In this letter, a temperature compensated differential (TCD) photoacoustic (PA) method is proposed to simultaneously suppress the side-effect of multiple interferences, significantly improving the accuracy and sensitivity of liquid PA detection. We firstly established a theoretical model to prove the validity of this method. Then a differential PA detection system was set up to detect glucose concentration, a typical weak absorbing substance in the near-infrared range. The experimental results demonstrate that a trace-level detection limit of () for glucose solution was obtained. The TCD-PA method provides a feasible way for on-line high-precision detection of liquid substances.

在这封信中，提出了一种温度补偿差分 (TCD) 光声 (PA) 方法来同时抑制多种干扰的副作用，显着提高液体 PA 检测的准确性和灵敏度。我们首先建立了一个理论模型来证明该方法的有效性。然后建立差分PA检测系统来检测葡萄糖浓度，这是一种典型的近红外范围弱吸收物质。实验结果表明，获得了（）对葡萄糖溶液的痕量检测限。TCD-PA方法为液体物质的在线高精度检测提供了一种可行的方法。