Development of a Micro-Spectrophotometer and Its Application in Water Quality Testing

Abstract

Traditional spectrophotometers have a large volume and slow scanning speed, which limits their applicability for rapid on-site detection. Herein, a micro-spectrophotometer(named ATOM) is fabricated, and its performance is verified in water quality testing. An M-type Czerny-Turner light path structure, a broadband light emitting diode(LED) light source, and a linear charge-coupled device(CCD) photodetector were adopted in ATOM. The performance of ATOM was validated through iron content determination by using o-phenanthroline spectrophotometry. The experiment results showed that the linear correlation coefficient of determination R² was 0.9997 for mass concentrations ranging from 0 to 2.0 μg/mL. The relative standard deviation was 0.37%, and the relative error compared to a commercial large-scale spectrophotometer was below 1.4%. The dimensions of ATOM are 75 mm × 60 mm × 25 mm, with hardware costs of approximately 1 000 CNY. ATOM features compact size, low cost, rapid measurement, high integration and high precision, making it suitable for portable on-site rapid detection.

Keywords

micro-spectrophotometer / water quality testing / portability / low cost / linear CCD

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Funding

National Natural Science Foundation of China(62375048)

Natural Science Foundation of Shanghai, China(22ZR1402600)