ANALISIS TIMBAL, KOLORIMETRI, FERRO FUMARAT, KOMPLEKS PB-DITIZONATDEVELOPMENT OF ANALYTICAL METHOD FOR COLORIMETRIC DETERMINATION OF LEAD (PB) IN FERRO FUMARATE AS ACTIVE PHARMACEUTICAL INGREDIENT (API) BY MEANS OF PB-DITIZONAT COMPLEX FORMATION

• Main Author: Purwaniati
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/49417
• Institution: Institut Teknologi Bandung

Ferro Fumarate (FF) as active pharmaceutical ingredient (API) may contains not more than 10 or 20 ppm lead (Pb) according to FI and USP or BP, respectively. The compendial method for determination of Pb is based on Inductively Coupled Plasma (ICP) or Atomic Absorption Spectroscopy (AAS) method. Despite modern instrumental method, the determination of Pb is strongly interfered with iron (Fe). The purpose of this research was to obtain a colorimetric method for determination of Pb in FF as alternative to compendial method. After precipitation of ferrous ions with NaOH, Pb was reacted with dithizone (1,5-diphenylthiocarbazone) in aqueous ethanol solution (80:20) to form a complex measureable in visible region. In addition, cyanide and hydroxylamine were respectively added as masking agent and stabilizer. Complex formation was observed in pH range of 1 to 8 in which optimum complex was formed at pH 6,8 showing wave length with maximum absorbance at 500 nm. Calibration curve in the range of 0,5 to 3 ppm shows good linearity with an equation of Y = 0,168x + 0,017 and a correlation coefficient of 0.999. Absorbance of Pbdithizonate complex measured at 500 nm was stable up to 30 minutes. The complex formation under influence of interfering metal cations including Cu 2+ , Zn 2+ , Cd 2+ , Fe 2+ , Fe 3+ , Co 2+ and Mn 2+ was also observed. The precision of the aeration method, calculated as within- and inter-day relative standard deviation (RSD) were 13,67 and 13,46%, while its accuracy, calculated as % of recovery at concentration level of 20 and 40 ?g were 97,76 dan 108,21%, respectively. While accuracy and precison of the ion Ce 4+ oxidation with RSD 8,15; 3,79 dan 0,96 and %recovery 104,96; 83,07 and 112,78%, for spike level 5, 20 and 40 ?g, respectively. Limit of detection (LOD) and limit of quantification (LOQ) based on statistical method were 0.11 and 0.38 ppm, respectively. Based on overall results, it was concluded that the developed method can be applied alternative method for determination of Pb in FF.