pH-Based Detection of Target Analytes in Diluted Serum Samples Using Surface Plasmon Resonance Immunosensor
- 46 Downloads
Detection of minute quantities of target antigens in serum samples (consisting of a mixture of proteins/biomolecules) can be achieved by enhancement of the capture efficiencies of heterogeneous immunosensors. An important process parameter which affects the capture of target analytes in such immunosensors is the pH of the solution as the target proteins present in the serum samples are charged molecules. Here, we investigated the capture of prostate-specific antigens (PSAs), first in a mixed-analyte system wherein the solution contained two other non-specific proteins along with the target analyte, using the surface plasmon resonance spectroscopy. There are no reports on the detection of antigens in a mixed system based on the optimization of the pH values of the carrier fluid, and this is the motivation of the present work. Further, we studied interference effects caused by the presence of these non-specific proteins in the mixed-analyte systems by artificially increasing the ratio of the interfering proteins to that of the target protein. Eventually PSA spiked into the rabbit serum samples was captured through the optimization of the pH of the solution. We could detect PSA in the serum samples when diluted to 100 times or more, where the amounts of other interfering proteins were ~ 66 times that of the amount of PSA. This study proposes a heterogeneous immunosensor to detect the target analytes in the diluted serum samples by tuning pH the of solution mixture, which can be utilized to detect disease biomarkers in serum samples.
KeywordsMixed analyte Surface plasmon resonance Serum Prostate specific antigens
Financial support was provided by the DST Science and Engineering Research Board, India (Grant No. SB/S3/CE/055/2013).
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
- 12.Gnedenko, O. V., Mezentsev, Y. V., Molnar, A. A., Lisitsa, A. V., Ivanov, A. S., & Archakov, A. I. (2013). Highly sensitive detection of human cardiac myoglobin using a reverse sandwich immunoassay with a gold nanoparticle-enhanced surface plasmon resonance biosensor. Analytica Chimica Acta, 759, 105–109.CrossRefGoogle Scholar
- 21.Piliarik, M., Vaisocherová, H., & Homola, J. (2009). Surface plasmon resonance biosensing BT—biosensors and biodetection. In A. Rasooly & K. E. Herold (Eds.), (pp. 65–88). Totowa: Humana Press.Google Scholar
- 22.Nagai, H., Tomioka, K., & Okumura, S. (2018). Optimal conditions for the asymmetric polymerase chain reaction for detecting food pathogenic bacteria using a personal SPR sensor. Applied Biochemistry and Biotechnology. https://doi.org/10.1007/s12010-018-2819-y.
- 25.Choi, J.-W., Kang, D.-Y., Jang, Y.-H., Kim, H.-H., Min, J., & Oh, B.-K. (2008). Ultra-sensitive surface plasmon resonance based immunosensor for prostate-specific antigen using gold nanoparticle–antibody complex. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 313–314, 655–659.CrossRefGoogle Scholar
- 29.Nador, J., Orgovan, N., Fried, M., Petrik, P., Sulyok, A., Ramsden, J. J., Korosi, L., & Horvath, R. (2014). Enhanced protein adsorption and cellular adhesion using transparent titanate nanotube thin films made by a simple and inexpensive room temperature process: application to optical biochips. Colloids and Surfaces. B, Biointerfaces, 122, 491–497.CrossRefGoogle Scholar
- 30.Moldovan, C., Mihailescu, C., Stan, D., Ruta, L., Iosub, R., Gavrila, R., Purica, M., & Vasilica, S. (2009). Characterization of self-assembled monolayers (SAMs) on silicon substrate comparative with polymer substrate for Escherichia coli O157:H7 detection. Applied Surface Science, 255(22), 8953–8959.CrossRefGoogle Scholar
- 32.Liu, N., & Ma, Z. (2013). Au-ionic liquid functionalized reduced graphene oxide immunosensing platform for simultaneous electrochemical detection of multiple analytes. Biosensors & Bioelectronics, 51C, 184–190.Google Scholar
- 33.Wang, Y., Li, X., Cao, W., Li, Y., Li, H., Du, B., & Wei, Q. (2014). Facile fabrication of an ultrasensitive sandwich-type electrochemical immunosensor for the quantitative detection of alpha fetoprotein using multifunctional mesoporous silica as platform and label for signal amplification. Talanta, 129, 411–416.CrossRefGoogle Scholar
- 35.Manning, P. J. (1994). The biology of the laboratory rabbit (2nd ed.). San Diego: Academic Press, Inc.Google Scholar