Comparison of UV spectrophotometric and LC methods for the determination of nortriptyline hydrochloride in polysorbate 80 based oil/water (o/w) microemulsions.
A new rapid, reliable and specific UV spectrophotometric method was developed for the determination of nortriptyline hydrochloride formulated into o/w microemulsions. The UV spectra of nortriptyline standard solution in methanol and placebo (microemulsion without nortriptyline) were recorded over the wavelength range 200-600 nm and the spectra for placebo and nortriptyline loaded microemulsion were recorded over the range 260-400 nm in order to determine the overlapping that might appears, and hence to set the wavelength that could be used for the quantitative analysis. This method was validated and compared with a liquid chromatography (LC) procedure used for the quantitative analysis of the drug. Both methods showed excellent precision and accuracy with RSD values of 2.37 and 1.41%, respectively, for the LC method, and values of 1.24 and 2.88%, respectively, for the UV spectrophotometric method. The established linearity range was 10-50 microg ml(-1) (r2 = 0.9985) and 20-60 microg ml(-1) (r2 = 0.9979) for the HPLC and UV spectrophotometric methods respectively. The recoveries of nortriptyline from spiked placebos were > 95% for both methods over the linear range. The methods have been successfully used for determining the nortriptyline content of microemulsions and for evaluating the chemical stability of the drug in nortriptyline-loaded microemulsions.
Moreno
Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, Complutense University of Madrid, Spain. marco@eucmax.sim.ucm.es
Ballesteros
M P
MP
Frutos
P
P
Lastres
J L
JL
Castro
D
D
D000929:Antidepressive Agents, Tricyclic / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004655:Emulsions / Q000737:chemistry*; D009661:Nortriptyline / Q000032:analysis*; D011136:Polysorbates; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*
D000929:Antidepressive Agents, Tricyclic; D004655:Emulsions; D011136:Polysorbates; D009661:Nortriptyline