A G-quadruplex-based method to detect ClO in the rostral ventrolateral medulla of stress-induced hypertension by self-complementary DNA probe.

A G-quadruplex-based fluorescent biosensor is introduced that employs a self-complementary DNA probe for detection of hypochlorite ions (ClO) in the rostral ventrolateral medulla (RVLM) of rats afflicted with stress-induced hypertension (SIH). The biosensor capitalizes on the interaction between Thioflavin T (ThT) and guanine-rich DNA sequences, exhibiting exceptional sensitivity, specificity, and swift detection capabilities for ClO. Through optimization of the detection parameters, we achieved a minimal detection threshold of 0.0486 μM and a rapid reaction time of 5 min. The biosensor's high selectivity for ClO was confirmed by its lack of response to other reactive oxygen species (ROS). When applied to SIH rat models, the biosensor revealed markedly elevated ClO levels in the RVLM of SIH rats versus control rats, implicating ClO in the disease's pathophysiology. This label-free, G-quadruplex-based biosensor represents a significant advancement in the detection of ClO⁻, offering a highly sensitive and specific tool for monitoring reactive oxygen species in biological systems. This study not only deepens our comprehension of SIH but also offers a potent diagnostic and monitoring tool for ROS-related diseases, with implications for therapeutic intervention and disease management.