Utility of potassium iodate for the estimation of lornoxicam, meloxicam and sulbutiamine in pharmaceutical formulations

In this study, a simple and accurate method was described for the determination of lornoxicam, meloxicam and salbutiamine. The method involved the oxidation of drugs with potassium iodate in acidic medium with the liberation of iodine. The liberated iodine was extracted into cyclohexane and the absorbance was measured at 520 nm. The effect of different experimental parameters on the development of the color was studied [the concentration of the reagent, temperature and reaction time]. The method was applicable over a concentration range of 0.10-0.50, 0.05-0.30 and 0.05-0.40 mg ml-1 for lornoxicam, meloxicam and salbutiamine, respectively. The proposed method was successfully applied to the determination of the studied drugs in bulk powder and in the pharmaceutical dosage forms. The validity of the method was assessed by applying the standard addition technique

Spectrophotometric determination of tetracycline by coupling with diazonium salts

A simple, rapid and accurate spectrophotometric method for the determination of tetracycline [TC] in aqueous solution was developed. The method was based on the coupling reaction between TC and diazontized p-nitroaniline [I], sulfanilic acid [II], and sulfanilamide [III] to form stable dyes. The variables affecting development of the color were investigated and the conditions optimized. The Beer's law was obeyed for up to 19, 70 and 40 ppm on using I, II and III, respectively. Their absorptivities [L mol-1 cm-1] and Sandell's sensitivities [mug cm-2] are 125 x 104, 4.0 x 104 and 0.13 x 104 and 38.4 x 10-3, 175 x 10-3 and 148.0 x 10-3, respectively, for I, II and III. The recoveries of the method for I, II and III were 100.07 +/- 0.24, 98.97 +/- 0.64 and 99.95 +/- 0.45 for TC, while the recoveries for the dosage forms were 100.2 +/- 0.277, 100.0075 +/- 0.227 and 99.075 +/- 0.297, respectively. The proposed methods were applied for the quantitation of TC in pharmaceutical preparations with high precision and accuracy. The nature of the dye formation and the structure of mono azo dye was suggested

Compounding and testing of three modified elastomers as parenteral stopper

Tetramethylthiouram disulphide TMTD is known as vulcanizing agent alone or with mercaptobenzothiazole [MBT] in the presence of small quantity of sulfur. Different concentrations of TMTD were added to natural crepe and to bromobutyl rubber mixes in 0.5-3% w/w of rubber at different curing temperatures [140-160C]. It was found that the addition of 2% TMTD for each one of the two elastomers at 150C yielded products with good physicomechanical and swelling properties. When the vulcanizing system of 2% TMTD and 0.1% MBT was used, a delay in the cure time [Tc90] and an increase in the scorch time [TS2] were observed, the effect of blending the natural and bromobutyl rubber mixes in different% showed that increasing the natural rubber [NR] in the blends up to 40% arose the cure time and improved the physicomechanical and swelling properties. The optimal percentage was found to be 30% NR and 70% BR. Three formulations of natural [no 13], bromobutyl [no 14] and their blend [30NR-70BR] [no 18] were subjected to the suitability tests as parenteral stoppers. The results of aging indicated that the three elastomers possess good heat and oxidation resistance characteristics and are also suitable for sterilization. The suitability tests according to the international standards proved that the three elastomers have a suitable limits of physicomechanical and chemical properties

Effect of three rubber elastomers on the stability of amikacin and kanamycin in parenteral solutions

Three rubber elastomers [natural, bromobutyl and their blend] were prepared, exhibited good physicomechanical and chemical properties and suitable for use as parenteral stoppers. The effect of these elastomers on the stability of amikacin and kanamycin in solutions was investigated. The three elastomers were found to augment the loss of each antibiotic upon storage. The loss increased with time. The effect was more pronounced at 60C rather than at 25C. Bromobutyl elastomer showed the least determinative effect towards the antibiotic potency relative to the reference elastomer, as it exhibited the lowest sorption characteristics than the natural elastomer. Leached materials from rubber elastomers slightly affected the loss of antibiotics from solutions

Spectrophotometric determination of oxytetracycline by coupling with diazonium salts

Diazotized p-nitroaniline [I], sulfanilic acid [II] and sulfanilamide [III] were used for the spectrophotometric determination of oxytetracycline [OTC]. The procedure is based on the observation of that in slightly alkaline medium OTC reacts with I, II and III. A stable azo dye is formed and show maximum absorption at 550, 560, and 575 nm, respectively. The variable affecting development of the color have been investigated and the conditions optimized. Beer's law is obeyed for up to 25, 90 and 90 mug/ml on using I, II and III, respectively. Molar absorptivities [L mol-1 cm-1] and Sandell's sensitivities [mug cm-2 per 0.001 absorbance unit] are respectively; 0.83 x 104 and 57.8 x 10-3, 0.14 x 104 and 200 x 10-3 and 0.12 x 104 and 176.5 x 10-3. The mean percentage accuracies were 99.9 +/- 1.75, 99.95 +/- 0.71. The results obtained either in pure form or in pharmaceutical formulations are accurate and precise. The nature of the dye was discussed and the structure of a mono azo dye was suggested

Spectrophotometric studies on some azo compounds derived from tetracycline and oxytetracydine

The absorption spectra of some azo compounds derived from aniline, p- nitroaniline, sulfanilic acid and sulphanilamide coupled with tetracycline [TC] and oxytetracycline [OTC] in organic solvents and buffer solutions of different pH values have been investigated. The results have been utilized for the determination of pKa. The spectra of the compounds were discussed in relation to molecular structure

Indirect determination of glucose by atomic absorption spectrophotometry

Although atomic absorption spectrophotometry is commonly used for the direct determination of metals, the method is not suitable for the determination of organic substances. Various methods for the indirect determination of organic compounds are however used frequently 2-Hydroxynaphthoic acid has been determined indirectly through the selective extraction of the Ni [II] 2-Hydroxynaphthoate with nitrobenzene. Phthalic acid is extractable into methyl-isobutyl ketone as the ion pair formed between bis-[neocuproin] Cu [I] and the univalent anion of phthalic acid. A similar method has been employed for the determination of pentachlorophenol. Halonen and Aira were able to determine sugars by their depressive effect on the absorption of calcium. Sugar was also determined by atomic absorption Spectrophotometry after the reduction of CuSO[4] in a carbonate-tartarate solution. Berka et al. studied the oxidation of D-glucose by KMn0[4] in buffered and alkaline media. In the present investigation, and indirect method for the atomic absorption determination of glucose is developed based on the reaction with KMnO[4] under such conditions leading to the quantitative formation of MnO[2]. Both the unreacted KMnO[4] and formed MnO[2] are then determined by atomic absorption Spectrophotometry. Thus, the atomic absorption method for the determination of Mn is indirectly used for the determination of glucose

Effect of organic solvents on the determination of copper II by atomic absorption spectrophotometry and its utilization for estimation of kanamycin

Organic solvents were used as media for atomic absorption determination of metals in order to increase the sensitivity of the method. Ivanov and Kozyrava used propanol in the determination of copper. Other applications were given for determination of lead and palladium. The atomic absorption method has been used for indirect determination of pharmaceutical compounds. Kanamycin sulphate is a member of aminogl ucosides which complexes with cupric ions, through its amino group. Amino nitrogen compounds were also determined using the same technique by allowing these compounds to react with dissociated copper phosphate in alkaline medium. In the present paper, the effect of a large variety of solvents, including alcohols and ketones, on the estimation of copper or kanamycin by atomic absorption spectrometry, investigated

2-hydroxy naphthyl-1-azo-Bacetylacetone [HNAAA] as chelating agent for alkaline earth and bivalent metal ions of the first transition series

The members of a new series of [M [HNAAA]]. x H2O are prepared, where, M = Ca[2+], Mn[2+], Fe[2+], Co[2+], Ni[3+],Cu[2+], Zn[2+], Mg[2+] and Sr[2+] and [HNAAA] is 2-hydroxy naphtnyl-1-azo Beta- acetylacetone [a dibasic tridentate ligand]. The complexes are-Subjected to elemental micro analysis and characterized by ir, electronic and [1] H nmr spectra, DTA and x-ray analysis. The stability constants of the complexes formed are determined by potentiometric techniques and discussed in relation to the ionic potentials

Indirect determination of lactose by atomic absorption spectrophotometry

An indirect atomic absorption method for the determination of lactose is developed. Heptavalent manganese is reduced in weakly acidic solutions by lactose to form insoluble MnO2. The concentration of lactose in the solution is determined from a calibration curve prepared from measurements made on known amounts of lactose. In the meantime the quantity of MnO2 formed is proportional to the concentration of lactose added and the formed Mn[2+] ions are determined by atomic absorption spectrophotometry