Monitoring thermochemical events and weight loss as a function of temperature can give valuable insight into solid form characteristics, mechanisms of polymorphic transformations, and solid-state degradation pathways. SSCI uses modern DSC/TG instrumentation to analyze these properties of bulk and formulated solid products.
Differential scanning calorimetry (DSC) is one of the most widely used thermal analysis techniques for the characterization of pharmaceutical solids. Thermal events such as melting, recrystallization, decomposition, and glass transitions can be measured. Additionally, quantitative mixture analysis (for example, different polymorphs) can be performed. The use of modulated DSC expands the capabilities of DSC and allows one to measure heat capacities and characterize reversible/non-reversible thermal transitions.
Micro thermal analysis (µTA) is a relatively new technique that combines the resolution of an atomic force microscope (AFM) with thermal conductivity measurements. Analogous to mapping experiments such as IR, Raman, EDX, or TOF-SIMS, µTA can map a two dimensional area and display the spatial position of different materials due to their different thermal conductivity. A distinct advantage of the technique is the ability to acquire AFM images in conjunction with the thermal conductivity map.
Melting point determination is a very important aspect of polymorph analysis. SSCI provides melting point determination as per the various methods outlined in the USP.
Thermogravimetric analysis (TGA) measures the thermally induced weight loss of a sample as a function of temperature. In conjunction with DSC and hot-stage optical microscopy, TGA provides an excellent approach to the determination of thermal properties of the pharmaceutical material. Extending the TGA technique to thermogravimetric/infrared analysis (TG/IR) provides the ability to not only measure the thermally induced weight loss, but also to chemically identify the volatile component during each weight loss step. As a volatile component is evolved from the sample in the TG furnace, it is swept into a gas-phase IR cell for spectroscopic analysis and potential chemical identification. TG/IR is an ideal technique for solvate and hydrate analysis.
Hot-stage optical microscopy is a technique that SSCI uses in conjunction with DSC and TG or TG/IR to characterize the thermal properties of your pharmaceutical solid. SSCI provides analysis with two different hot-stages that allow for controlled temperature experiments from -196 to 600 °C. Visual thermal events (such as melting, recrystallization, or volatilization) can be captured as video or digital images.