Chemical profiling of cerebrospinal fluid by multiple reaction monitoring mass spectrometry.

We report an accelerated biomarker discovery workflow and results of sample screening by mass spectrometry based on multiple reaction monitoring (MRM). This methodology shows promising initial results for the currently unsolved challenge of Parkinson's disease (PD) laboratory diagnosis by biomarker screening. Small molecules present in cerebrospinal fluid (CSF) at low parts per million levels are monitored using specific transitions connecting ion pairs.

Paper spray and extraction spray mass spectrometry for the direct and simultaneous quantification of eight drugs of abuse in whole blood.

Determination of eight drugs of abuse in blood has been performed using paper spray or extraction spray mass spectrometry in under 2 min with minimal sample preparation. A method has been optimized for quantification of amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxy-N-methylamphetamine (MDMA), 3,4-methylenedioxy-N-ethylamphetamine (MDEA), morphine, cocaine, and Δ9-tetrahydrocannabinol (THC) from a single blood spot. Sample to sample variations of 1-5% relative standard deviation were achieved using stable isotope-labeled internal standards and tandem mass spectrometry.

Rapid analysis of whole blood by paper spray mass spectrometry for point-of-care therapeutic drug monitoring.

Paper spray mass spectrometry is applied to oncology drugs in fresh whole blood samples supported on filter paper substrates instead of dry blood as done previously. Addition of the coagulant alum clotted the blood and allowed for immediate sample analysis. The coagulant did not interfere with the function of the paper spray nor did it add features to the mass spectra.

Analysis and modification of surfaces using molecular ions in the ambient environment.

The analysis and modification of surfaces in their native conditions can be performed using new mass spectrometric methods. Ambient ionization sources, including desorption electrospray ionization (DESI), have been implemented for the rapid analysis of unmodified biological surfaces including whole plant material, tissue sections, algae, and bacterial colonies. Recent advances have shown promise for in vivo and high-throughput clinical analysis.