Bright green emission non-conjugated polymer dots: pH trigged hydrogel for specific adsorption of anionic dyes and visual detection of tert-butylhydroquinone

In recent years, non-conjugated polymer dots (PDs) have attracted considerable interests due to their fundamental importance and potential applications in diverse areas. Herein, we synthesized the green emissive non-conjugated PT PDs with polyethyleneimine (PEI) and tetrakis(hydroxymethyl)phosphonium chloride (THPC) as precursors in one-pot at room temperature with the quantum yield at 25%. Surprisingly, PT PDs solutions could be transformed to hydrogels by pH alteration. By characterization, PT PDs hydrogels performed porous structure with large surface area and positively charged functional groups. Anionic dyes could be easily adsorbed into PT PDs hydrogels through multiple electrostatic interactions. In addition, PT PDs could specifically detect tert -butylhydroquinone (TBHQ) with a low detection limit (27 µM), suggesting their high sensitivity. More importantly, the developed method was successfully applied the detection of TBHQ in the peanut oil, implicating their practical application.