J. X. Feng, X. Q. Wang, L. P. Wang and Y. C. Zhang, “Determination of Tramadol Hydrochloride with Two Point Potentiometric Titration,” Chinese Journal of Ana-lytical Chemistry, Vol. 29, No. 12, 2001, pp. 1487-1487.

has been cited by the following article:

• TITLE: Flow Injection Determination of Tramadol Based on Its Sensitizing Effect on the Chemiluminescent Reaction of Permanganate-Sulfite

  AUTHORS: Xun Yao, Jingkai Zhang, Jianguo Li

  KEYWORDS: Chemiluminescence, Tramadol hydrochloride, KMnO4, Sodium Sulfite, Flow-Injection Analysis

  JOURNAL NAME: American Journal of Analytical Chemistry, Vol.2 No.7, October 31, 2011

  ABSTRACT: In this paper, a novel chemiluminescence (CL) method for the determination of tramadol has been developed by combining the flow injection technique and its sensitizing effect on the weak CL reaction between sulfite and acidic KMnO4. A mechanism for the CL reaction has been proposed on the basis of fluorescent and CL spectra. Under the optimized conditions, the proposed method allows the measurement of tramadol hydrochloride over the range of 0.04 - 4 ?g/mLwith a correlation coefficient of 0.9995 (n = 8) and a detection limit of 0.01 ?g/mL (3σ), and the relative standard deviation for 2.0 ?g/mL tramadol (n = 11) is 2.1%. The utility of this method was demonstrated by determining tramadol hydrochloride in tablets and injections.