SERS determination and multivariate classification of antibiotics in chicken meat using gold nanoparticle-decorated electrospun PVA nanofibers.

The fabrication of SERS substrate by gold nanoparticle-decorated polyvinyl alcohol electrospun nanofibers which has been used to detect trace sensing of two widely used poultry antibiotics doxycycline hydrochloride and enrofloxacin is demonstrated. The performance of the backscattered Raman signals from the proposed SERS substrate has been initially evaluated with two standard Raman active compounds namely malachite green and rhodamine-6G. The limit of detection of the proposed substrate is estimated to be 7.32 nM. Following this, the usability of the proposed SERS substrate has been demonstrated through the detection of the aforementioned antibiotics in chicken meat samples. The presence of antibiotics in chicken meat sample has been validated with the standard analytical tool of liquid chromatography-mass spectrometry and the results were compared with the proposed sensing technique. Further, principal component analysis has been performed to classify the antibiotics that are present in the field-collected meat samples.

Surface modification of electrospun silk/AMOX/PVA nanofibers by dielectric barrier discharge plasma: physiochemical properties, drug delivery and in-vitro biocompatibility.

The naturally obtained protein Bombyxmori silk is a biocompatible polymer with excellent mechanical properties and have the potential in controlled drug delivery applications. In this work, we have demonstrated dielectric barrier discharge (DBD) oxygen (O2) plasma surface modified electrospun Bombyxmori silk/Amoxicillin hydrochloride trihydrate (AMOX)/polyvinyl alcohol (PVA) nanofibers for drug release applications with controlled plasma treatment duration (1-10 min). The findings indicate that plasma treated electrospun nanofibers for 1-3 min exhibited significant enhancement in tensile strength, Young's modulus, wettability and surface energy. The plasma treated electrospun nanofibers for 1-5 min showed remarkable increase in AMOX released rate, whereas the electrospun nanofibers treated with plasma irradiation beyond 5 min showed only marginal increase. Moreover, the plasma treated nanofibers also exhibited good antibacterial activity against both E. coli (gram negative) and S. aureus (gram positive) bacteria. The untreated and the plasma treated silk/AMOX/PVA electrospun nanofibers for 1-3 min showed enhanced viability of primary adipose derived mesenchymal stem cells (ADMSCs) growth on them and much less hemolysis activity (< 5%). The in vitro biocompatibility of various electrospun nanofibers were further corroborated by live/dead imaging and cytoskeletal architecture assessment demonstrating enhanced cell adhesion and spreading on the plasma treated nanofibers for 1-3 min. The findings of the present study suggest that the silk/AMOX/PVA electrospun nanofibers with plasma treatment (1-3 min) due to their enhanced drug release ability and biocompatibility can be used as potential wound dressing applications.

Chitosan coated silk fibroin surface modified by atmospheric dielectric-barrier discharge (DBD) plasma: a mechanically robust drug release system.

The current study is designed to develop mechanically strong chitosan (Cs) coated silk based drug delivery system loaded with amoxicillin trihydrate (AMOX). For this purpose, surface modification of Antherarea assama silk fibroin (AASF) yarn is carried out using dielectric barrier discharge (DBD) oxygen (O2) plasma at atmospheric pressure followed by coating with drug incorporated Cs (AASF/O2/Cs-AMOX). It is observed that O2 plasma treatment results in altering surface chemistry and morphology of silk fibroin surface which subsequently improves mechanical properties of AASF/O2/Cs-AMOX yarn. The AASF/O2/Cs-AMOX yarn exhibits strong antibacterial activities against gram-positive Staphylococcus aureus and gram-negative Escherichia coli bacteria. In vitro drug release profile reveals biphasic release behavior of AASF/O2/Cs-AMOX yarn consisting of immediate followed by controlled and sustained release of AMOX up to the observation period of 168 hours. MTT cell viability study further reveals that O2 plasma treatment and incorporation of AMOX do not have any adverse effect on cytocompatibility of AASF/O2/Cs-AMOX yarn. Together, all these results suggest that AASF/O2/Cs-AMOX yarn can be explored in treatment of bacterial infected wounds as potential surgical suture.