ItemStandardsAnalytical ResultUSP31BP2005IdentificationColorless,transparenthexagonal or needlelike crystalsComplies with standardMelting point()4144About 4443.3Specific rotation (25)-45°-51°About -50°-50°Limit of Nonvolatile residue (%)Not overrun 0.05 under condition of 1050.01Purity(%)97.099.9Organic volatile impuritiesSolvent-Use dimethyl sulfoxideMeets the requirementChromatographic purityThe peak response due to menthol is not less than 97%Pass TestRelated substancesExamine by gas chromatographyPass TestConclusionAnalytical results conforming tostandard USP31/BP2005