Detection of ultrafiltration membrane rejection rate of spectrophotometer
Key words: spectrophotometer; ultrafiltration membrane rejection; US analysis ; UV-15001. Main reagents and materials: distilled water or buffalo serum albumin of equivalent purity (molecular weight 67000) 2. Main equipment: UV Spectrophotometer, vacuum drying oven, analytical balance 1000ml volumetric flask, 10ml volumetric flask 5, straw, 1000ml, 2000ml beaker each 3. Standard solution configuration: bovine serum albumin vacuum drying at 105 ° C to Constant weight, accurately weighed 1.00g of bovine serum albumin in a 1000ml volumetric flask, and separately took bovine serum albumin solution 0.2, 0.4, 0.6, 0.8, 1.0ml into a 10ml volumetric flask and dilute to the mark with distilled water to configure the concentration. It is a 20, 40, 60, 80, 100 mg/l bovine serum albumin standard solution. 4. Preparation of the standard curve: The protein has the maximum absorption of ultraviolet light at 280 nm, and the absorption value of the protein solution at 280 nm is proportional to its concentration. The standard solution was measured at a wavelength of 280 nm using a 1 cm cuvette on an ultraviolet spectrophotometer, and the distilled water was blank. The standard curve is prepared by taking the protein concentration as the abscissa and the optical density as the ordinate drawing. (T is %, A = lg1/T) 5. Test of sample: The protein was placed in a protein solution having a concentration of 1000 mg/l, and it was used as a solution for evaluating the performance of the ultrafiltration membrane. 6. Evaluation of ultrafiltration membrane: The prepared sample solution was run through an ultrafiltration membrane at 0.1 MPa and normal temperature, and the ultrafiltrate was collected after 20 minutes. The optical density of the original solution and the ultrafiltrate was measured in the ultraviolet region of 280 nm, respectively. The corresponding concentration was found from the standard curve. 7. Calculation of rejection rate: Interception rate = (1-C 1 /C 2 ) × 100%, where C 1 is the concentration of the ultrafiltrate and C 2 is the concentration of the stock solution. 8. Test results: Two samples were taken at the same time for parallel testing, and the arithmetic mean of the test values ​​was used as the test result. Key words: spectrophotometer; ultrafiltration membrane rejection; US analysis ; UV-1500
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