Rapid confirmation of five non-typhoidal Salmonella (NTS) serotypes using a low-cost portable-DIY OpenPCR© thermocycler

ABSTRACT

Aims@#OpenPCR is a low cost yet accurate thermocycler which can be self-built. The aim of the study is to highlight a low-cost alternative method for rapid confirmation of five predominant non-typhoidal Salmonella (NTS) serotypes using a multiplex PCR on a portable-DIY OpenPCR© thermocycler. @*Methodology and results@# Eight multiplex polymerase chain reaction (mPCR) samples containing genomic DNA of S. Agona selectively placed on the wells of the conventional PCR and OpenPCR© thermocyclers showed uniform heating in both thermocyclers. The limit of detection was similar for both thermocyclers for all five serotypes. The limit of detection for S. Typhimurium, S. Agona and S. Weltevreden was 10 pg/µL whereas the limit of detection for S. Enteriditis and S. Heidelberg was 1 pg/µL and 100 pg/µL, respectively. This assay incorporated a panel of unique genes; STM4495, SEN1392, SeHa-C4893, SeAg-B1096 and SENTW-3241 which were previously identified to be specific for S. Typhimurium, S. Enteritidis, S. Heidelberg, S. Agona, and S. Weltevreden, respectively, as well as the pan-Salmonella gene invA as internal control (IC) and pan-bacteria gene 16S rRNA to serve as amplification control (AC). The analytical specificity of the mPCR assay was found to be 100% for all five NTS using OpenPCR© thermocyclers. @*Conclusion, significance and impact of study@#The feasibility and low cost of the OpenPCR© thermocycler makes this device an ideal alternative for mPCR assay for rapid confirmation of NTS serotypes.