This certificate of analysis from Octagon Chemicals Limited summarizes test results for a batch of melatonin. The melatonin is a white powder, slightly soluble in water and soluble in other solvents. Tests were conducted according to USP38 standards and showed the melatonin met limits for identification, purity, heavy metals, and assay. The certificate concludes the melatonin meets USP38 standards.

1. OCTAGON CHEMICALS LIMITED
CERTIFICATE OF ANALYSIS
TEL:0086-13071891945 FAX:0086-0535-6715688
Address: ROOM 5032,NO.9 YANAN ROAD,HANGZHOU,CHINA
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Product name Melatonin (Cas 73-31-4)
Batch No. 20191103 Mfg. date 2019.11.09
Rep. Date 2019.11.11 Exp. date 2022.11.08
Packaging 25kg/Drum Test according to USP38
Test Items Standards Results
Appearance White to off-white crystalline powder White powder
Solubility
Slight soluble in water, soluble in
acetone, ethyl acetate and methanol
conforms
Identification IR/UV/HPLC Conforms
Chloride and sulphate NMT0.02% <0.02%
Related
Substances(HPLC)
Single impurity: NMT0.1%
Total impurities: NMT1.0%%
0.051%
0.35
Loss on drying NMT1.0% 0.08%
Residue on ignition NMT0.1% 0.05%
Heavy metals NMT20ppm <20ppm
Assay
(on dried basis)
98.5%~101.5% 99.54%
Conclusion It meets the requirements of USP38 Standards
Storage Store in a well-closed container at ambient temperature
Prepared by: LI Reviewed by: WEI Released by:Zhang