Determination of Antibody Population Distributions for Virus-Antibody Conjugates by Charge Detection Mass Spectrometry.
Kevin M BondIoana L AaneiMatthew B FrancisMartin F JarroldPublished in: Analytical chemistry (2019)
Virus-like particle (VLP) conjugates are being developed for biomedical applications; however, there is a lack of quantitative analytical methods to measure the extent of conjugation and modification of VLP based therapeutics. Charge detection mass spectrometry (CDMS) can measure mass distributions for large and heterogeneous complexes and is emerging as a valuable tool in the analysis of biologics. In this study, CDMS is used to characterize the stoichiometry and population distribution of antibodies covalently conjugated to the surface of a bacteriophage MS2 VLP. Initial CDMS analysis of the unconjugated MS2 particles suggested that they had packaged a broad distribution of exogenous genomic material. We developed procedures to remove the undesired genomic material from the VLP preparation and observed that, for the samples where the genomic fragments were removed, the antibody coupling reaction efficiency increased by almost a factor of 2. This meant there were (1) fewer VLPs with no antibodies bound, which is an important consideration for the efficacy of a targeted therapeutic and (2) fewer antibodies were wasted during the coupling reaction. CDMS could be employed in a similar manner as a tool to characterize coupling reaction product distributions and precursors and help inform the development of the next generation of conjugate-based therapies.
Keyphrases
- mass spectrometry
- liquid chromatography
- cancer therapy
- electron transfer
- high resolution
- copy number
- room temperature
- capillary electrophoresis
- gas chromatography
- high performance liquid chromatography
- loop mediated isothermal amplification
- multiple sclerosis
- solid phase extraction
- molecularly imprinted
- label free
- ms ms
- real time pcr
- tandem mass spectrometry
- drug delivery
- small molecule
- monte carlo
- solar cells
- quantum dots