Estimation of Cefixime Trihydrate and Ofloxacin in
Combined Dosage Form by UV-Spectrophotometric Methods.
Patel A.N.*, Patel H.U., Patel C.N. and Jayswal U.P.
Department of Quality Assurance, Shri Sarvajanik
Pharmacy College, Mehsana-348001, India.
*Corresponding Author E-mail: ankit0508pharm@gmail.com,
ankit_143rose@yahoo.co.in
ABSTRACT:
Two
simple, sensitive, rapid, precise UV spectrophotometric methods have been
developed and validated for simultaneous estimation of Cefixime Trihydrate and
Ofloxacin. Recently this combination was approved for treatment of typhoid
fever and urinary tract infection in adults, which is available in tablet
dosage form. First method is simultaneous equations method, wavelength selected
for estimation of Cefixime Trihydrate and Ofloxacin are 289 nm and 298 nm
respectively. The second method is first order derivative method based on measurement
at zero crossover point of another drug, measurement of Cefixime Trihydrate and
Ofloxacin were carried out at 297.8 and 288 nm respectively. The linearity was
obtained in the concentration range of 3-15 µg/ml of both the drugs. The
proposed methods are successfully applied for the simultaneous determination of
both drugs in commercial tablet preparation. The method was validated with
respect to linearity, accuracy and precision as per the International
Conference on Harmonisation (ICH) guidelines.
KEYWORDS: Cefixime Trihydrate, Ofloxacin, simultaneous
equations, first order derivative.
INTRODUCTION:
Cefixime
(CEF) (6R,7R) ‐7‐[2‐(2‐amino‐4‐thiazolyl)glyoxylamido]‐8‐oxo‐3‐vinyl‐5‐thia ‐1‐azabicyclo [4.2.0] oct‐2‐ene‐2‐carboxylic acid, 7‐(Z)‐[o‐(carboxymethyl)‐oxime]
trihydrate is a third‐generation cephalosporin antibiotic1.
Ofloxacin (OFL) chemically 9‐fluoro‐2, 3‐dihydro‐3‐methyl‐10‐(4‐methyl‐1piperazinyl)‐ 7‐ oxo‐7H‐pyrido (1, 2, 3‐di)‐1, 4‐benzoxazine
carboxylic acid is a second generation fluoroquinolone used as an antibacterial2-3.
Recently this combination has been approved for the treatment of patients with
typhoid fever and urinary tract infection in adults.
Literature
review reveals that many HPLC, HPTLC and Spectrophotometric methods have been
reported for CEF and OFL individually and combination with other drugs4-19.
Also HPLC and HPTLC method has been reported for CEF and OFL in their combined
dosage form20-21.
To
the best of our knowledge, no study has been described for the simultaneous
determination of both drugs in combined dosage form by UV spectrophotometric
method.
The
present paper described two simple, rapid, economic methods for simultaneous
estimation of CEF and OFL by simultaneous equation method and first order
derivative method. The proposed methods were validated as per International
Conference on Harmonization (ICH) guidelines Q2 (R1).
MATERIALS AND METHOD:
Equipment:
The
Shimadzu UV-Visible Spectrophotometer model 1700 was employed. The sample
solution was recorded in 1 cm quartz cell against solvent blank over the range
200-400 nm. The optimal condition for recording spectra to achieve good
reproducibility include medium scan speed, and slit width at 2 nm.
Material:
Pure
gift sample of CEF and OFL from Orchid Chemicals and Pharmaceuticals Ltd. were
used. All analytical grade chemicals and solvent were supplied by Loba Chemi
Pvt. Ltd. ZIMNIC_O 200 (Piramal Healthcare, Mumbai) tablets used for the study
were purchased from the market.
Procedure:
Standard
solutions and calibration curve:
Stock
solutions for spectrophotometric measurements were prepared by dissolving CEF
and OFL in methanol to obtain concentration of 1 mg/ml. Aliquots of the
standard stock solution were transferred to a series of 10 ml volumetric flask
and serially diluted with methanol to give varying concentrations ranging from
3-15 µg/ml for CEF and OFL. The solutions were scanned in the wavelength range
200-400 nm.
Sample
solution:
Twenty
tablets were weighed, powdered and weighed accurately equivalent to 10 mg of
CEF and OFL both and were transferred to a 100 ml volumetric flask and
dissolved in 50 ml of methanol by ultra-sonication for 20 min. The solution was
diluted with same solvent, filtered through Whatmann No.41 filter paper. The
filtrate was diluted with methanol to get final dilution 5 µg/ml of each drug.
Method
I: Simultaneous equation method:
From
Overlain spectrum; two wavelengths selected were 289 nm for CEF and 298 nm for
OFL (figure 1). (A1%, 1 cm) was calculated for each drug from absorbance values
at selected wavelengths. Simultaneous equations were constructed from
calculated absorptivity value.
Absorbance
of sample solution was measured at selected wavelengths as A1 and A2
and concentration of the two drugs in sample was calculated by using
following equation.
𝐶𝑥 =
……………………………… (1)
𝐶𝑦 =
……………..…………..…… (2)
Where,
A1 and A2 are the absorbances of
mixture at 289.0 nm and 298.0 nm respectively,
ax1 and ax2 are absorptivities of
CEF at 289.0 nm and 298.0 nm respectively,
ay1
and ay2 are absorptivities of OFL at 289.0 nm and 298.0 nm
respectively.
Figure
1: Overlain zero order spectra of Cefixime Trihydrate and Ofloxacin (5µg/ml).
Method
II: First-Order Derivative Spectroscopy:
The
spectrums obtained in method I was derivatised to obtain first derivative
spectrum. In overlain spectra CEF showed zero crossing at 288 nm while OFL
showed zero crossing at 297.8 nm (Fig-2). At the zero crossing point of CEF
(288 nm), OFL showed a substantial dA/dλ, whereas at the zero crossing
point of OFL (297.8 nm), CEF showed a substantial dA/dλ. Hence the
wavelengths 288 nm and 297.8 nm were selected as analytical wavelengths for
determination of OFL and CEF, respectively. These two wavelengths can be
employed for the estimation of OFL and CEF without any interference from the
other drugs in their combined formulation. Calibration curves were plotted by
taking dA/dλ on Y-axis and concentrations on X-axis. Spectrum of sample also
derivatized and absorbance of both drug were measured at selected wavelengths
and concentration of both drug calculated from calibration curve.
Figure
2: Overlain first order derivative spectra of Cefixime Trihydrate and
Ofloxacin.
RESULT
AND DISCUSSION:
CEF and OFL both drugs are insoluble in water but
soluble in methanol; hence methanol was selected as solvent. Zero-order overlain spectra of CEF and OFL (5 μg/ml of each) showed λmax
for CEF and OFL 289 nm and 298 nm respectively. Also both absorb at the
λmax of the other hence, simultaneous equation method was used to estimate
CEF and OFL in presence of each other. For first order derivative method zero
crossing was used.
Table 1: Statistical parameter
|
Parameter
|
Method I
|
Method II
|
|
OFL
|
CEF
|
OFL
|
CEF
|
|
Regression Equation
|
Y
= 0.1025x + 0.0169
|
Y
= 0.0448x + 0.0048
|
Y = 0.003x + 0.000
|
Y = 0.001x - 0.000
|
|
Correlation Co-efficient
|
0.9979
|
0.9996
|
0.9969
|
0.9989
|
|
Precision (%RSD)
|
|
Intraday
|
0.18
- 0.92 %
|
0.68
- 1.02 %
|
0.12 - 0.65 %
|
0.34 - 0.66 %
|
|
Interday
|
0.23
- 1.11 %
|
1.41
- 1.57 %
|
0.34 - 0.86 %
|
0.69 - 1.24 %
|
|
Accuracy
|
98.15
– 101.14 %
|
98.77
– 101.93 %.
|
99.06 – 100.88 %
|
100.14 – 101.24 %
|
Table 2: Analysis of Tablet formulation
|
Method
|
DRUG
|
Label claim
|
% Label claim estimated
(mean *± S.D.)
|
|
Simultaneous equation method (Method I)
|
CEF
|
200 mg
|
98.80±0.69%
|
|
OFL
|
200 mg
|
103.02±1.04 %
|
|
First order derivative
(Method II)
|
CEF
|
200 mg
|
99.80 ±0.60 %
|
|
OFL
|
200 mg
|
101.05±0.74 %
|
*Average of five determinations.
Both the methods were validated
statistically as per ICH guideline for parameters like linearity, precision and
accuracy. The values of coefficient of variation were satisfactorily low.
Accuracy was performed by recovery study at three level 80%, 100%, and 120% of
the test concentration. The RSD values for intraday and interday precision are
less then 2%. The recovery was between 98-102%. So the developed method is
accurate and precise. All data are as shown in Table 1. The amounts in terms of
% label claim obtained by proposed methods are presented in Table 2.
CONCLUSION:
The described methods give accurate and precise results
for determination of CEF and OFL mixture in tablets. The method was found to be
simple, accurate, economical, reproducible and rapid. Hence, it can be
employed for quality control of these two drugs in combined tablets.
REFERENCES:
1) www.wikipedia.org/wiki/Cefixime
2)
www.wikipedia.org/wiki/Ofloxacin
3) Sato K, et al. In-vitro and in-vivo activity of DL-8280
(or ofloxacin), a new oxazine, antimicrobial agents. Chemother. 23; 1982:
548-553.
4) Nanda RK et al. Simultaneous spectrophotometric
estimation of Cefixime and Ornidazole in tablet dosage form. International
Jounal of Pharmatechnolgical Reseach. 1(3); 2009: 488-91.
5) Shah PB, Pundarikakshudu K. Spectrophotometric,
difference spectroscopic and high-performance liquid chromatographic methods
for the determination of Cefixime in pharmaceutical formulations. American
Journal of analytical chemistry. 89(4); 2006: 987-94.
6) Muhammad H et al. Development of HPLC-UV method for
Analysis of Cefixime in Raw Materials and in Capsule. Jordan Journal of
Pharmaceutical Sciences. 2(1); 2009: 53-65.
7) Rathinavel G et al. A Validated RP – HPLC method for
simultaneous estimation of Cefixime and Cloxacillin in tablets. E-Journal of
Chemistry. 5(3); 2008: 648-51.
8) Khan IU et al. Simultaneous determination of Potassium
clavulanate and Cefixime in synthetic mixtures by high-performance liquid
chromatography. Journal of AOAC International. 91(4); 2008: 744-9.
9) Eric-Jovanovic S et al. HPTLC determination of
ceftriaxone, cefixime and cefotaxime in dosage forms. Journal of
Pharmaceutical and Biomedical Analysis.18; 1998: 893-8.
10) Pawar S et al. HPTLC Estimation of Cefixime and
Cloxacillin in Tablet Dosage Form. Asian journal of research in chemistry. 03(02); 2010: 299-301.
11) Bhusari KP, Chaple DR. Simultaneous Spectrophotometric
Estimation of Ofloxacin and Ornidazole in Tablet Dosage Form. Asian journal of
research in chemistry. 2(1); 2009: 60-2.
12) Wankhede SB et al. Simultaneous Spectrophotometric
Estimation of Ofloxacin and Satranidazole in Tablet Dosage Form. Asian journal
of research in chemistry. 1(1); 2008: 9-11.
13) Fegade JD et al. Simultaneous Spectrophotometric
Estimation of Ofloxacin and Ketorolac Tromethamine in Ophthalmic Dosage Form.
International Journal of ChemTech Research.1(2); 2009: 189-94.
14) Vinay et al. Spectrophotometric determination of
ofloxacin in pharmaceuticals and human urine. Ecl. Quím São Paulo. 34(4); 2009:
65-78.
15) Kuma S et al. Simultaneous RP-HPLC Estimation of
Nitazoxanide and Ofloxacin in Tablet Dosage Forms. Asian journal of research in
chemistry. 2(1); 2009: 43-5.
16) Godse VP et al. Validated stability-indicating hplc
method for simultaneous estimation of ofloxacin and satranidazole from
pharmaceutical dosage form. International Journal of Applied Biology and
Pharmaceutical Technology. 1(3); 2010:
1220-9.
17) Shakya AK et al. Development and Validation of an
RP-HPLC Method for Simultaneous Analysis of Ofloxacin and Ornidazole in
Tablets. Jordan Journal of Pharmaceutical Sciences. 3(2); 2010: 87-99.
18) Singh R et al. Simultaneous Estimation of Ciprofloxacin
Hydrochloride, Ofloxacin, Tinidazole and Ornidazole by RP-HPLC. Eurasian
Journal Analytical Chemistry. 4(2); 2009: 161-7.
19) Gandhimathi M et al. Validated high performance thin
layer chromatography method for simultaneous estimation of ofloxacin and
ornidazole in tablet dosage form. Indian Journal of Pharmaceutical Science. 68;
2006: 838-40.
20) Gandhi SV et al. A Simple and Sensitive RP-HPLC Method
for Simultaneous Estimation of Cefixime and Ofloxacin in Combined Tablet Dosage
Form. International Journal of Pharmacy
and Pharmaceutical Sciences. 3(1); 2011: 46-48.
21) Gandhi SV et al. High Performance Thin Layer
Chromatographic determination of Cefixime and Ofloxacin in combined tablet
dosage form. Journal of Chemical and Pharmaceutical Research. 2(5); 2010:
92-96.