10 results about "Isoelectric focusing" patented technology

Multispecific antibodies with reduced isoelectric focusing points are described herein.

This paper provides a method for detecting low concentrations of amphoteric compounds in a sample, comprising: (a) preparing an analytical sample mixture for capillary isoelectric focusing (CIEF) detection using the sample; and (b) detecting the analytical sample mixture using a fluorescence detector via a CIEF system; wherein the concentration of the low concentration amphoteric compound in the analytical sample mixture is less than 0.5 μg / μL. This method is more resistant to background noise interference and can sensitively detect and accurately quantify low concentrations of amphoteric compounds present in the sample.

The present disclosure relates to fluidic systems and devices for processing, extracting, or purifying one or more analytes. These systems and devices can be used to process samples and extract nucleic acids, for example, by isoelectric focusing. In particular, the systems and related methods can allow for the extraction of nucleic acids, including non-crosslinked nucleic acids, from samples such as tissues or cells. The systems and devices can also be used for multiplexed parallel sample processing.

To provide systems that are configured to perform multiple types of analysis, such as electrophoretic mobility and isoelectric electrophoresis within a single device, and that are automated so that multiple samples are analyzed simultaneously or in rapid succession with ease and robustness while consuming minimal volumes of expensive reagents and disposables.SOLUTION: A system includes: a housing; a cartridge retainer disposed within the housing; a detection assembly disposed within the housing; and a reagent tray holder movably disposed within the housing. The detection assembly is configured to transition between a first configuration, in which a first detector detects a first output of at least one emitter, and a second configuration, in which a second detector detects a second output of the at least one emitter. The reagent tray holder is configured to move relative to the cartridge retainer to place the capillary of a capillary cartridge in fluid communication with a reagent volume.SELECTED DRAWING: Figure 6

Systems and methods for calibrating compound markers in mass spectrometry (MS) detection are disclosed. The systems and methods automatically identify a plurality of isoelectric point (pI) markers in a sample, generate a calibration curve correlating pI with time, and convert the time scale to a pI scale. Based on the established correlation between time and pI, the system further associates pI with intensity values, enabling presentation to an operator for analysis.

The invention relates to a method for determining isoelectric points of proteins and polypeptides, which is characterized in that a capillary isoelectric focusing electrophoresis method or a full-column imaging capillary isoelectric focusing electrophoresis method is used for determining according to a 214nm absorption peak. The method provided by the invention solves the problem that the isoelectric point of the protein or polypeptide which does not contain a benzene ring structure cannot be measured by a capillary isoelectric focusing electrophoresis method because the protein or polypeptide does not have ultraviolet absorption under the wavelength of 280 nm.

This application discloses a method for detecting charge variants of monoclonal antibodies. The method includes preparing a test solution of the monoclonal antibody to be tested; the test solution includes the monoclonal antibody to be tested, methylcellulose solution, urea, amino acids, an amphoteric electrolyte carrier, and an isoelectric point marker; the test solution is detected using whole-column imaging capillary isoelectric focusing, and the percentage of charge variants of the monoclonal antibody to be tested is determined based on the isoelectric focusing spectrum; wherein the isoelectric point of the amino acid is similar to the isoelectric point of the boundary between the main peak and the base peak in the isoelectric focusing spectrum of the monoclonal antibody to be tested. This method can significantly improve the separation between the main peak and the base peak of the sample. It also exhibits good sensitivity and high precision, while specifically improving the separation between the main peak and the base peak, with minimal impact on the separation and ratio of the acid peak and the main peak, as well as the isoelectric point of the sample.

Methods, devices, and systems for performing isoelectric focusing reactions are described. The systems or devices disclosed herein may comprise fixtures that have a membrane. In some instances, the disclosed devices may be designed to perform isoelectric focusing or other separation reactions followed by further characterization of the separated analytes using mass spectrometry. Two or more isoelectric focusing reactions may be performed in parallel. The disclosed methods, devices, and systems provide for fast, accurate separation and characterization of protein analyte mixtures or other biological molecules by isoelectric point.

In some embodiments, the present disclosure provides an icIEF sample matrix that enables icIEF analysis of a pegylated protein in its actual conjugated state. Sample matrices of the present disclosure can include glycine that enables the isolation of co-migrated PEGylated protein charge variants. The sample matrix can also include taurine that further improves the icIEF assay by eliminating the matrix-caused baseline interference. Thus, the sample matrix of the present disclosure comprising a combination of glycine and taurine enables icIEF separation of acidic and basic species of PEGylated proteins from the main peak, allowing for identification / isolation, characterization and quantification of discrete PEGylated protein species. By characterizing PEGylated proteins via icIEF using a sample matrix of the present disclosure, repeatability, linearity, accuracy, sample stability, and method robustness are achieved.