Hydrogen Is the Superior Nebulization Gas for Desorption and Electrospray Ionization.

A previous comparative study between helium and nitrogen as nebulizing and desolvation gases in electrospray ionization (ESI) and desorption electrospray ionization (DESI) found that the signal responses of compounds of varying sizes and polarities were improved. Here, an expanded selection of nebulizing gases was evaluated to investigate mechanisms of improvement. The set of nebulizing gases included hydrogen, helium, nitrogen, argon, and carbon dioxide.

Protein analysis by desorption electrospray ionization mass spectrometry.

This review presents progress made in the ambient analysis of proteins, in particular by desorption electrospray ionization-mass spectrometry (DESI-MS). Related ambient ionization techniques are discussed in comparison to DESI-MS only to illustrate the larger context of protein analysis by ambient ionization mass spectrometry. The review describes early and current approaches for the analysis of undigested proteins, native proteins, tryptic digests, and indirect protein determination through reporter molecules.

Revolutionizing the Pancreatic Tumor Diagnosis: Emerging Trends in Imaging Technologies: A Systematic Review.

: The pancreas, ensconced within the abdominal cavity, requires a plethora of sophisticated imaging modalities for its comprehensive evaluation, with ultrasonography serving as a primary investigative technique. A myriad of pancreatic pathologies, encompassing pancreatic neoplasia and a spectrum of inflammatory diseases, are detectable through these imaging strategies. Nevertheless, the intricate anatomical confluence and the pancreas's deep-seated topography render the visualization and accurate diagnosis of its pathologies a formidable endeavor.

Effects of Amino Acid Additives on Protein Stability during Electrothermal Supercharging in ESI-MS.

The surprising formation of highly charged protein ions from aqueous ammonium bicarbonate solution is a fascinating phenomenon referred to as electrothermal supercharging (ETS). Although the precise mechanism involved is not clearly understood, previous studies predominantly suggest that ETS is due to native protein destabilization in the presence of bicarbonate anion inside the electrospray ionization droplets under high temperatures and spray voltages. To evaluate existing hypotheses surrounding the underlying mechanism of ETS, the effects of several additives on protein charging under ETS conditions were investigated.