Part of the book: Drug Discovery
Part of the book: Application of Nanotechnology in Drug Delivery
Over the past years, there has been significant interest in the study of nanoparticles for clinical applications, particularly quantum dots (QDs). However, previous studies have also shown that QDs can reach the embryo through the placenta, a natural barrier for a large variety of organic substances with diverse molecular structures, and may cause developmental deformities. Due to its essential role in a toxicological profile and its relevance to human safety, knowledge regarding embryotoxicity is of great importance. Previous studies by this research group have shown that CdS‐maltodextrin QDs are biocompatible and nontoxic to cells and animals; however, QDs are able to induce embryotoxic effects. Therefore, as an effort to further address the issue, we studied the effects of CdS‐maltodextrin QDs on embryo and fetus development using an embryotoxicity and teratogenicity assay on chicken embryos. Chicken embryos exposed to CdS‐maltodextrin QDs (0.001, 0.01, 0.1 and 1 µg/kg) in ovo for 72 h showed growth and developmental alterations during the early stage and at the end of their development in a dose‐dependent manner. Decreased development was observed during early stages (Stages 9/10 on the Hamburger‐Hamilton scale) when compared with untreated eggs (Stage 13). Chicken embryos exposed to lower CdS‐maltodextrin QDs doses (0.01, 0.1 and 1 ng/kg) and incubated in ovo for 21 h also showed growth and development alterations during the early stages and at the end of their development in a dose‐dependent manner. However, reduced development was observed at the end of the development period (21 days), and this was associated with death of the chick. Current studies have also shown that CdS‐dextrin induces embryotoxicity and teratogenicity, affecting mainly the CNS, the neural tube and somites in chicken embryos. The nature of the observed abnormalities suggests that these effects could be directly associated with nanoparticle concentrations affecting somitogenesis. Therefore, according to the results, there is a high probability that the prolonged accumulation of QDs in the maternal organism may be potentially harmful on embryo and fetus development. This study is limited to the analysis of embryotoxic and teratogenic effects induced by CdS‐maltodextrin QDs.
Part of the book: Toxicology
Nanotechnology currently plays a pivotal role in several fields and has enabled substantial advances in a relatively short time. In biomedicine, nanomaterials can be potentially employed as a tool for early diagnosis and an innovative mode of drug delivery. Novel nanomaterials are currently widely manipulated without a full assessment of their potential health risks. It is commonly thought that nanomaterials’ first contact with the organism is through the different components of the immune system. However, if the entry route is intravenous, the first contact will be with the blood’s components (erythrocytes, platelets, white cells, plasma and complement proteins). The presence of nanomaterials within a dynamic environment such as the bloodstream can produce potential harmful effects following interaction with several blood components. The design of innovative strategies leading to the development of more hemocompatible nanomaterials is also necessary.
Part of the book: Unraveling the Safety Profile of Nanoscale Particles and Materials