CHEMOMETRICS ASSISTED UV-SPECTROPHOTOMETRIC ...
CHEMOMETRICS ASSISTED UV-SPECTROPHOTOMETRIC ...
CHEMOMETRICS ASSISTED UV-SPECTROPHOTOMETRIC ...
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Table 14. Actual and predicted amounts of salicylic acid (SA) and resorcinol (RE) given by<br />
applying CLS spectrophotometric techniques for pure, synthetic mixtures, Dorin emulsion,<br />
and Luna soap. (250 nm-400 nm)<br />
Component<br />
analyzed<br />
Pure<br />
component<br />
SA Conc.<br />
Found RE conc. Recovery<br />
used (µg/ml)<br />
Conc.used<br />
µg/ml (%) ∗ RSD µg/ml µg/ml (%) ∗<br />
RSD<br />
5 5.25 106.8 5.0 5 5.28 105.7 2.0<br />
10 9.78 100.2 5.1 10 10.28 102.8 1.9<br />
15 14.85 99.8 0.9 15 15.27 101.8 0.2<br />
20 20.41 103.1 3.9 20 20.54 102.7 0.4<br />
25 23.67 97.1 2.2 25 25.11 100.4 0.3<br />
30 30.71 101.8 1.0 30 30.15 100.5 1.6<br />
35 35.03 99.5 0.4 35 35.06 100.2 0.8<br />
40 40.66 101.2 1.1 40 40.15 100.4 1.5<br />
45 45.49 100.9 0.9 45 44.90 99.7 0.8<br />
50 49.15 98.2 0.7 50 49.42 98.8 0.1<br />
Synthetic<br />
mixtures<br />
Dorin<br />
10(5)<br />
10(10)<br />
5(10)<br />
10.23<br />
10.45<br />
5.17<br />
99.7<br />
101.5<br />
100.8<br />
3.3<br />
1.0<br />
0.6<br />
5(10)<br />
10(10)<br />
10(5)<br />
4.98<br />
10.14<br />
10.19<br />
99.5<br />
101.4<br />
101.9<br />
3.2<br />
2.1<br />
1.6<br />
emulsion 10(5) 10.25 102.5 2.0 5(10) 4.98 99.6 0.6<br />
Luna soap 10(10) 10.45 104.5 1.8 10(10) 10.14 101.4 0.4<br />
∗ RSD is the relative standard deviation<br />
As a preliminary conclusion;<br />
-although the CLS method is a sufficiently good method for analysis of individual<br />
compounds, the method is failed to determine the proper concentrations of components of<br />
benzoic acid in the laboratory preparations and commercial formulations analyzed. Thus the<br />
method is failed to determine the binary combination of benzoic acid and salicylic acid.<br />
- the CLS method is a sufficiently good method for analysis of individual compounds<br />
(salicylic acid and resorcinol ) and their binary mixtures with a considerably good precision<br />
when applied in the same ranges of calibration domains. The variations and relative<br />
deviations from the mean observed is insignificant. Thus, CLS method is a suitable method<br />
for simultaneous determination of salicylic acid and resorcinol mixture.<br />
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