Browsing by Author "Iyambula, Aina K"

Now showing 1 - 1 of 1
  • Thumbnail Image
    Item
    Development of a “greener” hplc-uv method for the analysis of reducing sugars in apple juice and indigenous fruits using acetone as an alternative solvent
    (University of Namibia, 2023) Iyambula, Aina K
    Chromatographic techniques can be made more environmentally friendly, i.e., “greener”, by a number of different strategies. One approach is to replace the toxic mobile phase solvents such as acetonitrile with greener alternatives. Acetone, in particular, has proven to be a suitable alternative to acetonitrile, since the two solvents have similar physicochemical properties, including solubility, miscibility and viscosity properties. However, due to acetone’s high ultraviolet (UV) cut–off wavelength (330 nm), it normally cannot be used as a mobile phase solvent when performing high performance liquid chromatography (HPLC) analysis with UV detection. In this study, a reversed-phase HPLC–UV method using acetone-containing mobile phase was developed for the determination of reducing sugars in apple juice and two indigenous fruits, Berchemia discolor and Hyphaene petersiana. Pre-column derivatisation of analytes via reductive amination with p-aminobenzoic acid ethyl ester (ABEE) was performed to enable photometric detection at 307 nm. The method was directly compared to a method that utilised acetonitrile-containing mobile phase. Although the detection wavelength of the ABEE derivatives is below the UV cut–off wavelength of acetone, it is high enough above acetone’s absorbance maximum (~280 nm) to enable satisfactory detection of the derivatives. Hence, the method compared well with the acetonitrile method, providing similar resolution and selectivity, as well as sufficient sensitivity to facilitate the quantitation of glucose and fructose in all the fruits and juice investigated in this study. Although the method was only validated in terms of precision, linearity, limit of detection and quantitation but no other aspects such as accuracy, it shows potential to be used as a greener alternative for sugar analysis for laboratories that only have access to HPLC–UV instruments