title: Development and validation of a sensitive and fast solid-phase spectrophotometric procedure for phenol determination in pharmaceuticals.
abstract: A very sensitive, simple, and fast solid-phase spectrophotometric procedure for the determination of phenol using the p-nitrobenzenediazonium reagent (DAR reagent) was developed. This procedure is based on the simultaneous concentration of the orange product on a Dowex 1-X2 anion exchanger within 15 min, and a direct absorbance measurement of the sorbed species at both 530 nm (the absorption maximum of the phenol-DAR in the resin phase) and 700 nm (the range where only the resin absorbs light). Quality control and evaluation of the analytical parameters was carried out using a comprehensive prevalidation strategy. The linearity of the method was confirmed within an analyte working range from 0.01 to 0.10 µmol (0.2 to 2.0 nmol mL(-1)). The precision ranged from ±1.17 to ±9.61%; the accuracy ranged from -17.50 to +17.81%. The evaluated limiting values were L(D) = 0.0013 µmol and L(Q) = 0.0082 µmol. The DAR-SPS method was successfully applied to the determination of phenol in a pharmaceutical sample of salicylic acid (98.0-100.0%) and vaccines (98.0-103.4%).
authors.affiliation: Department of Analytics and Control of Medicines, Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia. jadranka@pharma.hr
authors.forename: Jadranka
authors.initials: J
authors.lastname: Vuković
authors.forename: Shiro
authors.initials: S
authors.lastname: Matsuoka
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Yoshimura
authors.forename: Renata
authors.initials: R
authors.lastname: Jurišić Grubešić
authors.forename: Dario
authors.initials: D
authors.lastname: Kremer
authors.forename: Nataša
authors.initials: N
authors.lastname: Šantić
mesh_terms: D002626:Chemistry, Pharmaceutical / Q000379:methods*; D004340:Drug Contamination; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents / Q000737:chemistry; D007474:Ion Exchange; D009578:Nitrobenzenes / Q000737:chemistry; D004364:Pharmaceutical Preparations; D019800:Phenol / Q000032:analysis; D015203:Reproducibility of Results; D020156:Salicylic Acid / Q000032:analysis*; D012680:Sensitivity and Specificity; D014612:Vaccines / Q000032:analysis*
chemical_list: D007202:Indicators and Reagents; D009578:Nitrobenzenes; D004364:Pharmaceutical Preparations; D014612:Vaccines; D019800:Phenol; C036077:nitrobenzene; D020156:Salicylic Acid