The emergence of nanoparticles(NPs)has attracted tremendous interest of the scientific community for decades due to their unique properties and potential applications in diverse areas,including drug delivery and therapy.Many novel NPs have been synthesized and used to reduce drug toxicity,improve bio-availability,prolong circulation time,control drug release,and actively target to desired cells or tissues.However,clinical translation of NPs with the goal of treating particularly challenging diseases,such as cancer,will require a thorough understanding of how the NP properties influence their fate in biological systems,especially in vivo.Many efforts have been paid to studying the interactions and mechanisms of NPs and cells.Unless deliberately designed,the NPs in contact with biological fluids are rapidly covered by a selected group of biomolecules especially proteins to form a corona that interacts with biological systems.In this view,the recent development of NPs in drug delivery and the interactions of NPs with cells and proteins are summarized.By understanding the protein-NP interactions,some guidelines for safety design of NPs,challenges and future perspectives are discussed.
The stimuli-responsive nanomaterials are gaining more and more interest in the biological field,including cell imaging and biosensing etc. Nanomaterials in response to the bio-relevant stimuli(i.e., p H, enzymes and other bioactive molecules) can be utilized to enhance imaging(i.e., optical imaging, MRI, and multi-mode imaging) sensitivity via disease site-specific delivery and controlled release, which helps to diagnose cancer at an early stage or to monitor progression during treatment. In the triggered responsive process, smart nanomaterials undergo changes in physiochemical properties that can cause cytotoxicity or influence on cell functions due to the interactions between nanomaterials and cells. In order to promote the design and fabrication of effective platforms for therapeutics and diagnostics, special attention should be paid to these effects. By taking the advantages of intracellular stimuli, the controlled self-assembly in living cells can be achieved, which has been used for various in situ detections and insights into biological self-assembly. In this review, the recent advances in cell imaging, cytotoxicity and self-assembly of intracellular stimuli-responsive nanomaterials are summarized. Some principles for the further design and applications of intracellular stimuli-responsive nanomaterials and future perspectives are discussed.
The surface-grafted poly(hydroxylethyl methacrylate)(PHEMA)molecules were demonstrated to show a brush state regardless of their molecular length(molecular weight).Adsorption of proteins from 10%fetal bovine serum(FBS),fibronectin(Fn)and bovine serum albumin(BSA)was quantified by ellipsometry,revealing that the amounts of FBS and Fn decreased monotonously along with the increase of PHEMA thickness,whereas not detectable for BSA when the PHEMA thickness was larger than 6 nm.Radio immunoassay found that the adsorption of Fn from 10%FBS had no significant difference regardless of the PHEMA thickness.However,ELISA results showed that the Arg-Gly-Asp(RGD)activity of adsorbed Fn decreased with the increase of PHEMA thickness.By comparison of cellular behaviors of vascular smooth muscle cells(VSMCs)being cultured in vitro in the normal serum-containing medium and the Fn-depleted serum-containing medium,the significant role of Fn on modulating the adhesion and migration of VSMCs was verified.Taking account all the results,the Fn adsorption model and its role on linking the biomaterials surface to the VSMCs behaviors are proposed.
Jun DengTanchen RenJiyu ZhuZhengwei MaoChangyou Gao
