Nonspecific Adsorption of Charged Quantum Dots on Supported Zwitterionic Lipid Bilayers: Real-Time Monitoring by Quartz Crystal Microbalance with Dissipation Xinfeng Zhang Shihe Yang 10.1021/la104449y.s001 https://acs.figshare.com/articles/journal_contribution/Nonspecific_Adsorption_of_Charged_Quantum_Dots_on_Supported_Zwitterionic_Lipid_Bilayers_Real_Time_Monitoring_by_Quartz_Crystal_Microbalance_with_Dissipation/2683609 Understanding how the composition and environmental conditions of membranes influence their interactions with guest species is central to cell biology and biomedicine. We herein study the nonspecific adsorption of charged quantum dots (QDs) onto a supported zwitterionic lipid bilayer by using quartz crystal microbalance with dissipation (QCM-D). It is demonstrated that (1) the adsorption of charged QDs is charge-dependent in a way similar to but much stronger than that of the capping molecules by reason of size effect; (2) the adsorption behavior of charged QDs is dominated by electrostatic interaction, which can be well described by an “adsorption window”; (3) the “adsorption window” can be broadened by exploiting the bridge role of Ca<sup>2+</sup> ions; and (4) by introducing a cationic lipid into the zwitterionic lipid bilayer, one can achieve preferential adsorption of anionic QDs but suppression of the cationic QD adsorption. Our QCM-D data also indicates that these different adsorption traits effect different changes in the dissipation of supported lipid bilayers (SLBs) after adsorption of the charged QDs. The different adsorption propensities of cationic and anionic QDs on SLBs have reinforced the picture of electrostatic interactions. We believe that these findings provide important information on QD−lipid membrane interactions, which will help to develop new drug molecules and efficient drug delivery systems, and to predict and unravel their potential toxicities if any. 2011-03-15 00:00:00 Quartz Crystal Microbalance Charged Quantum Dots guest species Zwitterionic Lipid Bilayers bridge role zwitterionic lipid bilayer cell biology cationic lipid lipid bilayers interaction drug delivery systems membranes influence drug molecules size effect SLB adsorption propensities quartz crystal microbalance Nonspecific Adsorption quantum dots adsorption behavior cationic QD adsorption adsorption traits effect