Abstract: Disclosed are native liquid chromatography-mass spectrometry systems and methods of use. A native liquid chromatography-mass spectrometry system can include a liquid chromatography system capable of separating a sample; and an electrospray ionization mass spectrometry (ESI-MS) system in fluid communication with the liquid chromatography system, wherein the ESI-MS system comprises a multi-nozzle electrospray ionization emitter and a system for modifying a desolvation gas and a mass spectrometer, wherein the mass spectrometer is configured to receive ions and characterize mass to charge ratio of ions.

Abstract: The present disclosure pertains to compositions comprising anti-VEGF proteins and methods for producing such compositions.

Abstract: The present invention provides rapid, sensitive high-throughput methods and systems for characterizing peptides or proteins using hydrophobic interaction chromatography-coupled native mass spectrometry to improve manufacturing process of biopharmaceutical products, such as identifying impurities during antibody purification, monitoring post-translational modification variants during production, or characterizing drug-to-antibody ratio of antibody-drug conjugates. The separation profiles of the peptides or proteins are generated and compared to identify or qualify the peptides or proteins.

Abstract: Methods and system for identifying and/or quantifying a protein are provided herein.

Abstract: The present disclosure pertains to compositions comprising anti-VEGF proteins.

Abstract: The present disclosure pertains to compositions comprising anti-VEGF proteins and methods for producing such compositions.

Abstract: Systems and methods to characterize dimerization interfaces at the subdomain level of a protein are provided. An exemplary method includes digesting a protein dimer sample into subdomains, labeling the digested protein sample, isolating labeled dimeric and monomeric subdomain fragments, and peptide mapping the labeled sample to determine where the dimer fragments are labeled and where the dimer fragments are not labeled. Regions that show decreased labeling extents in the dimer fraction than that in the monomer fraction are likely involved or in close proximity to the dimerization interface.

Abstract: The present invention relates to the field of protein characterization, and in particular to methods for characterizing high molecular weight species of a therapeutic protein by implementing a workflow including using a post-column denaturation-assisted SEC-MS method that allows highly specific, sensitive, and comprehensive characterization of high molecular weight species.

Abstract: Liquid chromatography-free methods for quantitating a target protein in a sample are provided. One embodiment provides a liquid chromatography-free method for quantifying target antibodies in a sample including the steps of spiking the sample with a labeled internal standard antibody, digesting the antibodies in the sample to produce peptides, fractionating the peptides; and quantifying the target antibodies using a direct infusion MS2 system containing one or more ion traps and two or more quadrupole mass filters and an electrospray ionizer, wherein the method is liquid chromatography-free.

Abstract: 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.

Abstract: Disclosed are native liquid chromatography-mass spectrometry systems and methods of use. A native liquid chromatography-mass spectrometry system can include a liquid chromatography system capable of separating a sample; and an electrospray ionization mass spectrometry (ESI-MS) system in fluid communication with the liquid chromatography system, wherein the ESI-MS system comprises a multi-nozzle electrospray ionization emitter and a system for modifying a desolvation gas and a mass spectrometer, wherein the mass spectrometer is configured to receive ions and characterize mass to charge ratio of ions.

Abstract: The present disclosure pertains to compositions comprising anti-VEGF proteins.

Abstract: The present invention provides VEGF mini-trap molecules and method of treating or preventing angiogenic disorders such as angiogenic eye disorders and cancer.

Abstract: Compositions and methods for analyzing disulfide bonds are provided. An exemplary method includes preparing peptide standards having no disulfide bonds, scrambled disulfide bond peptide standards, and native disulfide bond peptide standards according to the sequence of the region of the protein drug product that includes the disulfide bond, digesting a sample of protein drug product into peptides, separating the protein drug product peptides, analyzing the protein drug product peptides and the peptide standards, identifying scrambled and native disulfide bond peptides by retention time, and quantifying the level of scrambled disulfide bond peptides.

Abstract: The present disclosure pertains to compositions comprising anti-VEGF and methods for producing such compositions in chemically defined media and controlling amounts of certain oxidized aflibercept variants.

Abstract: The present invention relates to the field of protein characterization, and in particular to methods for identifying critical quality attributes of therapeutic proteins expressed in host cells by implementing a workflow including using a competitive binding assay with insufficient antigen followed by SCX-MS.

Abstract: The present invention relates to the field of protein characterization, and in particular to methods for identifying critical quality attributes of therapeutic proteins by implementing a workflow including using a competitive binding assay with insufficient capture molecule followed by LC-MS.

Abstract: The present invention generally pertains to methods of determining the amino acid sequence of a protein. In particular, the present invention pertains to the use of position-selective dimethylation and liquid chromatography-mass spectrometry to enhance the signal of N-terminal peptides and shift the signal of N-terminal peptides and corresponding b ions, thus facilitating a determination of the sequence of N-terminal peptides.

Abstract: The present invention generally pertains to methods of characterizing charge variants of a protein. In particular, the present invention pertains to the use of anion exchange chromatography-mass spectrometry (AEX-MS) methods using a salt-gradient. The present invention is particularly useful for charge variant analysis of IgG4 subclasses.

Abstract: The present invention generally pertains to methods of characterizing antibodies and related products. In particular, the present invention pertains to the use of immunoprecipitation and native strong cation exchange chromatography-mass spectrometry to specifically and sensitively detected and quantitate antibodies and related products in a sample.