICEF as a major stakeholder in sustaining water quality with responsibility to improve and sustain quality of water through its programs around the world. The mitigation of contaminations through effective techniques is the common global effort toward remediation of pollutions. This chapter has investigated viability of ordinary organic waste and natural polymeric material like chitin, chitosan, and doped bio-composite adsorbents for the mitigation of Pb2+ ions from water. The relatively higher adsorption potential of synthesized composites is studied for removing excessive lead concentration from water as tested in batch and column mode. Certain exchangeable metal ions such as Na+, Ca2+, and Mg2+ aid to form solid precipitate, which is effective in Pb2+ retention and facilitate its adsorption. Certain pilot domestic units provide simple, efficient, and fesasible options for removal of Pb2+ ions from water.

Part of the book: Lead Chemistry

By Rajendra Sukhjadeorao Dongre and Dilip R. Peshwe

Part of the book: Assorted Dimensional Reconfigurable Materials