Sensing of Oligopeptides Using Alternatively-Deposited Gold Nanorods for Surface-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry

ABSTRACTGold nanorods (NRs) were fixed on an ITO plate and used for the Surface-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SALDI-MS) of oligopeptides (angiotensin I). The SALDI-MS measurements had a high sensitivity to the angiotensin on the ITO plate on which isolated NRs were deposited. Angiotensin molecules in a very diluted solution (1 × 10-11 M) could be detected at m/z = 1297 with a good signal/noise ratio (S/N = 18). In contrast, alternatively deposited NR an ITO plate, which present broad surface plasmon bands, was found to be inactive for SALDI measurements.