Pure PLLA Scaffolds Research Articles

In Situ Generation of Hydroxyapatite on Biopolymer Particles for Fabrication of Bone Scaffolds Owning Bioactivity

Hydroxyapatite (HAP) can endow a biopolymer scaffold with good bioactivity and osteoconductive ability, while the interfacial bonding is fairly weak between HAP and biopolymers. In this study, HAP was in situ generated on poly(l-lactic acid) (PLLA) particles, and then they were used to fabricate a scaffold by selective laser sintering. Detailedly, PLLA particles were first functionalized by dopamine oxide polymerization, which introduced abundance active catechol groups on the particle surface, and subsequently, the catechol groups concentrated Ca2+ ions by chelation in a simulated body fluid solution, and then, Ca2+ ions absorbed PO43- ions through electrostatic interactions for in situ nucleation of HAP. The results indicated that HAP was homogeneously generated on the PLLA particle surface, and HAP and PLLA exhibited good interfacial bonding in the HAP/PLLA scaffolds. Meanwhile, the scaffolds displayed excellent bioactivity by inducing apatite precipitation and provided a good environment for human bone mesenchymal stem cell attachment, proliferation, and osteogenic differentiation. More importantly, the ingrowth of blood vessel and the formation of new bone could be stimulated by the scaffolds in vivo, and the bone volume fraction and bone mineral density increased by 44.44 and 41.73% compared with the pure PLLA scaffolds, respectively. Serum biochemical indexes fell within the normal range, which indicated that there was no harmful effect on the normal functioning of the body after implanting the scaffold.

Electrospun Core–Shell Fibrous 2D Scaffold with Biocompatible Poly(Glycerol Sebacate) and Poly-l-Lactic Acid for Wound Healing

Biomimetic scaffolds made by synthetic materials are usually used to replace the natural tissues aimed at speeding up the skin regeneration. In this study, a flexible and cytocompatible poly(glycerol sebacate)@poly-l-lactic acid (PGS@PLLA) fibrous scaffold with a core–shell structure was fabricated by coaxial electrospinning, where the shell PLLA was used to be a skeleton with pores on the fibrous surface. The fibrous morphology with pores on the surface of the prepared fibers was observed by SEM. The core–shell microstructure of PGS@PLLA fibers was confirmed by TEM and Laser Scanning Confocal Microscopy (LSCM). In addition, the prepared fibers exhibited a strong ability to repair tissues of the skin wound, where the stability of cell security and proliferation, and the lower inflammatory response were all superior to those of pure PLLA scaffold. It’s worth noting that the percentage of skin tissue was regenerated by 95% within 14 days, which suggests the potential application for electrospun-based synthetic fibrous scaffolds on wound healing.

Preparation and osteogenic properties of poly ( L-lactic acid)/lecithin porous scaffolds with open pore structure

To investigate the preparation and osteogenic properties of poly ( L-lactic acid)(PLLA)/lecithin porous scaffolds with open pore structure. PLLA/lecithin porous scaffolds with different lecithin contents (0, 5%, 10%, 20%, 30%, 40%, 50%) were prepared by thermally induced phase separation (groups A, B, C, D, E, F, and G, respectively). Scanning electron microscopy (SEM) was used to observe the surface morphology of the scaffolds. Wide-angle X-ray diffraction (XRD) and differential scanning calorimetry (DSC) were used to detect the crystallinity of the scaffolds. The water uptake ability of the scaffolds was measured. The cell growth and viability of bone marrow mesenchymal stem cells (BMSCs) of mouse on each scaffold was assessed by cell counting kit 8 (CCK-8) method. The osteogenic differentiation ability of BMSCs on each scaffold was evaluated by alkaline phosphatase (ALP) activity. Finally, a critical-size rat calvarial bone defect model was used to evaluate the osteogenesis of the scaffolds in vivo. Micro-CT was used to reconstruct the three-dimensional model of the defect area, and the bone volume and bone mineral density were quantitatively analyzed. SEM results showed that the lecithin could slightly reduce the pore size; when lecithin content was 50%, platelet-like structure could be observed on the scaffolds. Wide angle XRD and DSC showed that the crystallinity of scaffolds gradually decreased with the increase of lecithin content. The water uptake ability test showed that the hydrophilicity of scaffolds increased with the increase of lecithin content. CCK-8 assay showed that cell activity gradually increased with the increase of culture time. After 7 days of culture, the absorbance ( A) value of groups C, D, E, and F were significantly higher than that of groups A, B, and G ( P<0.05), but no significant difference was found among groups C, D, E, and F ( P>0.05). After 14 days of osteogenic induction, with the increase of lecithin content, there was a significant difference in ALP activity of each group. The ALP activity in groups D, E, F, and G were significantly higher than that in groups A, B, and C ( P<0.05). In vivo, the results of Micro-CT examination and bone volume and bone mineral density showed that the scaffolds with 30% lecithin had the best repairing effect. Prepared by thermally induced phase separation, the cytocompatibility, osteogenic differentiation, and bone repair ability of the PLLA/lecithin porous scaffold is obviously better than that of pure PLLA scaffold. PLLA/lecithin porous scaffold with suitable lecithin content is a promising scaffold material for bone tissue engineering.

Sequential controlled-released dual-drug loaded scaffold for guided bone regeneration in a rat fenestration defect model.

A microbially-induced inflammatory periodontal disease is the main initiator to disrupt the periodontium. It is desirable to develop a newly guided bone regeneration (GBR) scaffold to accomplish the periodontal tissue regeneration for the concurrent control of inflammation. A novel therapeutic solution for GBR based on 3D multifunctional scaffolds, which combines the merits of osseous regeneration and local anti-inflammatory drug delivery, has been developed. The 3D dual-drug delivery scaffold (DDDS) loaded with parthenolide and naringin was successfully developed by thermally-induced phase separation techniques. The DDDS was hierarchically interconnected to the porous PLLA scaffold loaded with the hydrophobic parthenolide. In addition, the hydrophilic naringin loaded in chitosan microspheres was embedded in the scaffold. In vitro drug release profile results revealed that the DDDS showed an efficient sequential controlled release pattern with parthenolide delivered rapidly, followed by naringin delivered in a more sustained manner. Cell viability of MC3T3-E1 showed a combined effect of dual-drug delivery. Hemolysis of the DDDS was 1.84 ± 0.44%, which is less than that of the pure PLLA scaffold. To further evaluate the in vivo guided bone regeneration effect of the DDDS, a rat fenestration defect model was generated. The defects were harvested after 4 and 8 weeks for micro-CT and histological observation. The results suggested that the DDDS group had significantly increased the regenerated bone volume fraction compared to both the control and PLLA groups at 8 weeks, which was in parallel with the reduced expression of IL-6. This DDDS, as a GBR scaffold, might be utilized as a novel adjunctive treatment in periodontitis.

Macroporous and nanofibrous PLLA scaffolds reinforced with calcium phosphate-coated multiwalled carbon nanotubes

Scaffolds with both macro- and nanoscale structures have shown promise in tissue engineering; however, their mechanical properties are not satisfactory for load-bearing bone regeneration. In this study, calcium phosphate-coated multiwalled carbon nanotubes (MWCNTs-CaP) were developed to reinforce macroporous poly(L-lactide) (PLLA) scaffolds with nanofibrous pore walls. The scaffolds were prepared using a phase separation/particle-leaching method. One-dimensional MWCNTs-CaP were prepared via phosphorylation and mineralization. The addition of the MWCNTs-CaP did not affect the nanofibrous pore walls of the resulting PLLA scaffolds. In comparison with pure PLLA scaffolds, the compressive properties of PLLA/MWCNTs-CaP composite scaffolds were significantly improved, indicating their potential in bone regeneration applications.

Electrospinning of poly(lactic acid)/polyhedral oligomeric silsesquioxane nanocomposites and their potential in chondrogenic tissue regeneration

The study was conducted to evaluate the cytocompatibility and hydrolytic degradability of the new poly(lactic acid)/polyethylene glycol-polyhedral oligomeric silsesquioxane (peg-POSS/PLLA) nanocomposite as potential material for cartilage regeneration. PLLA scaffolds containing 0 to 5% of peg-POSS were fabricated by electrospinning. Human mesenchymal stem cells (hMSC’s) were cultured in vitro to evaluate the cytocompatibility of the new nanocomposite material. Hydrolytic degradation studies were also carried out to analyze the mass loss rate of the nanocomposites through time. The addition of the peg-POSS to the PLLA did not affect the processability of the nanocomposite by electrospinning. It was also observed that peg-POSS did not show any relevant change in fibers morphology, concluding that it was well dispersed. However, addition of peg-POSS caused noticeable decrease in mean fiber diameter, which made the specific surface area of the scaffold to rise. hMSC’s were able to attach, to proliferate, and to differentiate into chondrocytes in a similar way onto the different types of electrospun peg-POSS/PLLA and pure PLLA scaffolds, showing that the peg-POSS as nano-additive does not exhibit any cytotoxicity. The hydrolytic degradation rate of the material was lower when peg-POSS was added, showing a higher durability of the nanocomposites through time. Results demonstrate that the addition of peg-POSS to the PLLA scaffolds does not affect its cytocompatibility to obtain hyaline cartilage from hMSC’s.

Electrospun nanofibrous scaffolds of poly (l-lactic acid)-dicalcium silicate composite via ultrasonic-aging technique for bone regeneration

Polymeric nanofibrous composite scaffolds incorporating bioglass and bioceramics have been increasingly promising for bone tissue engineering. In the present study, electrospun poly (l-lactic acid) (PLLA) scaffolds containing dicalcium silicate (C2S) nanoparticles (approximately 300nm) were fabricated. Using a novel ultrasonic dispersion and aging method, uniform C2S nanoparticles were prepared and they were homogenously distributed in the PLLA nanofibers upon electrospinning. In vitro, the PLLA-C2S fibers induced the formation of HAp on the surface when immersed in simulated body fluid (SBF). During culture, the osteoblastic MC3T3-E1 cells adhered well on PLLA-C2S scaffolds, as evidenced by the well-defined actin stress fibers and well-spreading morphology. Further, compared to pure PLLA scaffolds without C2S, PLLA-C2S scaffolds markedly promoted the proliferation of MC3T3-E1 cells as well as their osteogenic differentiation, which was characterized by the enhanced alkaline phosphatase (ALP) activity. Together, findings from this study clearly demonstrated that PLLA-C2S composite scaffold may function as an ideal candidate for bone tissue engineering.

A study on the in vitro degradation of poly(l-lactide)/chitosan microspheres scaffolds

Recent research shows that the addition of chitosan microspheres (CMs) to poly(l-lactide) (PLLA) can result in a composite scaffold material with improved biocompatibility and mechanical properties for tissue engineering applications. However, research regarding the influence of CMs on scaffold degradation is absent in the literature. This paper presents a study on the in vitro degradation of scaffolds made from PLLA with CMs. In this study, the PLLA/CMs scaffolds with a 25% ratio of CMs to PLLA were immersed in phosphate-buffered saline (PBS) solution at 37°C for 8 weeks. The in vitro degradation of the scaffolds was investigated using microcomputed tomography (μCT), weight loss analysis, Raman spectroscopy, and differential scanning calorimetry (DSC). Microstructure changes during degradation were monitored using μCT. The μCT results were consistent with the results obtained from Raman spectra and DSC analysis, which reflected that adding CMs into PLLA can decrease the degradation rate compared with pure PLLA scaffolds. The results suggest that PLLA/CMs scaffold degradation can be regulated and controlled to meet requirements imposed a given tissue engineering application.

STRUCTURAL FEATURES AND MECHANICAL PROPERTIES OF PLLA/PEARL POWDER SCAFFOLDS

In order to improve the mechanical properties of scaffolds for bone tissue engineering, the present study aims to bring calcium carbonate (CaCO3) with signaling molecules, namely pearl powder, into poly(L-lactic acid) (PLLA). PLLA/aragonite and PLLA/vaterite scaffolds were successfully fabricated by the freeze-drying method. Both composite scaffolds had a similar porous structure but a different saturated content of pearl powders. For both scaffolds, the porosity decreases and yield strength increases as pearl powder content increases. Introducing pearl powders into PLLA can improve the mechanical properties of the scaffolds. The porous structure plays a crucial role in the yield strength of pure PLLA scaffolds, whereas the yield strength of PLLA/pearl powder scaffolds mostly relies on pearl powder content.

Fibrin coating on poly (L-lactide) scaffolds for tissue engineering

A hybrid scaffold was obtained by the deposition of a thin network of submicron fibrin fibrils on the microporous walls of a macroporous poly(L-lactide) (PLLA) three-dimensional structure. The fibrin coating is homogeneous across the entire substrate and allowed the pore structure remain open in the hybrid scaffold. The elastic modulus of the hybrid scaffold (0.65 MPa) was increased up to twofold compared to the pure PLLA scaffold (0.29 MPa). Mouse pre-osteoblastic cells, MC3T3, were seeded on both pure PLLA and hybrid scaffolds, and cultured for 3, 6, and 24 h. The coating enhanced the cell colonization and proliferation and provided a more homogeneous distribution of cells within the scaffolds. In addition, the coating improved the scaffold adhesion properties by supplying new binding sites to the cells that modify the transmembrane receptors involved in initial cell adhesion mechanism. The expression of the β3 integrin was observed in cells cultured on fibrin-coated scaffolds instead of the α5 integrin, which was expressed in the uncoated scaffold. These hybrid PLLA/fibrin scaffolds have cell culture features suitable to promote early tissue regeneration.

Fabrication of macroporous chitosan/poly(l-lactide) hybrid scaffolds by sodium acetate particulate-leaching method

For tissue engineering applications, 3-D macroporous chitosan/poly(l-lactide) (PLLA) scaffolds were prepared by the particulate-leaching method using sodium acetate as the porogen in an acidic water/dioxane solution. The stability and dispersity of chitosan on the chitosan/PLLA hybrid scaffolds were determined by measuring water contact angles, establishing crystallinity using X-ray diffraction, and using eosin staining to observe the chitosan under a light microscope. The porous structure of the particulate-leached chitosan/PLLA scaffolds was investigated in terms of pore morphology, interconnectivity, etc. by using scanning electron microscopy. Chitosan/PLLA scaffolds produced by particulate-leaching showed a highly porous structure and improved stability and dispersity of chitosan as compared to pure PLLA and chitosan-coated PLLA scaffolds. The highly porous structure that resulted from a high concentration of chitosan improved the efficiency of cell adhesion after culturing cells for 4 h. After 48 h, the cultured cells showed increased cell proliferation on the hybrid scaffolds. Thus, particulate-leached chitosan/PLLA scaffolds can be applied to tissue engineering of various types, including the industrial membrane field.

In vitro cell performance on hydroxyapatite particles/poly( l-lactic acid) nanofibrous scaffolds with an excellent particle along nanofiber orientation

Highly porous hydroxyapatite (HA)/poly( l-lactide) (PLLA) nanofibrous scaffolds were prepared by incorporating needle-shaped nano- or micro-sized HA particles into PLLA nanofibers using electrospinning. The scaffolds had random or aligned fibrous assemblies and both types of HA particles were perfectly oriented along the fiber long axes. The biocompatibility and cell signaling properties of these scaffolds were evaluated by in vitro culture of rat osteosarcoma ROS17/2.8 cells on the scaffold surface. Cell morphology, viability and alkaline phosphatase (ALP) activity on each scaffold were examined at different time points. The HA/PLLA scaffolds exhibited higher cell viability and ALP activity than a pure PLLA scaffold. In addition, micro-sized HA particles supported cell proliferation and differentiation better than nano-sized ones in random scaffolds through a 10 day culture period and in aligned scaffolds at an early culture stage. The fibrous assembly of the scaffold had a pronounced impact on the morphology of the cells in direct contact with the scaffold surface, but not on cell proliferation and differentiation. Thus, HA/PLLA nanofibrous scaffolds could be good candidates for bone tissue engineering.

Mesoporous bioactive glass-coated poly(l-lactic acid) scaffolds: a sustained antibioticdrug release system for bone repairing

A hierarchically porous composite with mesoporous bioactive glasses (MBG) coated on macroporous poly(L-lactic acid) (PLLA) scaffolds has been prepared through a dip-coating process of PLLA into MBG sol solution and used as an antibiotic drug carrier. Characterization of the structure and morphology of the composite scaffolds indicated a stable and homogenous MBG deposition throughout the porous framework of the scaffolds. In vitro studies in simulated body fluid (SBF) showed great improvements of the hydrophilicity, bioactivity, and biodegradability if compared with pure PLLA scaffolds. As a result, the MBG coating promoted attachment, spreading and proliferation of rabbit bone marrow stromal cells (rBMSCs). Gentamicin sulfate (GS) was loaded into the composite system and showed a two-stage sustained release profile, which demonstrated satisfactory antibacterial properties.

Cell adhesive and growth behavior on electrospun nanofibrous scaffolds by designed multifunctional composites

Nanostructured biocomposite scaffolds of poly(l-lactide) (PLLA) blended with collagen (coll) or hydroxyapatite (HA), or both for tissue engineering application, were fabricated by electrospinning. The electrospun scaffolds were characterized for the morphology, chemical and tensile properties by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), water contact angle (WCA), Fourier transform infrared (FTIR) measurement, and tensile testing. Electrospun biocomposite scaffolds of PLLA and collagen or (and) HA in the diameter range of 200–700nm mimic the nanoscale structure of the extracellular matrix (ECM) with a well-interconnection pore network structure. The presence of collagen in the scaffolds increased their hydrophility, and enhanced cell attachment and proliferation, while HA improved the tensile properties of the scaffolds. The biocompatibility of the electrospun scaffolds and the viability of contacting cells were evaluated by 4′,6-diamidino-2-phenylindole dihydrochloride (DAPI) nuclear staining and by fluorescein diacetate (FDA) and propidium iodide (PI) double staining methods. The results support the conclusion that 293T cells grew well on composite scaffolds. Compared with pure PLLA scaffolds a greater density of viable cells was seen on the composites, especially the PLLA/HA/collagen scaffolds.

Fabrication and characterization of nano composite scaffold of poly(l-lactic acid)/hydroxyapatite

To mimic the nano-fibrous structure of the natural extracellular matrix, a nano composite scaffold of poly(L-lactic acid)/hydroxyapatite(PLLA/HAP) was fabricated by a thermally induced phase separation method. The characterization of the composite scaffold showed that the scaffold had a nano-fibrous PLLA network (fiber size 100-750 nm), an interconnective microporous structure (1-10 microm) and high porosity (>90%). HAP was homogeneously distributed in the scaffold, as a result, the compressive modulus of PLLA/HAP (80:20, w/w) increased to 3.15-fold compared with that of a pure PLLA scaffold. Incorporating HAP into PLLA network also buffered the pH decline in vitro degradation and enhanced the protein adsorption of the composite scaffold significantly. The new nano composite scaffold is potentially a very promising scaffold for tissue engineering.

Fabrication of Nano-fibrous PLLA Scaffold Reinforced with Chitosan Fibers

In this study, a nano-fibrous PLLA scaffold reinforced by micro-scale chitosan fibers was fabricated using thermally-induced phase separation (TIPS). The morphology, porosity, mechanical performance and pH changes in in vitro degradation of the scaffold were also investigated. Results showed that the mechanical properties of the scaffold increased with the amount of chitosan fibers embedded, and the pH in in vitro degradation of the scaffold changed more slowly than that of the pure nano-fibrous PLLA scaffold without chitosan fibers. The new composite scaffold might be a very promising scaffold for tissue engineering.

Needle-like nano hydroxyapatite/poly( l-lactide acid) composite scaffold for bone tissue engineering application

In this paper, a new nano-hydroxyapatite / poly ( l-lactide acid) (nHAP/PLLA) composite scaffold comprising needle-like nHAP particles was prepared. In the first step, the identification and morphology of chemically synthesized HAP particles were determined by XRD, EDX, FTIR and SEM analyses. The needle-like nHAP particles with an average size of approximately 30–60 nm in width and 100–400 nm in length were found similar to needle-like bone nano apatites in terms of chemical composition and morphology. In the second step, nHAP and micro-sized HAP (mHAP) particles were used to fabricate HAP filled PLLA (HAP/PLLA) composites scaffolds using solid–liquid phase separation method. The porosity of scaffolds was up to 85%, and their average macropore diameter was in the range of 64–175 µm. FTIR and XRD analyses showed the presence of molecular interactions and chemical linkages between HAP particles and PLLA matrix. The compressive strength of nanocomposite scaffolds could high up to 8.46 MPa while those of pure PLLA and microcomposite scaffolds were 1.79 and 4.61 MPa, respectively. The cell affinity and cytocompatibility of the nanocomposite scaffold were found to be higher than those of pure PLLA and microcomposite scaffolds. Based on the results, the newly developed nHAP/PLLA composite scaffold is comparable with cancellous bone in terms of microstructure and mechanical strength, so it may be a suitable alternative for bone tissue engineering applications.

Synthesis and characterization of nano-hydroxyapatite rods/poly(l-lactide acid) composite scaffolds for bone tissue engineering

The aims of this work were synthesis of rod shaped nano-hydroxyapatite (nHAP) and fabrication of novel nano-hydroxyapatite/poly(l-lactide acid) (nHAP/PLLA) composite scaffold. In the first step, the identification and morphology of chemically synthesized nHAP particles were determined by XRD, EDX, FTIR and SEM analyses. The rod shaped nHAP particles with an average size of approximately 37–65 nm in width and 100–400 nm in length were found similar to natural bone apatite in terms of chemical composition and structural morphology. In the second step, nHAP and micro sized HAP (mHAP) particles were used to fabricate HAP filled PLLA (HAP/PLLA) composites scaffolds using thermally induced phase separation method. The porosity of scaffolds was up to 85.06% and their average macropore diameter was in the range of 64–175 μm. FTIR and XRD analyses showed some molecular interactions and chemical linkages between HAP particles and PLLA matrix. The compressive strength of nanocomposite scaffolds could high up to 14.9 MPa while those of pure PLLA and microcomposite scaffolds were 1.79 and 13.68 MPa, respectively. The cell affinity and biocompatibility of the nanocomposite scaffold were found to be higher than those of pure PLLA and microcomposite scaffolds. Following the results, the newly developed nHAP/PLLA composite scaffold is comparable with cancellous bone in terms of microstructure and mechanical strength, so it may be considered for bone tissue engineering applications.

Surface modification of bioactive glass nanoparticles and the mechanical and biological properties of poly( l-lactide) composites

Novel bioactive glass (BG) nanoparticles/poly( l-lactide) (PLLA) composites were prepared as promising bone-repairing materials. The BG nanoparticles (Si:P:Ca = 29:13:58 weight ratio) of about 40 nm diameter were prepared via the sol–gel method. In order to improve the phase compatibility between the polymer and the inorganic phase, PLLA ( M n = 9700 Da) was linked to the surface of the BG particles by diisocyanate. The grafting ratio of PLLA was in the vicinity of 20 wt.%. The grafting modification could improve the tensile strength, tensile modulus and impact energy of the composites by increasing the phase compatibility. When the filler loading reached around 4 wt.%, the tensile strength of the composite increased from 56.7 to 69.2 MPa for the pure PLLA, and the impact strength energy increased from 15.8 to 18.0 kJ m −2. The morphology of the tensile fracture surface of the composite showed surface-grafted bioactive glass particles (g-BG) to be dispersed homogeneously in the PLLA matrix. An in vitro bioactivity test showed that, compared to pure PLLA scaffold, the BG/PLLA nanocomposite demonstrated a greater capability to induce the formation of an apatite layer on the scaffold surface. The results of marrow stromal cell culture revealed that the composites containing either BG or g-BG particles have much better biocompatibility compared to pure PLLA material.

Effect of Hydrolysis Pretreatment on the Formation of Bone-like Apatite on Poly(L-lactide) by Mineralization in Simulated Body Fluids

A bone-like apatite-coated surface that mediates a positive interaction between materials and bone is key to the development of desirable bone substitute materials. To incorporate apatite-coating on poly(L-lactide) (PLLA) surfaces, the effect of the hydrolysis of PLLA surfaces on the formation ability of bone-like apatite was investigated in this study.PLLA films and porous PLLA scaffolds were hydrolyzed for different time periods in alkaline solution and the hydrolyzed PLLA surfaces were characterized with X-ray photoelectron spectroscopy, atomic force microscopy, contact angle, and the measurement of carboxyl density. An apatite coating was formed by mineralizing the hydrolyzed PLLA in simulated body fluids (SBF) for 3 weeks and characterized. The hydrolyzed PLLA surfaces were rich in COOH and OH; the hydrophilicity, surface roughness, and carboxyl density increased with the hydrolysis time. After the incubation in SBF, a bone-like apatite layer with different morphology and composition was formed on the PLLA surfaces. The apatite formation on PLLA surfaces was promoted by the hydrolysis pretreatment and this increases with hydrolysis time. In addition, the compression module of the apatite-coated PLLA scaffolds increased compared with the pure PLLA scaffolds and increased with the hydrolysis time. The hydrolysis pretreatment was important in functionalizing the PLLA surfaces, facilitating subsequent apatite nucleation and apatite growth.