Automatic photometric titration procedure based on multicommutation and flow-batch approaches employing a photometer based on twin LEDs

Journal of the Brazilian Chemical Society

Silva, Milton B. da¹  Crispino, Carla C.¹  Universidade Federal de São Carlos, São Carlos, Brazil¹  Universidade de São Paulo, Piracicaba, Brazil¹  Reis, Boaventura F.¹ 

关键词: multicommuted flow injection analysis;    flow-bath analysis;    automated photometric titration;    fruit juice;    LED photometer;   

DOI  :  10.1590/S0103-50532010001000009

学科分类：化学（综合）

来源: SciELO

【 摘 要 】

In this work, a reliable and inexpensive photometer based on twin LEDs assembled as a radiation source and as a photodetector is described. The setup including the photometer and flow system module was designed to implement an automated titration procedure employing the multicommuted flow injection analysis (MCFIA) process. The proposed system was able to carry out photometric titration without using analytical curve to achieve the sample concentration. Its usefulness was proven by analyzing vinegar and lemon, orange, pineapple, maracock, and acajou juices. Accuracy was accessed comparing results with those obtained employing a manual procedure and no significant difference was observed at 95% confidence level. Samples presenting different acid concentrations such as lemon juice (1084.73 mmol L-1) and pineapple juice (14.42 mmol L-1) could be titrated using the same titration solution without any modification of the titrating setup.

【 授权许可】

Unknown