Simultaneous Estimation of Cefixime and Ofloxacin in Bulk and ...

Asian J. Pharm. Ana. 2011; Vol. 1: Issue 2, Pg 36-38
[AJPAna.]
ISSN- 2231–5667 (Print)
ISSN- 2231–5675 (Online)
www.asianpharmaonline.org
RESEARCH ARTICLE
Simultaneous Estimation of Cefixime and Ofloxacin in Bulk and Tablet
Dosage Form
Rajendran S.S.*, Santhi N., Kumar Nallasivan P., Sam Solomon W.D., Venkata Narayanan R.
RVS College of Pharmaceutical Sciences, Sulur, Coimbatore
*Corresponding Author E-mail: ss.rajendra00@gmail.com
ABSTRACT:
Two simple, rapid, accurate and price spectrophotometric methods have been developed for simultaneous estimation
of cefixime and ofloxacin in bulk and in tablet dosage form. Method A involves simultaneous equations at 290.4 nm
(max of Cefixime) and 297.4nm (max of Ofloxacin). Method B involves Absorbance ratio method at 282.0 nm (isoabsorptive
point) and 297.4 nm (max of Ofloxacin) using ethanol as a solvent. The linearity was observed in the
concentration range of 5-25 g/ml for Cefixime and 2-10 g/ml for Ofloxacin. The results of analysis have been
validated statically and by recover studies and were found satisfactory.
KEYWORDS: Cefixime; Ofloxacin; Simultaneous equations; Absorbance ratio method.
INTRODUCTION:
Cefixime (CEFI) (6R, 7R)-7-[2-(2-amino-4- thiazolyl)
glyoxylamido]-8-oxo-3-vinyl-5-1-azabicyclo[4.2.0]oct-2-
ene-2-carboxylicacid,7-9z)-[o-carboxymethyl)-oxime]
trihydrates is third generation cephalosporin antibiotic 1 .
Ofloxacin (OFLO)chemically 9-fluoro-2,3-dihydro-3-
methyl-10-(4-methyl-piperazinyl)-7-oxo-7H-pyrido(1,2,3-
di)-1,4-benzoxazine carboxylic acid used as an antibacterial
and clinically used in the treatment of susceptible infections
including gonorrhea, otitis media, bronchitis, urinary tract
infections 2 . Literature survey reveals cefixime and ofloxacin
estimated by high performance liquid chromatographic
(HPLC) in tablet dosage form 3,5 . Spectrophotometric
method for simultaneous estimation of cefixime with other
drugs also reported 6 . spectrophotometric method for
simultaneous estimation of ofloxacin with other drugs also
reported 7 . No report was found for the simultaneous
estimation of cefixime and ofloxacin in bulk and tablet
dosage form by spectrophotometric method. Present work
describes a simple, accurate, rapid and economical methods
for simultaneous estimation of cefixime and ofloxacin in
bulk and in combined tablet dosage forms.
Received on 29.06.2011 Accepted on 30.06.2011
© Asian Pharma Press All Right Reserved
Asian J. Pharm. Ana. 1(2): April-June 2011; Page 36-38
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MATERIAL AND METHODS:
Reagents and Chemicals:
Ethanol (AR Grade) was used as solvent, procured from
Universal Laboratories private limited, Mumbai. Pure
Standard gift sample of cefixime provided by Glen mark
pharmaceutical Ltd, and Ofloxacin by Aristo
Pharmaceuticals Pvt. Ltd, Mumbai. Combined dose of
cefixime and ofloxacin tablets (label claim 200mg) were
purchased from local market.
Instrumentation:
A double-beam Elico UV-visible spectrophotometer, with
spectral bandwidth of 0.2nm, wavelength accuracy ± 0.1
nm and a pair of 1 cm matched quarts cells were used to
measure absorbance of the resulting solution.
Preparation of standard stock solution:
Standard stock solutions of cefixime (100g/ml) and
ofloxacin (40µg/ml) were prepared in ethanol and used for
the analysis.
Methods:
Method A: Simultaneous Equation Method
Simultaneous equations method based on measurements at
two wavelengths. Two dissimilar chromophores must
necessary have different powers of light absorption at some
points or in linear absorption.
A set of two simultaneous equations obtained by using
mean absorptivity values are given below
A 2 ay 1 -A 1 ay 2
C X = --------------------- -------------------- (1)
ax 2 ay 1 -ax 1 ay 2

Asian J. Pharm. Ana. 2011; Vol. 1: Issue 2, Pg 36-38
A 2 ay 1 -A 1 ay 2
C Y = --------------------- ---------------------- (2)
ax 2 ay 1 -ax 1 ay 2
Where, A1 and A2 are absorbance of the sample at 290.4nm
and 297.4 nm respectively, ax 2, ax 1 = denote absorptivities
of X at 290.4 nm and 297.4nm respectively, ay 1 ,ay 2 =
denote absorptivities of Y at 290.4 nm and 297.4nm
respectively, CX = concentration of cefexime; CY =
concentration of ofloxacin.
Method B. Absorbance Ratio Method:
It depends on the property that, for a substance which obey
Beers law at all wavelengths is constant value independent
of concentration or path length.
From the following set of equations the concentration of
each component in sample can be alculated.
For Cefixime:
Qm – Qy
A1
Cx = -------------- X ----- ---------------------- (3)
Q x – Qy a
For Ofloxacin:
Qm – Qx A1
CY= ------------- X ------ ---------------------- (4)
Qy – Qx a
Where, Cx = Concentration of Cefixime, CY =
Concentration of Ofloxacin, A1 = Absobance of sample at
iso-absorptive wavelength 282.0 nm, a = Mean absorptivity
of CEFI and OFLO at iso-absorptive 282.0 nm,
Absorbance of sample solution at290.4nm
Qm = ____________________________________
Absorbance of sample solution at 282.0 nm
Absorptivity of Cefixime at290.4 nm
Qx = ____________________________________
Absorptivity of Cefixime at 282.0 nm
Absorptivity of Ofloxacin at 297.4 nm
Qy = ____________________________________
Absorptivity of Ofloxacin at 282.0 nm
Spectral characteristics of CEFI and OFLO:
Solutions of CEFI and OFLO (10 g/ml, each), were
prepared separately by appropriate dilution of standard
stock solution. Both the solutions were scanned in the
spectrum mode from 400 nm to 200 nm. Overlay absorption
spectra were recorded (Fig. 1).
Preparation of calibration curves
Appropriate dilutions of the standard stock solution were
done separately to get 5,10,15,20, and 25 g/ml of CEFI
and 2, 4, 6, 8, and 10g/ml of OFLO. The absorption
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spectra of all solutions were recorded between 200-400 nm.
The absorbances were measured at 290.4 nm (max of
CEFI) 297.4 nm (max of OFLO) and 282.0 nm (isoabsorptive
point).Beer’s lamberts range for CEFI and
OFLO were selected and working calibration curves of both
the drugs were plotted separately.
Determination of Absorptivity Value of CEFI and
OFLO:
Appropriate dilutions of the standard stock solution were
done to get 10 g/ml of each CEFI and OFLO, respectively.
The absorbances were measured for CEFI and OFLO at
290.4 nm (max of CEFI), 297.4 nm (max of OFLO) and
282.0 nm (iso-absorptive point). The absorptivity values of
the drugs were determined at the selected wavelengths.
Assay of tablet formulation:
Twenty tablets were weighed and average weight was
calculated. The tablets were crushed to obtain fine powder.
Tablet powder equivalent to 100 mg of CEFI was
transferred to 100.0 ml volumetric flask, ethanol added,
ultrasonicated for 10 minutes and volume was made-up to
the mark with ethanol. The solution was then filtered
through a Whatman filter paper (No. 41). The filtrate was
further diluted with ethanol to obtain 10 g/ml of CEFI and
10 g/ml of OFLO. The concentration of both CEFI and
OFLO were determined by measuring the absorbance of the
sample at 290.4 nm, 297.4 nm Calculated using (method A,
simultaneous equation method) and (method B, absorbance
ratio method). Concentration of sample solution was
determined by using above equations1, 2,3 and 4.The
results are reported in the Table 1.
RESULTS AND DISCUSSION:
The present method could be provided a convenient and
accurate method for simultaneous analysis of CEFI and
OFLO. In simultaneous equation method, wavelengths
selected for analysis were 290.4nm (max of Cefixime) and
297.4 nm (max of Ofloxacin). In both the methods
linearity for detector response was observed in the
concentration range of 5-25 g/ml for CEFI and 2-10 g/ml
for OFLO. Absorptivity coefficient were calculated for both
the drugs at selected wavelengths and substituted in
equations for determining concentration of CEFI and OFLO
in tablet sample solution. Percent label claim for CEF and
OFLO in tablet analysis, by both the method was found in
the range of 98.54 % to 100.5%. Standard deviation and
coefficient of variance for six determinations of tablet
sample, by both the methods, was found to be less than ±
2.0 indicating the precision of both the methods. Accuracy
of proposed methods was determined by recovery studies.
The percent recovery for CEFI and OFLO, the methods was
found in the range of 98.19 % – 100.45 %. The developed
method could be employed for routine analysis of Cefixime
and Ofloxacin in combined dose tablet formulation.
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Table 1: Tablet Analysis and Recovery Studies of Cefixime and Ofloxacin
Method Label Claim (mg/tab) Amount Found (%) Standard Deviation % Recovery
CEFI OFLO CEFI OFLO CEFI OFLO CEFI OFLO
A 200 200 100.5 94.8 ±0.33419 ±0.2494 100.9±0.1647 95.2±0.1452
B 200 200 98.4 95.8 ±0.2487 ±0.1984 99.8±.6428 97.7±0.1587
Fig.-1: Overlain Spectra of Cefixime (CEFI) and Ofloxacin
(OFLO)
ACKNOWLEDGEMENTS:
The authors are grateful to RVS College of Pharmaceutical
Sciences, Coimbatore for providing necessary facilities.
REFERENCES:
1. WWW.Wikipedia.org/Wiki/Cefixime
2. Sweet man S.C., Martindale. The complete Drug Reference. 32nd
Edn. Pharmaceutical press.
3. WWW.Wikipedia.org/Wiki/ofloxacin
4. Zendelovska D.,Stafilov T., Milosevski P.“High performance
liquid chromatographic method for determination of cefixime and
cefotaxime in human plasma”. Bulletin of the chemists and
Technologists of Macedonia.2003;22: 39-45.
5. Rathinavel G., Mukherjee P. B., Valarmathy J., Samueljoshua
L., Sivakumar T. “A Validated RP – HPLC method for
simultaneous estimation of cefixime and cloxacillin in tablets”
Journal of chemistry.2008; 5: 648-651.
6. Jovanovic E. S., Agbaba D. ZivanovStakic S. “HPTLC
determination of csftriaxone;cefixime and cefotaxime in dosage
forms” J. Pharm. Biomed. Anal. 1998; 18: 893898.
7. Senthilraja M. “Simultaneous UV spectrophotometric method for
estimation of nitazoxanide and ofloxacin in combined dosage
form”. Int. J. Pharm. Tech. 2008; 1: 469-471.
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