No abstract

A modern development discusses the synthesis and validity of simple, sensitive, and versatile spectrophotometric methods for Bi(III) and Al(III) determination in pharmaceutical formulations have been conducted. In the present paper, 4-(4 acetamidophenylazo) pyrogallol has been synthesized as a new organic compound, 4-APAP, by coupling pyrogallol in a regulated pH medium with diazotized p-aminoacetanilide. 4-APAP was identified by methods of FT-IR, 1H-NMR, 13C-NMR, and thermal analysis (thermogravimetry and differential scanning calorimetry). Solvatochromic activity was also studied in solvents with different polarities. The Kamlet and Taft linear solvation energy relationship was used to correlate shifts in UV-Visible spectra of 4-APAP with Kamlet-Taft parameters (α, β, and π*). The optimum assay conditions showed linearity from 0.3–13 to 0.5–11 μg·mL−1 for Bi(III) and Al(III), respectively. Molar absorptivity values were 3.365 × 104 and 0.356 × 104 L·mol−1·cm−1 for Bi(III) and Al(III), with similar Sandell's sensitivity measures of 0.006 and 0.008 μg·cm−2. Detection limits and quantification limits were 0.013 and 0.043 μg·mL−1 for Bi(III), respectively, and 0.018 and 0.059 μg·mL−1 for Al(III) with the relative standard deviation for determination of both metal ions using 4-APAP probe being <2.0%. The validity, accuracy, and efficiency of the approaches were demonstrated by the determination of Bi(III) and Al(III) in different formulations.

Background: A new approach describing the validation and development of an easy, new spectrophotometric and kinetic method for identification of para-aminobenzoic acid in dietary supplement has been performed. In this study, para-aminobenzoic acid was derived in a pH-controlled environment, as a new organic compound 4(4-Benzophenylazo)pyrogallol, by incorporating diazotized para-aminobenzoic acid with pyrogallol. Objective: The determination of para-aminobenzoic acid was conducted by the fixed time and initial rate techniques. These approaches were based on the reaction of the compound containing paraaminobenzoic acid, 4(4-Benzophenylazo)pyrogallol, with Ag(I) to form colored product with a maximum absorbance at 468nm. Both of these techniques were adopted for constructing the calibration curves and examined for their suitability for the quantitation of para-aminobenzoic acid in dietary supplement. Methods: The determination process was established, using initial rate and fixed time kinetic spectrophotometric methods. Results: 4(4-Benzophenylazo)pyrogallol was characterized using proton-nuclear magnetic resonance, Fourier-transform infrared, differential scanning calorimetry and thermogravimetric thermal methods, gas chromatography–mass techniques, and solvatochromic behavior in solvents with different polarities was also examined. Conclusion: For the first time, para-aminobenzoic acid was well determined by incorporating it as an organic solid compound, 4(4-Benzophenylazo)pyrogallol, through coupling pyrogallol with diazotized para-aminobenzoic acid in regulated pH medium, ranging between 5.0 to 6.0. The existence of common excipients in the dietary supplement did not produce any significant interference. F- and ttest data analysis were used for statistical comparison of the suggested techniques with that of reference method, demonstrating excellent agreement with no significant difference in the associated precision and accuracy.