A stable, Ag55 cluster protected with 4-(tert-butyl)benzyl mercaptan (BBSH) was synthesized which exhibits two prominent absorption bands with maxima at 2.25 and 2.81 eV. A molecular ion peak at m/z 11 500 ± 20 in matrix assisted laser desorption ionization mass spectrum (MALDI MS), assigned to Ag55(BBS)31 was observed. Electrospray ionization (ESI MS) shows a prominent trication along with hig...

A nonenzymatic digestion technique allows proteins to be well suited for collision-induced dissociation tandem mass spectrometry. This method utilizes microwaves and Dithiothreitol (DTT) to selectively cleave at aspartic acid (D) and disulfide bonds. This microwave digestion technique is reproducible and produces peptides with a shortened sequence length. Insulin I is used in this study to opti...

Real-time optical spectrum analysis is an essential tool in observing ultrafast phenomena, such as the dynamic monitoring of spectrum evolution. However, conventional method such as optical spectrum analyzers disperse the spectrum in space and allocate it in time sequence by mechanical rotation of a grating, so are incapable of operating at high speed. A more recent method all-optically stretch...

Analysis of biochemicals in single cells is important for understanding cell metabolism, cell cycle, adaptation, disease states, etc. Even the same cell types exhibit heterogeneous biochemical makeup depending on their physiological conditions and interactions with the environment. Conventional methods of mass spectrometry (MS) used for the analysis of biomolecules in single cells rely on exten...

The quantity of ablated mass and its composition strongly depend on the number of laser pulses and laser fluence at the sample target surface. For chemical analysis, thin-film deposition, cutting, and other laser-ablation applications, the quantity of mass removed vs. number of laser pulses is important. In addition, the composition of the vapor can be critical, for example, in providing accura...

A high-throughput matrix-assisted laser desorption ionisation-time of flight (MALDI-TOF) mass spectrometry (MS)-based method was here developed to genotype 16 high-risk human papillomavirus (HPV) types in cervical cytology specimens. This method was compared to a commercial kit, the Inno-LiPA HPV genotyping assay, which detects a broad spectrum of HPV types. HPV DNA was assessed by the two meth...

Aedes aegypti PISCF-allatostatin or allatostatin-C (Ae-AS-C) was isolated using a combination of high performance liquid chromatography and enzyme-linked immunosorbent assay (ELISA). The matrix-assisted laser desorption/ionization time-of-flight (TOF) mass spectrum of positive ELISA fractions revealed a molecular mass of 1919.0 Da, in agreement with the sequence qIRYRQCYFNPISCF, with bridged cy...

MOTIVATION Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry has been broadly adopted by routine clinical microbiology laboratories for bacterial species identification. An isolated colony of the targeted microorganism is the single prerequisite. Currently, MS-based microbial identification directly from clinical specimens can not be routinely performed, as it raises ...