Sharif Digital Repository

Decellularized extracellular matrix (dECM) bioinks hold significant potential in the 3D bioprinting of tissue-engineered constructs (TECs). While 3D bioprinting allows for the creation of custom-designed TECs, the development of bioinks based solely on dAM, without the inclusion of supporting agents or chemical modifications, remains underexplored. In this study, we present the concentration-dependent printability and rheological properties of dAM bioinks, along with an analysis of their in vitro cellular responses. Our findings demonstrate that increasing dAM concentrations, within the range of 1 to 3% w/v, enhances the mechanical moduli of the bioinks, enabling the 3D printing of flat... 

Recently, decellularized amniotic membrane-derived hydrogels (DAMHs) have received significant attention for wound care, ocular surface reconstruction, and chondral healing. Despite the advantages of DAMHs for tissue engineering (TE), the loss of structural components during the decellularization process mitigates their mechanical strength and thus limits their practical application. Herein, we present a method for the surface modification of two-dimensional nanosilicates (laponite) as a rheological modifier to tailor the properties of DAMHs. Results show that after introducing nanosilicates, severe aggregation of the nanoparticles occurs, owing to the shielding effect of ions on the surface... 

Recently, decellularized amniotic membranes (dAM) have attracted significant interest as a valuable source for the development of shear-thinning hydrogels and bioinks. However, the inferior rheological behavior and weak mechanical durability restrict the printability of the hydrogels and their stability after three-dimensional (3D) bioprinting. Therefore, a chemical or physical modification with biocompatible components is necessary to improve dAM-derived hydrogels’ properties. The present study proposes a strategy to fabricate printable dAM-derived hydrogels (DAMHs) supplemented with sodium alginate and Laponite nanoplatelets. Rheological experiments determined the key role of Laponite... 

Although hydrogels developed based on the decellularized amniotic membrane (dAM) hold great promise for tissue engineering and regenerative medicine, the development of printable bioinks faces serious limitations considering appropriate rheological behavior and shape fidelity after 3D printing. To improve the printability of dAM, we propose that hydroxyethyl cellulose (HEC) and silicate nanoplatelets (Laponite) can be used as a thickening agent and rheology modifier, respectively. It is shown that the Laponite operates as a physical crosslinking agent through reversible non-covalent interactions between nanoplatelets and the biopolymer matrix, thus improving the storage modulus of the bioink... 

Decellularized amnion (dAM)-derived hydrogels have been extensively exploited for versatile medical and therapeutical applications, particularly for soft tissue engineering of skin, vascular graft, and endometrium. In contrast to polyacrylamide-based hydrogels, which have been extensively employed as a 3D cell culture platform, the cell response of dAM hydrogel is yet to be understood. In this study, we have prepared hydrogels containing different concentrations of dAM and systematically investigated their microstructural features, gelation kinetics, and rheological properties. The results show that dAM hydrogels possess a network of fibers with an average diameter of 56 ± 5 nm at 1% dAM,... 

In recent years, the amnion (AM) has emerged as a versatile tool for stimulating tissue regeneration and has been of immense interest for clinical applications. AM is an abundant and cost-effective tissue source that does not face strict ethical issues for biomedical applications. The outstanding biological attributes of AM, including side-dependent angiogenesis, low immunogenicity, anti-inflammatory, anti-fibrotic, and antibacterial properties facilitate its usage for tissue engineering and regenerative medicine. However, the clinical usage of thin AM sheets is accompanied by some limitations, such as handling without folding or tearing and the necessity for sutures to keep the material...