Insights into Nano-and Micro-Structured Scaffolds for Advanced Electrochemical Energy Storage

Adopting a nano-and micro-structuring approach to fully unleashing the genuine potential of electrode active material benefits in-depth understandings and research progress toward higher energy density electrochemical energy stor-age devices at all technology readiness levels.Due to various challenging issues,especially limited stability,nano-and micro-structured(NMS)electrodes undergo fast electrochemical performance degradation.The emerging NMS scaffold design is a pivotal aspect of many electrodes as it endows them with both robustness and electrochemical performance enhancement,even though it only occupies comple-mentary and facilitating components for the main mechanism.However,extensive efforts are urgently needed toward optimizing the stereoscopic geometrical design of NMS scaffolds to minimize the volume ratio and maximize their functionality to fulfill the ever-increasing dependency and desire for energy power source supplies.This review will aim at highlighting these NMS scaffold design strategies,summariz-ing their corresponding strengths and challenges,and thereby outlining the potential solutions to resolve these challenges,design principles,and key perspectives for future research in this field.Therefore,this review will be one of the earliest reviews from this viewpoint.

Customized scaffolds for large bone defects using 3D‑printed modular blocks from 2D‑medical images

Additive manufacturing(AM)has revolutionized the design and manufacturing of patient-specific,three-dimensional(3D),complex porous structures known as scaffolds for tissue engineering applications.The use of advanced image acquisition techniques,image processing,and computer-aided design methods has enabled the precise design and additive manufacturing of anatomically correct and patient-specific implants and scaffolds.However,these sophisticated techniques can be timeconsuming,labor-intensive,and expensive.Moreover,the necessary imaging and manufacturing equipment may not be readily available when urgent treatment is needed for trauma patients.In this study,a novel design and AM methods are proposed for the development of modular and customizable scaffold blocks that can be adapted to fit the bone defect area of a patient.These modular scaffold blocks can be combined to quickly form any patient-specific scaffold directly from two-dimensional(2D)medical images when the surgeon lacks access to a 3D printer or cannot wait for lengthy 3D imaging,modeling,and 3D printing during surgery.The proposed method begins with developing a bone surface-modeling algorithm that reconstructs a model of the patient’s bone from 2D medical image measurements without the need for expensive 3D medical imaging or segmentation.This algorithm can generate both patient-specific and average bone models.Additionally,a biomimetic continuous path planning method is developed for the additive manufacturing of scaffolds,allowing porous scaffold blocks with the desired biomechanical properties to be manufactured directly from 2D data or images.The algorithms are implemented,and the designed scaffold blocks are 3D printed using an extrusion-based AM process.Guidelines and instructions are also provided to assist surgeons in assembling scaffold blocks for the self-repair of patient-specific large bone defects.

3D-printed Mg-1Ca/polycaprolactone composite scaffolds with promoted bone regeneration

In bone tissue engineering,polycaprolactone(PCL)is a promising material with good biocompatibility,but its poor degradation rate,mechanical strength,and osteogenic properties limit its application.In this study,we developed an Mg-1Ca/polycaprolactone(Mg-1Ca/PCL)composite scaffolds to overcome these limitations.We used a melt blending method to prepare Mg-1Ca/PCL composites with Mg-1Ca alloy powder mass ratios of 5,10,and 20 wt%.Porous scaffolds with controlled macro-and microstructure were printed using the fused deposition modeling method.We explored the mechanical strength,biocompatibility,osteogenesis performance,and molecular mechanism of the Mg-1Ca/PCL composites.The 5 and 10 wt%Mg-1Ca/PCL composites were found to have good biocompatibility.Moreover,they promoted the mechanical strength,proliferation,adhesion,and osteogenic differentiation of human bone marrow stem cells(hBMSCs)of pure PCL.In vitro degradation experiments revealed that the composite material stably released Mg_(2)+ions for a long period;it formed an apatite layer on the surface of the scaffold that facilitated cell adhesion and growth.Microcomputed tomography and histological analysis showed that both 5 and 10 wt%Mg-1Ca/PCL composite scaffolds promoted bone regeneration bone defects.Our results indicated that the Wnt/β-catenin pathway was involved in the osteogenic effect.Therefore,Mg-1Ca/PCL composite scaffolds are expected to be a promising bone regeneration material for clinical application.Statement of significance:Bone tissue engineering scaffolds have promising applications in the regeneration of critical-sized bone defects.However,there remain many limitations in the materials and manufacturing methods used to fabricate scaffolds.This study shows that the developed Ma-1Ca/PCL composites provides scaffolds with suitable degradation rates and enhanced boneformation capabilities.Furthermore,the fused deposition modeling method allows precise control of the macroscopic morphology and microscopic porosity of the scaffold.The obtained porous scaffolds can significantly promote the regeneration of bone defects.

In vitro investigations on the effects of graphene and graphene oxide on polycaprolactone bone tissue engineering scaffolds

Polycaprolactone(PCL)scaffolds that are produced through additive manufacturing are one of the most researched bone tissue engineering structures in the field.Due to the intrinsic limitations of PCL,carbon nanomaterials are often investigated to reinforce the PCL scaffolds.Despite several studies that have been conducted on carbon nanomaterials,such as graphene(G)and graphene oxide(GO),certain challenges remain in terms of the precise design of the biological and nonbiological properties of the scaffolds.This paper addresses this limitation by investigating both the nonbiological(element composition,surface,degradation,and thermal and mechanical properties)and biological characteristics of carbon nanomaterial-reinforced PCL scaffolds for bone tissue engineering applications.Results showed that the incorporation of G and GO increased surface properties(reduced modulus and wettability),material crystallinity,crystallization temperature,and degradation rate.However,the variations in compressive modulus,strength,surface hardness,and cell metabolic activity strongly depended on the type of reinforcement.Finally,a series of phenomenological models were developed based on experimental results to describe the variations of scaffold’s weight,fiber diameter,porosity,and mechanical properties as functions of degradation time and carbon nanomaterial concentrations.The results presented in this paper enable the design of three-dimensional(3D)bone scaffolds with tuned properties by adjusting the type and concentration of different functional fillers.

Coaxial electrohydrodynamic printing of core–shell microfibrous scaffolds with layer-specific growth factors release for enthesis regeneration

The rotator cuff tear has emerged as a significant global health concern.However,existing therapies fail to fully restore the intricate bone-to-tendon gradients,resulting in compromised biomechanical functionalities of the reconstructed enthesis tissues.Herein,a tri-layered core–shell microfibrous scaffold with layer-specific growth factors(GFs)release is developed using coaxial electrohydrodynamic(EHD)printing for in situ cell recruitment and differentiation to facilitate gradient enthesis tissue repair.Stromal cell-derived factor-1(SDF-1)is loaded in the shell,while basic fibroblast GF,transforming GF-beta,and bone morphogenetic protein-2 are loaded in the core of the EHD-printed microfibrous scaffolds in a layer-specific manner.Correspondingly,the tri-layered microfibrous scaffolds have a core–shell fiber size of(25.7±5.1)μm,with a pore size sequentially increasing from(81.5±4.6)μm to(173.3±6.9)μm,and to(388.9±6.9μm)for the tenogenic,chondrogenic,and osteogenic instructive layers.A rapid release of embedded GFs is observed within the first 2 d,followed by a faster release of SDF-1 and a slightly slower release of differentiation GFs for approximately four weeks.The coaxial EHD-printed microfibrous scaffolds significantly promote stem cell recruitment and direct their differentiation toward tenocyte,chondrocyte,and osteocyte phenotypes in vitro.When implanted in vivo,the tri-layered core–shell microfibrous scaffolds rapidly restored the biomechanical functions and promoted enthesis tissue regeneration with native-like bone-to-tendon gradients.Our findings suggest that the microfibrous scaffolds with layer-specific GFs release may offer a promising clinical solution for enthesis regeneration.

Numerical Analysis of Permeability of Functionally Graded Scaffolds

In this work,we numerically study the hydrodynamic permeability of new-generation artificial porous materials used as scaffolds for cell growth in a perfusion bioreactor.We consider two popular solid matrix designs based on triply periodic minimal surfaces,the Schwarz P(primitive)and D(diamond)surfaces,which enable the creation of materials with controlled porosity gradients.The latter property is crucial for regulating the shear stress field in the pores of the scaffold,which makes it possible to control the intensity of cell growth.The permeability of functionally graded materials is studied within the framework of both a microscopic approach based on the Navier-Stokes equation and an averaged description of the liquid filtration through a porous medium based on the equations of the Darcy or Forchheimer models.We calculate the permeability coefficients for both types of solid matrices formed by Schwarz surfaces,study their properties concerning forward and reverse fluid flows,and determine the ranges of Reynolds number for which the description within the Darcy or Forchheimer model is applicable.Finally,we obtain a shear stress field that varies along the sample,demonstrating the ability to tune spatially the rate of tissue growth.

Advanced strategies for 3D-printed neural scaffolds:materials,structure,and nerve remodeling

Nerve regeneration holds significant potential in the treatment of various skeletal and neurological disorders to restore lost sensory and motor functions.The potential of nerve regeneration in ameliorating neurological diseases and injuries is critical to human health.Three-dimensional(3D)printing offers versatility and precision in the fabrication of neural scaffolds.Complex neural structures such as neural tubes and scaffolds can be fabricated via 3Dprinting.This reviewcomprehensively analyzes the current state of 3D-printed neural scaffolds and explores strategies to enhance their design.It highlights therapeutic strategies and structural design involving neural materials and stem cells.First,nerve regeneration materials and their fabrication techniques are outlined.The applications of conductive materials in neural scaffolds are reviewed,and their potential to facilitate neural signal transmission and regeneration is highlighted.Second,the progress in 3D-printed neural scaffolds applied to the peripheral and central nerves is comprehensively evaluated,and their potential to restore neural function and promote the recovery of different nervous systems is emphasized.In addition,various applications of 3D-printed neural scaffolds in peripheral and neurological diseases,as well as the design strategies of multifunctional biomimetic scaffolds,are discussed.

Enhanced axonal regeneration and functional recovery of the injured sciatic nerve in a rat model by lithium-loaded electrospun nanofibrous scaffolds

Increasing evidence indicates that engineered nerve grafts have great potential for the regeneration of peripheral nerve injuries(PNIs).While most studies have focused only on the topographical features of the grafts,we have considered both the biophysical and biochemical manipulations in our applied nanoscaffold.To achieve this,we fabricated an electrospun nanofibrous scaffold(ENS)containing polylactide nanofibers loaded with lithium(Li)ions,a Wnt/β-catenin signaling activator.In addition,we seeded human adipose-derived mesenchymal stem cells(hADMSCs)onto this engineered scaffold to examine if their differentiation toward Schwann-like cells was induced.We further examined the efficacy of the scaffolds for nerve regeneration in vivo via grafting in a PNI rat model.Our results showed that Li-loaded ENSs gradually released Li within 11 d,at concentrations ranging from 0.02 to(3.64±0.10)mmol/L,and upregulated the expression of Wnt/β-catenin target genes(cyclinD1 and c-Myc)as well as those of Schwann cell markers(growth-associated protein 43(GAP43),S100 calcium binding protein B(S100B),glial fibrillary acidic protein(GFAP),and SRY-box transcription factor 10(SOX10))in differentiated hADMSCs.In the PNI rat model,implantation of Li-loaded ENSs with/without cells improved behavioral features such as sensory and motor functions as well as the electrophysiological characteristics of the injured nerve.This improved function was further validated by histological analysis of sciatic nerves grafted with Li-loaded ENSs,which showed no fibrous connective tissue but enhanced organized myelinated axons.The potential of Li-loaded ENSs in promoting Schwann cell differentiation of hADMSCs and axonal regeneration of injured sciatic nerves suggests their potential for application in peripheral nerve tissue engineering.

Recognizing and preventing complications regarding bioresorbable scaffolds during coronary interventions

The evolution of coronary intervention techniques and equipment has led to more sophisticated procedures for the treatment of highly complex lesions.However,as a result,the risk of complications has increased,which are mostly iatrogenic and often include equipment failure.Stent dislodgement warrants vigilance for the early diagnosis and a stepwise management approach is required to either expand or retrieve the lost stent.In the era of bioresorbable scaffolds that are not radiopaque,increased caution is required.Intravascular imaging may assist in detecting the lost scaffold in cases of no visibility fluoroscopically.Adequate lesion preparation is the key to minimizing the possibility of equipment loss;however,in the case that it occurs,commercially available and improvised devices and techniques may be applied.

Topology optimization of microstructure and selective laser meltingfabrication for metallic biomaterial scaffolds

The precise design and fabrication of biomaterial scaffolds is necessary to provide a systematic study for bone tissue engineering. Biomaterial scaffolds should have sufficient stiffness and large porosity. These two goals generally contradict since larger porosity results in lower mechanical properties. To seek the microstructure of maximum stiffness with the constraint of volume fraction by topology optimization method, algorithms and programs were built to obtain 2D and 3D optimized microstructure and then they were transferred to CAD models of STL format. Ti scaffolds with 30% volume fraction were fabricated using a selective laser melting （SLM） technology. The architecture and pore shape in the metallic biomaterial scaffolds were relatively precise reproduced and the minimum mean pore size was 231μm. The accurate fabrication of intricate microstructure has verified that the SLM process is suitable for fabrication of metallic biomaterial scaffolds.

Smart scaffolds in bone tissue engineering: A systematic review of literature

AIM: To improve osteogenic differentiation and attachment of cells.METHODS: An electronic search was conducted inPub Med from January 2004 to December 2013. Studies which performed smart modifications on conventional bone scaffold materials were included. Scaffolds with controlled release or encapsulation of bioactive molecules were not included. Experiments which did not investigate response of cells toward the scaffold(cell attachment, proliferation or osteoblastic differentiation) were excluded. RESULTS: Among 1458 studies, 38 met the inclusion and exclusion criteria. The main scaffold varied extensively among the included studies. Smart modifications included addition of growth factors(group Ⅰ-11 studies), extracellular matrix-like molecules(group Ⅱ-13 studies) and nanoparticles(nano-HA)(group Ⅲ-17 studies). In all groups, surface coating was the most commonly applied approach for smart modification of scaffolds. In group I, bone morphogenetic proteins were mainly used as growth factor stabilized on polycaprolactone(PCL). In group Ⅱ, collagen 1 in combination with PCL, hydroxyapatite(HA) and tricalcium phosphate were the most frequent scaffolds used. In the third group, nano-HA with PCL and chitosan were used the most. As variable methods were used, a thorough and comprehensible compare between the results and approaches was unattainable.CONCLUSION: Regarding the variability in methodology of these in vitro studies it was demonstrated that smart modification of scaffolds can improve tissue properties.

Evaluation of corneal cell growth on tissue engineering materials as artificial cornea scaffolds

The keratoprosthesis(KPro;artificial cornea)is a special refractive device to replace human cornea by using heterogeneous forming materials for the implantation into the damaged eyes in order to obtain a certain vision.The main problems of artificial cornea are the biocompatibility and stability of the tissue particularly in penetrating keratoplasty.The current studies of tissue-engineered scaffold materials through comprising composites of natural and synthetic biopolymers together have developed a new way to artificial cornea.Although a wide agreement that the long-term stability of these devices would be greatly improved by the presence of cornea cells,modification of keratoprosthesis to support cornea cells remains elusive.Most of the studies on corneal substrate materials and surface modification of composites have tried to improve the growth and biocompatibility of cornea cells which can not only reduce the stimulus of heterogeneous materials,but also more importantly continuous and stable cornea cells can prevent the destruction of collagenase.The necrosis of stroma and spontaneous extrusion of the device,allow for maintenance of a precorneal tear layer,and play the role of ensuring a good optical surface and resisting bacterial infection.As a result,improvement in corneal cells has been the main aim of several recent investigations;some effort has focused on biomaterial for its well biological properties such as promoting the growth of cornea cells.The purpose of this review is to summary the growth status of the corneal cells after the implantation of several artificial corneas.

Design and criteria of electrospun fibrous scaffolds for the treatment of spinal cord injury

The complex pathophysiology of spinal cord injury may explain the current lack of an effective therapeutic approach for the regeneration of damaged neuronal cells and the recovery of motor functions. Many efforts have been performed to design and develop suitable scaffolds for spinal cord regeneration, keeping in mind that the reconstruction of a pro-regenerative environment is the key challenge for an effective neurogenesis. The aim of this review is to outline the main features of an ideal scaffold, based on biomaterials, produced by the electrospinning technique and intended for the spinal cord regeneration. An overview of the poly- mers more investigated in the production of neural fibrous scaffolds is also provided.

Fabrication and Characterization of Poly Lactic Acid Scaffolds by Fused Deposition Modeling for Bone Tissue Engineering

Three-dimensional porous poly-lactic acid(PLA) scaffold was fabricated using fused deposition modeling(FDM) method including 30%, 50% and 70% nominal porosity. Study of phases in initial polymeric material and printed scaffolds was done by X-ray diffraction(XRD), and no significant phase difference was observed due to the manufacturing process, and the poly-lactic acid retains its crystalline properties. The results of the mechanical properties evaluation by the compression test show that the mechanical properties of the scaffold have decreased significantly with increasing the porosity of scaffold. The microstructure of scaffolds were studied by scanning electron microscope(SEM), showing that the pores had a regular arrangement and their morphology changed with porosity change. The mechanical properties of the poly-lactic acid scaffolds printed using fused deposition modeling, can be adapted to the surrounding tissue, by porosity change.

Scaffolds based therapy for osteochondral lesions of the talus:A systematic review

AIM To clarify the effectiveness of scaffold-based therapy for osteochondral lesions of the talus(OLT). METHODS A systematic search of MEDLINE and EMBASE databases was performed during August 2016 and updated in January 2017. Included studies were evaluated with regard to the level of evidence(LOE) and quality of evidence(QOE) using the Modified Coleman Methodology Score. Variable reporting outcome data, clinical outcomes, and the percentage of patients who returned to sport at previous level were also evaluated. RESULTS Twenty-eight studies for a total of 897 ankles were included; 96% were either LOE Ⅲ or Ⅳ. Studies were designated as either of poor or fair quality. There were 30 treatment groups reporting six different scaffold repair techniques: 13 matrix-induced autologous chondrocyte transplantation(MACT), nine bone marrow derived cell transplantation(BMDCT), four autologous matrixinduced chondrogeneis(AMIC), and four studies of other techniques. The categories of general demographics(93%) and patient-reported outcome data(85%) were well reported. Study design(73%), imaging data(73%), clinical variables(49%), and patient history(30%) were also included. The weighted mean American Orthopaedic Foot and Ankle Society(AOFAS) score at final follow-up was: 86.7 in MACT, 88.2 in BMDCT, and 82.3 in AMIC. Eight studies reported that a weighted mean of 68.3% ofpatients returned to a previous level of sport activity. CONCLUSION Scaffold-based therapy for OLT may produce favorable clinical outcomes, but low LOE, poor QOE, and variability of the data have confounded the effectiveness of this treatment.

Restoring nervous system structure and function using tissue engineered living scaffolds

Neural tissue engineering is premised on the integration of engineered living tissue with the host nervous system to directly restore lost function or to augment regenerative capacity following ner- vous system injury or neurodegenerative disease. Disconnection of axon pathways - the long-distance fibers connecting specialized regions of the central nervous system or relaying peripheral signals - is a common feature of many neurological disorders and injury. However, functional axonal regenera- tion rarely occurs due to extreme distances to targets, absence of directed guidance, and the presence of inhibitory factors in the central nervous system, resulting in devastating effects on cognitive and sensorimotor function. To address this need, we are pursuing multiple strategies using tissue engi- neered ＂living scaffolds＂, which are preformed three-dimensional constructs consisting of living neural cells in a defined, often anisotropic architecture. Living scaffolds are designed to restore function by serving as a living labeled pathway for targeted axonal regeneration - mimicking key developmental mechanisms- or by restoring lost neural circuitry via direct replacement of neurons and axonal tracts. We are currently utilizing preformed living scaffolds consisting of neuronal dusters spanned by long axonal tracts as regenerative bridges to facilitate long-distance axonal regeneration and for targeted neurosurgical reconstruction of local circuits in the brain. Although there are formidable challenges in predinical and clinical advancement, these living tissue engineered constructs represent a promising strategy to facilitate nervous system repair and functional recovery.

Efficacy of chitosan and sodium alginate scaffolds for repair of spinal cord injury in rats

Spinal cord injury results in the loss of motor and sensory pathways and spontaneous regeneration of adult mammalian spinal cord neurons is limited. Chitosan and sodium alginate have good biocompatibility, biodegradability, and are suitable to assist the recovery of damaged tissues, such as skin, bone and nerve. Chitosan scaffolds, sodium alginate scaffolds and chitosan-sodium alginate scaffolds were separately transplanted into rats with spinal cord hemisection. Basso-Beattie-Bresnahan locomotor rating scale scores and electrophysiological results showed that chitosan scaffolds promoted recovery of locomotor capacity and nerve transduction of the experimental rats.Sixty days after surgery, chitosan scaffolds retained the original shape of the spinal cord. Compared with sodium alginate scaffolds- and chitosan-sodium alginate scaffolds-transplanted rats, more neurofilament-H-immunoreactive cells （regenerating nerve fibers） and less glial fibrillary acidic protein-immunoreactive cells （astrocytic scar tissue） were observed at the injury site of experimental rats in chitosan scaffold-transplanted rats. Due to the fast degradation rate of sodium alginate, sodium alginate scaffolds and composite material scaffolds did not have a supporting and bridging effect on the damaged tissue. Above all, compared with sodium alginate and composite material scaffolds, chitosan had better biocompatibility, could promote the regeneration of nerve fibers and prevent the formation of scar tissue,and as such, is more suitable to help the repair of spinal cord injury.

Additive manufacturing of biodegradable magnesium implants and scaffolds: Review of the recent advances and research trends

Synthetic grafting needs improvements to eliminate secondary surgeries for the removal of implants after healing of the defected tissues.Tissue scaffolds are engineered to serve as temporary templates,which support the affected tissue and gradually degrade through the healing period.Beside mechanical function to withstand the anatomic loading conditions,scaffolds should also provide a decent biological function for the diffusion of nutrients and oxygen to the cells,and excretion of the wastes from the cells to promote the new tissue growth and vascularization.Moreover,the degradation byproducts of the scaffolds should be safe to the human body.Development of such multifunctional scaffolds requires selection of the right material,design,and manufacturing method.Mg has been recognized as the prominent biodegradable metal with regards to its mechanical properties matching to that of human bone,degradability in the body fluid,and its ability to stimulate new tissue growth.Scaffolds with intricate porous structures can be designed according to the patient-specific anatomic data using computer aided designs.Additive manufacturing(AM)is the right method to materialize these models rapidly with reasonably acceptable range of dimensional accuracy.Thus,the recent research trend is to develop ideal scaffolds using biodegradable Mg through AM methods.This review compiles and discusses the available literature on the AM of biodegradable Mg parts from the viewpoints of material compositions,process conditions,formation quality,dimensional accuracy,microstructure,biodegradation,and mechanical properties.The current achievements are summarized together,and future research directions are identified to promote clinical applications of biodegradable Mg through the advancement of AM.

Immobilization of Decellularized Valve Scaffolds with Arg-Gly-Asp-containing Peptide to Promote Myofibroblast Adhesion

The cell adhesive properties of decellularized valve scaffolds were promoted by immobilization of valve scaffold with arginine-glycine-aspartic acid （RGD）-containing peptides. Porcine aortic valves were decellularized with trypsin/EDTA, and detergent Triton X-100. With the help of a coupling reagent Sulfo-LC-SPDP, the valve scaffolds were immobilized with glycine-arginine-glycine-aspartic acid-serine-proline-cysteine （GRGDSPC） peptide. X-ray photoelectron spectroscopy （XPS） was used for surface structure analysis. Myofibroblasts harvested from rats were seeded onto the valve scaffolds. Cell count by using microscopy and modified MTT assay were performed to assess cell adhesion. Based on the spectra of XPS, the conjugation of GRGDSPC peptide with decellularized valve scaffolds was confirmed. Both cell count and MTT assay showed that myofibroblasts were much easier to adhere to the modified valve scaffolds, which was also confirmed histologically. Our findings suggest that it is feasible to immobilize RGD-containing peptides onto decellularized valve scaffolds. And the technique can effectively promote cell adhesion, which is beneficial for in vitro tissue engineering of heart valves.

3D PLLA/Nano-hydroxyapatite Scaffolds with Hierarchical Porous Structure Fabricated by Low-temperature Deposition Manufacturing

A new Precision Extrusion nozzle based ball screw transmission was developed. 3D hierarchical porous PLLA/nano-Hydroxyapatite（PLLA/nHA） scaffolds were fabricated by low-temperature deposition manufacturing. Scaffolds with macropores of 200-500 rtm and micropores about 10 pm were fabricated through a thorough study and control of the processing parameters, in which the processing path and speed of material extrusion determine the macropores and there is a suitable temperature zone for fabricating qualified macropores. Micropore morphology can be controlled by adjusting supercooling of solvent crystallization or adding water into the solvent system. The compressive modulus of the scaffolds in air and phosphate buffer solution was measured, which increased with HA addition. In-vitro cell culture results showed a ~ood biocomoatibilitv of PLLA/HA scaffolds with the ore-osteoblastic MC3T3-E1 cells.