The physical and chemical properties, such as purity, crystal form, stability and safety, must be monitored in the development and production of drugs to ensure that the drugs have the expected properties. As we all know, organic compounds, including drugs, often have a variety of structures and crystal states, which will inevitably affect the processing conditions, period stability, decay and biological delivery ability of drugs. The final composition of the drug contains a variety of active components and the products produced by their interaction, of course, excipients, moisture, tablet coating, etc., which are very complex. So it is more and more important to characterize it comprehensively. One of the most ideal test methods is thermal analysis.
Thermal analysis is characterized by small amount, sensitive and fast method. In a short period of time, it can obtain all kinds of information that need complex technology or long-term research. Differential scanning calorimeter (DSC) is one of the most widely used thermal analyzers in the field of medicine at present. By measuring the changes of enthalpy and temperature of drugs with program temperature control, DSC can study specific information such as:
 drug purity
Study on the polycrystalline, metastable and amorphous forms of drugs
 optimized freeze drying
 lipid detection and protein denaturation

1. drug purity
One of the most important applications of DSC in drug analysis is to evaluate drug purity. Since the commercial DSC products appeared in 1960s, it has been widely accepted because of its rapid, accurate and easy operation. The measurement of response time and temperature of DSC cell is very important for the accurate analysis of purity. The power compensation DSC has a small furnace body
(& lt; 1g), the response time is very fast, and its use of platinum resistance temperature measurement accuracy is high, accurate, so it is very suitable for the accurate measurement of purity. As we all know, when there are trace impurities in the material, its melting point will be reduced and its melting range will be widened.