Untitled

Abstract

A validated spectrophotometric method has been described for the assay of nifedipine in bulk and commercial dosage forms. The method is based on the oxidation of drug with Fe(III) at pH 1.42. The reduced Fe(II) subsequently reacts with 1,10-phenanthroline to produce a red colored tris(1,10-phenanthroline) iron(II) complex, which absorbs maximally at 505 nm. Beer's law is obeyed in the concentration range 0.5 -14.0 µg mL -1 with molar absorptivity and Sandell' s sensitivity of 2.805×10 4 L mol -1 cm -1 and 0.012 µg cm -2 per 0.001 absorbance unit, respectively. The various experimental parameters were optimized. The method has been successfully applied for the quantitation of the drug in commercial dosage forms. The results of analysis were statistically compared with those of a reference method showing acceptable recovery and precision. The experimental true bias of all samples based on recovery experiments were within ± 2 %.

A Kinetic spectrophotometric method for determination of amlodipine and Nifedipine in pharmaceutical preparations

“…The proposed kinetic method was fast and resulted in dynamic ranges and detection limits better or comparable with the existing spectrophotometric methods based on oxidation of drugs [22][23][37][38]. The method was applied to the analysis of pharmaceutical preparations containing AML or NIF, successfully.…”

“…The calculated detection limits for AML and NIF were 0.10 and 0.19 Pg ml -1 , respectively. In Table 3 are compared the linear range, detection limit and procedure time of the previously reported methods using different oxidizing agents [22][23][37][38] with those of the proposed methods for AML and NIF. As it is seen, the proposed method for AML not only represented wider in comparison with the other existing methods.…”

“…In the case of NIF, although the proposed method does not represent significant improvement for dynamic range and detection limit, it can be preferred with respect to lower measuring time or better experimental conditions. For example, the method used Fe(III)-1,10-phenanthroline as reagent [38], needs 5 min heating at 100 ºC and that used potassium hydroxide [37] was performed in dimethyl solfuxide which is not preferred for its environmental hazards.…”

“…Similarly, survey of literature for NIF revealed methods based on GC [24][25][26], different liquid chromatographic methods [27][28][29][30][31][32], and stripping voltammetry [33,34]. There are also some equilibrium visible spectrophotometric methods for NIF that are based on oxidation or reduction of the drug, where reactions products are colored [35][36][37][38]. Surprisingly, according to the best of our knowledge, no kinetic spectrophotometric method has been reported for the quantitation of the DHP derivatives.…”

School Procurement Information System (SIPLah) as Moderating of Determinant of Fraud in Goods/Services Procurement

“…In contrast to some of the research results above, research by Romaissah et al (2019) shows that the implementation of the E-procurement system has no significant effect on preventing fraud in the procurement of government goods/services, while simultaneously eprocurement and internal control have a significant effect on preventing fraud in the procurement of government goods/services. Research by Azmi & Rahman (2015) shows the results of e-procurement can dispute political and economic forces in the government purchasing process; manage demand and interference when awarding government contracts; and be used efficiently in government and business relations. Azmi & Rahman (2015) also concluded that e-procurement is only a tool to moderate public procurement fraud, not a solution to the fraud problem.…”