Chromatographic conditions for the elution of aspartame as
optimized by Arora, Shendurse, Sharma, Wadhwa, and Singh
(2013) was used. However, chromatographic conditions for the
elution of neotame were optimized as following:
Three different mobile phases were chosen for the elution of
neotame viz. 0.09% TFA:water:acetonitrile (70:30, 80:20, 60:40).
0.09% TFA:water:acetonitrile (60:40) gave the best resolution as
compared to the other two mobile phases. Three flow rates (0.6,
0.8 and 1.0 ml/min) of the mobile phase were assayed for the estimation
of neotame. The neotame peak merged with the product
matrix peak at a flow rate of 0.8 and 1.0 ml/min, hence, a flow rate
0.6 ml/min was selected for the analysis. At this flow rate the
retention time increased and better resolution was obtained as
compared to the flow rate of 0.8 and 1.0 ml/min.
In order to select the wavelength for analysis of neotame, a reference
standard solution of neotame was injected and UV spectra
were scanned in the UV range (200–380 nm). Neotame showed
kmax at 210 nm.