Dsc 1 star system

A differential scanning calorimeter (DSC 1 STAR System, Mettler Toledo, Greifensee, Switzerland) with an intracooler TC100 (Huber, Offenburg, Germany) was used to characterize the scaffolds. The measurements were carried out using ~10 mg of sample in a stainless-steel pan (120 µL). An empty pan was used as a reference. The thermal scanning protocol used was: cooling down from 25 to 0 °C at 40 °C/min, isothermic step at 0 °C for 5 min, and heating to 150 °C at 10 °C/min. The samples were subjected to the same thermal protocol twice. The melting temperature (T_m) and changes in the enthalpy of melting (∆H_m) were determined from the first scan. The glass transition temperature (T_g) was determined in the amorphous material (second scan). The curves were analyzed using the STARe software (DB V 12.10). Prior to the measurements, the melting temperature and enthalpy values were calibrated using indium as standard. All determinations were made in triplicate.

Calorimetric experiments of studied ILs were performed by means of a Mettler Toledo DSC1STAR System equipped with a liquid nitrogen cooling accessory and an HSS8 ceramic sensor (a heat flux sensor with 120 thermocouples). Each sample with a mass of around 10–20 mg was measured in aluminum crucibles with a 40 μL volume. During the experiments, the flow of nitrogen was kept at 60 mL min^–1. Enthalpy and temperature calibrations were performed using indium and zinc standards. Low-temperature verification was made using CCl₄ and n-heptane (182.15 K, 140.5 J g⁻¹) at different scanning rates (0.7, 1, 5, and 10 K min⁻¹). The baseline was constructed as a straight line from the onset to the endpoint. A dedicated software Mettler Toledo DSC1STAR allows various calculations (onset, heat, peak temperature, etc.) from the original recorded DSC curves. Prior to the measurement, the samples were annealed 30 min at 373 K. Temperature ramps involved cooling to 143 K and then heating to 373 K with a rate of 10 K per min. Samples were cycled at least 3 times to ensure reproducibility and high accuracy. The 6-h aging experiment was performed at 183 K after cooling with the rate of 10 K min⁻¹.

The thermal properties of non-incubated samples were investigated by DSC in the Mettler Toledo DSC1 STAR system. The measurements were performed under a nitrogen atmosphere (50 cm³·min⁻¹). The temperature ramp was set from 20 to 200 °C (10 K·min⁻¹), followed by annealing at 200 °C for 5 min, subsequently followed by a cooling scan from 200 to 20 °C (20 K·min⁻¹), then an isothermal step at 0 °C for 5 min, and finally a second heating scan from 0 to 200 °C (10 K·min⁻¹). The melting point temperature (Tm) as well as the heat of fusion (ΔHm) were measured during the first heating cycle.
The degree of crystallinity χc was calculated according to the following equation (Equation (1):
where 〖ΔH〗_m is the heat of fusion and 〖ΔH〗_m^0 is the tabulated heat of fusion for theoretically 100% crystalline Ecoflex homopolymer (115 J g⁻¹) [53 (link)].

Glass transition temperature (T_g) was determined by differential scanning calorimetry (DSC) with a Mettler-Toledo DSC1 Star System under a nitrogen atmosphere. The instrument was calibrated using Indium melting temperature and enthalpy, and corrected for empty cell baseline. About 10–15 mg in mass was extracted from a thin film of each sample by cutting a disk of ~3 mm in diameter and encapsulated into 40 μL Al pan. The experiments were conducted by performing two heating and one cooling ramp, between −20 °C and 160 °C, at 20 °C/min. The T_g values calculated with the midpoint method for each sample are reported in Table 6, while raw DSC curves are in Figures S2 and S3.

The study of FT-IR and DSC was used as a means for studying drug-excipients compatibility. In FT-IR study, KBr pellets were prepared with drug and excipients and scanned under Varian FT-IR in the wavelength region of 4000–400 cm⁻¹. Thermal analysis was performed for drug and mixture of drug with excipients using DSC (Mettler DSC 1 star system, Zurich, Switzerland).