Polymerase Chain Reaction Device Research Articles

A Thermocycler Using a Chip Resistor Heater and a Glass Microchip for a Portable and Rapid Microchip-Based PCR Device.

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%.

Rapid membrane-based photothermal PCR for disease detection

The worldwide incidence of deadly infectious diseases has increased in recent years. Therefore, a rapid and accurate nucleic acid diagnostic system is in high demand. Polymerase chain reaction (PCR) is the standard method for amplifying and quantifying nucleic acid biomarkers for disease detection. Although several rapid PCR systems have been developed to overcome the limitations of conventional PCR, such as post-processing for analysis, complicated handling, and highly specialized instruments, a new PCR testing approach is still required. In this study, we developed a rapid membrane-based photothermal PCR that enables quantitative fluorescence detection. It requires no post-PCR procedures and provides user-friendly micro-scale solution control and sample loading. Au nanostructure was deposited on the reaction pad as a light-to-heat converter for PCR thermocycling. The automatically controlled 785 nm light source heated a solution in the reaction pad with photothermal effect. The temperature of the reaction solution, which was absorbed in a membrane, was cycled 25 times between 63 °C and 95 °C within 6 min with a photothermal cycler. The amplified samples on the membrane were then quantitatively analyzed by measuring the fluorescence signal of intercalating SYBR dye within 12 min. DNA samples extracted from Staphylococcus aureus and unpurified cells were amplified and analyzed. This membrane-based PCR approach can provide easy connectivity with various membrane-based sample pre-treatment processes, and therefore the proposed procedure could be used as the basis for an all-in-one molecular diagnosis platform. This simple, rapid, and sensitive PCR device could also serve as the basis for advanced molecular diagnostics.

Miniaturized and IoT Enabled Continuous-Flow-Based Microfluidic PCR Device for DNA Amplification.

Herein, a continuous-flow driven microfluidic device has been designed and fabricated using the CO2 laser ablation method for polymerase chain reaction (PCR). The device consists of a polymethyl methacrylate (PMMA) microfluidic channel with 30 serpentine thermal cycles, an arduino board, two custom-made cartridge heaters, and thermocouple sensors. The portable thermal management system, with aluminium blocks placed on a wooden substrate, working on the PID controller principle, is low-cost, battery-powered, automated, integrated, and IoT-enabled. The device with dimensions 80×72×36 mm3 (L × W × H) has a temperature accuracy of ±0.2 °C. The IoT module enables accessing and storage of real-time temperature values directly onto the smartphone through ThingSpeak analytics. It was developed to achieve desirable accurate temperature at two thermal zones, denaturation and annealing (95 °C and 60 °C) on the microfluidic thermal management platform. A PCR mixture of [Formula: see text] was infused into the serpentine-based microchannel using a syringe pump. Amplification of DNA template with 594-base pair (bp) fragment of the rat GAPDH gene was successfully performed on the miniaturized thermal management system. The total time required for a complete PCR reaction was 32 min at an optimum flow rate of [Formula: see text]/min. The amplified sample of the target DNA obtained from the PCR microchannel was then separated by agarose gel electrophoresis and was further analyzed using a gel-doc system. Finally, the obtained results were compared to the conventional PCR instrument showing excellent performance.

A plasmonic gold nanofilm-based microfluidic chip for rapid and inexpensive droplet-based photonic PCR

Polymerase chain reaction (PCR) is a powerful tool for nucleic acid amplification and quantification. However, long thermocycling time is a major limitation of the commercial PCR devices in the point-of-care (POC). Herein, we have developed a rapid droplet-based photonic PCR (dpPCR) system, including a gold (Au) nanofilm-based microfluidic chip and a plasmonic photothermal cycler. The chip is fabricated by adding mineral oil to uncured polydimethylsiloxane (PDMS) to suppress droplet evaporation in PDMS microfluidic chips during PCR thermocycling. A PDMS to gold bonding technique using a double-sided adhesive tape is applied to enhance the bonding strength between the oil-added PDMS and the gold nanofilm. Moreover, the gold nanofilm excited by two light-emitting diodes (LEDs) from the top and bottom sides of the chip provides fast heating of the PCR sample to 230 °C within 100 s. Such a design enables 30 thermal cycles from 60 to 95 °C within 13 min with the average heating and cooling rates of 7.37 ± 0.27 °C/s and 1.91 ± 0.03 °C/s, respectively. The experimental results demonstrate successful PCR amplification of the alcohol oxidase (AOX) gene using the rapid plasmonic photothermal cycler and exhibit the great performance of the microfluidic chip for droplet-based PCR.

A straight-forward, inexpensive, low power continuous-flow µPCR chip using PCB-based heater electrodes with uniform temperature distribution

A relatively high-efficiency, two-step type continuous flow microfluidic device for polymerase chain reaction (PCR) is presented in this work. The heater electrodes are designed and fabricated based on 0.25 µm-thick two-layer standard printed circuit board (PCB) technology. Temperature uniformity in different temperature zones of PCR plays a key role in increasing process efficiency. By properly designing meander shaped electrodes, relatively good temperature uniformity and high PCR efficiency is realized. A symmetrical structure is demonstrated for the arrangement of the electrodes, where the annealing electrode is placed between two denaturation electrodes. In this way, we have favorably used the thermal cross talk between the two temperature zones in order to create a relatively uniform temperature in the annealing electrode. Heat spreaders between meander lines in denaturation electrodes are used to distribute temperature uniformly, in contrast to the literature, where complex optimization methods are adopted. This eliminates the need to use bulky heat spreaders such as copper or aluminum blocks which are commonly used to uniformize temperature in continuous flow µPCRs. As a result, the number of components and the overall size of the device and consequently the complexity and fabrication cost decreases. On the other hand, the thermal mass is reduced, which in turn reduces the power consumption of the system. The temperature measurements are first performed with contact PT100 temperature sensors and then the results are verified by a thermal camera. The temperature difference measured by PT100 sensors approximately matches the standard deviation obtained from the thermal camera in a specific area. For the denaturation electrode these values are 1.14 °C and 1.2 °C, respectively. A maximum absolute temperature difference of 1 °C is measured for the annealing electrode. The fabricated microchip with dimensions of 50 mm × 40 mm is tested by an 88 base-pair DNA sample from the human housekeeping gene with a power consumption of less than 0.82 W. A relatively remarkable amplification efficiency is achieved to prove the efficacy of our inexpensive PCB electrodes.

Virtual Fluorescence Color Channels by Selective Photobleaching in Digital PCR Applied to the Quantification of KRAS Point Mutations

Multiplexing of analyses is essential to reduce sample and reagent consumption in applications with large target panels. In applications such as cancer diagnostics, the required degree of multiplexing often exceeds the number of available fluorescence channels in polymerase chain reaction (PCR) devices. The combination of photobleaching-sensitive and photobleaching-resistant fluorophores of the same color can boost the degree of multiplexing by a factor of 2 per channel. The only additional hardware required to create virtual fluorescence color channels is a low-cost light-emitting diode (LED) setup for selective photobleaching. Here, we present an assay concept for fluorescence color multiplexing in up to 10 channels (five standard channels plus five virtual channels) using the mediator probe PCR with universal reporter (UR) fluorogenic oligonucleotides. We evaluate the photobleaching characteristic of 21 URs, which cover the whole spectral range from blue to crimson. This comprehensive UR data set is employed to demonstrate the use of three virtual channels in addition to the three standard channels of a commercial dPCR device (blue, green, and red) targeting cancer-associated point mutations (KRAS G12D and G12V). Moreover, a LOD (limit of detection) analysis of this assay confirms the high sensitivity of the multiplexing method (KRAS G12D: 16 DNA copies/reaction in the standard red channel and KRAS G12V: nine DNA copies/reaction in the virtual red channel). Based on the presented data set, optimal fluorogenic reporter combinations can be easily selected for the application-specific creation of virtual channels, enabling a high degree of multiplexing at low optical and technical effort.

Automated optimization of double heater convective polymerase chain reaction devices based on CFD simulation database and artificial neural network model.

This paper presents a framework for automated optimization of double-heater convective PCR (DH-cPCR) devices by developing a computational fluid dynamics (CFD) simulation database and artificial neural network (ANN) model. The optimization parameter space that includes the capillary tube geometries and the heater sizes of DH-cPCR is established, and a database consisting of nearly 10,000 CFD simulations is constructed. The database is then used to train a two-stage ANN models that select practically relevant data for modeling and predict PCR device performance. The trained ANN model is then combined with the gradient-based and the heuristics optimization approaches to search for optimal device configuration that possesses the shortest DNA doubling time. The entire design process including model meshing and configuration, parallel CFD computation, database organization, and ANN training and utilization is fully automated. Case studies confirm that the proposed framework can successfully find the optimal device configuration with an error of less than 0.3 s, and hence, representing a cost-effective and rapid solution of DH-cPCR device design.

Deskilled and Rapid Drug-Resistant Gene Detection by Centrifugal Force-Assisted Thermal Convection PCR Device.

Here we report the improved Cyclo olefin polymer (COP) microfluidic chip and polymerase chain reaction (PCR) amplification system for point-of-care testing (POCT) in rapid detection of Carbapenem-resistant Enterobacteriaceae (CRE). The PCR solution and thermal cycling is controlled by the relative gravitational acceleration (7G) only and is expected to pose minimal problem in operation by non-expert users. Detection is based on identifying the presence of carbapenemase encoding gene through the corresponding fluorescence signal after amplification. For preliminary tests, the device has been demonstrated to detect blaIMP-6 from patients stool samples. From the prepared samples, 96.4 fg/µL was detected with good certainty within 15 min (~106 thermocycles,) which is significantly faster than the conventional culture plate method. Moreover, the device is expected to detect other target genes in parallel as determination of the presence of blaNDM-1 and blaOXA-23 from control samples has also been demonstrated. With the rising threat of drug-resistant bacteria in global healthcare, this technology can greatly aid the health sector by enabling the appropriate use of antibiotics, accelerating the treatment of carriers, and suppressing the spread.

Usefulness of a newly developed high-speed polymerase chain reaction analysis system for the diagnosis of Clostridioides difficile infection

IntroductionThe incidence of Clostridioides difficile infection (CDI) has been continuously increasing and thereby became an important issue worldwide. Appropriate diagnosis, management, and infection control are required for patients with CDI. Enzyme immunoassay (EIA) is a widely used standard diagnostic tool for C. difficile-specific glutamate dehydrogenase (GDH) and C. difficile toxins (toxins A and B). However, the sensitivity of EIA in detecting C. difficile toxins has been reported to be relatively low, resulting in CDI underdiagnosis. Therefore, nucleic acid amplification tests (NAAT) are recently developed for higher sensitivity/specificity test. MethodsIn this study, a total of 279 stool samples submitted for CDI diagnosis were examined using an independently developed new high-speed polymerase chain reaction (PCR) device (PathOC RightGene, Metaboscreen). In parallel, results were compared with those of definitive diagnosis and conventional diagnostic methods (EIA, real-time PCR) to assess the inspection accuracy. ResultsPathOC RightGene showed high sensitivity (96.7%) and specificity (96.7%). Regarding the measurement time, C. difficile-specific and C. difficile toxin genes were simultaneously detected in approximately 25 min for one sample (including the preprocessing and measurement time). ConclusionPathOC RightGene has been found to show both excellent sensitivity and rapidity and thus can be used for the reliable and early diagnosis, which are needed for the appropriate management of CDI.

Plasmonic and label-free real-time quantitative PCR for point-of-care diagnostics.

In response to the world's medical community's need for accurate and immediate infectious pathogen detection, many researchers have focused on adapting the standard molecular diagnostic method of polymerase chain reaction (PCR) for point-of-care (POC) applications. PCR technology is not without its shortcomings; current platforms can be bulky, slow, and power-intensive. Although there have been some advances in microfluidic PCR devices, a simple-to-operate and fabricate PCR device is still lacking. In the first part of this paper, we introduce a compact plasmonic PCR thermocycler in which fast DNA amplification is derived from efficient photothermal heating of a colloidal reaction mixture containing gold nanorods (AuNRs) using a small-scale vertical-cavity surface-emitting laser (VCSEL). Using this method, we demonstrate 30 cycle-assay time of sub-ten minutes for successful Chlamydia trachomatis DNA amplification in 20 μL total PCR sample volume. In the second part, we report an ultrasensitive real-time amplicon detection strategy which is based on cycle-by-cycle monitoring of 260 nm absorption of the PCR sample. This was accomplished by irradiating the PCR sample using a UV LED and collecting the transmitted optical power with a photodetector. The UV absorption dependency on the nucleotides' structural degree of freedom gives rise to distinctive features in the shape of UV amplification curves for the determination of PCR results, thus circumventing the need for the complicated design of target-specific probes or intercalating fluorophores. This amplicon quantification method has a high detection sensitivity of one DNA copy. This is the first demonstration of a compact plasmonic thermocycler combined with a real-time fluorophore-free quantitative amplicon detection system. The small footprint of our PCR device stems from hardware miniaturization, while abundant sample volume facilitates highly sensitive detection and fluid handling required for in-field sample analysis, thereby making it an excellent candidate for POC molecular diagnostics.

Optimisation of microfluidic polymerase chain reaction devices

The invention and development of Polymerase Chain Reaction (PCR) technology have revolutionised molecular biology and molecular diagnostics. There is an urgent need to optimise the performance of these devices while reducing the total construction and operation costs. This study proposes a CFD-enabled optimisation methodology for continuous flow (CF) PCR devices with serpentine-channel structure, which enables the optimisation of DNA amplification efficiency and pressure drop to be explored while varying the width (W) and height (H) of the microfluidic (μ) channel. This is achieved by using a surrogate-enabled optimisation approach accounting for the geometrical features of a μCFPCR device by performing a series of simulations using COMSOL Multiphysics 5.4®. The values of the objectives are extracted from the CFD solutions, and the response surfaces are created using polyharmonic splines. Genetic algorithms are then used to locate the optimum design parameters. The results indicate that there is the possibility of improving the DNA concentration and the pressure drop in a PCR cycle by ~2.1 % ([W, H] = [400 μm, 50 μm]) and ~95.2 % ([W, H] = [400 μm, 80 μm]) respectively, by modifying its geometry.

Miniaturized Thermal Monitoring Module With CO₂ Laser Ablated Microfluidic Device for Electrochemically Validated DNA Amplification

Polymerase chain reaction (PCR) is the gold standard method to amplify deoxyribonucleic acid (DNA) fragments. Several methods have been used to miniaturize and integrate PCR to execute in a microfluidic platform. A continuous-flow-based microfluidic PCR device permits the required rapid thermal cycling and multiplexing, which are hard to realize in a benchtop PCR or microchamber PCR. This work aims to develop a microfluidic PCR platform using a custom-made Internet of Things (IoT)-enabled portable thermal monitoring module. The microfluidic device was fabricated on polymethyl methacrylate (PMMA) using a CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> laser. Apart from 30 serpentine cycles, the PCR microchannel also had initial denaturation and final elongation regions to enhance the overall amplification. As a proof-of-application, rat GAPDH gene, with a fragment size of 594 base pair, has been amplified on the miniaturized platform. Furthermore, the agarose gel electrophoresis technique was used to separate the DNA molecules validated using a gel-doc system. Subsequently, the acquired results were quantitatively compared with the conventional thermocycler using ImageJ software. Furthermore, this was also validated with electrochemical DNA detection using differential pulse voltammetry (DPV). The results from the smart low-power device showed promising performance for the nucleic acid amplification process while reducing the overall amplification time and achieving benchmarked efficiency.

Improvement of Heat Sink Effect Using Zinc Oxide Nanostructure.

Heat sinks that dissipate heat effectively play a significant role in devices with high-precision temperature control, such as thermal cyclers for polymerase chain reaction (PCR). This study was carried out to develop a heat sink with a high thermal conductivity to dissipate heat effectively. To increase the surface area of the heat sink, zinc oxide (ZnO) nanostructures were fabricated on an aluminum plate. ZnO nanostructures were fabricated by hydrothermal method and confirmed by scanning electron microscopy and X-ray diffraction. With the increase in the concentration of the precursors, the length of the nanorods increased, and with longer reaction time, nanostructures connected with higher stability and larger surface area. Thermal conductivity is increased by ZnO nanostructures and is affected by the concentration of precursors and the reaction time. Thermal conductivity of an optimal ZnO-coated Al plate is 2 times higher than that of a bare one. This technology can be applied to portable PCR devices to reduce weight, size, and power consumption.

Rapid detection assay of toxigenic Clostridioides difficile through PathOC RightGene, a novel high-speed polymerase chain reaction device

Nucleic acid amplification tests for diagnosing Clostridioides difficile infections (CDI) are improving to become faster and more accurate. This study aimed to evaluate the accuracy of rapid detection of toxigenic C. difficile using the novel high-speed polymerase chain reaction (PCR) device, PathOC RightGene. These results were compared and evaluated with real-time PCR (qPCR) and enzyme immunoassays (EIA) kit. For this study, 102 C. difficile and 3 Clostridium species isolated from CDI patients were used. These C. difficile isolates were 85 toxigenic and 17 non-toxigenic strains. The results of qPCR served as a standard, and sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the PathOC Right Gene were 99.2%, 99.4%, 100%, 98.8%, and 99.3%, respectively. Turnaround time of qPCR and EIA was 85 and 30 minutes, whereas PathOC RightGene was only 25 minutes including DNA extraction. This novel high-speed PCR device detected toxigenic C. difficile rapidly and accurately.

Surrogate- and possibility-based design optimization for convective polymerase chain reaction devices

This paper presents a surrogate- and possibility-based design optimization (SPBDO) methodology for robust design of convective PCR. Parametric computational fluid dynamics (CFD) models are built and simulated at sampled locations within the design space to capture the effect of design configurations on thermofluidic transport and convection–diffusion-reaction in the convective PCR. A support vector machine-based classifier model is trained to retain only practically relevant data for enhanced surrogate modeling accuracy. Surrogate models are constructed by Kriging interpolation and multivariate polynomial regression methods to establish the mapping between design configurations and DNA doubling time (indicative of reactor performance). Then a process to combine the sequential method of PBDO and the surrogate model is developed, and a trade study is carried out to evaluate the impact of possibility of failure ( $$\alpha$$ -value) and the balance between performance and design reliability. Our study demonstrates that the proposed SPBDO represents an effective method to consider robustness in PCR design for POC applications, especially when the uncertainty information or possibilistic characteristics of design variables is limited.

Elevating Chemistry Research with a Modern Electronics Toolkit

With the rapid development of high technology, chemical science is not as it used to be a century ago. Many chemists acquire and utilize skills that are well beyond the traditional definition of chemistry. The digital age has transformed chemistry laboratories. One aspect of this transformation is the progressing implementation of electronics and computer science in chemistry research. In the past decade, numerous chemistry-oriented studies have benefited from the implementation of electronic modules, including microcontroller boards (MCBs), single-board computers (SBCs), professional grade control and data acquisition systems, as well as field-programmable gate arrays (FPGAs). In particular, MCBs and SBCs provide good value for money. The application areas for electronic modules in chemistry research include construction of simple detection systems based on spectrophotometry and spectrofluorometry principles, customizing laboratory devices for automation of common laboratory practices, control of reaction systems (batch- and flow-based), extraction systems, chromatographic and electrophoretic systems, microfluidic systems (classical and nonclassical), custom-built polymerase chain reaction devices, gas-phase analyte detection systems, chemical robots and drones, construction of FPGA-based imaging systems, and the Internet-of-Chemical-Things. The technology is easy to handle, and many chemists have managed to train themselves in its implementation. The only major obstacle in its implementation is probably one's imagination.

Fully automatic integrated continuous-flow digital PCR device for absolute DNA quantification

Existing digital polymerase chain reaction (PCR) devices consist of multiple independent devices, such as a droplet generator, a PCR thermocycler, and a droplet reader, which have the disadvantages of low integration, complex equipment structure, and high operation difficulty. This paper proposes a fully automatic integrated digital PCR device based on continuous-flow digital PCR theory. By simply adding the sample to the entrance of the integrated instrument, a series of procedures required for digital PCR detection can be fully automated, including sample injection, droplet generation, PCR thermal cycling, fluorescence acquisition, and signal analysis. In contrast to traditional techniques, sample testing requires only one integrated device rather than three separate instruments. For full automation, we design complete control and data processing software, which can complete a test by one-step operation. Therefore, the disadvantages of traditional instruments, such as multi-step operation, and hence, potential environmental pollution, are avoided. Moreover, the system can be powered by solar cells and does not require an external power supply.As a proof of concept, the proposed device is used for absolute quantitative detection of the hepatitis B virus in serum samples. The capacity of the system is validated by absolute quantification of three orders of magnitude from 103 to 105 IU/mL. The results have a good linear correlation (0.9986) with those of the traditional quantitative (qPCR), thus confirming the reliability of the instrument. In summary, we believe that our work can promote the development of integrated digital PCR systems.

Portable and Battery-Powered PCR Device for DNA Amplification and Fluorescence Detection.

Polymerase chain reaction (PCR) is a technique for nucleic acid amplification, which has been widely used in molecular biology. Owing to the limitations such as large size, high power consumption, and complicated operation, PCR is only used in hospitals or research institutions. To meet the requirements of portable applications, we developed a fast, battery-powered, portable device for PCR amplification and end-point detection. The device consisted of a PCR thermal control system, PCR reaction chip, and fluorescence detection system. The PCR thermal control system was formed by a thermal control chip and external drive circuits. Thin-film heaters and resistance temperature detectors (RTDs) were fabricated on the thermal control chip and were regulated with external drive circuits. The average heating rate was 32 °C/s and the average cooling rate was 7.5 °C/s. The disposable reaction chips were fabricated using a silicon substrate, silicone rubber, and quartz plate. The fluorescence detection system consisted a complementary metal-oxide-semiconductor (CMOS) camera, an LED, and mirror units. The device was driven by a 24 V Li-ion battery. We amplified HPV16E6 genomic DNA using our device and achieved satisfactory results.

Numerical method for optimization of thermal cycling in 3D-printed polymerase chain reaction device

A continuous-flow polymerase chain reaction (PCR) device with integrated heaters for DNA amplification was studied. We developed a numerical model to predict the temperature variations of a 3D-printed PCR device for different heater temperatures. The target temperatures at thermal zones for a successful PCR are 95 °C, 55 °C, and 72 °C for denaturation, annealing and extension, respectively. A numerical simulation was conducted to determine the heater temperatures required to compensate for heat loss. Our numerical model and optimization method were confirmed by comparison with the experimental results. Consequently, the compensated heater temperatures required to achieve the target temperatures are 97.9 °C, 56.6 °C and 74.1 °C. The proposed optimization method and numerical simulations will be useful in achieving highly effective thermal cycling in the 3D-printed PCR device.

Design and Implementation of Polymerase Chain Reaction Device for Aptamers Selection of Tumor Cells.

Nucleic acid aptamers are a kind of one-dimensional biological nanomaterials and have found many applications. This paper designed and implemented a polymerase chain reaction (PCR) amplification device with a reaction volume of 500 μL, which can be used for the amplification of nucleic acid aptamers of tumor cells in the aptamer selection. This device mainly includes a control module, a temperature measuring module, a PCR amplification tube, a metal tank module, a liquid crystal display (LCD) and operation module and a cooling module. The new PCR amplification chamber is matched with the designed metal tank to ensure the temperature uniformity of the PCR amplification solution. The control module based on the STM32F103RCT6 manages the workflow of the entire device. The PCR amplification chamber and PT100 sensors on the metal tank formed a closed-loop feedback system, and the incremental proportional-integral-derivative (PID) algorithm was used to achieve the precise temperature control. In addition, we introduced the Smith predictive compensation algorithm to solve the temperature hysteresis problem of the PCR amplification chamber. The experimental results showed that the PCR device can meet the requirements for the nucleic acid aptamer selection of tumor cells. The device can also be used in other experiments with large-volume PCR amplification.