Label-free impedimetric biosensor for Salmonella T. detection based on pyrrole (pyrrole -3-carboxyl acid) copolymer supported aptamer.
2016 (English)In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 80, 194-200 p.Article in journal (Refereed) Published
The Gram-negative bacterium, Salmonella Typhimurium (S. Typhimurium) is a food borne pathogen responsible for numerous hospitalisations and deaths all over the world. Conventional detection methods for pathogens are time consuming and labour-intensive. Hence, there is considerable interest in faster and simpler detection methods. Polypyrrole-based polymers, due to their intrinsic chemical and electrical properties, have been demonstrated to be valuable candidates for the fabrication of chemo/biosensors and functional surfaces. Similarly aptamers have been shown to be good alternatives to antibodies in the development of affinity biosensors. In this study, we report on the combination of poly [pyrrole-co-3-carboxyl-pyrrole] copolymer and aptamer for the development of a label-less electrochemical biosensor suitable for the detection of S. Typhimurium. Impedimetric measurements were facilitated by the effect of the aptamer/target interaction on the intrinsic conjugation of the poly [pyrrole-co-3-carboxyl-pyrrole] copolymer and subsequently on its electrical properties. The aptasensor detected S. Typhimurium in the concentration range 10(2)-10(8)CFUmL(-1) with high selectivity over other model pathogens and with a limit of quantification (LOQ) of 100CFUmL(-1) and a limit of detection (LOD) of 3CFUmL(-1). The suitability of the aptasensor for real sample detection was demonstrated via recovery studies performed in spiked apple juice samples. We envisage this to be a viable approach for the inexpensive and rapid detection of pathogens in food, and possibly in other environmental samples.
Place, publisher, year, edition, pages
2016. Vol. 80, 194-200 p.
Aptamer; Electrochemical impedance spectroscopy; Label-free detection; Poly [pyrrole-co-3-carboxyl-pyrrole]; S. Typhimurium
IdentifiersURN: urn:nbn:se:liu:diva-128193DOI: 10.1016/j.bios.2016.01.057PubMedID: 26836649OAI: oai:DiVA.org:liu-128193DiVA: diva2:929987
FunderSwedish Research Council