Non-Contact Temperature Control System Applicable to Polymerase Chain Reaction on a Lab-on-a-Disc

Abstract

Polymerase chain reaction (PCR) and the visual inspection of fluorescent amplicons for detection are commonly used procedures in nucleic acid tests. However, it has been extremely challenging to incorporate PCR onto a lab-on-a-disc (PCR–LOD) as it involves controlling the complicated and precise heating steps during thermal cycling and the measurement of reagent temperature. Additionally, a non-contact temperature control system without any connecting attachments needs to be implemented to facilitate the rotation of the PCR–LOD. This study presents a non-contact temperature control system to integrate conventional PCR onto an LOD. The experimental results demonstrate that our proposed system provides one-stop detection capabilities for Salmonella with a stable PCR amplification in a single PCR–LOD.

Fully Automated Lab-On-A-Disc Platform for Loop-Mediated Isothermal Amplification Using Micro-Carbon-Activated Cell Lysis

“…It blocks the pathway, but is easily opened when the laser beam is irradiated to hold the sample reagent in the cell-lysis chamber until the lysis proceeds. Laser valve 3, which is made of EVA (similar to the closing valve) and called the micro-EVA valve [ 26 ], was originally the channel of the cell-lysis chamber supernatant and LAMP preparation reagent to the amplification chamber. Before the LAMP heating was started (60 °C), laser valve 3 was closed using the laser module.…”

“…Inlet 2 is placed in the same shape on the right and left sides of the amplification chamber to inject UV adhesives into the UV blocking tape channel in both directions via the capillary effect. Both UV adhesives enforce the sealing strength of the following chambers: The cell lysis and DNA amplification chambers [ 26 , 27 ].…”

Recent advances and challenges in temperature monitoring and control in microfluidic devices

“…Therefore, it is possible to generate a constant and homogenous temperature distribution in the microfluidic device through this heating system. Other alternative methods employed for temperature control involve the use of a water bath [ 138 ], a laser [ 74 ], and a cement power resistor wrapped with conductive copper tape and aluminum foil, both using a fan as a cooling element.…”

“…Temperature control in microfluidics has been explored in applications, including cell culture [ 49 , 50 , 51 , 52 ], cell imaging [ 53 ], cell analysis [ 54 , 55 , 56 ], PCR [ 22 , 57 – 60 ], nucleic acid amplification test assays [ 61 ], microreactors [ 62 ], transparent electrodes [ 63 , 64 ], enzyme‐linked immunosorbent assay [ 44 ], biochemical synthesis [ 65 ], particle trapping [ 66 ], and microelectronic device cooling [ 67 ], among others [ 68 , 69 ]. For this, the use of microheaters [ 52 , 55 – 57 , 62 , 70 , 71 ], Peltier elements [ 25 , 58 , 59 , 72 ], two‐phase materials [ 73 ], laser beams [ 74 ], and cement power resistors [ 60 ] has been reported.…”

Automated multiplex nucleic acid tests for rapid detection of SARS-CoV-2, influenza A and B infection with direct reverse-transcription quantitative PCR (dirRT-qPCR) assay in a centrifugal microfluidic platform

“…30 Non-contact sensing and heating for temperature regulation has simplied the embedment of the microuidic disc onto spinning platform to support robust thermocycling without the need of complicated uidic actuation or heating-cooling electronic components. 31 This study primarily aims to provide an immediate solution to tackle both the current pandemic and a possible outbreak of inuenza in near future. To ensure a high degree of automation and lower risk of cross-contamination, we have designed and fabricated a microuidic platform and established the direct reverse-transcription quantitative PCR (dirRT-qPCR) assay on the microuidic platform for multiplex detection of SARS-CoV-2, inuenza A and B viruses in pharyngeal swab samples.…”