The objective of this study was to prepare and characterize physically crosslinked gel formulations of chitosan (CS)-graft-poly(N-isopropyl acrylamide) (PNIPAAm) and polyvinyl alcohol (PVA) for smart delivery of an antifungal drug, Voriconazole, for mucosal applications. For this purpose, cryogels of CS-g-PNIPAAm/PVA and CS/PVA were tested by means of texture profile analysis and rheology to determine optimal matrix properties for topical application. The ratio of 75/25 v/v % CS-g-PNIPAAm/PVA was selected to be used for formulation since it gave low compressibility and hardness (1.2 and 0.6 N) as well as high adhesion properties and non-Newtonian flow behavior. The cryogels and formulations were further characterized by means of FTIR spectroscopy, swelling behavior, texture analysis, scanning electron microscopy (SEM), thermal (differential scanning calorimetry (DSC) and TGA), and rheological behavior. The drug loading capacity and in vitro release profile of the drug, storage stability, and cytotoxicity tests were also performed for the gel formulation. The FTIR, DSC, and TGA results verified the successful formation of cryogels. Swelling studies revealed a pH-dependent swelling ability with a maximum swelling degree of 1200% in acid and 990% in phosphate buffer (pH = 7.4). Thermal studies showed that CS-g-PNIPAAm/PVA 75/25 had higher thermal stability proving the structural complexity of the polymer. The loading capacity of Voriconazole was found to be 70% (w/w). The in vitro release profiles of Voriconazole showed Fickian release behavior for CS-g-PNIPAAm/PVA 75/25 gel with an approximate delivery of 38% within 8 h, slower than matrices containing unmodified chitosan. The storage stability test exhibited that the gel formulation was still stable even after aging for two months. Moreover, the cell culture assays revealed a non-toxic character of the polymeric matrix. Overall results showed that the CS-g-PNIPAAm/PVA 75/25 hydrogel has the potential to be used as a smart polymeric vehicle for topical applications.

Poly(vinyl alcohol)/hyaluronic acid cryogels loaded with methotrexate were studied. The physical-chemical characterization of cryogels was performed by FT-IR spectroscopy, scanning electron microscopy, differential scanning calorimetry and dynamic mechanical thermal analysis. Acute toxicity and haematological parameters were determined by "in vivo" tests. The biocompatibility tests proved that the obtained cryogels showed significantly decreased toxicity and are biocompatible. The pH-responsiveness of the swelling behaviour and of the methotrexate release from the poly(vinyl alcohol)/hyaluronic acid (PVA/HA) cryogels were studied in a pH interval of 2-7.4. A significant change in properties was found at pH 5.5 specific for treatment of affected skin in psoriasis disease.

Biopolymers have gained significant attention as a class of polymer materials with a wide range of applications, especially in the medical and pharmaceutical field. Due to particular characteristics, such as biocompatibility, biodegradability, non-toxicity, and functionality, they have become promising candidates for various surgical applications, including as bioadhesives, sealants, wound dressings, sutures, drug carriers, coating materials, etc. Recent research shows that further modification of biopolymers by advanced techniques can improve their functionality i.e., antibacterial activity, cell viability, drug-releasing capability, good wet adhesion performance, and good mechanical properties. This mini review aims to provide a brief report on the type of biopolymers and recent developments regarding their use in various surgical applications.

Although nitrofurans are supposed to be absent in foods, they are still used in veterinary medicine for the treatment of infections in animals not bred for consumption. That meant that there are still samples of honey contaminated with residues of nitrofurans because of bees treated with those pharmaceutical substances. Developing accessible methods to detect them is of high interest to food residue monitoring and regulation programs. We propose an immunochemical method as an alternative to detect four toxic metabolites of nitrofurans (1-aminoimidazolidine-2,4-dione, 3-amino-5-morpholinomethyl-2-oxazolidinone, 3-amino-2-oxazolidone and semicarbazide) in honey. The new method has been optimized and validate for the simultaneous determination of the four metabolites of the nitrofurans honey using biochip technology, and it has been used for the quantitative determination of the residues in 16 Romanian honey samples. The evaluated validation parameters included: linearity, sensitivity (IC50 �2.32 mg/kg), specificity and selectivity, precision (intermediate and reproducibility) and accuracy, decision limit (CCa between 0.37 and 1.05 mg/kg), detection capability (CCb between 0.42 and 1.14 mg/kg), and recovery coefficient (64�192%).

A fast and robust RP-HPLC isocratic method was developed for determination of piroxicam in bulk materials and pharmaceutical formulations. Optimum separation of piroxicam and stress induced degradation a product was achieved using a SB-C18 Eclipse column (150x4.6; 5�m). The mobile phase was a mixture of water: acetonitrile (50:50) with a flow rate of 0.5mL/min. The UV detection was performed at 360nm. The method was validated in accordance with the current ICH guidelines in terms of linearity, limit of detection, limit of quantification, precision, accuracy, recovery and system suitability. The retention time for piroxicam was 2.55 min. The calibration graph was linear in the concentration range 5-90�g/mL. The assay proved to be sensitive, specific and reproducible. The method was applied for the determination of piroxicam in tablets.