Related Experiment Video
Updated: May 28, 2026

Microsampling in Targeted Mass Spectrometry-Based Protein Analysis of Low-Abundance Proteins
Published on: January 13, 2023
Application of DBS for the quantitative assessment of a protein biologic using on-card digestion LC-MS/MS or
Jonathan Kehler1, Neha Akella, David Citerone
1Platform Technology & Science, Drug Metabolism & Pharmacokinetics, GlaxoSmithKline Pharmaceuticals, 709 Swedeland Road, King of Prussia, PA 19406, USA. jonathan.r.kehler@gsk.com
Background:
Dried blood spot (DBS) sampling has recently gained popularity in the bioanalysis community for quantitation of small molecules. Since the pharmaceutical industry continues to increase investment in biopharmaceuticals, DBS technologies were investigated to determine if immunoassay and/or LC-MS/MS techniques would be amenable for quantitation of a large protein therapeutic (>70 kDa).
Results:
Methods were successfully qualified for the protein therapeutic utilizing DBS technology. DBS methods in rat blood were qualified for this therapeutic protein using either immunoassay or enzymatic digestion directly off the DBS card followed by UHPLC-MS/MS separation and detection. Both qualifications were carried out in accordance with current acceptable practices defined by international acceptance criteria. Card selection was critical to both DBS methods.
Conclusion:
The advantages gained by DBS technology can successfully be applied to the quantitative assessment of biologics. This UHPLC-MS/MS method illustrates that digestion of large molecules directly off blood spot cards allows quantitation of these molecules. In addition, DBS technologies are amenable to immunoassay analysis. The immunoassay was 20-fold more sensitive than the UHPLC-MS/MS method, however the UHPLC-MS/MS assay had a much broader dynamic range.
More Related Videos
08:10High Throughput, Absolute Determination of the Content of a Selected Protein at Tissue Levels Using Quantitative Dot Blot Analysis (QDB)
Published on: August 21, 2018
11:09An HS-MRM Assay for the Quantification of Host-cell Proteins in Protein Biopharmaceuticals by Liquid Chromatography Ion Mobility QTOF Mass Spectrometry
Published on: April 17, 2018
Related Concept Videos
Western Blotting
The technique begins with separating proteins from the sample using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), followed by protein transfer, immunoblotting, and finally, protein detection.
Peptide Identification Using Tandem Mass Spectrometry
This technique helps gather information regarding the protein from which the peptide was obtained and to study the peptides’ amino acid sequence. Identifying peptides from a complex mixture is an important component of the growing field of...
MALDI-TOF Mass Spectrometry