## 3 Results and Discussion
### Budesonide Inclusion in Cyclodextrin Complexes  
In a subsequent stage, different amounts of BUD were entrapped in CD complexes with the optimum ratio, H\({}_{2}\)O/ EtOH 80/20. BUD was entrapped in 5 wt%, 10 wt%, 20 wt%, and 30 wt% forming the samples CD-BUD 5 wt%, CD-BUD 10 wt%, CD-BUD 20%wt, and CD-BUD 30 wt%. FTIR measurements were performed for the evaluation of the ionic interactions between BUD and CD (Figure 7). In the FTIR spectra of the CD-BUD inclusion complexes, characteristic peaks of CD and BUD are present. Moreover, it is evident that by increasing the amount of the added BUD in the complexes, the peaks present in the regions 1565-1760 cm\({}^{-1}\) and 2850-3000 cm\({}^{-1}\) attributed to the drug are intensified [30]. In a subsequent level, the degree of crystallinity of the samples was calculated from the XRD spectra of Figure 8. The results in Table 2, as well as in Figure 8, reveal that by increasing the drug content, the peak intensities along with the degree of crystallinity increasing as a result, which is in accordance with previous data from our group when BUD was entrapped in chitosan nanoparticles [8]. Figure 8: X-ray diffractograms of CD–BUD 5 wt%, 10 wt%, 20 wt% and 30 wt%. Figure 7: FTIR spectra of BUD, CD and CD–BUD 5 wt%, 10 wt%, 20 wt% and 30 wt%. The inclusion complexes were observed through SEM images, as shown in Figure 8, and their morphological characterizations remained unaffected. Neat BUD is a crystalline compound with columnar crystalline smooth surfaced rods; [31] whereas, the inclusion complexes in Figure 9 are depicted as irregular spherical shaped agglomerated particles. The XRD results established that by increasing the BUD content, the degree of crystallinity rises. Consequently, unentrapped crystalline rods were expected to be present in SEM images. However, the morphological image of the samples for the various BUD concentrations is similar. DSC analysis confirms the aforementioned statement. The DSC thermograms of neat BUD and CD-BUD samples are presented in Figure 10a,b, respectively. Neat BUD has a melting peak at 257 \({}^{\circ}\)C [32] and a prior exothermic peak at 233 \({}^{\circ}\)C. The exothermic peak is attributed to the energy produced during the transition of BUD's less stable crystals to a more stable crystal phase (exothermic process). Further heating leads to the melting point [33]. DSC curves of the CD-BUD samples indicate that when forming inclusion complexes with CD, BUD is entrapped in the internal cavity in the amorphous phase [34]. The melting point of BUD is diminished and shifted to lower temperatures. Moreover, the presence of melting peaks at CD-BUD complexes is attributed to the non-included amount of BUD while the melting point shifting to 218-225 \({}^{\circ}\)C is ascribed to the interactions of BUD with CD. \begin{table}
\begin{tabular}{c c} \hline \hline
**Sample** & **Degree of Crystallinity (\%)** \\ \hline CD–BUD-5\% & 43.9 \\ CD–BUD-10\% & 45.4 \\ CD–BUD-20\% & 53.6 \\ CD–BUD-30\% & 56.6 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Degree of crystallinity of BUD, CD and CD–BUD 5 wt%, 10 wt%, 20 wt% and 30 wt%. Figure 9: SEM images of (**a**) CD–BUD 5% (**b**) CD–BUD 10% (**c**) CD–BUD 20% (**d**) CD–BUD 30%. Furthermore, the thermal stability of the inclusion complexes was evaluated through TGA measurements (Figure 11). Neat BUD demonstrates a one-step mass loss between 250-370 \({}^{\circ}\)C, while at 600 \({}^{\circ}\)C the mass residue is at about 5%. In contrast, neat CD has two main decomposition steps. The first is at 50-100 \({}^{\circ}\)C and is attributed to the samples' moisture, while during the second step at 317 \({}^{\circ}\)C, the degradation of the oligosaccharidesanitiates [35]. The inclusion complexes reveal a comparable to neat CD degradation profile, with two decomposition steps.