7.1. Preformulation studies
7.1.1. Identification of pure drug by FTIR
Figure7.1: Identification of Sample through FTIR Figure 7.2: FTIR Spectrum of Standard Prazosin hydrochloride (with references of B.P.- 2009) Table: 7.1 - Characteristics peaks of Prazosin hydrochloride
S.No. Reference peaks (cm-1) Theoretical peak of Prazosin hydrochloride Obtained peaks (cm-1) Functional Group Stretching/
Bending
1 1750-1680 1529.92 1529.92 C=O Stretching
2. 1650-1580 1651.70 1651.70 N-H Bending
3. 1335-1250 1385.08 1385.08 C-N Stretching
4. 1320-1000 1146.18 1146.18 C-O Stretching
5. 900-800 884.13 884.13 C-C Stretching
The comparison between the peak of two graph shows that the characteristic peak of Prazosin hydrochloride …show more content…
No. Wave number cm-1 Peaks of drug(cm-1) Functional Group Stretching/Bending
1. 1651.55 1651.67 C=O Stretching
2. 1416.96 1416.98 C=C Stretching
3. 1072.39 1072.37 C-O Stretching
Figure 7.4: FTIR spectra of Prazosin + HPMC
7.2.2. Preparation of Calibration curve of prazosin hydrochloride
Determination of λ max of prazosin hydrochloride
Exhibited peak absorbance at 330nm (λ max) in methanol.
Standard solution
50mg of standard drug was accurately weighed and placed in 250ml of volumetric flask and 50 ml methanol was added to it and shakes for few minutes to prepare 1000microgram/ml. Stock solution
From this solution the stock solution was prepared by taking 1 ml from standard solution and made the volume to 100 by ethanol and then prepare the solution of 0-10 µg/ml and check the absorbance at 330 nm in UV spectrum. Absorbance v/s concentration were plotted to obtain the calibration graph. The drugs obeyed beer’s law with the above concentration range with ‘r’ value of 0.997 for prazosin and line of equation:-
Figure 7.5: UV Spectrum of prazosin