The application of semiconductor quantum dots for enhancing peptide desorption, improving peak resolution and sensitivity of detection in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry.

The interest in quantum dots (QD) and a number of reported life sciences applications increased dramatically over the last decade. The popularity of QDs stems from better photostability, higher extinction -co-efficients, and unique optical properties such as superior light absorption. Here we report methods for improving matrix-assisted laser desorption/ionization desorption of crude tryptic protein digests by using CdSe/ZnS QDs. The addition of QDs to the matrix improves the signal-to-noise ratio, peak quality and increases the number of detected peptides and the overall sequence coverage.