The journey of multifunctional bone scaffolds fabricated from traditional toward modern techniques

As a bone scaffold,meeting all basic requirements besides dealing with other bone-related issues-bone cancer and accelerated regeneration-is not expected from traditional scaffolds,but a newer class of scaffolds called multifunctional.From a clinical point of view,being a multifunctional scaffold means reducing in healing time,direct costs-medicine,surgery,and hospitalization-and indirect costs-loss of mobility,losing job,and pain.The main aim of the present review is following the multifunctional bone scaffolds trend to deal with both bone regeneration and cancer therapy.Special consideration is given to different fabrication techniques which have been applied to yield these materials spanning from traditional to modern ones.Moreover,the hierarchical structure of bone plus bone cancers and available medicines to them are introduced to familiarize the potential reader of review with the pluri-disciplinary essence of the field.Eventually,a brief discussion relating to the future trend of these materials is provided.

Particle agglomeration and interphase interactions affect Young’s modulus of nanobiocomposites:eyes at mathematical modeling

Computational modeling is a new approach to optimize Young’s modulus of scaffolds by performing a minimal number of experiments.However,presenting a modeling algorithm to predict Young’s modulus and characterize the governing parameters is a challenging task.Here,a novel modeling approach has been proposed to estimate Young’s modulus of scaffolds,considering particle agglomeration and interphase interactions.Employing the characteristic parameters of these two phenomena,we modified the Maxwell model using a simple three-step algorithm to determine the optimal value of these parameters and predict Young’s modulus.Interestingly,the model provides a precision of more than 95%for all the studied cases and presents a remarkably better performance compared to the two other models.For instance,the proposed model has reduced the average absolute relative error of Young’s modulus of poly(3-hydroxybutyrate)-keratin/hydroxyapatite nanorods from 25.1%to 0.08%,demonstrating the high efficiency of this model in predicting Young’s modulus of scaffolds.The results of this study could lighten the way of fabricating nanobiocomposites with optimal mechanical properties,spending lower cost and energy.

Electrospun Aloe Vera Extract Loaded Polycaprolactone Scaffold for Biomedical Applications:A Promising Candidate for Corneal Stromal Regeneration

Corneal diseases,the second leading cause of global vision loss affecting over 10.5 million people,underscores the unmet demand for corneal tissue replacements.Given the scarcity of fresh donor corneas and the associated risks of immune rejection,corneal tissue engineering becomes imperative.Developing nanofibrous scaffolds that mimic the natural corneal structure is crucial for creating transparent and mechanically robust corneal equivalents in tissue engineering.Herein,Aloe Vera Extract(AVE)/Polycaprolactone(PCL)nanofibrous scaffolds were primed using electrospinning.The electrospun AVE/PCL fibers exhibit a smooth,bead-free morphology with a mean diameter of approximately 340±95 nm and appropriate light transparency.Mechanical measurements reveal Young’s modulus and ultimate tensile strength values of around 3.34 MPa and 4.58 MPa,respectively,within the range of stromal tissue.In addition,cell viability of AVE/PCL fibers was measured against Human Stromal Keratocyte Cells(HSKCs),and improved cell viability was observed.The cell-fiber interactions were investigated using scanning electron microscopy.In conclusion,the incorporation of Aloe Vera Extract enhances the mechanical,optical,hydrophilic,and biological properties of PCL fibers,positioning PCL/AVE fiber scaffolds as promising candidates for corneal stromal regeneration.

Fabrication of Porous Mg-Zn Scaffold through Modified Replica Method for Bone Tissue Engineering

Biodegradable scaffolds are essential parts in hard tissue engineering. A highly porous magnesium-zinc （Mg-Zn 4 wt.%） scaffold with different Mg-Zn powder to liquid media ratios （50 wt.%, 70 wt.% and 90 wt.%） and different concentrations of ethanol （0 vol.%, 10 vol.%, 20 vol.% and 40 vol.%） were prepared through modified replica method. The mechanical properties were assessed through compression test and the structures of scaffolds were examined by Scanning Electron Microscope （SEM）. Results show that, the increase in Mg-Zn powder to liquid media ratio （50 wt.% to 90 wt.%） in ethanol free slurry, increases the thickness of struts （37 lam to 74 lam） and the plateau stress （0.5 MPa to 1.4 MPa）. The results obtained from X-ray Diffractometry （XRD） and compression test indicate that consuming ethanol in liquid media of replica, results in higher plateau stress by 46% due to less Mg-water reaction and no formation of Mg（OH）2 in the scaffold. The results of porosity measurement indicate that water-ethanol mixture composition and different solid fractions have no significant effects on true and apparent porosities of the fabricated scaffolds.