Evaluation in Cellulose Nanocrystals Effectiveness on Composite Film based Wound Dressing from Poly(vinyl alcohol) and Gum Tragacanth

Biomaterial-based wound dressings were fabricated using cellulose nanocrystals (CNCs) as nano-filler in a polymeric mixture of poly(vinyl alcohol) (PVA) and gum tragacanth (GT) via solution casting. Physical and chemical characteristics of neat PVA, PVA/GT and PVA/GT/CNC films with varying concentrations (2 to 10%) of CNCs were observed. Initial analysis of CNCs showed nanosized particles of 104 nm length and 7 nm width. Scanning electron microscopy (SEM) illustrated cluster formations of CNCs in the polymer matrix. Fourier transform infrared (FTIR) spectrometry was used to confirm the chemical functional groups in the material. The presence of GT and CNCs in the polymer matrix improved water uptake and prolonged stability for 7 days. The CNCs enhanced tensile strength from 54.63 MPa to 80.39MPa. Biological properties of PVA/GT/CNC films were analyzed. Results showed that the dressing material was nontoxic to mouse fibroblast cells L929, while film loaded with betel leaf extract exhibited excellent antibacterial activities against Staphylococcus aureus DMST 8840 and Pseudomonas aeruginosa TISTR 781, indicating that composite film was suitable for application in wound dressing.

Formulation, Physical Characterization and Antioxidant Potential of Silymarin Suspensions and Emulsions

Silymarin, is a therapeutically important flavonoid act as a hepatoprotective agent. However, has a positive effect on metabolism act as a hydrophobic drug but has a very low bioavailability. The aim of the present study was to prepare appropriate formulations of Silymarin in order to enhance its bioavailability. The natural suspending agents like (Xanthan gum, Tragacanth gum, Acacia gum and Iranian gum) were used for the formulation of suspensions, while emulsions were prepared with the combination of surfactant, co-surfactant and oil. The formulations were evaluated for their physical stability, pH, refractive index and conductivity. Among different formulations and suspensions prepared with xanthan gum as a green stabilizing agents were most stable. Emulsions formulated with tween 80 as a surfactant, polyethylene glycol as co-surfactant and olive oil were clear and stable for more than six months. The refractive index, pH and conductivity of the most stable suspension and emulsions were 1.347, 6.9 and 0.18 s/m and 1.43, 6.9, 0.01 s/m respectively. It was concluded that xanthan gum and tween 80 with polyethylene glycol has a good potential to enhance the therapeutic efficiency and stability of silymarin suspension and emulsion.