Methods for quantifying the amount of drug present in a crosslinked hyaluronic acid-linker-peptide (xHA-L-P) prodrug composition are provided. Disclosed are steps of contacting a sample of the xHA-L-P prodrug formulation with a hyaluronoglucosidase to generate oligomeric hyaluronic acid-linker-peptide drug (oHA-L-P), contacting the oHA-L-P with a second enzyme to generate peptide digest products of the drug, and detecting the peptide digest products to determine the amount of the drug present in the xHA-L-P prodrug formulation.

The invention relates to the quantitative measurement of steroidal compounds by mass spectrometry. In a particular aspect, the invention relates to methods for quantitative measurement of steroidal compounds from multiple samples by mass spectrometry.

The present disclosure provides methods and compositions for the determining the abundance and/or concentration of protein biomarkers in a biological sample.

The present invention provides assays and assay systems for use in spatially encoded biological assays. The invention provides an assay system comprising an assay capable of high levels of multiplexing where reagents are provided to a biological sample in defined spatial patterns; instrumentation capable of controlled delivery of reagents according to the spatial patterns; and a decoding scheme providing a readout that is digital in nature.

The invention relates to methods and systems taking advantage of bioinformatic investigations to identify candidate signature peptides for quantitative multiplex analysis of complex protein samples from plants, plant parts, and/or food products using mass spectroscopy. Provided are use and methods for selecting candidate signature peptides for quantitation using a bioinformatic approach. Also provided are systems comprising a chromatography and mass spectrometry for using selected signature peptides.

The present disclosure relates to a group of peptide compounds and their use in identifying molecules that stimulate proteasome or immunoproteasome are disclosed herein. Composition matters and methods of uses are within the scope of this disclosure.

A method of purification and/or separation of glycopeptides and quantitation of same. The method includes contacting a sample comprising glycopeptides to a hydrophilic enrichment substrate under conditions that permit the glycopeptides to bind to the hydrophilic enrichment substrate. The glycopeptides are eluted from the hydrophilic enrichment substrate with an ammonium formate and acetonitrile (ACN) in water solution to create an enriched glycopeptide sample, which may be subjected to analysis to identify specific glycopeptides.

Disclosed are methods of quantifying multiple quality attributes, such as post translational modifications, of multiple samples in a single mass spectrometry (MS) run, including contacting two or more samples with a digesting solution under conditions sufficient to digest samples, wherein each sample is digested separately and the digesting solution is a Tris-free buffer solution; contacting each of the two or more digested samples with a specific Tandem Mass Tag (TMT) labeling reagent under conditions sufficient to label peptides within each of the digested samples with the specific TMT labeling reagent; quenching labeling of peptides within each of the two or more digested samples; combining equal volumes of the two or more labeled, digested samples into a single combined sample solution; and analyzing the single combined sample solution by targeted mass spectral analysis, thereby allowing multiple quality attributes of the two or more samples to be quantified in a single mass spectrometry (MS) run.

Disclosed herein are methods of processing a protein and detecting isoaspartic acid (isoAsp) in a protein. Also disclosed are mass spectrometry systems configured for of processing a protein and detecting isoAsp in a protein.

The technology described herein is directed to methods for detection of microbes and microbe components. In some embodiments of any of the aspects, the methods comprise methods of microbe isolation, sample preparation, mass spectrometry, or analysis. In some embodiments of any of the aspects, such methods can be applied to detect at least one microbe or at least one microbial component in a sample, including not limited to a patient sample, an animal model sample, an environmental sample, or a non-biological sample.