01825nas a2200205   4500008004100000022001400041245011600055210006900171260000800240300001200248490000700260520109500267653003001362653002201392653002101414653003001435100001901465700000501484856013001489       2021                        eng d  a0934-086600aAmphifunctional mesoporous silica nanoparticles with ``molecular gates'' for controlled drug uptake and release0 aAmphifunctional mesoporous silica nanoparticles with molecular g  cDEC  a21001850 v383 aIt is demonstrated that the uptake and release of hydrophobic drugs/dyes by mesoporous silica nanoparticles (MSN) is critically dependent on the functional groups present on their outer surfaces. For this, amphifunctional MSNs are synthesized, possessing hydrophobic pores and hydrophilic functional groups on the outer surface. Further, the outer surface is modified with a different chain length of molecules, e.g., propargyl alcohol, triethylene glycol, and PEG (2000) via azide-alkyne click chemistry. The effect of these different surface functional groups on uptake of drug/dye is demonstrated with Nile red, proflavine (free base form), and rhodamine 6G. The uptake of these molecules is found to be inversely proportional to the bulkiness of surface functionality. To counter this effect, an alternate method of loading is proposed and demonstrated. Finally, the effect of these different functional groups on the release of loaded drug proflavine is studied, which supports the hypothesis that bulkier outer surface groups also hinder the release of drugs loaded in the porous MSN.10adrug delivery and release10aMesoporous silica10amolecular gating10asurface functionalization1 aShinde, Pravin1 a  uhttps://library.ncl.res.in/content/amphifunctional-mesoporous-silica-nanoparticles-molecular-gates-controlled-drug-uptake-and