Importance of the Melting Point of Urea
Pharmaceutical-grade urea is used as an active pharmaceutical ingredient (API) in topical dermatological applications to promote wound healing and skin rehydration, and to treat skin conditions such as eczema or psoriasis. Producers of API-grade urea and of topical creams are required to verify the identity and purity of urea at quality control, quality assurance, or incoming goods inspection according to strict regulations set by the international or national Pharmacopeia (e.g. European (Ph.Eur.), United States (USP), etc.).
Purity and Identity Verification of Urea
To verify the identity and purity of a crystalline substance, the pharmacopeia monograph requires a check of its melting point. Visually, this is observed as the point at which the last crystal of the substance melts. A pure substance has a sharp melting point, whereas an impure substance melts over a wide temperature range lower than the melting point of the pure substance (known as melting point depression).
With this application note you will learn to determine the melting point of urea according to regulations set by Pharmacopeia using the METTLER TOLEDO Melting Point Excellence.