2007

Direct Analysis of Living Objects by Extractive Electrospray Ionization Mass Spectrometry

Direct Analysis of Living Objects by Extractive Electrospray Ionization Mass Spectrometry

H. Chen and R. Zenobi

Spinach contaminated with E. coli leaves 200 people sick in the USA – rapid screening needed for suspected food! Epidemic − thousands of patients need to be rapidly screened in emergencies… What do these and similar headlines have in common? They all challenge modern analytical science in terms of sensitivity, specificity, speed, and especially throughput. It appears that …

Neutral Desorption Sampling of Living Objects for Rapid Analysis by Extractive Electrospray Ionization Mass Spectrometry

Neutral Desorption Sampling of Living Objects for Rapid Analysis by Extractive Electrospray Ionization Mass Spectrometry

H. Chen, S. Yang, A. Wortmann, and R. Zenobi

Mass spectrometry is increasingly used for research purposes and routine measurements in biology, life science, the pharmaceutical industry, and in clinic diagnosis to characterize complex samples. Usually, biological samples are mixtures supported by a biological structure such as skin, tissue, muscle, or vessels and are commonly accompanied by microorganisms …

Neutral desorption sampling coupled to extractive electrospray ionization mass spectrometry for rapid differentiation of biosamples by metabolomic fingerprinting

Neutral desorption sampling coupled to extractive electrospray ionization mass spectrometry for rapid differentiation of biosamples by metabolomic fingerprinting

H. Chen, A. Wortmann, Renato Zenobi

It is of increasing interest and practical importance to develop convenient methods based on mass spectrometry for high-throughput analyses of biological samples. This is usually difficult because of the complex matrix and ion suppression effects. Generation of ions at ambient conditions is a promising solution to these problems …

Differentiation of Maturity and Quality of Fruit Using Noninvasive Extractive Electrospray Ionization Quadrupole Time-of-Flight Mass Spectrometry

Differentiation of Maturity and Quality of Fruit Using Noninvasive Extractive Electrospray Ionization Quadrupole Time-of-Flight Mass Spectrometry

H. Chen, Y. Sun, A. Wortmann, H. Gu, R. Zenobi

Maturity is an essential factor that determines storage life and final quality of most fruits and vegetables. Maturity monitoring is thus of paramount importance for postharvest handling and fruit quality regulation. Ideal analytical procedures for maturity investigation require high sensitivity, specificity, and high throughput and should be noninvasive.

Manipulation of charge states of biopolymer ions by atmospheric pressure ion/molecule reactions implemented in an extractive electrospray ionization source

Manipulation of charge states of biopolymer ions by atmospheric pressure ion/molecule reactions implemented in an extractive electrospray ionization source

H. Chen, D. Touboul,M. C. Jecklin, J. Zheng, M. Luoa, Renato Zenobid

A home-made extractive electrospray ionization source is coupled to a linear quadrupole ion trap mass spectrometer to investigate ion/molecule reactions of biopolymers at ambient pressure. Multiply charged biopolymers such as peptides and proteins generated in an electrospray are easily reduced to a low charge state by …

Rapid In Vivo Fingerprinting of Nonvolatile Compounds in Breath by Extractive Electrospray Ionization Quadrupole Time-of-Flight Mass Spectrometry

Rapid In Vivo Fingerprinting of Nonvolatile Compounds in Breath by Extractive Electrospray Ionization Quadrupole Time-of-Flight Mass Spectrometry

H. Chen, A. Wortmann, W. Zhang, and R. Zenobi

Quantitative analysis of trace constituents in exhaled gas can provide useful insights into biochemical processes in the body, thus revealing information about metabolic dynamics and providing, theoretically, a scientific base for biomarker research or clinical diagnoses. Breath, however, is rarely used practically for diagnostic purposes in clinical medicine …