Quantitative determination of Na-luminolate by chemiluminescence method in pharmaceutical preparations

Abstract

A procedure for the chemiluminescence determination of Na-luminolate (NaHL) was developed. It is based on the oxidation of luminol with diperoxysuccinic acid (DPSA) in an alkaline solution (pH 10.3). At concentrations of DPSA 5.8 × 10^–4 mol/L and NaHL in the range from 1.5 × 10^–7 to 1.02 × 10^–6 mol/L at pH 10.3 (in phosphate buffer solution), I_max is proportional to c(NaHL): I_max = (2.76 ± 0.30) × 10⁷c + (0.34 ± 1.78) (r = 0.998). LOD = 6.10 × 10^–8 mol/L; LOQ = 2.03 × 10^–7 mol/L. The procedures were developed, and the possibility of quantitative determination of NaHL in sublingual tablets "Galavit" 25 mg and powder for preparing a solution for injection "Galavit" 100 mg using the method of chemiluminescence by reaction with DPSA was shown. RSD ≤ 2.2%, (δ = (x̅-μ) × 100%/μ =  + 1.16%….. – 0.41%, respectively). The results of the determination of NaHL in tablets and powder for preparing a solution for injection of "Galavit" 100 mg by the proposed method agree with those obtained by the standard pharmacopeia method. The reliability of the obtained measurement results is proved by comparing the accepted reference value (μ) with the level of results of the proposed method: |(x̅-μ) × 100%/μ|< t_α(0.95, n = 5) × RSD/√n.