Composite material comprising pectin and calcium phosphate and method for its realisation

A method for obtaining a composite material including an aqueous solution of pectin and a suspension/solution of calcium phosphate mixed together, wherein said solution of pectin cross-links with a portion of the calcium obtained from the solution of calcium phosphate and wherein a portion of the calcium phosphate in suspension remains as inorganic phase and composite materials obtained by this method

Immunological and Differentiation Properties of Amniotic Cells Are Retained After Immobilization in Pectin Gel

Mesenchymal stromal cells from the human amniotic membrane (i.e., human amniotic mesenchymal stromal cells [hAMSCs]) of term placenta are increasingly attracting attention for their applications in regenerative medicine. Osteochondral defects represent a major clinical problem with lifelong chronic pain and compromised quality of life. Great promise for osteochondral regeneration is held in hydrogel-based constructs that have a flexible composition and mimic the physiological structure of cartilage. Cell loading within a hydrogel represents an advantage for regenerative purposes, but the encapsulation steps can modify cell properties. As pectin gels have also been explored as cell vehicles on 3D scaffolds, the aim of this study was to explore the possibility to include hAMSCs in pectin gel. Immobilization of hAMSCs into pectin gels could expand their application in cell-based bioengineering strategies. hAMSCs were analyzed for their viability and recovery from the pectin gel and for their ability to differentiate toward the osteogenic lineage and to maintain their immunological characteristics. When treated with a purposely designed pectin/hydroxyapatite gel biocomposite, hAMSCs retained their ability to differentiate toward the osteogenic lineage, did not induce an immune response, and retained their ability to reduce T cell proliferation. Taken together, these results suggest that hAMSCs could be used in combination to pectin gels for the study of novel osteochondral regeneration strategies

Polysaccharide-based hydrogels with tunable composition as 3D cell culture systems

Background:To date, cell cultures have been created either on 2-dimensional (2D) polystyrene surfaces or in 3-dimensional (3D) systems, which do not offer a controlled chemical composition, and which lack the soft environment encountered in vivo and the chemical stimuli that promote cell proliferation and allow complex cellular behavior. In this study, pectin-based hydrogels were developed and are proposed as versatile cell culture systems.Methods:Pectin-based hydrogels were produced by internally crosslinking pectin with calcium carbonate at different initial pH, aiming to control crosslinking kinetics and degree. Additionally, glucose and glutamine were added as additives, and their effects on the viscoelastic properties of the hydrogels and on cell viability were investigated.Results:Pectin hydrogels showed in high cell viability and shear-thinning behavior. Independently of hydrogel composition, an initial swelling was observed, followed by a low percentage of weight variation and a steady-state stage. The addition of glucose and glutamine to pectin-based hydrogels rendered higher cell viability up to 90%-98% after 1 hour of incubation, and these hydrogels were maintained for up to 7 days of culture, yet no effect on viscoelastic properties was detected.Conclusions:Pectin-based hydrogels that offer tunable composition were developed successfully. They are envisioned as synthetic extracellular matrix (ECM) either to study complex cellular behaviors or to be applied as tissue engineering substitutes

Sterilization treatments on polysaccharides: Effects and side effects on pectin

Thermal and irradiation treatments represent techniques used for a wide range of materials intended for different applications in the food and medical industry aimed to decontamination and sterilization of different technologic processes. Traditional treatments with vapor combined with pressure, reactive gases, and radiation can be used for sterilization of medical implants and to prevent food deterioration. On the other side, these treatments can be employed to obtain a controlled distribution of molecular weight of polymers, as reported by literature. Pectin, as many polysaccharides, may be susceptible to side effects and modifications caused by the sterilization treatments. In this perspective, physico-chemical and biological properties of pectin powders and solutions were investigated after sterilization. Traditional methods, i.e., ethylene oxide, gamma irradiation and moist heat sterilization, were compared and their effects on pectin structure were evaluated. Results indicate that each sterilization procedure affected pectin powders and solutions, resulting in a decrease of viscosity, molecular weight and rheological properties with respect of nonsterilized samples. For sterilized powders properties were better retained than for sterilized solutions, being EtO the optimal method for pectin powders and gamma rays, especially at low doses, for pectin solutions, independently of their structure and initial degree of esterification. Moist heat sterilization was found to significantly depolymerize pectin chains in solution, with the production of cytotoxic residues

Composite material comprising pectin and calcium phosphate and method for its realisation

A method for obtaining a composite material comprising an aqueous solution of pectin and a suspension/solution of calcium phosphate mixed together, wherein said solution of pectin cross-links with a portion of the calcium obtained from the solution of calcium phosphate and wherein a portion of the calcium phosphate in suspension remains as inorganic phase and composite materials obtained by this method