Sensitive bioaffinity assays with individual microparticles and time-resolved fluorometry.

T Lövgren; P Heinonen; P Lehtinen; H Hakala; J Heinola; R Harju; H Takalo; V M Mukkala; R Schmid; H Lönnberg; K Pettersson; A Iitiä

PubMed · 9342016

Sensitive bioaffinity assays with individual microparticles and time-resolved fluorometry.

T Lövgren·P Heinonen·P Lehtinen·H Hakala·J Heinola·R Harju·H Takalo·V M Mukkala·R Schmid·H Lönnberg·K Pettersson·A Iitiä

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Abstract

Future immunoassays and nucleic acid hybridization assays will be performed in miniaturized formats that utilize microchips or microparticles. This will require a sensitive detection technology that allows spatial resolution. By using fluorescent europium chelates and time-resolved microfluorometry, one can detect 11,000 europium molecules on individual microparticles. In a miniaturized noncompetitive immunoassay of prostate-specific antigen (PSA), we quantitatively detected 5 ng/L (0.05 amol per particle) of the analyte on an individual microparticle with excellent precision over the whole measurement range (CV <10%). Using a hybridization assay, we also could detect the deltaF508 mutation for cystic fibrosis on individual microparticles. Consequently, fluorescent lanthanide chelate labels and time-resolved microfluorometry qualify as the next generation of technology in this field.

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Chelating Agents Cystic Fibrosis Europium Humans Immunoassay Mutation Prostate-Specific Antigen Sensitivity and Specificity Spectrometry, Fluorescence Time Factors Journal Article

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T Lövgren, P Heinonen, P Lehtinen, H Hakala, J Heinola, R Harju, H Takalo, V M Mukkala, R Schmid, H Lönnberg, K Pettersson, A Iitiä. 1997. Sensitive bioaffinity assays with individual microparticles and time-resolved fluorometry.. https://pubmed.ncbi.nlm.nih.gov/9342016/

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