Research on Key Technologies of Dual-Light-Type Photoelectric Colorimetric Method for Phosphate Determination

Phosphate plays a crucial role in microbial proliferation, and the regulation of the phosphate concentration can modulate the fermentation efficiency. In this study, based on Lambert-Beer's Law and the selective absorption characteristics of substances under light, a dual-light-type photoelectric colorimetric device for phosphate determination was designed. The device's main components, such as the excitation light path and incubation stations, were modeled and simulated. The primary performance of the instrument was verified, and comparative experiments with a UV-1780 spectrophotometer were conducted to validate its performance. The experimental results demonstrate that this device exhibits a high degree of linearity with an R² value of 0.9956 and a repeatability of ≤1.72%. The average temperature rise rate at the incubation stations was measured at 0.44 °C/s, with a temperature uniformity ≤ ±0.1 °C (temperature set at 37.3 °C). Consistently observed trends in the measurement of 23 CHO cell suspensions using the UV-1780 spectrophotometer further validated the accuracy and reliability of the device's detection results.