Design and synthesis of DNA hydrogel based on EXPAR and CRISPR/Cas14a for ultrasensitive detection of creatine kinase MB

• DOI: 10.1016/j.bios.2022.114792
• Publication Date: 2022-10-08T06:04:22Z
• Authors: Mengmeng Chen; Jingyang Zhang; Yuan Peng; Jialei Bai; Shuang Li; Dianpeng Han; Shuyue Ren; Kang Qin; Huanying Zhou; Tie Han; Yu Wang; Zhixian Gao
• Keywords: Isoenzymes; 0301 basic medicine; 03 medical and health sciences; DNA, Complementary; Creatine Kinase, MB Form; Hydrogels; Biosensing Techniques; DNA; CRISPR-Cas Systems; Biomarkers

Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas systems exhibit significant potential in developing biosensing technology due to their collateral cleavage capabilities. Herein, we introduced the collateral cleavage activity of CRISPR/Cas14a to activate DNA hydrogel for ultrasensitive detection of the myocardial infarction biomarker creatine kinase MB (CK-MB). In this strategy, the designed CRISPR/Cas14a system can be activated by introducing complementary DNA (cDNA) derived from competitive dissociation and exponential amplification (EXPAR), which is positively correlated with creatine kinase isoenzyme (CK-MB) concentration. Then the activated Cas14a protein can be utilized to indiscriminately cleave the DNA hydrogel cross-linker strand, leading to the degradation of the gel matrix and thus releasing the pre-encapsulated PtNPs/Cu-TCPP(Fe). PtNPs/Cu-TCPP(Fe) can trigger the TMB reaction, leading to an increase in absorbance value at 450 nm, thus enabling the quantitative detection of CK-MB. The proposed strategy combines CRISPR/Cas14a with DNA hydrogel for the first time, improving the programmability of DNA hydrogel and providing a reliable, sensitive, and versatile detection platform for trace non-nucleic acid targets.