CRET-based Multicolor Sensing Platform For Simultaneously And Sensitively Visualizing Multiple MiRNAs Related To Myocardial Infarction

MicroRNA(miRNA),is endogenously expressed non-coding RNA with a length of 18-23 nucleotides.Aberrant expressions of miRNAs are related to various cancers and other human diseases.Acute myocardial infarction(AMI)is the leading cause of high mortality from cardiovascular diseases.There are many miRNA markers related to it in serum.Therefore,accurate detection of miRNA is of important clinical significance for the early diagnosis and prognosis of AMI.However,most of the developed probes shows poor versatility and cannot be generalized for the detection of different miRNAs.In addition,the simultaneous detection of multiple miRNA markers remains a challenge.Therefore,the development of a highly versatile sensor platform that can simultaneously detect multiple miRNAs is not only helpful to reduce development costs,but also has important significance for improving the accuracy of disease diagnosis.Based on the above discussion,the work of this paper has developed a chemiluminescence multicolor sensing platform for the simultaneous visual and sensitive detection of multiple AMI-related circulating miRNAs.The main research content is divided into two parts:The first part mainly introduces the design and construction of general-purpose sensing probes.Based on the high versatility of the multicomponent nucleic acid enzyme(MNAzyme),a MNAzyme functionalized gold nanoparticle probe(MNAzyme@AuNP)was designed.The probe can not only achieve good signal amplification,but also the detection of different target miRNAs by simply modifying the recognition sequence of the probe,which exhibites the high versatility.A series of methods were used to characterize the preparation of probes,and the feasibility of miRNA-induced enzyme digestion amplification reaction was also studied.The second part mainly introduces the construction of chemiluminescence multicolor sensor platform and its application in simultaneous detection of multiple miRNAs.Spherical nucleic acid enzyme(SNAzyme)with high catalytic activity is produced by adding hemin to the above-mentioned cleavage product,which catalyzes the generation of strong chemiluminescence signals.A smartphone is used to image that.Two probes for miR-499 and miR-133a detection were prepared by simply modifying the probe recognition sequence.Simultaneous imaging detection of multiple miRNAs can be achieved by combining with the imaging array.In order to distinguish the light signals generated by different target miRNAs,fluorescein dye is simply added to the luminol-H2O2 reaction system,and the chemiluminescence resonance energy transfer(CRET)reaction is used to generate different colored light,which is beneficial to improve the resolution ability of the naked eye.The sensing platform can directly detect endogenous miRNA in serum at the same time,and give insight into the mechanism underlying the stability of circulating miR-16.Based on the above advantages,the constructed chemiluminescence multicolor sensing platform provides a new idea for the simultaneous detection of multiple miRNAs,and has great application potential in clinical accurate diagnosis and other aspects.