Sample preparation is a leading bottleneck in rapid detection of pathogenic bacteria. Here, we use Lyse-It® for bacterial cellular lysis, genomic DNA fragmentation, and protein release and degradation for both Listeria monocytogenes and Vibrio cholerae. The concept of Lyse-It® employs a conventional microwave and Lyse-It® slides for intensely focused microwave irradiation onto the sample. High microwave power and a <60 second irradiation time allow for rapid cellular lysis and subsequent intracellular component release. The pathogenic bacteria are identified by quantitative polymerase chain reaction (qPCR), which subsequently demonstrates the viability of DNA for amplification post microwave-induced lysis. Intracellular component release, degradation, and detection of L. monocytogenes and V. cholerae has been performed and shown in this paper. These results demonstrate a rapid, low-cost, and efficient way for bacterial sample preparation on both food and water-borne Gram-positive and -negative organisms alike.

Nucleic acid-based detection of gonorrhea infections typically require a two-step process involving isolation of the nucleic acid, followed by the detection of the genomic target often involving PCR-based approaches. In an effort to improve on current detection approaches, we have developed a unique two-step microwave-accelerated approach for rapid extraction and detection of Neisseria gonorrhoeae (GC) DNA. Our approach is based on the use of highly-focused microwave radiation to rapidly lyse bacterial cells, release, and subsequently fragment microbial DNA. The DNA target is then detected by a process known as microwave-accelerated metal-enhanced fluorescence (MAMEF), an ultra-sensitive direct DNA detection analytical technique. In the present study, we show that highly focused microwaves at 2.45 GHz, using 12.3 mm gold film equilateral triangles, are able to rapidly lyse both bacteria cells and fragment DNA in a time- and microwave power-dependent manner. Detection of the extracted DNA can be performed by MAMEF, without the need for DNA amplification in less than 10 minutes total time or by other PCR-based approaches. Collectively, the use of a microwave-accelerated method for the release and detection of DNA represents a significant step forward towards the development of a point-of-care (POC) platform for detection of gonorrhea infections.

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