Suzhou Institute of Medical Engineering, Chinese Academy of Sciences: Progress has been made in the research of paper-based distance sensor
The traditional miRNA detection techniques mainly include Northern blotting, real-time quantitative reverse transcription PCR, microarray chip method, sequencing, etc. However, there are some inherent shortcomings or deficiencies. As a widely used natural polymer material, paper has many characteristics such as low cost, high flexibility, good portability and biodegradation.. As a new type of point-of-care detection (POCT) device, paper-based distance sensor is designed around the functionalization of paper-based materials, and performs qualitative or quantitative analysis according to the observable distance signal generated by the trigger reaction of the target to be measured. It has the advantages of intuitive reading and easy operation.
Recently, Miao Peng's research group in Suzhou Institute of Medical Engineering developed a paper based distance sensor based on programmable DNA hydrogel combined with chain displacement strategy. As shown in Figure 1, the chain replacement polymerization triggered by the target miRNA produces a large amount of single-stranded DNA that is used to hybridize with another sequence and assist in the assembly of DNA hydrogels.The infiltration distance of the system on the paper base strip can be used to reflect the concentration of the target miRNA. The formation and reaction parameters of DNA hydrogel were verified and optimized by using the thrombus elastography instrument independently developed by Suzhou Institute of Medical Engineering.The change of flow distance on the paper based sensor channel is closely related to the viscosity (assembly degree) of DNA hydrogel. According to the mathematical model of reaction solution flowing along the strip, the channel width, sample amount, reaction time and the preparation conditions of DNA hydrogel of the paper based sensor were comprehensively optimized.Under the corresponding experimental parameters, miRNA quantification, selectivity testing, and clinical sample testing were conducted, and the corresponding results were highly consistent with those obtained by real-time quantitative reverse transcription PCR.
This method not only has high sensitivity, but also has advantages such as easy operation and low cost, which can meet the requirements of real-time detection. It has shown great potential in biological research and clinical disease diagnosis.
Source: Sensor Expert Network