Fig. 2. The influence of intramolecular hydrogen bond on HNO-releasing t1/2.
(A) NO absorption by IL [Ch][Tau] at 30°C. (B) Spectrochemical monitoring of [Ch][Tau]-NONOate decomposition (red) was collected at 330 nm every 15 min (1-hour intervals shown) in PBS (pH 7.4) at 37°C. Spectrochemical of [Ch][Tau] in PBS (pH 7.4) at 37°C (black) has no absorption peak at 330 nm. Inset: Representative decay rates of [Ch][Tau]-NONOate. (C) Release kinetics of HNO and NO for [Ch][Tau]-NONOate in pH 7.4 PBS and at 37°C. (D) Energy gap between two different structures of [Tau]-NONO. (E) Optimized structures of [Tau]-NONO, [AMS]-NONO, [APS]-NONO, and [APA]-NONO. (F) Relationship between the lengths of intramolecular hydrogen bond and the t1/2.