Publications in April 2016 - Tissue Engineering

In April 2016, 268 publications about chitosan were released. In addition to China (52) and the United States (25), Brazil (15) is on the third place of nations with the most publications. The following studies deal with chitosan as drug delivery system to support regeneration of dermal tissue or articular cartilage.

Table: List of scientific journals, which published the highest number of chitosan-related articles in April 2016.
Source: GoPubMed

Gelatin/Carboxymethyl chitosan based scaffolds for dermal tissue engineering applications

Agarwal T., Narayan R., Maji S. et al. International journal of biological macromolecules, 93(Pt B):1499-1506. Epub April 2016. doi: 10.1016/j.ijbiomac.2016.04.028.

Scaffolds consisting of carboxymethyl chitosan and gelatin were prepared by freeze drying method. Different ratios of chitosan (medium molecular weight, 75-85% degree of deacetylation) and gelatin scaffolds were tested regarding their chemical and biological characteristics, as well as drug release profile.

RESULTS:

• Highly porous scaffolds (pore size 90-170 µm)
• High water uptake (400-1100%)
• High water retention capacity (>300%)
• Degradation of scaffolds by collagenase depends on amount of gelatin
• All formulations improved adhesion, spreading, growth and proliferation of 3T3 mouse fibroblasts
• Expression of biomarker genes for proliferation and angiogenesis
• Prolonged release of model substances ampicillin and bovine serum albumin

Conclusion: Gelatin-carboxymethyl chitosan scaffolds have desired properties for possible application in dermal tissue engineering. Scaffolds support proliferation of mouse fibroblast cells and could be used as drug delivery vehicle.

Source: https://www.ncbi.nlm.nih.gov/pubmed/27086289

The effect of polymer size and charge of molecules on permeation through synovial membrane and accumulation in hyaline articular cartilage

Sterner B., Harms M., Wöll S. et al. European Journal of Pharmaceutics and Biopharmaceutics. 101 126–136: April 2016. doi: 10.1016/j.ejpb.2016.02.004.

New drug delivery systems for joint related diseases demand for a longer residence time in the joint. Therefore, research about transport and retention events within the joint need to be conducted. In the study, distribution ability of chitosans and HEMA-Co-TMAP (HCT) polymers through bovine cartilage tissue was tested. Chitosan 95/5 (95% degree of deacetylation/viscosity, measured in 1% acetic acid), chitosan 75/5 (95% DDA/viscosity) and chitosan oligomers were purchased from HMC. HCT was synthesized with different molecular weights and different degrees of substitution (positive charged TMAP) by Merck. Results show that accumulation of tested compounds in the tissue correlates with their positive charge density.

Conclusion: Residence time inside the cartilage matrix could be prolonged by modification of molecular size and charge of the delivery substance.

Source: https://www.ncbi.nlm.nih.gov/pubmed/26876928