## 2 Experimental
### Methods
#### 2.2.5 Characterization of GEF SDs  
Based on the saturation solubility and dissolution test performance out of three SDs, only F1 and F3 were chosen for further characterization. The lyophilized products and the individual excipients were analyzed by differential scanning calorimetry (DCS), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Moreover, the samples were subjected to micrometrics to evaluate their fundamental and derived properties. Differential scanning calorimetry (DSC) was conducted for the physical state analysis of the products by \"DSC-8000 (Perkin Elmer Instruments, Shelton, CT, USA)\". The analysis was conducted under an inert N\({}_{2}\) purging (20 mL/min) at the heating rate of 10 \({}^{\circ}\)C/min in the range of 30-300 \({}^{\circ}\)C temperature. \"The DSC instrument was calibrated with 100% pure Indium (Melting point 156.6 \({}^{\circ}\)C and 6.80 cal/g heat of fusion)\". Around 5 mg of each sample to be tested were crimped in the standard aluminum pans and lid for the analysis, whereas a similar empty pan was put in the reference cell. The thermograms of GEF, excipients, lyophilized solid dispersions and the inclusion complex were recorded and analyzed through the PYRIS V-11 software attached to the instrument. Fourier Transform Infrared (FTIR) Spectroscopy  
The FTIR spectra of GEF-pure, individual excipients, freeze-dried SDs and the inclusion complexes were recorded by using a Perkin Elmer (FTIR). Each material was taken and kept in the sample holder to analyze the spectra across 4000 to 400 cm\({}^{-1}\) wavenumber by 3 scans and 2 cm\({}^{-1}\) resolutions. The IR spectra of pure sample were compared with the IR spectra of prepared formulations to evaluate the changes and shifting in the wavenumbers of the respective functional groups. Nuclear Magnetic Resonance (NMR)  
To assess the structural changes in the GEF after formulation into SDs, the proton NMR (1H NMR) was used. The study was carried out for GEF pure, F1, physical mixture of GEF, TPGS and HP \(\beta\)-CD (PM) and F3 to compare the NMR spectra of each. The samples were assessed by \({}^{1}\)H NMR (functioning at 700 MHz frequency) (Bruker NMR; Switzerland) spectroscopy. Tetramethylsilane (TMS) was used as versatile internal standard, while deuterated dimethyl sulfoxide (DMSO) served as the solvent for this study. Morphology by Scanning Electron Microscopy (SEM)  
The morphology of GEF pure, PM, F1 and F3 was assessed through SEM. The SEM analysis \"(Zeiss EVO LS10, Cambridge, UK)\" was completed using the gold-sputter technique. Herein, the gold coating was completed on the dried samples using the \"Q-150R Sputter Unit\" of \"Quorum Technologies Ltd. (East Sussex, UK)\". The coating was conducted for 1 min at 20 mA current in an argon atmosphere. Finally, the imaging was completed at working distance of 15 mm, accelerating voltage of 10-20 kV and the magnification was 500-2000 times. Micromerities and Flow Property  
The GEF physical mixture and the prepared SDs were evaluated for different parameters of micromerities, such as Carr's index, Hausner ratio and angle of repose [27]. These variables describe the flow behavior of dried granular materials and powdered samples. For the samples having ideal flow properties, the value must be less than 15% for Carr's index and \(<\)1.25 for Hausner ratio. These parameters can be calculated through the tapped and bulk densities of the sample. The angle of repose was determined by the funnel method. The samples were passed from funnel to a flat surface to form a cone, and then the height (h) and radius (r) of the cone were measured. The sample shows the value as excellent flow(\(<\)30\({}^{\circ}\)), good flow (\(<\)31-35\({}^{\circ}\)), fair flow (\(<\)36-40\({}^{\circ}\)) and poor flow (\(<\)41-55\({}^{\circ}\)) [28].