Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) is used for the multiplex detection and characterization of diverse analytes over a wide mass range directly from tissues. However, analyte coverage with MALDI MSI is typically limited to the more abundant compounds, which have m/z values that are distinct from MALDI matrix-related ions. On-tissue analyte deriva...

Label-free detection of biomolecules using an optical whispering-gallery mode sensor in a microelectrofluidic channel is simulated. Negatively charged bovine serum albumin is considered as the model protein analyte. The analyte transport in aqueous solution is controlled by an externally applied electrical field. The finite element method is employed for solving the equations of the charged spe...

Newton AJ, Wall MJ, Richardson MJ. Modeling microelectrode biosensors: free-flow calibration can substantially underestimate tissue concentrations. J Neurophysiol 117: 937–949, 2017. First published December 2, 2016; doi:10.1152/jn.00788.2016.—Microelectrode amperometric biosensors are widely used to measure concentrations of analytes in solution and tissue including acetylcholine, adenosine, g...

Ion abundances in the MALDI TOF mass spectra of the model peptides (bradykinin, alpha-melanocyte stimulating hormone, and melittin) change significantly as water is added to the solution used for dried droplet sample preparation. Changes in the surface tension of the solution can be invoked to explain some of the observed effects on the mass spectra. For example, at low surface tensions, the so...