Three new methods using titrimetric and spectrophotometry are described for the determination of Propranolol Hydrochloride (PPH) and Atenolol (AN) with potassium bromate as the oxidimetric reagent and acid dyes, Methyl orange and Indigo carmine. In direct titrimetric (method A), the drug is titrated directly with bromate in acid medium and in the presence of excess of bromide using methyl orange indicator. Both spectrophotometric methods are based on the oxidation of mentioned drugs by a known excess of bromate in acid medium and in the presence of excess of bromide followed by estimation of surplus oxidant by reacting with either Indigo carmine (method B) or Methyl orange (method C), and measuring the absorbance at 609 or 507 nm. Titrimetric methods are applicable over the ranges 1-18 mg for propranolol hydrochloride and 2-10 mg for atenolol. In spectrophotometric methods, the absorbance is found to increase linearly with increasing concentration of drugs, which is corroborated by calculated correlation coefficient (r) of 0.9933, 0.9977, 0.9928 (B) and 0.9951, 0.9976, 0.9984 (C). The systems obey Beer’s law for 2.5-15, 0.625-7.5mg mL-1 (B) and 0.25-5, 0.25-2mg mL-1 (C) for atenolol and propranolol hydrochloride. The proposed methods were applied successfully to the determination of mentioned drugs in tablets. The accuracy of the methods was ascertained by recovery studies.

In this study, SBA-15-PAMAM mesoporous nano-adsorbent was synthesized, characterized and applied for adsorption of acid dyes (acid blue 62 (AB62) and acid red 266 (AR266)) from aqueous Media. Adsorption of AB62 and AR266 on SBA-15 ordered mesoporous silica, polyamidoamine functionalized SBA-15 (SBA-15-PAMAM), has been investigated. To evaluate the synthesized adsorbent constructional, FT-IR (Fourier transform infrared spectroscopy), TEM transmission electron microscopy images and XRD (X-ray diffraction) methods were utilized. To investigate and compare the adsorption of two acid dyes with each other, the chemical structure and molecular mass of two acid dyes on the synthesized nano-adsorbent is compared with each other. The acid blue 62 dye with the structure of Anthrachinon (MW=422.43) and the acid red 266 dye with the structure of Azo (MW=467.78) is compared with each other. To appraise the proficiency of this nano-adsorbent for adsrption of two acidic dyes from aqueous media, the efficacy of significant parameters comprising pH (2-10), adsorbent dosage (0.01-0.1 g), dye concentration (200-600 mg g-1), contact time (10-120 min) and temperature (25-45 oC) was investigated. The Langmuir, Freundlich, Tempkin and Dubin Radushkevich isotherms were perused. The empirical data were best demonstrated by the langmuir isotherm model with utmost adsorption valence of (1428.57 mg g-1) for dye AB62, and (1111.11 mg g-1) for dye AR266 at pH 2 and 25 °C, in absolute agreement with the empirical data (R2>0.9933) for dye AB62 and (R2>0.9914) for dye AR266. It was concluded that SBA-15-PAMAM adsorbent could be applied as a significant adsorbent for acidic dyes removal.