Abstract:
Toxicity assessments are required for nanomaterials which are being used in many fields such as medicines, electronics, pesticides, clothes and construction materials. One factor that usually affects toxicity of chemicals is chirality. This paper reviews the existence of chirality in nanoparticles and critically analyses the implications of chirality on toxicological risk assessment of nanoparticles. Chirality and optical activity arise from lack of symmetry, where an object is non-superimposable on its mirror image. Optical isomers or enantiomers have similar physico-chemical properties but only differ in their optical activity and their interaction with biological systems. Chirality is not limited to organic molecules, but also exists in inorganic compounds and crystals. Studies have also shown that chirality can be bestowed onto nanoparticles by adsorption of chiral molecules, and by careful design of the crystal to expose chiral kinked and stepped surface structures. Just as chirality has been shown to affect the biological activities of conventional chemicals, nanoparticles functionalised with different enantiomers have been shown to exhibit enantioselectivity and different toxicities. However, at the moment more studies on the ligands and the conditions under which chirality occurs in NPs, as well as on the effects of NP chirality on protein adsorption kinetics and thermodynamics. Nevertheless, this cursory analysis has shown the importance of chirality on biological activity of nanoparticles. In cases where there is a potential for the existence of chirality in nanomaterials (either intrinsic or extrinsic), there may be need for adequate consideration of the effects of chirality.
摘要:
在药物等许多领域使用的纳米材料需要进行毒性评估,电子,杀虫剂,服装和建筑材料。通常影响化学品毒性的一个因素是手性。本文回顾了纳米粒子中手性的存在,并批判性地分析了手性对纳米粒子毒理学风险评估的影响。手性和光学活动源于缺乏对称性,其中对象在其镜像上不可叠加。旋光异构体或对映体具有相似的物理化学性质,但仅在它们的光学活性和它们与生物系统的相互作用方面不同。手性不仅限于有机分子,而且还存在于无机化合物和晶体中。研究还表明,手性分子的吸附可以赋予纳米颗粒手性,并通过仔细设计晶体来暴露手性扭结和阶梯状表面结构。正如手性已经被证明会影响常规化学品的生物活性一样,用不同对映体官能化的纳米颗粒已被证明具有对映选择性和不同的毒性。然而,目前,对配体和在NP中发生手性的条件进行了更多的研究,以及NP手性对蛋白质吸附动力学和热力学的影响。然而,这个粗略的分析显示了手性对纳米粒子生物活性的重要性。在纳米材料(内在或外在)中可能存在手性的情况下,可能需要充分考虑手性的影响。