Yeom Dongsun, Kim Jeongtae, Kim Sungil, Ahn Sanghoon, Choi Jiyeon, Kim Youngwook, Koo Chiwan
Department of Electronic Engineering, Hanbat National University, Daejeon 34158, Korea.
Department of Laser and Electron Beam Application, Korea Institute of Machinery and Materials, Daejeon 34103, Korea.
Micromachines (Basel). 2022 Feb 21;13(2):339. doi: 10.3390/mi13020339.
This study proposes a rapid and inexpensive thermocycler that enables rapid heating of samples using a thin glass chip and a cheap chip resistor to overcome the on-site diagnostic limitations of polymerase chain reaction (PCR). Microchip PCR devices have emerged to miniaturize conventional PCR systems and reduce operation time and cost. In general, PCR microchips require a thin-film heater fabricated through a semiconductor process, which is a complicated process, resulting in high costs. Therefore, this investigation substituted a general chip resistor for a thin-film heater. The proposed thermocycler consists of a compact glass microchip of 12.5 mm × 12.5 mm × 2 mm that could hold a 2 μL PCR sample and a surface-mounted chip resistor of 6432 size (6.4 mm × 3.2 mm). Improving heat transfer from the chip resistor heater to the PCR reaction chamber in the microchip was accomplished via the design and fabrication of a three-dimensional chip structure using selective laser-induced etching, a rapid prototyping technique that allowed to be embedded. The fabricated PCR microchip was combined with a thermistor temperature sensor, a blower fan, and a microcontroller. The assembled thermocycler could heat the sample at a maximum rate of 28.8 °C/s per second. When compared with a commercially available PCR apparatus running the same PCR protocol, the total PCR operating time with a DNA sample was reduced by about 20%.
本研究提出了一种快速且廉价的热循环仪，该热循环仪能够使用薄玻璃芯片和廉价的片式电阻器对样品进行快速加热，以克服聚合酶链反应（PCR）现场诊断的局限性。微芯片PCR设备已出现，旨在使传统PCR系统小型化，并减少操作时间和成本。一般来说，PCR微芯片需要通过半导体工艺制造的薄膜加热器，这是一个复杂的过程，导致成本高昂。因此，本研究用普通片式电阻器替代了薄膜加热器。所提出的热循环仪由一个12.5毫米×12.5毫米×2毫米的紧凑型玻璃微芯片和一个6432尺寸（6.4毫米×3.2毫米）的表面贴装片式电阻器组成，该玻璃微芯片可容纳2微升PCR样品。通过使用选择性激光诱导蚀刻（一种允许嵌入的快速成型技术）设计和制造三维芯片结构，实现了从片式电阻器加热器到微芯片中PCR反应腔的传热改善。制造的PCR微芯片与热敏电阻温度传感器、鼓风机和微控制器相结合。组装好的热循环仪能够以每秒最高达28.8℃的速率加热样品。与运行相同PCR协议的市售PCR仪器相比，使用DNA样品时总的PCR操作时间减少了约20%。
