and NLT 5.0 between the glutathione and l -phenylalanine peaks Relative standard deviation: NMT 1.5% for replicate injections Analysis Samples: Standard solution and Sample solution Calculate the percentage of any impurity in the portion of Glutathione taken: Result = (r U /r S ) (C S /C U ) 100 r U = = peak response of any peak from the Sample solution other than glutathione r S = = peak response of the glutathione peak from the Standard solution C S = = concentration of USP Glutathione RS in the Standard solution (mg/mL) C U = = concentration of Glutathione in the Sample solution (mg/mL) Acceptance criteria Individual impurity: NMT 1.5% for the impurity with the relative retention time of about 4 Total impurities: NMT 2.0% SPECIFIC TESTS Clarity and Color of Solution Sample solution: 0.1 g/mL in water Analysis: Using identical tubes of colorless, transparent, neutral glass with a flat base and an internal diameter of 1525 mm, compare the liquid to be examined with water, the depth of the layer being 40 mm
10.1001/archsurg.1985.01390320065013 50 KimH
Wahid A, Manek N, Nichols M, Kelly P, Foster C, Webster P, et al
Third-party testing certificates (also called Certificates of Analysis or COAs) should confirm peptide identity and purity, ideally through HPLC and mass spectrometry
Anneren G, Magnusson CGM, Nordvall SL
