Methods are provided for identifying biomarker proteins that exhibit differential expression in subjects with a first lung condition versus healthy subjects or subjects with a second lung condition. Also provided are compositions comprising these biomarker proteins and methods of using these biomarker proteins or panels thereof to diagnose, classify, and monitor various lung conditions. The methods and compositions provided herein may be used to diagnose or classify a subject as having lung cancer or a non-cancerous condition, and to distinguish between different types of cancer (e.g., malignant versus benign, SCLC versus NSCLC).

The present disclosure provides a biosignature that distinguishes Lyme disease, including early Lyme disease, from STARI. The present disclosure also provides methods for detecting Lyme disease and STARI, as well as methods for treating subjects diagnosed with Lyme disease or STARI.

Systems and methods for characterizing low molecular weight (LMW) protein drug product impurities are provided. One embodiment uses hydrophilic interaction chromatography (HILIC) coupled to mass spectrometry analysis. After removal of the N-linked glycans from the protein drug product, for example an antibody drug product, the elution of LMW impurities from the HILIC column was determined by the size of the molecular weight species. In some embodiments, the HILIC separation is performed under denaturing conditions, making the detection of LMW forms using this method highly comparable to both SDS-PAGE and CE-SDS methods. LMW drug product impurities include, but are not limited to light chain, half antibody, H2L, H2, HL, HC, peptide backbone-truncated species, and combinations thereof.

Methods are described for measuring the amount of C peptide in a sample. More specifically, mass spectrometric methods are described for detecting and quantifying C peptide in a sample utilizing on-line extraction methods coupled with tandem mass spectrometric or high resolution/high accuracy mass spectrometric techniques.

Methods of determining the stoichiometry of a viral capsid and/or determining the heterogeneity of protein components in a viral capsid are disclosed.

Methods and apparatuses for the identification and/or characterization of properties of a macromolecule based on mass spectrometry data. Specifically, described herein are methods and apparatuses for converting peptide-level data into a pseudo-intact mass spectra. Also described herein are methods and apparatuses for converting peptide-level data into a pseudo-electropherogram. The methods may be well suited for analyzing proteins and protein complexes, including estimating properties of post-translational modifications of the proteins and protein complexes. Methods may include generating a theoretical graph or spectrum based on peptide-level mass spectrometry data. In some embodiments, the theoretical graph may be a theoretical intact mass spectrum or a theoretical charge distribution spectrum.

A method of analysis using mass and/or ion mobility spectrometry or ion mobility spectrometry is disclosed comprising: using a first device to generate aerosol, smoke or vapour from one or more regions of a first target of biological material; and el mass and/or ion mobility analysing and/or ion mobility analysing said aerosol, smoke, or vapour, or ions derived therefrom so as to obtain first spectrometric data. The method may use an ambient ionisation method.

Provided are methods for detecting chromogranin A by mass spectrometry. In another aspect, provided herein are methods for quantitating chromogranin A by mass spectrometry. In another aspect, provided herein are methods for prognosis of or measuring the size of neuroendocrine tumors by mass spectrometry.

Provided herein are methods for high throughput quantitation of testosterone utilizing at least two different derivatizing agents of different masses. In another aspect, provided herein are methods for determining the amount of testosterone in each of a plurality of human samples with a single mass spectrometric assay by subjecting each of a plurality of human samples to a different derivatizing agent to generate a differently derivatized testosterone in each of the plurality of samples; combining the plurality of samples to form a multiplex sample; and quantifying the amount of testosterone in each sample by mass spectrometry.

An immunoadsorbent and a composite affinity column for purifying fumonisin B1, anguidin, T-2 toxin, zearalenone, and vomitoxin. The immunoadsorbent includes a solid phase carrier, and a fumonisin B1 monoclonal antibody, an anguidin monoclonal antibody, a T-2 toxin monoclonal antibody, a zearalenone monoclonal antibody and a vomitoxin monoclonal antibody which are coupled to the solid phase carrier, the anguidin monoclonal antibody is a monoclonal antibody secreted by a hybridoma cell strain DAS5G11E7 having an accession number of CCTCCNO:C201881. The affinity column can be used for high performance liquid chromatography-mass spectrometry detection of the fumonisin B1, the anguidin, the T-2 toxin, the zearalenone and the vomitoxin, and has stable performance. Furthermore, an economical, quick, precise and safe detection method is established of the basis of the affinity column, and can be used for purifying and detecting samples of the five toxins without mutual interference and influence.