The present invention generally pertains to methods of characterizing charge variants of a protein of interest. In particular, the present invention pertains to the use of desalting size exclusion chromatography-reduced peptide mapping mass spectrometry to identify charge variants separated by capillary isoelectric focusing.

Methods and system for identification of dimer species using online chromatography and electrospray ionization mass spectrometry are provided. Also provided are methods and system for quantitation of heterodimer species using immunoprecipitation and liquid chromatography-mass spectrometry.

Described are techniques for processing data. Sample analysis is performed generating scans of data. Each scan comprises a set of data elements each associating an ion intensity count with a plurality of dimensions including a retention time dimension and a mass to charge ratio dimension. The scans are analyzed to identify one or more ion peaks. Analyzing includes filtering a first plurality of the scans producing a first plurality of filtered output scans. The filtering including first filtering producing a first filtering output, wherein the first filtering includes executing a plurality of threads in parallel which apply a first filter to the first plurality of scans to produce the first filtering output. Each of the plurality of threads computes at least one filtered output point for at least one corresponding input point included in the plurality of scans. Analyzing includes detecting one or more peaks using the filtered output scans.

A detection kit for detecting an immunosuppressor in whole blood by high performance liquid chromatography-tandem mass spectrometry and a detection method thereof is provided. An internal standard solution is added with an antioxidant, vitamin E, and mixed with an internal standard diluent containing zinc sulfate heptahydrate, purified water and methanol for sample pretreatment, which not only exerts the function of the internal standard, but also synchronously achieves erythrocyte treatment, protein precipitation and target substance extraction. Various embodiments enable the immunosuppressor to be more stable in a solution matrix, thus promoting the detection accuracy and sensitivity. Various embodiments adopt isotopically-labeled sirolimus as an internal standard of everolimus to substitute isotopically-labeled everolimus, thus overcoming the interference of everolimus on isotopically-labeled everolimus and satisfying the detection requirements. Various embodiments detect four immunosuppressors simultaneously to reduce the cost of the internal standard, and has a lower detection cost, more accurate and stable detection results.

A data processing device comprises a processor unit adapted to process a plurality of initial data vectors provided by a chromatograph and/or a mass spectrometer, the processing being carried out in one, two or more processing steps producing items of processed data, and a storage unit adapted to save and retrieve initial data vectors and/or items of processed data, in particular processed data vectors or identified compounds, and/or items of additional data, in particular properties of the sample introduced in the mass spectrometer. Each item of processed data and/or additional data is connected to at least one initial data vector, and wherein the processor unit is adapted to group, select and/or modify initial data vectors and/or items of processed data according to one or more items of additional data.

The present invention describes systems, processes, and methods of characterizing a protein or a polypeptide and/or identifying clipping sites on a protein or a polypeptide. In some embodiments, the said systems, processes, and methods comprise generation of reporter ions and subsequent tandem mass spectrometry that is triggered by the reporter ion.

The present invention provides a synchronous detection method of medicaments influencing ARR in the detecting process of renin activity by liquid chromatography-tandem mass spectrometry. The method achieves the qualitative screening of medicaments influencing ARR values while detecting plasma renin activity by liquid chromatography-tandem mass spectrometry; moreover, the method can be used to assist to analyze and judge ARR as negative, positive, false negative or false positive. The detecting method achieves effective extraction of angiotensin I and 43 hypertension therapeutics synchronously through protein precipitation to samples, and enables to perform synchronous detection of a plurality of indices including angiotensin I and 43 hypertension therapeutics on the extracted sample by liquid chromatography-tandem mass spectrometry technology of high throughput, high specificity and high sensitivity. Moreover, the detection method utilizes the MRM mass spectrum parameters for preliminary screening of the medicaments, and rechecks the medicaments according to the retention time thereof. The ARR detection value is combined with the medicament screening result for co-analysis, which effectively distinguishes the false positive or false negative result of the detection while avoiding the patient's withdrawal of medicament for treatment, thereby improving the detection accuracy of the actual primary aldosteronism, and facilitating clinical promotion and application.

The present invention relates to a separation method comprising: i) providing an aqueous solution comprising a target compound; ii) applying a separation step to the aqueous solution, thereby providing a plurality of fractions of the aqueous solution: iii) determining a concentration parameter indicating a concentration of the target compound in at least part of the fractions; iv) determining a nuclear magnetic resonance (NMR) parameter by applying an NMR measurement to the fractions, the NMR parameter indicating a nuclear magnetic spin relaxation in said at least part of the fractions; and v) determining a target parameter of said at least part of the fractions based on the concentration parameter and the nuclear magnetic resonance parameter. The present invention further relates to separation systems, uses, preparations, and methods related thereto.

Exemplary embodiments are directed to devices for separating a sample by chromatography, components of the devices, and methods for using the devices, and directed to devices and components for use with immobilized enzymatic reactors. A device includes a wall having a wetted surface exposed to a mobile phase including the sample during chromatographic separation. The wetted surface of the wall includes an alloy material including the following constituents: nickel, and cobalt and/or chromium where the alloy is limited in an amount of titanium to 1 wt %. A component includes a body having a wetted surface exposed to a mobile phase including the sample during chromatographic separation. The wetted surface of the body includes an alloy material including the following constituents: nickel, and cobalt and/or chromium where the alloy is limited in an amount of titanium to 1 wt %.

A method and an apparatus suitable for a continuous chromatography process which only needs three separation columns, and a two-step process containing two chromatographic steps, in which the first chromatographic step (capture) is performed alternating and sequentially on two separation columns, the second chromatographic step (polishing) is performed, also sequentially, on the third column.