A process for preparing a peptide sample from a biological sample, and a process for detecting or quantifying proteins including the process for preparing a sample. Also disclosed is the use of these processes for the detection or monitoring of a condition or a disease.

Disclosed are methods for identification of one or more non-native disulfide bonds in a biomolecule (e.g, an antibody). In an example, a method includes performing a digestion of the biomolecule under non-reducing conditions to provide a sample comprising a plurality of biomolecule fragments, contacting the sample to a separation column, applying a first mobile phase gradient comprising trifluoroacetic acid (TFA) and a small molecule additive to the separation column, applying a second mobile phase gradient comprising TFA in acetonitrile (ACN) and a small molecule additive to the separation column, performing a partial reduction procedure on the eluted sample, applying the partially reduced eluted sample components to a mass spectrometer, and performing a mass spectrometric analysis on the partially reduced eluted sample components to identify the one or more non-native disulfide bonds in the biomolecule.

A method of ion imaging is disclosed that includes automatically sampling a plurality of different locations on a sample using a front device which is arranged and adapted to generate aerosol, smoke or vapour from the sample. Mass spectral data and/or ion mobility data corresponding to each location is obtained and the obtained mass spectral data and/or ion mobility data is used to construct, train or improved a sample classification model.

A method is disclosed comprising providing a biological sample on a swab, directing a spray of charged droplets onto a surface of the swab in order to generate a plurality of analyte ions, and analysing the analyte ions.

Methods, apparatuses and systems are described that are capable of simultaneously determining the presence, identities or levels of multiple analytes present in a single sample, by carrying out steps including denaturation, normalization, extraction, mixed-mode liquid chromatography and mass spectrometry, whereby the presence, identities or levels of analytes in the single sample are determined.

Disclosed herein are methods and apparatus useful for the collection, preservation, and analysis of biological fluids. In some embodiments, a hydrophobic thread is contacted with a biological sample. The hydrophobic thread stabilizes the biological sample over prolonged periods of time. Compounds, including small molecules and/or biopolymers, can be ionized by applying a suitable voltage to the tread. These ionized compounds can then be analyzed, for instance using mass spectrometry.

Provided are methods for determining the amount of lacosamide in a sample using mass spectrometry. The methods generally involve ionizing lacosamide in a sample and detecting and quantifying the amount of the ion to determine the amount of lacosamide in the sample.

Nutritive polypeptides are provided herein. Also provided are various other embodiments including nucleic acids encoding the polypeptides, recombinant microorganisms that make the polypeptides, vectors for expressing the polypeptides, methods of making the polypeptides using recombinant microorganisms, compositions and formulations that comprise the polypeptides, and methods of using the polypeptides, compositions and formulations.

The present invention relates to a set of two or more mass labels, wherein each mass label comprises the formula:
X-L-M-Re
wherein X is a reporter moiety having an exact mass, L is a bond cleavable by collision in a mass spectrometer, M is a mass modifier, and Re is a) a reactive functionality for attaching the mass label to an analyte or b) the analyte, wherein each mass label in the set has an integer mass, wherein each mass label in the set has the same integer mass, and wherein the set comprises two or more subsets of mass labels, each subset comprising one, two or more mass labels, and wherein, when the subset comprises two or more mass labels, the exact mass of the reporter moiety X of each mass label in the subset is different from the exact mass of the reporter moiety X of the mass labels in the same subset and in all other subsets, and wherein each mass label is distinguishable by mass spectrometry.

Provided are methods for the detection or quantitation of amyloid beta. In a particular aspect, provided herein are methods for detecting amyloid beta or fragments thereof by mass spectrometry. In another aspect, provided herein are methods for determining the ratio of amyloid beta 42 (Aβ42) to amyloid beta 40 (Aβ40). In another aspect, provided herein are methods for diagnosis or prognosis of Alzheimer's disease or dementia.