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Aim: This paper aims to study in-vitro and in-vivo evaluation of chitosan (CHI) biocomposite of gentamicin nanoparticles (GNPs) for wound healing. Methods: In this study, CHI nanoparticles (NPs) were prepared using the ionic gelation technique. GNP biocomposites were examined on the excision wound model in Wistar rats to determine the in-vivo efficiency. Results: The diameter and zeta potential of NPs were between 151–212.9 nm and 37.2 − 51.1 mV, respectively. The entrapment efficiency was in an acceptable range of 36.6–42.7% w/w. The release test information was fitted to mathematical models (Zero, First order, Higuchi, and Korsmeyer–Peppas), and according to calculations, the kinetics of drug release followed the Korsmeyer–Peppas model. A comparison of thermograms revealed that the drug was present in the formulation in a non-crystalline form. Conclusion: Histological studies of the wound showed that the rate of skin tissue repair was higher in the GNP biocomposite treatment group than in the others.

By whipping air into a solution containing the pulp processing by-product black liquor, crosslinker and surfactant, stable air-in-black liquor froths were produced. The air volume in the froths was controlled by tuning the viscosity of the black liquor and the whipping time. By the selectively crosslinking the renewable lignin and hemicellulose content in the black liquor froths, lignin foams possessing a porosity of up to 88% have been produced. The porosity, pore and pore throat sizes decreased with increasing viscosity of the continuous liquid phase of the black liquor froths. The resulting lignin foams were pyrolysed to produce renewable carbon foams, which retained the shape and macropore structure of the lignin foam precursor well, opening the door to structurally designable carbon foams from lignin. The work demonstrated that froth templating using an industrial by-product is a viable low-cost method to produce both stable lignin and carbon foams.

Stable, liquid phenolic froths have been produced by whipping air into a mixture of phenolic resole, catalyst and surfactant. These liquid froths can be moulded into desired shapes and cured to produce open porous phenolic foams. This method, which we call froth templating, has been scaled to produce macroporous phenolic foam panels with a size of 400 mm × 400 mm × 50 mm. The density of the phenolic foams can be tuned from 0.44 g/cm3 to 0.18 g/cm3 by controlling the energy input into the liquid formulation, i.e. whipping speed and time. Accordingly, the phenolic foams had elastic moduli ranging from 200 MPa to 50 MPa. The phenolic foams were pyrolysed to produce carbon foams with a carbon yield of 48%. The carbon foams had an open porous structure replicating the phenolic foam precursor and electric conductivity of 17 S/m. Keywords: Phenolic foams, Froth templating, Carbon foams, Mechanical properties

Nonaqueous foams were successfully produced by mechanically beating air into liquid epoxy resin, surfactant, and silica particle mixtures and used as templates to produce macroporous polymers. The air bubbles introduced into the epoxy formulations served as templates for the pores of the cured epoxy foams. The addition of silica particles into the resin mixture resulted in an increased viscosity of the formulation, thus enhancing the stability of the liquid epoxy froths, which could then be thermally cured at 60 °C. Increasing the silica loading in the formulation resulted in an increase of the foam density and decrease of the average pore size of the epoxy foams. The epoxy foams containing silica exhibited a hierarchical pore structure, where large pores were surrounded by smaller pores, and enhanced stiffness as compared to the control epoxy foams with a monomodal pore size distribution.

A new synthetic procedure for the preparation of 5,6-dihydrofuro[2,3-d]pyrimidin-2(3H)-one (3) and its deoxyriboside 8 is reported. Compound 3 undergoes nucleophilic reactions with various agents to yield 5-substituted uracil derivatives. The dehydro derivative of 3, furo[2,3-d]pyrimidin-2(3H)-one (18) was synthesized by cyclization of BVU 15, which made us develop a reproducible and high yield method for the synthesis of BV(D)U. Starting from 18, the α-deoxyriboside 20 and the β-riboside 22 were prepared.

5-Bromoethynyluracil and its deoxyriboside can be prepared in good yields starting from dibromovinyluracil, which is accesible by literature methods. 5

5-Bromoethynyluracil and its deoxyriboside can be prepared in good yields starting from dibromovinyluracil, which is accesible by literature methods. 5

A new synthetic procedure for the preparation of 5,6-dihydrofuro[2,3-d]pyrimidin-2(3H)-one (3) and its deoxyriboside 8 is reported. Compound 3 undergoes nucleophilic reactions with various agents to yield 5-substituted uracil derivatives. The dehydro derivative of 3, furo[2,3-d]pyrimidin-2(3H)-one (18) was synthesized by cyclization of BVU 15, which made us develop a reproducible and high yield method for the synthesis of BV(D)U. Starting from 18, the α-deoxyriboside 20 and the β-riboside 22 were prepared.