Ferron dosage ([Ferron]) is key to ferron-timed spectrophotometry (ferron assay). In order to clarify some important questions, the following studies were conducted: (1) The effect of [Ferron] on the sensitivity of total aluminum (Al<sub>T</sub>) determination was experimentally investigated and <sup>27</sup>Al nuclear magnetic resonance (<sup>27</sup>Al NMR) spectroscopy was used to verify our developed Ferron assay; (2) the chemical equilibrium calculation was employed to analyze the effect of [Ferron] on the determination of Al<sub>T</sub>; and (3) the main reason for insufficient [Ferron] was further analyzed. This is the first study to standardize a ferron assay operating procedure.
Jing Zhang, Fang Chang, Yijin Ren, and Qiuyi Shi, "An Important Improvement in Ferron-Timed Spectrophotometry," Appl. Spectrosc. 67, 985-992 (2013)