Detection of cholera toxin with surface plasmon field-enhanced fluorescent spectroscopy

Seherler S., Bozdogan A., ÖZAL İLDENİZ T. A., Kök F. N., Anac Sakir I.

Biotechnology and Applied Biochemistry, vol.69, no.4, pp.1557-1566, 2022 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 69 Issue: 4
  • Publication Date: 2022
  • Doi Number: 10.1002/bab.2227
  • Journal Name: Biotechnology and Applied Biochemistry
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Applied Science & Technology Source, BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Compendex, Computer & Applied Sciences, EMBASE, Environment Index, Food Science & Technology Abstracts, INSPEC, MEDLINE, Veterinary Science Database
  • Page Numbers: pp.1557-1566
  • Keywords: antibody, biosensor, cholera toxin, environmental biotechnology, immobilization, surface plasmon resonance (SPR), surface plasmon field-enhanced fluorescent spectroscopy (SPFS), QUARTZ-CRYSTAL MICROBALANCE, VIBRIO-CHOLERAE, SENSITIVE DETECTION, RAPID DETECTION, FOOD SAFETY, RESONANCE, BIOSENSOR, WATER, IMMUNOSENSOR, PATHOGENS
  • Kocaeli University Affiliated: No

Abstract

© 2021 International Union of Biochemistry and Molecular Biology, Inc.In this work, a biosensor based on surface plasmon field-enhanced florescence spectroscopy (SPFS) method was successfully constructed to detect the truncated form of cholera toxin, that is, its beta subunit (CTX-B). CTX-B is a relatively small molecule (12 kDa) and it was chosen as model analyte for the detection of protein toxins originated from waterborne pathogens. Recognition layer was prepared on gold-coated LaSFN9 glasses modified with 11-mercaptoundecanoic acid (11-MUA). Biotin-conjugated anti-CTX-B polyclonal antibody (B-Ab) was immobilized on streptavidin (SA) layer constructed on the 11-MUA-modified surface. CTX-B amount was determined with direct assay using B-Ab in surface plasmon resonance (SPR) mode and with sandwich assay in SPFS mode using Cy5-conjugated anti-CTX-B polyclonal antibody. Minimum detected CTX-B concentrations were 10 and 0.01 μg/ml with SPR and SPFS, respectively, showing the sensitivity of the SPFS system over the conventional one. The detection was done in 2–6 h, which was faster than both culture and polymerase chain reaction (PCR)-based methods. Stability tests were performed with SA-coated sensors (excluding B-Ab). In this form, the layer was stable after 30 days of storage in phosphate-buffered saline (PBS; 0.01 M, pH = 7.4) at +4°C. B-Ab layer was formed immediately on them before each measurement.