Watanabe K, Kuwata N, Sakamoto H, Amano Y, Satomura T, Suye SI. A smart DNA sensing system for detecting methicillin-resistant Staphylococcus aureus using modified nanoparticle probes.
Biosens Bioelectron 2014;
67:419-23. [PMID:
25223553 DOI:
10.1016/j.bios.2014.08.075]
[Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 08/09/2014] [Accepted: 08/27/2014] [Indexed: 11/18/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common causes of hospital-acquired infections. To prevent epidemics, a quick and simple detection method is required. In this study, we developed a novel electrochemical DNA detection method that does not rely upon polymerase chain reaction (PCR) and may be used in point-of-care facilities. The electrochemical DNA sensing system presented here is based on the chronoamperometric detection of ferrocene-labeled probes that were conjugated to gold nanoparticles (AuNPs). This DNA sensor system employed magnetic nanoparticle (MNP)-modified probes allowing easy sample DNA recovery. AuNP nanoparticles with ferrocene-labeled probes enabled the generation of an electric signal, and MNP/DNA/AuNP conjugates were formed by hybridization. Following hybridization, the MNP/DNA/AuNP hybridization complex is magnetically separated, and electrochemical current responses could be obtained because of the AuNP-ferrocene complexes. To construct a highly sensitive system, dye-linked L-proline dehydrogenase (L-proDH) was employed to amplify current responses following a catalytic reaction with L-proline. Rapid catalytic reaction of L-proDH and substrate was able to amplify the oxidation of ferrocene. Target DNA from MRSA could be quantified over a range of 10-166pM, and this sensing system could also distinguish MRSA from S. aureus.
Collapse