Eca 500ii

The UV spectroscopic analyses of Taxol samples were measured at λ 227 nm (RIGOL, Ultra-3000 Series) comparing to authentic Taxol [13 ,30 ,35 ,37 (link)]. Blank media was used as negative baseline for all spectrophotometric analyses.
FT-IR spectrum of the purified Taxol samples was analyzed by JASCO FT-IR 3600 Spectrophotometer. The purified Taxol sample was grinded with KBr pellets, pressed into discs under vacuum, comparing to authentic one. The absorption was measured in the region 500 to 4000 cm⁻¹ [3 ]. The chemical structure of extracted Taxol was confirmed from the H and C NMR spectroscopy (JEOL, ECA-500II, 500 MHz NMR) comparing to authentic Taxol. The samples were dissolved in CDCl₃, chemical shifts are given in ppm (δ-scale) and the coupling constants are expressed in hertz (Hz).

Two liver targeting ligands (GA and LA) were selected in the present study to be conjugated to the developed nanocarrier system. Synthesis of the dual ligands-CS was done using the procedures reported by Chen et al.14 (link) Briefly, 1 g of CS was dissolved in 80 mL of 1% (v/v) acetic acid solution. On the other hand, 0.5 g of the ligand (GA) was dissolved in 50 mL of DMF with 1 g of EDC.HCl and 0.33 g NHS. The activated GA solution was then added to the CS with stirring at room temperature for 72 hrs. The reaction was terminated, and the resulting CS-GA conjugate was collected by addition to acetone followed by filtration. The obtained product (0.85 g) was then dissolved in 32 mL of TEMED/HCl buffer adjusted at pH 4.7. The second ligand, LA (0.95 g) was in turn dissolved in 8 mL of the same buffer and activated by EDC.HCl (0.6 g) and NHS (0.37 g). The two solutions were then mixed and allowed to react at room temperature for 3 days. The pure dual ligands-CS conjugate (DL-CS) was obtained by extensive dialysis for 72 hrs followed by freeze-drying. The preparation of the conjugate was confirmed by FTIR and ¹H-NMR analysis (ECA 500II, JEOL, Japan).