A diaminotriazine-functionalized polydiacetylene for colorimetric sensing of thymine and oligothymidine

The development of analytical methods for qualitative and quantitative detection of DNA and its core bases has attracted great attention. In this study, a diaminotriazine (DAT)-containing polydiacetylene (PDA-DAT) colorimetric sensor was developed for selective detection of thymine and oligothymidine. PDA-DAT displayed a blueto-purple color change in the presence of thymine with a detection limit of 12.6 nM. FTIR analysis demonstrated that the color change is associated with formation of multiple hydrogen bonds between the DAT and thymine moieties in a molecular recognition process. As a consequence of the hydrogen bonding interactions, a change in the conformation of the PDA conjugated backbone takes place, causing an absorption spectral shift and corresponding color change. The PDA-DAT sensor system also selectively detects oligothymidine (40 mer) with a detection limit of 14.6 nM. The results of this study should serve as a foundation for the design of colorimetric sensors for thymine and oligothymidine.

Automated summary

A diaminotriazine (DAT)-containing polydiacetylene (PDA-DAT) colorimetric sensor was developed for selective detection of thymine and oligothymidine. PDA-DAT undergoes a color change in the presence of thymine and oligothymidine due to hydrogen bonding interactions, resulting in absorption spectral shift and corresponding color change. The detection limits for thymine and oligothymidine are 12.6 nM and 14.6 nM, respectively. This study provides a foundation for the design of colorimetric sensors for thymine and oligothymidine.