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A highly simple, rapid and sensitive spectrophotometric procedure is described for micro-amounts determination of titanium (IV) using tannic acid (tannin) as a new reagent in presence of Triton X-100 (micellar medium). Titanium (IV) reacted with tannic acid in slightly acidic medium at pH=6 using citrate buffer solution to form a 1:2 red coloured stable complex with maximum absorption at 436 nm. The complex is instantaneously formed and remain stable over 2 hr. Beer's law is obeyed in the range of 2-26 µg Ti ml-1 with molar absorptivity to be 3.66 × 10 4 L mol-1 cm-1. The proposed method is successfully applied for titanium determination in steel, paint and pharmaceutical samples.

A rapid and accurate reversed phase-UHPLC method is developed for determination of gallic acid, quercetin and kaempferol in herbal drugs found in herbal product purchased from local market. A reversed phase chromatographic analysis is carried out under isocratic conditions using column Phenomenex, Prodigy, ODS3, 5.0 μm, 100 A, 250 × 4.6 mm (USA). The mobile phase is methanol and 0.5 % phosphoric acid (50:50 v/v). The flow rate is 1.3 mL min-1. The injection volume is 20 µL. The detection wavelength (λ max) is 370 nm using a PDA (photodiode array detector). Linearity of the method is established over the concentration ranges of 240-960 µg mL-1 for quercetin with a retention time about 7.8 minutes. Correlation coefficient is greater than 0.99. The recovery level of quercetin is 99.94 %. The described method is quite suitable for routine analysis of herbal drugs by reversed phase-UHPLC Method. The proposed method is used for routine analysis to estimate the selected polyphenols under study in its pure form as well as in some herbal drugs forms.

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