Spectrophotometric trace determination of Ce(IV) with 6-Chloro-3-hydroxy-7-methyl-2-(2′-thienyl)-4-oxo-4H-benzopyran as an analytical reagent along with DFT and antibacterial activity

Abstract

Spectrophotometric trace determination of Ce(IV) was established with 6-Chloro-3-hydroxy-7-methyl-2-(2′-thienyl)-4-oxo-4H-benzopyran(CHMTB) (0.1%w/v in C₂H₅OH) based on its ability to form a complex of pale yellow color in presence of 0.2 M H₂SO₄ (pH 4.56) with stoichiometry of 2:1 (L:M) between Ce(IV) and CHMTB at λ _max 445 nm. Several physical factors like reagent concentration, acid concentration, time of complex formation and pH were thoroughly examined for trace level detection of cerium(IV). Beer’s law absorbance is linearly related to the Ce(IV) concentration up to 1.8 μg/ml with a correlation coefficient of 1.232. Molar absorptivity coefficient was 8.45 × 10⁴ l/mol/cm, relative standard deviation was 0.2424 %, Sandell’s sensitivity was 0.00165 μg/cm and detection limit was 0.2742 μg/ml. The DFT/B3LYP/6-31G(d,p) method is a commonly used computational approach used for studying molecular properties and to calculate energy gaps for complex and ligand which are found to be 2.0899eV and 3.7652eV respectively in the present study. The above-mentioned complex showed significant antibacterial activity. The present method was easy, selective, sensitive, accurate and showing stability for 48 h.