Summary: | In recent years, there has been an increased emphasis to treat patients with parenteral nutrition (PN) at home in an attempt to reduce costs and improve clinical outcomes. This increased interest in home parenteral nutrition (HPN) has stimulated researchers to investigate potential sources of instability. One of the more unstable groups in PN is micronutrients, which can be divided into two groups: vitamins and trace elements. This thesis investigates the effects of artificial light sources (cool white, warm white and UVA) on the physicoP chemical stability of vitamins. Vitamins were chemically analysed using a novel stability indicating HPLC assay that could quantify five waterPsoluble and three fatPsoluble vitamins simultaneously in one run. Samples were physically analysed by visual analysis, microscope analysis, laser diffraction, pH and osmolality. Initial experiments investigated the physicoPchemical stability of vitamins exposed to artificial light sources over a period of 24 hours. In cool and warm white light there was approximately a 20% loss of riboflavin and 10% loss of retinol. In UVA light there was approximately a 20% loss of retinol. All other analysed vitamins were stable over the time period to these artificial light sources. Further experiments investigated these conditions following 6 days of storage between 2P8 C. These experiments revealed similar results in the three types of artificial light source. v The protective effects of lipid emulsions on retinol were then investigated in containers and administration sets. Samples containing lipid emulsions in syringes and administration sets had a statistically significant increase in retinol stability. Nevertheless, degradation in excess of 10% still occurred in these groups. The protective mechanism of lipid emulsions was primarily though to be a result of light obscuration. However, soybean oil (SBO), a clear liquid, provided unexpected obscuration of UVA light suggesting it may reflect or absorb damaging rays thereby improving retinol stability.
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