双亲性噻吩羧酸衍生物的制备及潜指纹检测应用

Amphiphilic carboxylic acid derivatives, 5-[4-(diphenylamino)phenyl]-thiophen-2-carboxylic acid (TTC-H) and its potassium salt (TTC-K), were synthesized from Suzuki coupling reaction of 5-bromothiophen-2-carboxylic acid and 4-(diphenylamino)benzeneboronic acid, and characterized by ¹HNMR and ¹³CNMR. The TTC-H and TTC-K were further evaluated by UV-Vis absorption spectroscopy and fluorescence emission spectroscopy for analyses on their photophysical properties as well as aggregated states, with density-functional theory calculations and solvation colorimetric effects carried out and their crystal structures analyzed by Hirshfeld surface analysis. TTC-K aqueous solution was then applied to latent fingerprint imaging by chemical impregnation and atomization methods. The results showed that there were weak interaction forces between TTC-H molecules, such as C···H (31.6%, accounting for the percentage of the total interaction force, the same below), H···H (44.6%) and O···H (14.6%). Both TTC-H and TTC-K possessed the property of aggregation-induced emission. TTC-K aqueous solution was then applied to latent fingerprint imaging by chemical impregnation and atomization methods. Both methods could accurately and efficiently obtain the tertiary structure of latent fingerprints. And even at low concentration (5×10^–5 mol/L), the TTC-K aqueous solution reagent was able to rapidly identify latent fingerprints (≤5 s) by chemical impregnation method with good aging stability, while the atomization method is easier to be implemented, while exhibited good imaging capacity for both old fingerprints (≤14 d) and fingerprints soaked in water (≤7 d).