Toward a Rapid, Integrated, and Fully Automated DNA Diagnostic Assay for Chlamydia trachomatis and Neisseria gonorrhoeae

摘要

Molecular testing for the diagnosis of bacterial or viral infections in raw clinical specimens requires complex, multistep procedures to release and isolate nucleic acid before PCR amplification (1)(2). Laboratory bench-top sample preparation procedures are very labor- and equipment-intensive, which reflects on total assay cost and increased susceptibility to sample and reagent carryover (3)(4). The need for automation has led to the development and introduction of robotics-based laboratory instruments with discrete operations that simulate the basic functions of a laboratory technician. These systems are typically developed for high-throughput applications and usually require intermittent operator involvement. In addition, because they directly emulate the operator’s manual functions for processing boluses of sample and reagents, the issue of sample or reagent carryover and carryin remains unresolved, and the complexity of the robotic mechanisms themselves contributes to high capital costs and poor reliability. Several factors currently contribute to and facilitate the development of the next generation of automated and integrated diagnostics instruments. One factor includes the recent advances in the microfluidics field of miniaturized integrated platforms and supporting technologies, which potentially enable the seamless execution of a sequence of protocols (5). Miniaturized processor-controlled microfluidic platforms contain chambers and valves, and encapsulate entities such as filter membranes or solid-phase particles. They are able to execute important processes such as cell capture, lysis, and fluid mixing, which currently require discrete laboratory instruments (6). Another factor is the development of a miniature, rapid PCR thermocycler device with real-time optical detection capable of multiplex analysis (7)(8)(9). Its modularity and adaptability allows for easy integration into an instrument platform downstream of a sample preparation module. It is possible to envision a one-step operation covering sample preparation and analysis, from raw sample to results reporting. Finally, the utilization of …