CHEMOMETRICS ASSISTED UV-SPECTROPHOTOMETRIC ...

4. RESULT AND DISCUSSION
4.1. Preliminary investigation of data structure in chemometrics techniques
The original laboratory (experimental) observations are taken as a row data and well
tabulated systematically for the mathematical, statistical and computer software analysis
purpose.
The pure benzoic acid, salicylic acid and resorcinol data are tabulated, discussed and
analyzed first (calibration step). Next to pure forms the laboratory-prepared mixtures with
different ratios are treated accordingly (testing step). Eventually the dosage form
(commercial) mixtures are analyzed (prediction step).
The experiments were done in triplicates in all cases in different three days with the same
procedure, laboratory equipment, time and analyst (to confirm both repeatability and
reproducibility precisions). Then the mean averages of the triplicates for every day and all the
three days are then taken in this analysis. Subsequently various graphs are sketched from the
tabulated data using different software such as MS Excel, Harvard Graphics 2.0 and Vista
6.0.
These preliminary graphs may help us in reaching a final conclusion about the data structure
and the proper selection of the used analytical method:-
1. Overlay plots of the given spectra:-
This will make apparent gross outliers and clear clusters in the given responses (absorption in
our case) Figures 10-12, represent the overlay plots for the standard compounds (benzoic
acid, salicylic acid, and resorcinol respectively) at the different concentration levels.
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