A drug is a compound that have medicinal, intoxicating, performance enhancing or other effects when taken or put into a human body or the body of another animal and is not considered a food or exclusively a food. There was no single, precise definition, as there are different meanings in drug control law, government regulations, medicine, and Colloquial usage. Pharmaceutical drugs are used for the determination of their quality assurance and quality control of bulk drugs and their formulations. Qualitative analysis provides the chemical identification of the sample, and establishment of the relative amount of one or more of the species or analytes in numerical terms. In Chromatography, Adsorption chromatography employs high-surface area particles that adsorb the solute molecules. Usually a polar compound such as a silica gel, alumina or porous glass beads and a non-polar mobile phase such as heptane, octane or chloroform are utilized in adsorption chromatography. In adsorption chromatography, adsorption process is defined by competition model and solvent interaction model. In partition chromatography, the solid support was coated with a liquid stationary phase; the relative distribution of solutes between the two liquid phases determines the separation. The stationary phase can be either polar or non polar compound. If the stationary phase was polar and the mobile phase was non polar, it is known as normal phase partition chromatography. If the stationary phase was non polar and the mobile phase was polar, it is known as reverse-phase partition chromatography

METHOD DEVELOPMENT:

Selection of Detection wavelength:

10 mg of Aluminium hydroxide and Simethicone was placed in Phosphate buffer which is a mobile phase. That solution was scanned at 200-400 nm for determination of spectrum.  The excessively spectrum was used for selection of wavelength for Aluminium hydroxide and Simethicone.

Selection of column:

Column is selected on the bases of solubility, polarity and chemical differences among Analytes [Column: Inertsil C18 (4.6 x 250mm, 5µm, Make: Waters)]

Selection of mobile phase:

Phosphate buffer (0.05M) pH 4.6: ACN (30:70%v/v) was used as mobile phase.  The pH of the buffer should be 2 to 8. 

Selection of flow rate:

Flow rate is selected based on

1. Retention time              

2. Column back pressure      

3. Peak symmetry       

4. Separation of impurities

Preparations and procedures:

Preparation of Phosphate buffer :( PH: 4.6):

Accurately 6.8 gm of KH2PO4 weighed and placed into a 1000ml beaker, dissolved and diluted with 1000ml with HPLC water, adjusted the pH to 4.6 with orthophosphoric acid.

Preparation of mobile phase:

300mL of pH 4.6 Phosphate buffer (30%), 700mL of ACN (70%) are mixed and degassed in ultrasonic water bath for 5 minutes. Then this mobile phase was filtered under vacuum filtration.

Preparation of the individual Aluminium hydroxide standard preparation:

10mg of Aluminium hydroxide was accurately weighed and transferred into a 10ml clean dry volumetric flask and about 2ml of DMF was added. Then the preparation was sonicated to dissolve completely and made the volume up to the mark with the diluant.  Then 10 ml of the solution was pipette out into a 100 ml volumetric flask and was diluted up to the mark with diluant.

Preparation of the individual Simethicone standard preparation:

10mg of Simethicone was accurately weighed and transferred into a 10ml clean dry volumetric flask and about 2ml of DMF was added. Then the preparation was sonicated to dissolve completely and made volume up to the mark with the diluant. Then 10ml of solution was pipette out into a 100 ml volumetric flask and was diluted up to the mark.

Accuracy:

Preparation of standard solution (Aluminium hydroxide and Simethicone):

Accurately weighed 10mg of Simethicone and 10mg of Aluminium hydroxide and transferred into 100ml of clean dry volumetric flasks. 70ml of Diluent was added and sonicated to dissolve the drug completely and made volume up to the mark with the same solvent. Then 3ml of the solution was pipette out into a 10ml volumetric flask and make up to the mark with diluent.

Preparation of Sample solutions:

For preparation of solution:

Accurately weighed 5mg of Simethicone and 5mg of Aluminium hydroxide and transferred into 100ml of clean dry volumetric flask. 7ml of diluent was added and sonicated to dissolve the drug completely and made volume up to the mark with the same solvent. Then 3ml of the Simethicone and Aluminium hydroxide solution were pipette out into a 10ml volumetric flask and diluted up to the mark with diluant.

Acceptance criteria

Correlation coefficient could be not less than 0.999

Linearity

Preparation of stock solution:

Procedure:

The solution was injected into the chromatographic system and the peak area was observed, a graph of peak area versus concentration (on X-axis concentration and on Y-axis Peak area) was plotted and the correlation coefficient was measured. 

Acceptance criteria

Correlation coefficient could be not less than 0.999.

RESULTS AND DISCUSSION

WAVELENGTH DETECTION:

The detection wavelength was selected by dissolving the drug in mobile phase to get a concentration of 10?g/ml for individual and mixed standards. The resulting solution was scanned in U.V range from 200-400nm.  The overlay spectrum of Aluminium hydroxide   and Simethicone was obtained and the isobestic point of Aluminium hydroxide   and Simethicone showed absorbance’s maxima at 260 nm.

Fig. 01: Overlay spectrum of Aluminium hydroxide and Simethicone

 Accuracy:

Accuracy study was performed for Aluminium hydroxide and Simethicon, solution injected in triplicate into chromatographic system results were shown in table 01, 02.

Table 01. Accuracy results of Simethicone

Acceptance Criteria:

The % Recovery for each level should be between 98.0 to 102.0%.

The accuracy results for Aluminium hydroxide 

Table 2. Accuracy results of Aluminium hydroxide

Acceptance Criteria:

The % Recovery for each level should be between 98.0 to 102.0%.

Precision

Repeatability

The precision studies were performed by injections of Aluminium hydroxide and Simethicone was injected in to chromatographic system. The area of standard injection was determined by calculation of % RSD.

Fig 2. Chromatogram of Standard Injection

Table: 03, 04 Ruggedness results of Simethicone& Aluminium hydroxide

Acceptance Criteria:

The % RSD for the area of five standard injections results could not be more than 2%.

Specificity:

The system suitability for specificity was performed to determine that there is any interference of any impurities in retention time of analytical peak the studies was carried out by injecting blank, standard and sample solution results are shown in table no: 5, 6 respectively.

Table 5 Standard results of Simethicone& Aluminium hydroxide

Table 6.  Sample results of Simethicone& Aluminium hydroxide

Detection of limit:

LOD’s can be measured based on the standard deviation of the response (SD) and the slope of the calibration curve at levels approximating the LOD according to the formula.  The standard deviation of the response can be determined based on the standard deviation of y-intercepts of regression lines.

Fig. 3 Chromatogram of LOD

Fig.4. Chromatogram of LOQ

Linearity:

The linearity studies were determined for the concentration of 100ppm to 500ppm and 1ppm to 5ppm level each level was injected into chromatographic system.

Table 7 Linearity results of Aluminium hydroxide   and Simethicone

Acceptance Criteria:

Correlation coefficient should be not less than 0.999

Plotting of calibration graphs:

Linearity peaks are plotted against Concentration

Fig. 5 Calibration curve of Simethicone

Fig.6 Calibration curve of Aluminium hydroxide

System suitability results for Simethicone:

Table  8. System suitability results for Simethicone

System suitability results for Aluminium hydroxide :

Table 9. System suitability results for Aluminium hydroxide

CONCLUSION