摘要：Sodium alginate(SA)/chitosan(CH)polyelectrolyte scaffold is a suitable substrate for tissue-engineering *** present study deals with further improvement in the tensile strength and biological properties of this type of scaffold to make it a potential template for bone-tissue *** experimented with adding 0%–15%(volume fraction)gelatin(GE),a protein-based biopolymer known to promote cell adhesion,proliferation,and *** resulting tri-polymer complex was used as bioink to fabricate SA/CH/GEmatrices by three-dimensional(3D)*** studies using scanning electron microscopy revealed the microfibrous porous architecture of all the structures,which had a pore size range of 383–419μm.X-ray diffraction and Fourier-transform infrared spectroscopy analyses revealed the amorphous nature of the scaffold and the strong electrostatic interactions among the functional groups of the polymers,thereby forming polyelectrolyte complexes which were found to improve mechanical properties and structural *** scaffolds exhibited a desirable degradation rate,controlled swelling,and hydrophilic characteristics which are favorable for bone-tissue *** tensile strength improved from(386±15)to(693±15)kPa due to the increased stiffness of SA/CH scaffolds upon addition of *** enhanced protein adsorption and in vitro bioactivity(forming an apatite layer)confirmed the ability of the SA/CH/GE scaffold to offer higher cellular adhesion and a bone-like environment to cells during the process of tissue *** vitro biological evaluation including the MTT assay,confocal microscopy analysis,and alizarin red S assay showed a significant increase in cell attachment,cell viability,and cell proliferation,which further improved biomineralization over the scaffold *** addition,SA/CH containing 15%gelatin designated as SA/CH/GE15 showed superior performance to the other fabricated 3D structures,demonstrating its pote

摘要：Nuclear safety is a global growing concern,where ionizing radiation(IR)is a major injury factor resulting in serious damage to *** detection of IR is usually conducted with physical dosimeters;however,biological IR detection methods are ***,a living composite hydrogel consisting of engineered bacteria and gelatin/sodium alginate was 3D-printed for the biological detection of *** strains of PrecA::egfp gene circuit-containing engineered Escherichia coli were constructed with IR-dependent fluorescence,and the DH5αstrain was finally selected due to its highest radiation response and *** bacteria were loaded in a series of gelatin/sodium alginate matrix hydrogels with different rheology,3D printability and bacterial applicability.A high-gelatin-content hydrogel containing 10%gelatin/1.25%sodium alginatewas *** optimal living composite hydrogelwas 3D-printedwith the special bioink,which reported significant green fluorescence underγ-ray *** living composite hydrogel provides a biological strategy for the detection of environmental ionizing radiation.

摘要：Wounds heal through a complex process including four *** interruption or interference in healing process can prevent wound *** is one of the most common complications preventing wounds from *** this study,we investigated the fibroblast cell morphology and behavior of a gelatin-based hydrogel containing anthocyanin to determine whether it can be used for early detection of *** experimental results ascertained that 6 h after culturing the fibroblasts,they could be well attached to the surface of the hydrogel,and 48 h after seeding,they were spread over the surface and connected with each *** the addition of a low dose of anthocyanin,the vitality of the cell increased,and the results of the ATR-FTIR analysis showed that anthocyanin could eliminate remaining glutaraldehyde free *** also could change its color after the addition of bacterial ***,hydrogels containing black carrot anthocyanin may be a potential therapeutic and diagnostic strategy to promote wound healing and early detection of infection.

摘要：Injection therapy for diabetes has poor patient compliance,and the pain occurring at the site of subcutaneous injections causes significant inconvenience to diabetic *** this work,to demonstrate the benefits of an alternative drug delivery technique that overcomes these issues,methacrylated gelatin hydrogel-forming microneedles integrated with metformin were developed to adjust blood glucose levels in diabetic *** methacryloyl microneedles(GelMA-MNs)with different degrees of substitution were successfully prepared by a micro-molding *** resultant GelMA-MNs exhibited excellent mechanical properties and moisture ***,an anti-diabetic drug,was further encapsulated into the GelMA-MNs,and its release rate could be controlled by the three-dimensional cross-linked network of microneedles,thereby exhibiting sustained drug release behaviors in vitro and implying a better therapeutic effect compared with that of subcutaneous injection in diabetic *** drug release period could be significantly prolonged by improving the cross-link density of *** results of hypoglycemic effect evaluation show that the application of GelMA-MNs for transdermal delivery in diabetic rats has promising benefits for diabetes treatment.

摘要：Cell-laden cardiac patches have recently been emerging to renew cellular sources for myocardial infarction(MI,commonly know as a heart attack)***,the fabrication of cell-laden patches with porous structure remains challenging due to the limitations of currently available hydrogels and existing processing *** present study utilized a bioprinting technique to fabricate hydrogel patches and characterize them in terms of printability,mechanical and biological ***-laden hydrogel(or bio-ink)was formulated from alginate dialdehyde(ADA)and gelatin(GEL)to improve the printability,degradability as well as *** groups of hydrogel compositions were designed to investigate the influence of the oxidation degree of ADA and hydrogels concentration on the properties of printed ***-GEL hydrogels have generally shown favorable for living cells(***926 cells and hybrid human umbilical vein endothelial cell line).The hydrogel with an oxidation degree of 10%and a concentration ratio of 70/30(or 10%ADA70-GEL30)demonstrated the best printability among the groups *** hydrogels were also bioprinted with the living cells(***926),and the scaffolds printed were then subject to the cell culture for 7 *** results illustrate that the scaffolds bioprinted from 10%ADA70–GEL30 hydrogels had the best homogenous cell distribution and also the highest cell *** together,in the present study we synthesized a newly formulated bio-ink from ADA and GEL and for the fist time,used them to bioprint cardiac patches,which have the potential to be used in MI repair.

摘要：The three-dimensional (3D)bioprinting technology has progressed tremendously over the past *** controlling the size, shape,and architecture of the bioprinted constructs,3D bioprinting allows for the fabrication of tissue/organ-like constructs with strong structural-functional similarity with their in vivo counterparts at high *** bioink,a blend of biomaterials and living cells possessing both high biocompatibility and printability,is a critical component of *** particular, gelatin methacryloyl (GelMA)has shown its potential as a viable bioink material due to its suitable biocompatibility and readily tunable physicochemical *** GelMA-based bioinks and relevant bioprinting strategies for GelMA bioprinting are briefly reviewed.

摘要：Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the *** their widespread utilization and numerous advantages,the development of suitable novel biomaterials for extrusion-based 3D printing of scaffolds that support cell attachment,proliferation,and vascularization remains a ***-material composite hydrogels present incredible potential in this ***,in this work,a multi-material composite hydrogel with a promising formulation of chitosan/gelatin functionalized with egg white was developed,which provides good printability and shape *** addition,a series of comparative analyses of different crosslinking agents and processes based on tripolyphosphate(TPP),genipin(GP),and glutaraldehyde(GTA)were investigated and compared to select the ideal crosslinking strategy to enhance the physicochemical and biological properties of the fabricated *** of the results indicate that the composite hydrogel and the resulting scaffolds utilizing TPP crosslinking have great potential in tissue engineering,especially for supporting neo-vessel growth into the scaffold and promoting angiogenesis within engineered tissues.