de Jesus Diogo M, Delaqua Felippe, da Silveira Petruci João Flávio, Silva Sidnei G
Institute of Chemistry, Federal University of Uberlândia, 2121 João Naves de Ávila Avenue, Santa Mônica, Uberlândia MG38400-902, Brazil.
Electrical Enginering Department, Federal University of Uberlândia, 2121 João Naves de Ávila Avenue, Santa Mônica, Uberlândia MG38400-902, Brazil.
ACS Omega. 2025 May 20;10(21):21867-21874. doi: 10.1021/acsomega.5c01857. eCollection 2025 Jun 3.
Portable photometers fabricated with low-cost optical components have been developed for a wide range of analytical applications. However, their analytical performance is closely related to the spectral range of the colored solution, as it depends on the detector material used in commercially available digital light sensors. A modular DIY, plug-and-play photometer was designed for quantitative absorbance measurements. Four digital light sensors (BH1750, TSL2591, LTR329, and LTR303) were evaluated for detecting colored solutions. LTR329 and LTR303 were found to provide optimal performance due to their broad spectral coverage, enhancing the device's analytical capabilities. The photometer integrates an LED light source (635 nm) and a microcontroller (Adafruit ESP32-S3), enabling easy operation and data processing. It was employed to determine sulfide concentrations in wastewater using the methylene blue method and urea levels in Automotive SCR fluid samples with the Schiff reaction. The analytical results for sulfide (0.26-3.00 mg L) and urea (0.20-3.00% w/v) were comparable to those obtained by official methods, with detection limits of 0.09 mg L for sulfide and 0.06% (w/v) for urea. The device's modularity ensures easy component replacement, ensuring longevity and adaptability. With portability, 18-h battery life, and reliability, it is ideal for on-site analyses in remote settings. This study, not previously reported in the literature, presents the photometer as a valuable, sustainable tool for analytical measurements in resource-limited environments.
采用低成本光学元件制造的便携式光度计已被开发用于广泛的分析应用。然而，它们的分析性能与有色溶液的光谱范围密切相关，因为这取决于市售数字光传感器中使用的探测器材料。设计了一种模块化的DIY即插即用光度计，用于定量吸光度测量。对四个数字光传感器（BH1750、TSL2591、LTR329和LTR303）进行了检测有色溶液的评估。发现LTR329和LTR303由于其广泛的光谱覆盖范围而提供了最佳性能，增强了该设备的分析能力。该光度计集成了一个LED光源（635 nm）和一个微控制器（Adafruit ESP32-S3），实现了易于操作和数据处理。它被用于采用亚甲基蓝法测定废水中的硫化物浓度，以及采用席夫反应测定汽车SCR流体样品中的尿素含量。硫化物（0.26 - 3.00 mg/L）和尿素（0.20 - 3.00% w/v）的分析结果与官方方法获得的结果相当，硫化物的检测限为0.09 mg/L，尿素的检测限为0.06%（w/v）。该设备的模块化确保了部件易于更换，保证了使用寿命和适应性。凭借便携性、18小时的电池续航时间和可靠性，它非常适合在偏远地区进行现场分析。本研究在文献中未曾报道过，它将该光度计作为一种在资源有限环境中进行分析测量的有价值的可持续工具进行了介绍。
