TitleInvestigation of Reagent Delivery Formats in a Multivalent Malaria Sandwich Immunoassay and Implications for Assay Performance.
Publication TypeJournal Article
Year of Publication2016
AuthorsLiang, T, Robinson, R, Houghtaling, J, Fridley, G, Ramsey, SA, Fu, E
JournalAnal Chem
Date Published2016 Feb 16
KeywordsAntibodies, Antigen-Antibody Reactions, Antigens, Immunoassay, Indicators and Reagents, Malaria, Protozoan Proteins

Conventional lateral flow tests (LFTs), the current standard bioassay format used in low-resource point-of-care (POC) settings, have limitations that have held back their application in the testing of low concentration analytes requiring high sensitivity and low limits of detection. LFTs use a premix format for a rapid one-step delivery of premixed sample and labeled antibody to the detection region. We have compared the signal characteristics of two types of reagent delivery formats in a model system of a sandwich immunoassay for malarial protein detection. The premix format produced a uniform binding profile within the detection region. In contrast, decoupling the delivery of sample and labeled antibody to the detection region in a sequential format produced a nonuniform binding profile in which the majority of the signal was localized to the upstream edge of the detection region. The assay response was characterized in both the sequential and premix formats. The sequential format had a 4- to 10-fold lower limit of detection than the premix format, depending on assay conjugate concentration. A mathematical model of the assay quantitatively reproduced the experimental binding profiles for a set of rate constants that were consistent with surface plasmon resonance measurements and absorbance measurements of the experimental multivalent malaria system.

Alternate JournalAnal Chem
PubMed ID26835721
PubMed Central IDPMC6387624
Grant ListR01 AI096184 / AI / NIAID NIH HHS / United States
R01AI096184 / AI / NIAID NIH HHS / United States