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An innovative and comprehensive range of chromogenic reagents or colorimetric reagents are generally used for the application in the field of spectroscopic quantitative and qualitative analysis. There are number of reagents which are mostly utilized for the estimation of pharmaceutical medicinal agents. Functional groups generally present in medici...
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... In recent times, there has been a significant focus on oxidation reactions as a viable method for the analysis of pharmaceutical compounds [21]. Colorimetric reagents are commonly employed in the realm of spectroscopic quanti-VOLUME 22, ISSUE 2, Pages 5-9 FIGURE 1: Chemical structure of Ganciclovir [30] tative and qualitative analysis [22]. One of the colorimetric reagents is N-bromosuccinimide (NBS) [23] that is a bromination reagent with high specificity in both free-radical substitutions and electrophilic additions of unsaturated systems due to its ability to liberate small amounts of bromine [24]. ...
A versatile and simple spectrophotometric technique has been presented for the detection of Ganciclovir (GANCICLOVIR) in pharmaceutical formulations. The oxidation method included mixing an excessive amount of N-bromosuccinimide (NBS) with Ganciclovir in an acidic solution, then calculating the amount of unreacted NBS using methyl blue at \(\lambda\) 610 nm. With a superior molar absorption of \(3.39 \times 10^{-3}\) L mol\(^{-1}\) cm\(^{-1}\), the amount of NBS interacting with the colorant is equal to the amount of the drug. The Sandell's sensitivity index was 0.169 g cm\(^{-2}\), the Beer-Lambert law scale was 1-35 \(\mu\)g mL\(^{-1}\), and the recovery of the concentration was 99% with a relative standard deviation of 0.01%. The technique was successfully used to measure the drug content in pharmaceutical formulations. The precise quantification of Ganciclovir, a highly effective antiviral medication, is of considerable significance in the fields of pharmaceutical analysis and clinical practice. The objective of this study was to establish a dependable and effective approach for the quantification of Ganciclovir via an oxidation reaction employing N-bromosuccinimide (NBS) as the oxidizing agent.
... The diazotization reaction was chosen because it is simpler, more accurate, and cheaper in detecting CAP by producing an intensely colored azo dye solution that produces a maximum absorption at a wavelength at 575 nm [10]. Ravisankar [11] analyzed azo dye at a wavelength at 550 nm. So in this research, the absorbance of azo dye solution was measured at a wavelength at 550-575 nm. ...
... Diazonium cations react with N-(1-naphthyl) ethylenediamine dihydrochloride (NEDA) through electrophilic substitution, with diazonium salts as electrophiles to produce the purple azo dye shown in Figure 5. Purple-colored azo compounds can be identified by spectrophotometry at the maximum absorption wavelength of 565 nm. NEDA is used because it is highly sensitive, can be used in acidic solutions, and is widely used as a reagent for determining samples containing primary amine groups [11], [20]. The mechanism of formation of azo compounds is shown in Figure 6. ...
This research aimed to determine the concentration of chloramphenicol in shrimp using the standard addition method based on the diazotization reaction using Zn powder as a reducing agent of chloramphenicol, followed by the use of N-(1-naphthyl) ethylenediamine dihydrochloride as a coupling agent and measured at 565 nm. Based on the test, the shrimp sample was found to contain 1964.91 mg/kg of chloramphenicol and it exceeded the requirements set by the European Commission which was 0,15 mg/kg. The limit of detection (LOD) value is 0.19 mg/mL and the limit of quantitation (LOQ) value is 0.64 mg/mL. The correlation coefficient (R2) was 0.9991 for the concentration range of 0-50 ppm. The analysis of the results showed that the %recovery in shrimp analysis using this method was 87.41%-107.73% with an average of 109.38%.
Spectrofluorimetry is an analytical technique with high sensitivity, specificity, and simplicity, and is very economical. Drugs that lack native fluorescence are derivatized with reagents so that highly fluorescent compounds are formed that can be readily detected by spectrofluorimetry. There are different reagents such as 4-chloro-7-nitrobenz-2-oxa-1,3-diazole (NBD-Cl), N- methylnicotinamide chloride (NMNCl), 9-flurenylmethylchloroformate (FMOC-Cl), dansylchloride (DNS-Cl), 3-methyl-2-benzothiazolinone hydrazone hydrochloride (MBTH), 1,2-naphthoquinone-4-sulfonate (NQS), 1,4- benzoquinone, 4-fluro-7-nitrobenzofurazan (NBD-F), ninhydrin, benzoin, N- bromo succinimide (NBS), acetylacetone & HCHO, ortho-phthalaldehyde (OPA), and 2-cyanoacetamide used in spectrofluorimetric determination of the drugs that lack native fluorescence. The present review highlights these reagents with principle, reaction conditions, and their applications.
