## 3 Results and Discussion
### Drug-Polymer Interaction  
The physicochemical properties of the three polymers and the QPhNO\({}_{2}\) molecule can be used to understand how QPhNO\({}_{2}\) interacts with the three polymers, PMMA, PCL, and PLGA, which can encapsulate molecules. Thus, the interactions between QPhNO\({}_{2}\) and the polymers were studied to identify the most suitable candidate for nanoencapsulation. Figure 9 displays the results obtained. In docking interactions, QPhNO\({}_{2}\) was configured as a flexible ligand in such a way that it could adopt conformations that minimize the inter  
Figure 7: Experimental FTIR spectra of PMMA, PCL, PLGA (as received), and QPhNO\({}_{2}\). action energy in each case. This observation is particularly reasonable when considering the hardness values presented in Table 2: QPhNO\({}_{2}\) < PCL < PLGA < PMMA. The respective binding energies found are PMMA/QphNO\({}_{2}\): \(-4.60691\) kcal/mol, PCL/QPhNO\({}_{2}\): \(-4.43676\) kcal/mol, and PLGA/QPhNO\({}_{2}\): \(-1.81392\) kcal/mol, indicating weak interactions in comparison with other molecular systems (especially the PLGA/QPhNO\({}_{2}\) interactions), such as the protein interactions, with a ligand, which easily varies between \(-10\) to around \(-150\) kcal/mol. \begin{table}
\begin{tabular}{c c c c} \hline
**Molecule** & \(\mathbf{H}^{\circ}\) & \(\mathbf{C_{v}}\) & \(\mathbf{S}^{\circ}\) \\ \hline PMMA & \(-345.65\) au & \(88.41\) J/mol & \(347.03\) J/mol \\ PCL & \(-464.71\) au & \(132.08\) J/mol & \(417.24\) J/mol \\ PLGA & \(-571.32\) au & \(115.97\) J/mol & \(393.56\) J/mol \\ QPhNO\({}_{2}\) & \(-1241.529\) au & \(250.30\) J/mol & \(548.43\) J/mol \\ \hline \end{tabular}
\end{table} 
Table 4: Thermodynamic parameters at room temperature of PMMA, PCL, PLGA, and QPhNO\({}_{2}\) molecules. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Molecules**} & \multirow{2}{*}{**Main Peaks**} & **Freq. Vibrations** & **Freq. Vibrations** \\  & & **Theoretical** & **Experimental** \\ \hline \multirow{6}{*}{PMMA} & (CH\({}_{3}\)) Symmetrical stretch & \(3177\) & \(2981\) \\ \cline{2-4}  & (CH\({}_{3}\)) Symmetrical stretch & \(3058\) & \(2885\) \\ \cline{2-4}  & (C=O) Symmetrical stretch & \(1797\) & \(1726\) \\ \cline{2-4}  & (C, H) Scissors (angular folding) & \(1526\) & \(1145\) \\ \cline{2-4}  & (C-O) Asymmetric Stretch & \(1360\) & - \\ \hline \multirow{6}{*}{PCL} & (C-H) Asymmetric elongation & \(3105\) & \(2947\) \\ \cline{2-4}  & Asymmetric elongation & \(3009\) & \(2873\) \\ \cline{2-4}  & Asymmetric elongation & \(1824\) & \(1724\) \\ \cline{2-4}  & Scissors (fold) & \(1337,1275\) & \(1242,1170\) \\ \cline{2-4}  & (C-O-C) Asymmetric elongation & \(1206\) & \(1049\) \\ \hline \multirow{6}{*}{PLGA} & (C-H) Symmetrical elongation & \(3682\) & \(3649\) \\ \cline{2-4}  & (C-H) Symmetrical elongation & \(3158\) & \(3087\) \\ \cline{2-4}  & (CH\({}_{3}\)) Symmetrical elongation & \(3075\) & \(3020\) \\ \cline{2-4}  & (C-H) Asymmetric elongation & \(3000\) & \(2999\) \\ \cline{2-4}  & (O-C-O) Asymmetric elongation & \(1865\) & \(1753\) \\ \cline{2-4}  & Balance sheet & \(1265\) & \(1087\) \\ \cline{2-4}  & (O-H) Balance sheet & \(594\) & \(698\) \\ \hline \multirow{6}{*}{QPhNO\({}_{2}\)} & (N-H) Asymmetric elongation & \(3432\) & \(3346\) \\ \cline{2-4}  & (C-C) Asymmetric elongation & \(1743\) & \(1649\) \\ \cline{1-1} \cline{2-4}  & (C-H) Scissors (fold) & \(1669\) & \(1537\) \\ \cline{1-1} \cline{2-4}  & (C-H) Balance sheet & \(1561\) & \(1352\) \\ \cline{1-1} \cline{2-4}  & (C-C-C) Asymmetric elongation & \(1332\) & \(1083\) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: The frequencies (in cm\({}^{-1}\)) of the main vibrational modes calculated by the DFT/B3 LYP methods using the base set 6-\(311++\)G and experimental PMMA, PCL, PLGA, and the drug QPhNO\({}_{2}\).