• DARIUSH SEMNANI

Articles written in Bulletin of Materials Science

• Electrospun polyvinylidene pyrolidone/gelatin membrane impregnated with silver sulfadiazine as wound dressing for burn treatment

Nanofibrous membranes used for burn treatment have become widely popular due to their large surface area and high porous structure. In this study, electrospinning was used to fabricate a blended nanofibrous membrane of polyvinylidene pyrolidone (PVP) and gelatin, to use as wound dressing. The physical and mechanical properties of this novel membrane were investigated using SEM, FTIR and tensile tests. Results showed that poor mechanical properties of gelatin, which are preferred in medical applications for curing burns as they allow for antigen activity and skin repair, can be enhanced byadding PVP in the solution. Silver sulfadiazine (AgSD), an antibacterial agent, was also impregnated into the PVP/gelatin nanofibrous structure during electrospinning. The membrane thus fabricated showed antibacterial activities against both the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. AgSD release behaviour of fabricated samplesindicated short-term drug delivery. Itwas concluded that the proposed drug-loaded membrane can be used aswound dressing, specifically, in treating skin burns.

• Systematic investigation of parameters of an electrospinning process of poly(acrylic acid) nanofibres using response surface methodology

In this study, response surface methodology (RSM) based on the central composite design (CCD) was used for modelling the electrospinning process of polyacrylic acid (PAA) nanofibres, so as to assess simultaneously the effect ofthe most important electrospinning parameters (concentration of polymer solution, applied voltage, distance between the nozzle and collector and flow rate of solution) on the diameter of electrospun PAA nanofibres. The surface morphology was studied by scanning electron microscopy (SEM). The average diameter of PAA nanofibres obtained was from 233 to 1210 nm from SEM images with different process parameters. The results showed that the solution concentration, the applied voltage and the distance between the nozzle and collector are, in that order, the most important parameters affectingthe diameter of nanofibres. The flow rate, however, showed no significant effect on the nanofiber diameter. The RSM model predicted that under optimal electrospinning conditions (solution concentration of 3 w/v%, voltage of 16 kV, electrospinning distance of 15 cm and flow rate of 1.75 ml h$^{−1}$), the nanofibres would be 262 nm in diameter, which was proved to be veryclose to the actual measured value. Therefore, the obtained results demonstrated the good performance of the RSM model in investigating the effect of electrospinning variables and predicting the diameter of PAA nanofibres. PAA nanofibres have great potential in applications such as sensors and biosensors, removal of heavy metals and contaminants, muscle tissue engineering, etc. and the use of thinner nanofibres leads to their improved performance in these applications.

• Comparison of the antifungal activity of fluconazoleand ketoconazole-loaded PCL/PVP nanofibrous mat

In this study, the antifungal activity of both fluconazole and ketoconazole was compared. The drugs were loaded into the polycaprolactone (PCL)/polyvinylpyrrolidone (PVP) nanofibrous mats and the effect of the drug-loaded samples on Candida albicans (Ca) were investigated by disc diffusion method. Furthermore, the characterization of nanofibrous mats was performed by field emission scanning electron microscopy, Fourier transform infrared (FT-IR) and contact angle tests. The mean diameter of nanofibres was 656 nm and it decreased with the addition of drugs into the electrospinning solutions, because the viscosity of solutions were decreased while electron conductivity of solutions was increased. With increase in the amount of the drug from 5 to 15%, the hydrophilicity increased. FT-IR revealed both drugs were physically embedded in the nanofibres and confirmed their presence in the composition. In addition, the degradation behaviour of samples was significant due to by the amount and the dissolution of PVP and approximately 40% loss weight occurred after 22 days. In the disc diffusion tests, both drug-loaded samples had antifungal effect on sensitive isolates of Ca, while for resistant of isolate the ketoconazole had more effective than fluconazole. Overall, the study highlights the ability of antifungal drug-loaded PVP/PCL nanofibrous mats as potential wound dressing materials and local delivery systems.

• # Bulletin of Materials Science

Volume 45, 2022
All articles
Continuous Article Publishing mode

• # Dr Shanti Swarup Bhatnagar for Science and Technology

Posted on October 12, 2020

Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020