title: Water-Soluble Dried Blood Spot in Protein Analysis: A Proof-of-Concept Study.
abstract: In the present work human chorionic gonadotropin (hCG) was used as a model protein in a proof-of-concept study combining water-soluble dried blood spot (DBS) material in liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based protein analysis. A water-soluble material consisting of commercially available carboxymethyl cellulose (CMC) was evaluated as sampling material for this purpose. The material dissolved readily at physiological pH. Different sample preparation methods were evaluated, and in the final method, 15 μL of whole blood was deposited and dried on CMC before the whole spot was dissolved prior to cleanup by immunoaffinity extraction, tryptic digest, and preconcentration by solid-phase extraction (SPE). The results indicated complete dissolution of hCG from the spots, acceptable limit of detection (LOD) (0.1 IU/mL), linearity (R(2) = 0.959), accuracy (16%), and precision (≤22%). Long-term stability (45 days) of hCG in dried spots at reduced temperatures (≤8 °C) was also demonstrated. The analyte recovery was comparable to the commercially available nonsolvable cellulose material (FTA DMPK-C card).
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, 0316 Oslo, Norway.
authors.forename: Cecilie
authors.initials: C
authors.lastname: Rosting
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, 0316 Oslo, Norway.
authors.forename: Astrid
authors.initials: A
authors.lastname: Gjelstad
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, 0316 Oslo, Norway.
authors.forename: Trine Grønhaug
authors.initials: TG
authors.lastname: Halvorsen
mesh_terms: D001798:Blood Proteins / Q000032:analysis*; D002266:Carboxymethylcellulose Sodium / Q000737:chemistry; D006063:Chorionic Gonadotropin / Q000032:analysis; D002853:Chromatography, Liquid; D059788:Dried Blood Spot Testing / Q000295:instrumentation* / Q000379:methods*; D006801:Humans; D057230:Limit of Detection; D015203:Reproducibility of Results; D012995:Solubility; D053719:Tandem Mass Spectrometry; D014867:Water / Q000737:chemistry*
chemical_list: D001798:Blood Proteins; D006063:Chorionic Gonadotropin; D014867:Water; D002266:Carboxymethylcellulose Sodium