Effect of serum albumin on porphyrin-quantum dot complex formation and characteristics. Spectroscopic analysis

Abstract

The effect of bovine serum albumin (BSA) upon interaction between CdTe QD functional-ized by 3-Mercaptopropionic Acid (CdTe-3-MPA QD) and two water soluble porphyrins: positively charged meso-tetra methyl pyridyl porphyrin (TMPyP) and negatively charged meso-tetrakis(p-sulfonato-phenyl) porphyrin (TPPS4), was studied in function of pH using the steady-state and time resolved optical absorption and fluorescence spectroscopies. It was shown that, depending on the charge state of the components, interaction with albumin could either prevent the formation of the QD … PPh complex, form a mixed QD … PPh … BSA complex or not affect PPh complexation with QD at all. The obtained results may be of interest for application in photomedicine.