In-situ DSC testing analysing hydrolysis dependent lactose glass transitions

Dynamic scanning calorimetry (DSC) is a powerful tool for the analysis of phase transitions and could be a valuable in-situ addition to neutron scattering experiments. An in-situ sample stick has been developed for use on IRIS to allow for DSC measurements to be taken during QENS scans. By running both measurements simultaneously, an accurate determination of phase transition temperature can be made for identical samples during DSC and QENS, whilst temperature adjustments can be made for a QENS scan depending on findings during the in-situ DSC scan. During the commissioning of the in-situ calorimeter, the testing of lactose samples at three varying stages of hydrolysis has been proposed. Lactose is disaccharide that often exists as an amorphous, hygroscopic glass. Upon hydrolysis, lactose undergoes plasticization and produces glucose and galactose. This causes the glass transition temperature, T¬G, to decrease, which impacts the storage of the sugar. The aim of the experiment is to observe any dynamic changes that are associated with the hydrolysis dependent change in TG by running the in-situ DSC simultaneously with QENS measurements. Such observations would provide further insight into the effects of water adsorption on lactose molecules and the change in TG that accompanies this hydrolysis.