Phansi Piyawan, Janthama Sirinthip, Cerdà Víctor, Nacapricha Duangjai
Department of Chemistry, Faculty of Science and Technology, Thepsatri Rajabhat University, Lopburi, 15000, Thailand.
Sciware System, 07193, Bunyola, Spain.
Anal Sci. 2022 Oct;38(10):1323-1332. doi: 10.1007/s44211-022-00162-y. Epub 2022 Jul 25.
A simple one-step drawing for the cost-effective fabrication of microfluidic paper-based analytical devices (µPADs) for the determination of phosphate content in water and fertilizer samples is presented in this paper. The hydrophobic barrier of µPAD was patterned using a 2-mm tip marker pen using a transparent acrylic sheet template. The molybdenum blue reaction using ascorbic acid as a reducing agent was used. A pre-concentration step of samples is proposed to improve the sensitivity of the measurement. The blue complex produced on the µPADs was recorded using a smartphone camera. The color intensities (red, green, blue and gray) were analyzed using ImageJ program. The proposed µPAD method provides a linear calibration range from 0 to 100 mg L P. The limit of detection (LOD) was found to be 0.7 mg L P with a precision of 3.1%RSD for 50 mg L P (n = 10). The proposed method was successfully applied to the determination of phosphorus contents in water and liquid chemical fertilizer samples. The results obtained from µPAD agreed with a spectrophotometric method using paired t test at a 95% confidence level.
本文介绍了一种用于制备微流控纸基分析装置（µPADs）的简单一步绘制法，该装置用于测定水和肥料样品中的磷酸盐含量。µPAD的疏水屏障使用2毫米笔尖的记号笔，通过透明丙烯酸片模板进行图案化。采用以抗坏血酸为还原剂的钼蓝反应。建议对样品进行预浓缩步骤以提高测量灵敏度。使用智能手机相机记录µPAD上产生的蓝色络合物。使用ImageJ程序分析颜色强度（红色、绿色、蓝色和灰色）。所提出的µPAD方法提供了0至100 mg/L P的线性校准范围。检测限（LOD）为0.7 mg/L P，对于50 mg/L P的精密度为3.1%RSD（n = 10）。该方法成功应用于水和液体化肥样品中磷含量的测定。通过配对t检验，在95%置信水平下，µPAD获得的结果与分光光度法一致。
