Electrochemical analysis of Ca2+ based on DNAzyme catalyzed degradation of DNA hydrogel

• Published in: Electrochemistry communications 2024-08, Vol.165, p.107755, Article 107755
• Main Authors: Chai, Hua, Yan, Chengyu, Guo, Jiarong, Lei, Fengrui, Miao, Peng
• Format: Article
• Language: English
• Subjects: Calcium ions; Degradation; DNA hydrogel; DNAzyme; Screen-printed electrode
• ISSN: 1388-2481; 1873-1902
• DOI: 10.1016/j.elecom.2024.107755

[Display omitted] •A novel electrochemical method is developed for Ca2+ assay based on DNA hydrogel system.•Ca2+-dependent DNAzyme and the corresponding substrate are designed as the linkers of DNA hydrogel scaffolds.•Electrochemical species can be released upon Ca2+ activated degradation of DNA hydrogel for improved electrochemical response.•The results of the electrochemical method are consistent with those of ICP-MS. Calcium ion is a type of indispensable metal elements in biology, which participates in processes like maintaining the excitability of neuromuscular muscles. However, calcium content should be monitored in a safety range. Herein, a novel electrochemical method is developed for Ca2+ assay by monitoring electrochemical response after DNAzyme catalyzed DNA hydrogel degradation. Pure DNA hydrogel is first built with three-way junction scaffolds and linkers containing Ca2+-dependent DNAzyme sequence. In the presence of target Ca2+, the substrates in linkers are cleaved and DNA hydrogel can be degraded gradually. The encapsulated electrochemical species thus facilely interact with the electrode, leading to the increase of electrochemical responses. This electrochemical method for Ca2+ quantification is selective and sensitive, which also performs satisfactorily challenging biological samples like sweat and urine.