## 4 Results and Discussion
The BjH adsorption cumulative surface area of pores, BjH desorption cumulative surface area of pores, BjH adsorption cumulative volume of pores, BjH desorption cumulative volume of pores, DH adsorption cumulative surface area of pores and D-H desorption cumulative surface area of pores between 1.7000 nm and 300.0000 nm for Bup/PVP/PVA nanofibers were 20.344 m\({}^{2}\)/g, 12.2997 m\({}^{2}\)/g, 0.031125 cm\({}^{3}\)/g, 0.027263 cm\({}^{3}\)/g, 5.159 m\({}^{2}\)/g and 10.1739 m\({}^{2}\)/g, respectively. The single point adsorption and desorption total pore volume of pores less than 40.4123 nm width at p/p\({}^{\circ}\) = 0.95000000 were 0.017185 cm\({}^{3}\)/g and 0.01695 cm\({}^{3}\)/g respectively. Analysis of Bup/PVP/PVA nanofibers by BET showed Adsorption and desorption average pore diameter \(-1126.44019\) nm and \(-1111.64244\) nm. BjH adsorption and desorption average pore width were 6.1196 nm and 8.8663 nm respectively. D-H adsorption and desorption average pore width of Bup/PVP/PVA nanofibers were 15.7863 nm and 9.7551 nm, respectively. The BET analysis of cross linked-Bup/PVP/PVA nanofibers showed the BET surface area and langmuir surface area in the amount of 2.3263 m\({}^{2}\)/g and \(-13.8391\) m\({}^{2}\)/g m\({}^{2}\)/g, respectively. The BjH adsorption cumulative surface area of pores, BjH desorption cumulative surface area of pores, BjH adsorption cumulative volume of pores, DJH adsorption cumulative volume of pores, DJH adsorption cumulative surface area of pores and D-H desorption cumulative surface area of pores between 1.7000 nm and 300.0000 nm for cross linked-Bup/PVP/PVA nanofibers were 55.229 m\({}^{2}\)/g, 39.9707 m\({}^{2}\)/g, 0.089977 cm\({}^{3}\)/g, 0.083155 cm\({}^{3}\)/g, 23.467 m\({}^{2}\)/g and 33.1356 m\({}^{2}\)/g respectively. The single point adsorption and desorption total pore  
Figure 2:3 Atomic force microscopy (AFM) topography image of glutaraldehyde (GTA) cross-linked Bup/PVP/PVA nanofiber mats. volume of cross linked-Bup/PVP/PVA nanofibers pores less than 40.4123 nm width at p/p\({}^{\circ}\) = 0.950000000 were 0.053327 cm\({}^{3}\)/g and 0.051009 cm\({}^{3}\)/g, respectively. Analysis of cross linked-Bup/PVP/PVA nanofibers by BET showed adsorption and desorption average pore diameter 91.69515 nm and 87.70968 nm. BJH adsorption and desorption average pore width were 6.5166 nm and 8.3216 nm respectively. D-H adsorption and desorption average pore width were 11.2115 nm and 9.0938 nm, respectively. The mechanical properties of electrospun Bup/PVP/PVA nanofibers mat was examined and was shown in Figure 2:4 As can be seen, the tensile stress of the Bup/PVP/PVA nanofiber mat was 1.48 \(\pm\) 0.089 Mpa with modulus of 48.88 \(\pm\) 52.184 Mpa and 31.43 \(\pm\) 1.34% for tensile strain. To evaluate drug-release properties, the in vitro dissolution measurements of Bup-loaded nanofiber mats were performed using the dissolution device (900 mL phosphate buffered saline, 100 rpm, 37 \({}^{\circ}\)C), and the Bup concentration in the samples was assayed by the HPLC method. The Bup standard solutions of 2, 5, 10, 15, 20, 25, 30 ppm were prepared. Standard solutions were injected into HPLC system and chromatograms were recorded at the wavelength of 288 nm. The peak area ratios of the standard peak area and internal standard peak area were calculated and the calibration curve was drawn as the plot of peak area versus concentration (Figure 10). Figure 11 shows the release profile of the prepared drug-loaded electrospun mats. The release percentage of the drug was calculated based on the maximum drug release (25 mg in 8 \(\times\) 8 cm piece of the mat). The in vitro Bup release started 5 min after immersion for Bup/PVP nanofibers mats. The maximum drug release was reached in the first 24 h (45%  
Figure 2:5 Calibration curve of Bup standard solutions in PBS. Figure 2:6 Mechanical properties of Bup/PVP/PVA nanofibers. drug release in the first 1.5 h after the immersion and 50% in 24 h), which can be attributed to the burst release properties of PVP nanofibers [24, 25].