spectrometer data.xlsx

The effect of syringe pump pressure fluctuations on the separation efficiency has been characterized using spectrophotometry. A spectrophotometer (Jenway 7315) was used to measure absorbance from 198 to 1000nm wavelengths. The limit of the equipment photometric absorbance is -0.300 to 2.500. To be able to measure in this range, collected milk samples were diluted to 1:250 in PBS before measurement in microcuvette (centre H 15 mm, Brand Gmbh + Co KG) cuvettes. Milk fat was previously reported to absorb strongly at 220 nm in the ultraviolet (UV) range whereas in the Near-infrared (NIR) spectrum milk fat was previously reported to provide a peak at 968 nm. However, absorbance values at 968 nm are very small compared to the 220 nm value because the water content present in milk interferes in this region and strongly absorbs the IR light. Absorbance peaks at both 220 nm and 968 nm were measured from the sample collected from inlet and both outlet sample after 1:250 dilution with PBS solution.