cefoxitin and cefamandole-nafate

A sensitive, accurate, precise and the same time simple and rapid method for the colorimetric determination of some cephalosporins of the second and third generations, such as: cefoxitin sodium (CFXT), cefaclor (CFCL), cefamandole nafate (CFMD), ceforanide l-lysine (CFRN), cefotaxime sodium (CFTX), and cefurozime sodium (CFRX) was described. The new method proposed is based: a) On the reduction of Fe(III) to Fe(II) by the drug analysed and b) On complexation of Fe(II) formed with o-Phenanthroline (O-Phen) consistently the formation of the well known highly stable orange-red coloured chelate complex [Fe(II)-(o-Phen)3]2+ which exhibits an absorption maximum at lambda = 510 nm (pH 4.50 +/- 0.2). Beer's law is obeyed for: 1.0 - 37.5 microgram mL-1 for CFX, 1.0 - 25.0 microgram mL-1 for CFMD, CFRN, and CFTX and 2.0 - 37.5 microgram mL-1 for CFTX and CFCL, while the apparent molar absorptivity ( epsilon in L mol-1cm-1) and the Sandell's sensitivity in (ngcm-2) both referred to the drug analyzed, are 1.29 x 10(4); 34.7 (CFXT), 7.61 x 10(3); 50.7 (CFCL), 3.33 x 10(4); 15.4 (CFMD), 2.60 x 10(4); 17.6 (CFRN) respectively. The regression line equation for each one of the above studied cephalosporins were calculated with a correlation coefficient 0.9997 < r < 1.0000; the accuracy and the precision of the method was considered as very satisfactory, while the results of a statistical analysis by means of the Student's t-test and the variance ratio F-test prove that no significant difference was observed between the results of the proposed method and those of official one.

Topics: Cefaclor; Cefamandole; Cefotaxime; Cefoxitin; Cefuroxime; Cephalosporins; Colorimetry; Indicators and Reagents; Molecular Structure; Sensitivity and Specificity

High-pressure liquid chromatographic (HPLC) methods for the quantitative determinations of cefamandole, cefamandole nafate, and cefoxitin sodium were developed and used to study the stabilities of reconstituted solutions of the latter two antibiotics. Results from the HPLC procedures were compared with those from a previously reported colorimetric procedure. Solutions (2%) of cefamandole nafate and cefoxitin sodium in 0.9% sodium chloride injection and in 5% dextrose injection were studied at 24 degrees C and 5 degrees C. The colorimetric method, which is supposed to be specific for compounds with beta-lactam rings, gave misleading results because of the hydrolysis of the antibiotics. The results obtained by HPLC were reproducible and the procedure separated cefamandole, the hydrolyzed compound, from its ester (cefamandole nafate), which was essential for conducting these studies. The cefamandole solutions were stable for approximately five days at 24 degrees C and 44 days at 5 degrees C. The cefoxitin solutions were stable for 24 hours at 24 degrees C and for at least 13 days at 5 degrees C.

Topics: Cefamandole; Cefoxitin; Cephalosporins; Chromatography, High Pressure Liquid; Colorimetry; Drug Stability; Hydrolysis; Solutions; Temperature