Efficient extraction of intact HSA-Aβ peptide complexes from sera: Toward albuminome biomarker identification

Talanta. 2020 Aug 15;216:121002. doi: 10.1016/j.talanta.2020.121002. Epub 2020 Apr 9.

Abstract

The performances of three commercial albumin extraction methods for the isolation of intact albumin-amyloid beta peptide (HSA-Aβ) complexes from serum were compared using different analytical approaches. To determine the extraction yield, the repeatability and the selectivity of the extraction procedures, a capillary electrophoresis coupled to UV detection method was developed. For the evaluation of the specificity and integrity of the extracted HSA-Aβ complexes, SDS-PAGE, hybrid and ultra-sensitive ELISA experiments were conducted. All the extraction methods showed different characteristics depending on their chemical binding affinities toward albumin. The ProteoExtract Albumin Depletion kit extracted albumin with a high repeatability but was not efficient for the extraction of intact HSA-Aβ complexes. The PureProteome Albumin magnetic beads showed a high specificity toward HSA thanks to the grafting of anti-HSA antibodies on their surface but tended to dissociate HSA from Aβ peptides. The Pierce Albumin depletion kit showed a high extraction yield, no selectivity towards the different albumin proteoforms and proved to be the most efficient method for the extraction of intact HSA-Aβ complexes from serum.

Keywords: Albuminome; Amyloid beta peptide; Biomarker; Capillary electrophoresis; ELISA; Sample preparation.

MeSH terms

  • Amyloid beta-Peptides / blood
  • Amyloid beta-Peptides / chemistry*
  • Biomarkers / analysis
  • Electrophoresis, Capillary
  • Electrophoresis, Polyacrylamide Gel
  • Humans
  • Serum Albumin, Human / analysis*
  • Ultraviolet Rays

Substances

  • Amyloid beta-Peptides
  • Biomarkers
  • Serum Albumin, Human