| Lactose is the common disaccharide found in dairy products. It can, however, be a source of discomfort for those whom are lactose intolerant. Therefore, it is necessary to accurately, reliably, and efficiently determine the lactose content of foods. The goal of this research was to develop a reversed-phase HPLC method with UV detection for the determination of lactose. Aminobenzoic acid was used to prepare a derivative, making detection possible in the 300--360 nm region. The stationary phase is a C8 column, with 85% methanol 15% water mixture at pH 5 as the mobile phase. A linear response of peak area to lactose concentration of 0.018 mg/mL to 0.36 mg/mL was obtained with an estimated detection limit of 0.0036 mg/mL lactose concentration. The reproducibility was established with a 4.95% relative standard deviation. The average recovery was 107%, and results were in strong agreement with the standard alkaline ferricyanide method, establishing accuracy. |
