Aug 2026· Medicine and ecology· pp. 136-145· 0 citations· 17 references
TL;DR
The obtained results confirm the potential of PLA-based composites modified with hydroxyapatite and gentamicin as functional biodegradable materials for implant applications in regions with moderate mechanical loading, combining mechanical support, bioactivity, and local antimicrobial protection.
Abstract
Aim.
Development and experimental characterization of a bioactive composite based on polylactic acid, modified with hydroxyapatite and gentamicin, for implant applications.
Materials and methods.
PLA-based composites were prepared by solution mixing followed by hot pressing, with variation of the hydroxyapatite content (0 40 wt. %). The microstructure and distribution of the inorganic filler were analyzed using scanning electron microscopy and energy-dispersive X-ray analysis. Mechanical properties were evaluated by three-point bending tests with determination of flexural strength and Young’s modulus in accordance with ISO 178:2019. Antimicrobial activity was assessed in vitro by the agar diffusion method against standard test strains of
Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa,
and
Candida albicans.
Results and discussion.
The developed composite fabrication approach was shown to provide a homogeneous microstructure with a dispersed distribution of hydroxyapatite within the polymer matrix without pronounced macro-agglomeration. An increase in hydroxyapatite content resulted in a systematic decrease in flexural strength accompanied by a moderate increase in Young’s modulus, reflecting the trade-off between stiffness and resistance to bending deformations characteristic of particulate-filled polymer systems. Gentamicin-containing composites exhibited pronounced antimicrobial activity against Gram-positive and Gram-negative bacteria.
Conclusions.
The obtained results confirm the potential of PLA-based composites modified with hydroxyapatite and gentamicin as functional biodegradable materials for implant applications in regions with moderate mechanical loading, combining mechanical support, bioactivity, and local antimicrobial protection.
Controlled drug delivery systems have been developed to overcome the challenges associated with conventional delivery systems. Among all drug carriers, hydrogels are considered one of the most promising due to their ease of fabrication and their structural similarity to the body’s extracellular matrix. In this work, a sodium alginate/gelatin (Alg/Gel)-based hydrogel composite system was developed by incorporating hydroxyapatite (HA) and monetite (Mon) as fillers to improve its biological and mechanical properties. A comparative analysis of both composites was performed to evaluate the pH-dependent drug release of ciprofloxacin (CP). The characterization of the prepared composite was performed using Fourier transform infrared spectroscopy, which confirmed that the presence of physical and non-covalent interactions within the composite. Scanning electron microscopy (SEM) analysis of the prepared composites showed that the pristine hydrogel membrane surface was smooth, while the surface roughness increased with increasing filler concentration. A significant improvement in mechanical strength, hydrophilicity, and swelling ability was observed after the addition of HA and Mon to the Alg/Gel system. Both composite systems showed a slow and gradual release of the drug at different pH values (2, 7.4, and 10). The two polymer composites (Alg/Gel/HA/100 mg CP and Alg/Gel/Mon/100 mg CP) exhibited almost the same percentage drug release at pH 2 (acidic) and pH 10 (alkaline). However, Alg/Gel/HA/100 mg CP has the highest percentage drug release at pH 7.4 (physiological). The results suggest that the prepared hydrogel system could be used for a gradual, pH-dependent drug delivery.
Muzamil Ahmad Khan, Sadaf Batool, Saad Asim et al.· Materials Research Express· 0 citations
Bioactive strength is crucial for load-bearing biomaterials. Although hydroxyapatite is highly biocompatible, it has brittleness and a lack of dual-ion substitution in polymeric scaffold studies. In this work, Ce/Fe doped HAP was synthesized by chemical precipitation and solvent cast onto PLA films. Phase-pure HAP with no secondary phases and a crystallite size decrease from 2.58-0.85 nm following doping was confirmed by XRD. Its structural integrity was confirmed by FTIR, which showed the distinctive phosphate and hydroxyl bands 550-627, 964.7, 1026, 3441 and 650 cm-1. While EDAX confirmed the distribution of Ca, P, Ce and Fe with Ca/P ratios between 1.64 and 1.67. SEM showed homogeneous morphology. Nanorod structures measuring roughly 50-100 nm in length and 15-20 nm in width were revealed by TEM investigation. Enhanced surface reactivity was indicated by a rise in BET surface area from 89.17-105.82 m2/g and pore-volume from 0.411-0.499 cm3/g. Rapid apatite-nucleation and thick Ca/P-rich layer development were encouraged by in vitro bioactivity in SBF. Because enhanced dispersion stability and decreased particle agglomeration promote cellular interaction and lessen harmful effects, DLS analysis revealed nanosized with stable zeta potential, which correlates with the reported MG-63 cell viability reaching 84%. Excellent hemocompatibility was demonstrated by the fabricated dual ion doped HAP/PLA composite. Microhardness improved by almost 85%, rising from 73 HV to 135 HV. Ce/Fe doped HAP sample possess superior anti-microbial efficiency against both gram (+)'ve and gram (-)'ve strains. These findings demonstrate the complementary effects of polymer reinforcement and dual-ion doping, suggesting great promise for Osteo-regenerative applications.
Sabitha R, Kumaraguru S, Issathul Riswan M et al.· Journal of Biomaterials Scie...· 0 citations
This study develops an industrially applicable composite by combining polylactic acid (PLA) with chitosan (CS) for antimicrobial properties and microcrystalline cellulose (MCC) for enhanced mechanical performance. Mechanical behaviour, microstructure, and morphology were analysed using tensile tests, scanning electron microscopy (SEM), and X‐ray diffraction (XRD). Antibacterial activity was evaluated against Gram‐positive and Gram‐negative bacteria. The samples were prepared by heating thermoplastic polylactic acid (PLA) and subsequently molding them into test specimens in accordance with ASTM D638. Results showed that adding MCC increased tensile strength and modulus, with the highest values in PLA (A) containing 2% MCC and 2% CS. Higher MCC content caused agglomeration, reducing mechanical properties. SEM and XRD revealed that MCC increased crystallinity, while CS decreased it. PLA/MCC/CS composites demonstrated stronger antibacterial activity than pure PLA. The findings indicate that the composites offer both improved mechanical properties and enhanced antibacterial function, making them promising for biomedical applications. Further optimization is needed to improve interfacial adhesion and reinforcement dispersion.
Ivan Antônio, Natalia Suseno, E. Savitri et al.· Macromolecular Symposia· 0 citations
The bamboo shell-derived HAp/Alg composite produced at pH 10 was a potential candidate for localized antibacterial drug delivery systems in biomedical applications and carried clindamycin efficiently carried on the composite matrix and released in a sustained manner.
Wulandari Wulandari, N. Jamarun, D. V. Wellia et al.· Baghdad Science Journal· 0 citations
Processing methods strongly influence the degradation behaviour of semi-crystalline polylactic acid (PLA) by affecting its molecular orientation, crystallinity, and micro-and macrostructural features. In our previous study, we presented the changes in the properties of the electrospun PLA fibers during in vitro degradation. Building on these findings, this study compares the degradation of PLA specimens prepared using two bulk processing methods: (i) fused filament fabrication (FFF) 3D printing and (ii) film extrusion. Specimens were incubated in phosphate-buffered saline (pH 7.4) at 37 °C for 1, 3, 7, 28, and 56 days. At each time point, degradation was assessed by tensile testing, differential scanning calorimetry, and weight retention analysis. PLA films exhibited an initial decrease in Young’s modulus, followed by a temporary increase and subsequent decline, whereas FFF specimens maintained mechanical stability for several days before a gradual deterioration. Both specimens showed reduced crystallinity over time, with FFF samples becoming fully amorphous by day 56. Minimal weight change (<1%) indicated that degradation proceeded primarily through structural and morphological changes rather than bulk erosion. Overall, 3D-printed PLA exhibited more stable mechanical properties than extruded PLA films. These findings highlight the significant impact of the processing route on PLA degradation, guiding the optimization of PLA performance in biomedical, packaging, and sustainable material applications.
Hydroxyapatite (HA) is widely used in biomedical applications due to its biocompatibility and chemical similarity to the mineral phase of bone; however, its low mechanical strength limits its structural use. In this work, HA ceramics with different Mg additions (0, 0.5, 1, 3, 5, and 10% by weight) were prepared using the powder processing technique. The mixtures were homogenized, conformed and sintered at 1100 °C. The incorporation of intermediate Mg concentrations produced an increase in fracture toughness compared to pure HA. The best mechanical performance was obtained with the formulation containing 5% Mg by weight, achieving a hardness of 319 HV, a porosity of 12.92% and a fracture toughness of 4.06 MPa·m0.5, comparable to those reported for human cortical bone, indicating its potential for applications in moderately loaded bone implants. The findings indicate that magnesium functions as a reinforcing component in the ceramic matrix, mitigating critical defects and thereby contributing to the improved toughness of Mg-containing hydroxyapatite ceramics. The polarization resistance results show that the incorporation of low fractions by weight of magnesium (1% Mg) adjusts the electrochemical behavior of the material, while higher increases in its concentration cause a deterioration of this property.
Elizabeth Refugio-García, Z. I. Bedolla-Valdez, Alfredo Emiliano Chávez-Pantiga et al.· Applied Biosciences· 0 citations