Immunosensor for okadaic acid using quartz crystal microbalance
2002 (English)In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 471, no 1, 33-40 p.Article in journal (Refereed) Published
An immunosensor for the determination of okadaic acid (OA) using a quartz crystal microbalance (QCM) was developed and optimised in standard solutions. Several coupling techniques, protein A, protein G and polyethylenimine (PEI) with glutaraldehyde (GA) cross-linking, were investigated for the determination of okadaic acid and a very good result was obtained with PEI coupling. With the PEI coupling method, the optimisation of incubation time for the activation of PEI on the crystal surface using GA, the effect of the dilution factor of OA-bovine serum albumin (BSA) conjugate and the amount of antibody on crystal frequency were studied. Different molar ratios (4:1, 14:1, 30:1) of OA to bovine serum albumin for the conjugation were examined and the results using ELISA and a QCM showed that a ratio of 14:1 was slightly better than the other two. The strong attachment of the cross-linked complex to the gold surface resulted in an excellent storage lifetime of 38 days. However, the detection limit (1.9 mug/ml) and the sensitivity of the sensor were not satisfactory. Significant improvement of the performance of the device was obtained by incorporating an antibody-BSA hydrogel. Initial results showed that the minimum amount of analyte detectable and the sensitivity of the device were improved by 524- and 80-fold, respectively. (C) 2002 Elsevier Science B.V. All rights reserved.
Place, publisher, year, edition, pages
Elsevier Science B.V., Amsterdam. , 2002. Vol. 471, no 1, 33-40 p.
quartz crystal microbalance; immunosensor; okadaic acid; anti-okadaic acid monoclonal antibody; antibody-BSA hydrogel
National CategoryEngineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-65210ISI: 000178565700004OAI: oai:DiVA.org:liu-65210DiVA: diva2:395024