電気通信システムと管理

The utilization of laser-induced nucleic acid amplification reaction on the surface of composite magnetic nanoparticles for rapid and semi-quantitative genes detection

Abstract

Pin-Kuan Yeh

Nucleic acid testing (NAT) is regarded as a highly sensitive and specific method for infectious disease screening. Among NAT technologies, polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) are two common technologies in fundamental research and clinical applications for nuclei acid amplification, which the targeted genes at accurate thermal- control conditions. However, while implementing these two technologies in the external heater (e.g., PCR machine), indirect heat transfer not only leads to massive amounts of energy consumption but increases the cost of assembling a complicated and huge-volume thermal-control system. Therefore, a stable and direct internal thermal-control system is urgent to be developed for NAT. This study combined photo-thermal nanoparticles with LAMP technology, termed as photo- LAMP, which achieved a rapid semi-quantitative detection of Mycobacterium tuberculosis (MTB) bacteria nucleic acids. In this system, a set of six biotin-labeled primers was selected for targeting 16S rRNA gene of MTB bacteria, conjugated to the surface of photo-thermal nanoparticles through streptavidin-biotin interaction. Polypyrrole-modified iron oxide nanoparticles (i.e., photo- thermal nanoparticles) were utilized to be an internal heater for cell or bacteria lysis, maintained a suitable temperature for LAMP reaction and made fluorescent signal condense. Owing to magnetic properties of nanoparticles, the fluorescent intensity was enhanced by magnet. The results showed that photo-LAMP system was capable of semi-quantitatively detecting the targeted nucleic acids within 20 minutes and had lower limit of detection (LoD) than that of conventional PCR machine.