Cellular level evaluation and lysozyme adsorption regulation of bimodal nanoporous silica

The present work initially evaluated cellular toxicity and uptake of our previous biomimetic bimodal nanoporous silica (B-BNS) and applied it as lysozyme adsorbent, which aimed to study potential ability of B-BNS as antitumor biological macromolecules carrier. To highlight the advantage of bimodal mesopores, comparisons were made between single mesoporous silica nanoparticles (S-MSN) and B-BNS. Cell evaluation work was conducted using MCF-7 cells and lysozyme adsorption process was studied with pH and lysozyme concentration as independent variables. The results indicated that the toxicity of S-MSN and B-BNS on MCF-7 cell could be neglected. In addition, S-MSN and B-BNS had the ability to be uptaken into cells and even nucleus evidenced by inverted fluorescence microscope and confocal laser scanning microscopic. Compared to S-MSN, B-BNS adsorbed larger amount of lysozyme due to its bimodal mesopores. Lysozyme adsorption was favorably approximated by the pseudo-second order model. The equilibrium data of lysozyme adsorption were fitted to the Langmuir isotherm model much better than the Freundlich isotherm model, suggesting that lysozyme adsorption on B-BNS via the monolayer adsorption process. Overall, B-BNS can be considered as good antitumor biological macromolecules carrier.