Biomaterials

Three dimensional (3D) bioplotting requires appropriate crosslinkers to crosslink the hydrogel precursor while simultaneously maintaining the viability of embedded cells. However, the evaluation and comparison of various types of crosslinkers in bioplotting remains underexplored to date. This paper presents our study of the inuence of three ionic crosslinkers—calcium chloride (CaCl 2), barium chloride (BaCl 2), and zinc chloride (ZnCl 2)—on the mechanical and biological properties of 3D bioplotted alginate scaolds. The scaold mechanical properties characterized included the elastic modulus, swelling, and degradation while the biological properties considered included Schwann cell viability and surface morphology. The mechanical and biological properties of the bioplotted scaolds were both dependent on the crosslinkers used for fabrication; speciically, crosslinking ions resulted in the elastic modulus of the hydrogels decreasing in the order BaCl 2 >CaCl 2 >ZnCl 2 over 42 days while Schwann cell viability decreased in the order CaCl 2 >BaCl 2 >ZnCl 2 over 7 days. Taken together, these results ooer insights that are eeective in terms of manipulating the 3D bioplotting process so as to tune and optimize the mechanical and biological performance of the plotted scaaolds for tissue engineering applications.

Crop residues are common in rural Ghana due to the predominant role agriculture plays in livelihood activities in these communities. In this paper we investigate the prospects of exploiting agricultural crop residues for rural development in Ghana through bioenergy schemes. A theoretical energy potential of 623.84 PJ per year, which is equivalent to 19,781 MW was estimated using crop production data from the Food and Agricultural Organization of the United Nations and residue-to-product ratios. Ghana has a total installed generation capacity of 4577 MW which is four times less the energy potential of crop residues in the country. Cocoa pod husks were identified as important biomass resources for energy generation as they are currently wasted. To further assess the energy potential of cocoa pod husks, different cocoa pod husks samples were collected across the six cocoa growing regions in Ghana and thermo-chemically characterised using proximate and ultimate analysis. The low levels of nitrogen and sulphur observed, together with the high heating value, suggest that cocoa pod husks and for that matter crop residues are eco-friendly feedstock that can be used to power rural communities in Ghana.