INTRODUCTION:

Ciprofloxacin is a broad spectrum antibiotic active against gram +ve and gram –ve bacteria. It functions by inhibiting DNA gyrase [1,2], a type 2 topoisomerase and type IV, enzymes necessary to separate bacterial DNA, there by inhibiting cell division[2,4]. Ciprofloxacin is chemically 1-cyclopropyl-6- fluoro- 4-oxo- 7-(piperazin-1-yl)-quinoline -3-carboxylic acid [5, 7]. Literature survey reveals that no method has been reported for estimation of ciprofloxacin satisfactorily. In The present investigation an attempt has been made to develop a simple accurate, reproducible and economical spectrophotometric method for the estimation of ciprofloxacin in tablet dosage form.

EXPERIMENTAL:

Material and methods:

Elico SL210 uv-vis double beam spectrophotometer with a pair of 1cm matched quartz cells was used. Shimadzu BL- 220H analytical balance, Ciprofloxacin (Aurabindo pharma Ltd.) and methanol of AR grade (S.D fine chemicals) was used for the study.

Preparation of stock solution:

Standard stock solution was prepared by dissolving 10 mg of drug in 10 ml of distilled water to get concentration of 1000µg/ml solution. The stock solution was further diluted with distilled water to get working standard solutions of 100µg/ml and 10µg/ml. to construct beer’s lamberts plot for pure drug, different aliquots of ciprofloxacin were taken and diluted to 10ml with distilled water. The absorbance was measured maximum at 273nm against distilled water as blank. The drug has obeyed beer’s limit in the concentration range 5-60µg/ml.

Table 1: Linearity table of ciprofloxacin in distilled water

Concentration (µg/ml)	Absorbance
5	0.362
10	0.721
20	1.412
30	2.113
40	2.802
50	3.600

Calibration curve of ciprofloxacin

Estimation of ciprofloxacin in commercial formulations

For analysis of commercial formulations, 20 tablets containing ciprofloxacin taken and powdered. The powder equivalent to 10mg of ciprofloxacin was taken in a 100ml volumetric flask, containing 70ml of distilled water and sonicated for 30 minutes. The volume was made up to 100 ml with distilled water and filtered to get a concentration of 100µg/ml. This was further diluted with distilled water to get a concentration within the linearity range. The values are substituted in regression equation to get the percentage purity. The percentage purity found to be 101.2%.

Table 2: RECOVERY TABLE

Formulation	Labeled amount	Observed amount	% Recovery	%RSD
Brand-I	500mg	506±0.33	101.2%	4.612
Brand -II	500mg	504±0.33	100.8%	3.999

Table 3: PRECISION

Concentrations (µg/ml)	Absorbance at 273nm	Statistical analysis
10	0.761	MEAN=0.7255
10	0.753	MEAN=0.7255
10	0.702	S.D=0.334664
10	0.732	S.D=0.334664
10	0.696	%RSD=4.612
10	0.709	%RSD=4.612

Table 4: ACCURACY

Samples	Concentration(µg/ml)		% Recovery	Statistical analysis
Samples	Pure drug	Formulation	% Recovery	Statistical analysis
80%	8	10	93%	MEAN=96 SD=3.6 %RSD=3.75
80%	8	10	100%
80%	8	10	95%
100%	10	10	97%	MEAN=91 SD=6.55 %RSD=7.197
100%	10	10	96%
100%	10	10	90%
120%	12	10	94%	MEAN=96 SD=3.46 %RSD=3.604
120%	12	10	100%
120%	12	10	94%

Table 5: OPTICAL CHARECTERISTICS:

OPTICAL CHARECTERS	At 273nm
Beer’s law limit (µg/ml)	5-50 µg/ml
%RSD	4.612
Correlation coefficient	0.999
Slope (a)	0.071
Intercept (b)	0.004
Regression equation	Y=0.071x-0.004

RESULTS AND DISCUSSION:

The proposed method for estimation of ciprofloxacin dosage form was found to be accurate, simple and rapid. The calibration and assay results were shown in table 1-5. The % RSD is found to be less than 4, which indicates the validity of method. Linearity was observed by regression equation for ciprofloxacin in different concentration range. The assay results obtained by proposed method were precise; hence it can be used for routine analysis of ciprofloxacin dosage form. There was no interference from tablet excipients in this method. The method is accurate, simple, rapid, precise, reliable, sensitive, reproducible and economic and is validated as per ICH guidelines.

CONCLUSION:

Thus the proposed method for the estimation of ciprofloxacin in the tablet dosage forms was found to be rapid, sensitive, simple, accurate, and economical. High percentage of recovery shows that the method is free from the interference of excipient (s) used in formulation. Therefore the method can be useful in routine quality control of these drugs. The method was accurate and having good prescion value.

REFERENCES:

1. Drusano GL, Standiford HC, Plaisance K, Forrest A, Leslie J, Caldwell J, GL (Sept 1986) “Absolute oral bioavailability of ciprofloxacin” Anti microbe agents’ chemother. 30 (3): 444-6.

2. “Ciprofloxacin- Hydrochloride”. The American Society of Health-system Pharmacists. Retrived 3 April 2011.

3. “Flouroquinolone drug class review”. Oregon State University college of Pharmacy 2002. Retrived Sept 9, 2011.

4. Gomes GC, Salgado HRN. Validation of UV Spectrophotometry method for determination of Lomifloxacin in pharmaceutical dosage form. Acta Farm. Bonaerense, 2005; 24 (3): 406-408.

5. Ross DL, Riley CM. Antibacterial effect of Nalidixicacid derivatives. Intl. J. Pharm., 1990; 63: 237-240.

6. Macor JE. Annual Report in Medicinal Chemistry, Vol 21. London: Academic Press, 2007; p 331.

7. Guidance for industry bioanalytical method validation. U.S Dept. of Health and Human Services May 2001.

Received on 13.10.2012 Accepted on 12.11.2012

Asian J. Pharm. Ana. 2(4): Oct. - Dec. 2012; Page 116-117