A Green Chemosensing Approach for Direct and Liquid-liquid Extractive Spectrophotometric Determination of Platinum

In this study, a highly selective colorimetric chemosensing behavior of 4-(2'-furalideneimino)-3-methyl-5-mercapto-1,2,4-triazole (FIMMT) was used for the determination of platinum ions. The developed method is simple, cheap, and rapid. It obeys the principle of green chemistry since n-butanol used as an extraction solvent for platinum determination in aqueous solutions was further recycled and did not release toxic wastes. Platinum forms a red-colored soluble complex with FIMMT at pH 5.4 on heating. Platinum(II)-FIMMT complex was instantly extracted into n-butanol. The complex absorbance in aqueous and n-butanol solutions was found at lambda(max) of 510 nm. The complex was stable for more than 24 h in the presence of other ions with the extinction coefficient of 11686 L/mol . cm and Sandell's sensitivity of 0.017 mu g/cm(2). The effect of pH, excess of reagent, and foreign ions on the determination of platinum as well as the influence of heating time, stability, and solubility of the complex in various solvents were studied. The system obeyed Beer's law up to 17.5 mu g/mL, and the optimum range was evaluated by Ringbom method. The developed method showed excellent linearity and a correlation coefficient of 0.999. The method is precise, and it was applied for platinum determination in synthetic matrices, real samples such as cis-platin injection and platinum-rhodium thermocouple wire. The chromogenic reagent FIMMT selectively reacts with nickel, palladium, and platinum, which helps to separate them quantitatively.

Automated summary

In this study, a simple, cheap, and rapid method was developed for the determination of platinum ions. The method follows the principle of green chemistry by recycling the extraction solvent and not releasing toxic wastes. The developed method showed excellent selectivity and stability, and it was successfully applied to synthetic matrices and real samples.