Surface modification to reduce nonspecific binding of quantum dots in live cell assays

Nonspecific binding is a frequently encountered problem with fluorescent labeling of tissue cultures when labeled with quantum dots. In these studies various cell lines were examined for nonspecific binding. Evidence suggests that nonspecific binding is related to cell type and may be significantly reduced by functionalizing quantum dots with poly(ethylene glycol) ligands (PEG). The length of PEG required to give a significant reduction in nonspecific binding may be as short as 12-14 ethylene glycol units.