USING MINITAB

By: CHETAN DHALM.Pharm III Sem (QA)

Deptt of PharmaceuticsF/O Pharmacy

Jamia HamdardN.Delhi - 110062

MINITAB FOR OPTIMIZATION OF CONDITIONS• For the purpose there are several designs viz a) Factorial designb) Response surfacec) Mixtured) Taguchi• Different design have different applications. Usually for optimization of

analytical method CCD (central composite design) under the category Response surface suits best. • The reason behind using this method is that it helps in covering the central

points; axial points; and the far off points so that a circle form covering the axial points.

Open minitab and do to create response surface design and select.

Select central composite design; one can change the no of factors by clicking the arrow it represents the no of factors to be analyzedSelect and open Display available designs; click oK; select and open designs and click ok. After this the rest of 3 option enables. Click on factors and put the names just by selecting A and B; add specific values against the columns in front of them and click OK.

After clicking OK to the factor dialog box. Click ok to the main dialog box. A work sheet will appear.

One can double click the “worksheet 1 **” bar to enlarge the worksheet

Suppose you have 3 response to be optimized based on the 2 factors previously selected. Add Response A; Response B; Response C to the work sheet by selecting suitable column after factor B. Add specific values to these responses

Once you have finished adding responses to the work sheet you need to analyze them. Go to stat then DOE then Response surface and select analyze response surface designs.

NOTE: THIS OPTION WILL ENABLE SUCCESSIVELY. IN THE START OF EXPERIMENT THIS REMAINS DISABLED

One by one select all the responses. Go to graph and select four in one type. Click OK. Different graphs will appear.

• Now go to the option OVERLAID CONTOUR PLOT and select. A window appears. Click the button with 2 arrow if you wish to optimize all the responses other wise select particular ones. Now go to the option contours. This dialog box will appear and put desired lower and higher limits and select OK.

Clicking ok will generate something called as overlaid contour plot. The white zone is design space and grey zone is undesired space. Select any point in desired space it will give results referring to the limits set while generating overlaid contour plot.

One can also optimize the conditions by selecting response optimized in the response surface list.

• Select all the factors by clickin n double arrow button. This will enable setup button. Click on setup button. Another window appears.

Set goal; give values to the responses and click ok.

After clicking ok a optimized condition with maximum desirability appears. These are the optimized conditions

This completes understanding Response surface design for optimization

THANK YOU