Borate Bioactive Glass Research Articles

Cobalt-containing borate bioactive glass fibers for treatment of diabetic wound

Impaired angiogenesis is one of the predominant reasons for non-healing diabetic wounds. Cobalt is well known for its capacity to induce angiogenesis by stabilizing hypoxia-inducible factor-1α (HIF-1α) and subsequently inducing the production of vascular endothelial growth factor (VEGF). In this study, Co-containing borate bioactive glasses and their derived fibers were fabricated by partially replacing CaO in 1393B3 borate glass with CoO. Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) analyses were performed to characterize the effect of Co incorporation on the glass structure, and the results showed that the substitution promoted the transformation of [BO3] into [BO4] units, which endow the glass with higher chemical durability and lower reaction rate with the simulated body fluid (SBF), thereby achieving sustained and controlled Co2+ ion release. In vitro biological assays were performed to assess the angiogenic potential of the Co-containing borate glass fibers. It was found that the released Co2+ ion significantly enhanced the proliferation, migration and tube formation of the Human Umbilical Vein Endothelial Cells (HUVECs) by upregulating the expression of angiogenesis-related proteins such as HIF-1α and VEGF. Finally. In vivo results demonstrated that the Co-containing fibers accelerated full-thickness skin wound healing in streptozotocin (STZ)-induced diabetic rat model by promoting angiogenesis and re-epithelialization.Graphical

3D-printed hydrogels dressings with bioactive borate glass for continuous hydration and treatment of second-degree burns.

Recent advances in additive manufacturing have led to the development of innovative solutions for tissue regeneration. Hydrogel materials have gained significant attention for burn wound treatment in clinical practice among various advanced dressings due to their soothing and moisturizing activity. However, prolonged healing, pain, and traumatic removal due to the lack of long-term wound hydration are some of the challenges in the treatment of second-degree burn wounds. In this study, 3D-printed dressings were fabricated using gelatin, alginate, and bioactive borate glass (BBG) using an extrusion-based bioprinter. After ionic crosslinking, the 3D-printed dressings were characterized for mechanical properties, degradation rate, hydration activity, and in vitro cell viability using human fibroblasts. The results demonstrated that in 3D-printed dressings with 20 wt% BBG, Young's modulus increased by 105%, and 10-day degradation rate decreased by 62%. Addition of BBG prevented the burst release of water from hydrogel dressings and enabled the continuous water release for up to 10 days, which is crucial in treating second-degree burn wounds. 3D-printed hydrogel dressings with BBG showed long-term cell viability that can be a result of the accumulative release of therapeutic ions from BBG particulate. The in vivo wound healing functionality of the dressings was investigated using a rat model with a second-degree burn wound. Our animal study showed that the 3D-printed dressings with BBG exhibited faster wound closure, non-adhesive contact, non-invasive debridement, and non-traumatic dressing removal. Histological analysis suggested that 3D-printed dressings contributed to more uniform re-epithelialization and tissue remodeling compared to the non-printed hydrogels of the same compositions. Critically, 3D-printed dressings with BBG led to significant regeneration of hair follicles compared to the 3D-printed hydrogel, non-printed hydrogel, and the control groups. The superior outcome of the 3D-printed hydrogel-BBG20 dressings can be attributed to the bioactive formulation, which promotes moist wound healing for longer time periods, and the non-adhesive porous texture of the 3D-printed dressings with increased wound-dressing interactions. Our findings provided proof of concept for the synergistic effect of bioactive formulation and the porous texture of the 3D-printed hydrogel dressings incorporated with BBG on continuous water release and, consequently, on second-degree burn wound healing.

Fabrication and in vitro studies on bioactive borate glasses containing dopant chromium sulfate

This research aims to assess the bioactive properties of the modified borate glasses containing extremely low concentrations (≤5 mol.%) from chromium sulfate (Cr2(SO4)3). The glasses in the system xCr2(SO4)3.(60–x)B2O3.15CaO.15Na2O.10P2O5, where x = 0, 1, 2, and 5 mol.% were prepared by the melt quenching technique. All glass samples have been treated thermally at 600 °C for 6 h. Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), and X-ray Diffraction (XRD) measurements were carried out to differentiate between the structural changes before and after soaking in the simulated body fluid (SBF) at about 37 °C for 1, 2, and 3 weeks. Glass-ceramic samples have showed sharper peaks that are identified using X-ray diffraction data. These crystalline phases are indexed to crystalline calcium borate (Ca2B2O3) and calcium phosphate (Ca3(PO4)2). In vitro tests, FTIR spectra revealed two small bands in the 560-610 cm−1 range which might be assigned to the formation of a hydroxyapatite layer (HA). The formation of HA was also confirmed by XRD results, particularly after immersion in SBF for 21 days. The study suggests that the presently studied glasses containing Cr2(SO4)3 can possess good bioactivity which might be considered to be suitable for some bio and medical applications.

From nanoscale to microscale hierarchical multifunctional nano borate bioactive glass for efficient wound healing

The unique biodegradation and mineralization properties of nanosized CO32−- containing hydroxyapatite (HCA)-coated BBG (nano-HCA@BG) make it a promising material for soft tissue repair. However, its single-function solid powder form makes it difficult to control drug release rates, limiting its potential in vivo application. To address this challenge, we designed a hierarchical multifunctional composite by incorporating gelatin with nano-HCA@BG loaded with AgNPs. The hierarchical composite achieved a high degree of structural fit from nanometer to micrometer scale, as demonstrated by structural characterization results. The composite showed improved encapsulation of nanodrug and controlled degradation, as confirmed by degradation and antimicrobial property results. Wound healing experiments in vivo revealed efficient encapsulation of nano-HCA@BG through specific combination of gelatin and nano-HCA@BG, leading to improved controlled degradation and biological activity of the glass. The study also developed a dynamic flowing drug loading method that integrated material preparation and drug loading, thus improving the efficiency of drug loading of the nano-HCA@BG. Overall, our study demonstrates a new method for the preparation of hierarchical functional biomaterials of bioglass, laying the foundation for nano-HCA@BG to play an important role in tissue repair. Moreover, our findings suggest that better understanding of the structure and biological properties of nano-HCA@BG could expand its application in other biomedical fields such as drug delivery.

A 3D-Printed Wound-Healing Material Composed of Alginate Dialdehyde-Gelatin Incorporating Astaxanthin and Borate Bioactive Glass Microparticles.

In this study, a wound dressing composed of an alginate dialdehyde-gelatin (ADA-GEL) hydrogel incorporated by astaxanthin (ASX) and 70B (70:30 B2O3/CaO in mol %) borate bioactive glass (BBG) microparticles was developed through 3D printing. ASX and BBG particles stiffened the composite hydrogel construct and delayed its in vitro degradation compared to the pristine hydrogel construct, mainly due to their cross-linking role, likely arising from hydrogen bonding between the ASX/BBG particles and ADA-GEL chains. Additionally, the composite hydrogel construct could hold and deliver ASX steadily. The composite hydrogel constructs codelivered biologically active ions (Ca and B) and ASX, which should lead to a faster, more effective wound-healing process. As shown through in vitro tests, the ASX-containing composite hydrogel promoted fibroblast (NIH 3T3) cell adhesion, proliferation, and vascular endothelial growth factor expression, as well as keratinocyte (HaCaT) migration, thanks to the antioxidant activity of ASX, the release of cell-supportive Ca2+ and B3+ ions, and the biocompatibility of ADA-GEL. Taken together, the results show that the ADA-GEL/BBG/ASX composite is an attractive biomaterial to develop multipurposed wound-healing constructs through 3D printing.

Structural, optical, and cytotoxicity studies of laser irradiated ZnO doped borate bioactive glasses

Borate glasses (BG) doped with different amounts of ZnO (0–0.6 mol%) were formed by the traditional melt quenching technique. The different glasses so made were characterized using different characterization techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and UV–Vis absorption optical properties. The XRD patterns showed an amorphous structure with one broad peak at 2θ = 29°, while the phonons bands were studied in terms of the FTIR bands. Optical properties of the glasses were studied using UV–Vis absorption spectra in the range 190–1100 nm, in which the prominent band lies at about 261.5 nm of peak position, from which the bandgab (Eg) was calculated from its edge using Tauc’s plot, with Eg ~ 3.5 eV. The laser irradiation showed no significant changes in the absorption bands, despite a significant change observed in the amorphous behavior in the XRD pattern. The cell viability was performed for two samples of the BG and 0.6 mol% ZnO doped using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay method. The result showed better cell viability and low toxicity. So, ZnO doped BG can be used in various biomedical applications.

The angiogenic potential of pH-neutral borophosphate bioactive glasses.

Borate bioactive glasses have gained attention in recent years due to their therapeutic and regenerative effects in vivo. However, borate bioactive glasses release alkaline ions, increasing the local pH and creating a toxic environment for cell culture studies. A partial compositional substitution of phosphate for borate can create a pH-neutral glass that does not significantly affect the local pH while still releasing therapeutic ions. In the present study, a series of Na-Ca-borophosphate bioactive glasses with different borate-to-phosphate ratios was evaluated in vitro and in vivo for cytotoxicity and angiogenic effects. Compared to more basic borate glasses, the pH-neutral glasses supported endothelial cell migration and stimulated greater blood vessel formation in a chick chorioallantoic membrane model. The results from this study indicate that these pH-neutral glasses are promising angiogenic biomaterials for use in tissue engineering and regenerative medicine.

Two-dimensional molybdenum disulfide/polymer-coated bioactive glass scaffolds for tissue engineering: Fabrication, structural, mechanical, bioactivity, and radiation interaction properties

Molybdenum disulfide (MoS2)-based nanostructures are widely used in environmental protection and biomedicine owing to their biological, physical, chemical, electrical, and mechanical properties. In this study, polycaprolactone (PCL)- and polylactide-co-glycolide (PLGA)-coated bioactive glass scaffolds containing MoS2 nanoparticles are prepared, and their usability in bone tissue engineering applications is evaluated. Borate bioactive glass scaffolds are fabricated using the replication method and coated with PCL or PLGA solutions (5 wt%) containing MoS2 (0.1, 0.2, 0.5, 1, and 2 wt%) nanoparticles. The structural and mechanical properties of the scaffolds and their bioactivity in simulated body fluids are investigated comprehensively. The ionization–radiation-shielding properties are investigated using Monte Carlo simulations. The results show that the polymer coating layer and presence of MoS2 nanoparticles in the polymer matrix improves the mechanical properties of the scaffolds. The addition of MoS2 nanoparticles to the structure increases the hydroxyapatite-forming ability of bioactive glass-based composites. Additionally, the prepared composite scaffolds exhibit high radiation-shielding ability owing to the presence of MoS2 nanoparticles embedded in the polymer matrix that shields the glass surface. Bioactive glass composite scaffolds containing MoS2 nanoparticles demonstrate promising potential for bone regeneration and radiation-shielding applications.

Zinc- and Copper-Doped Mesoporous Borate Bioactive Glasses: Promising Additives for Potential Use in Skin Wound Healing Applications.

In this study, zinc (Zn)- and copper (Cu)-doped 13-93B3 borate mesoporous bioactive glasses (MBGs) were successfully synthesized using nitrate precursors in the presence of Pluronic P123. We benefited from computational approaches for predicting and confirming the experimental findings. The changes in the dynamic surface tension (SFT) of simulated body fluid (SBF) were investigated using the Du Noüy ring method to shed light on the mineralization process of hydroxyapatite (HAp) on the glass surface. The obtained MBGs were in a glassy state before incubation in SBF. The formation of an apatite-like layer on the SBF-incubated borate glasses was investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The incorporation of Zn and Cu into the basic composition of 13-93B3 glass led to changes in the glass transition temperature (Tg) (773 to 556 °C), particle size (373 to 64 nm), zeta potential (-12 to -26 mV), and specific surface area (SBET) (54 to 123 m2/g). Based on the K-means algorithm and chi-square automatic interaction detection (CHAID) tree, we found that the SFT of SBF is an important factor for the prediction and confirmation of the HAp mineralization process on the glasses. Furthermore, we proposed a simple calculation, based on SFT variation, to quantify the bioactivity of MBGs. The doped and dopant-free borate MBGs could enhance the proliferation of mouse fibroblast L929 cells at a concentration of 0.5 mg/mL. These glasses also induced very low hemolysis (<5%), confirming good compatibility with red blood cells. The results of the antibacterial test revealed that all the samples could significantly decrease the viability of Pseudomonas aeruginosa. In summary, we showed that Cu-/Zn-doped borate MBGs can be fabricated using a cost-effective method and also show promise for wound healing/skin tissue engineering applications, as especially supported by the cell test with fibroblasts, good compatibility with blood, and antibacterial properties.

Mechanistic study of the bioactivity improvement of Al2O3-doped BBG after dynamic flow treatment

A simple and effective method for improving the biological activity of borate bioactive glass (BBG) is to perform dynamic flow treatment with simulated body fluid (SBF). The phosphate layer formed on the BBG surface during flow treatment enhances the biocompatibility of this bioglass. However, the micromechanism of the formation of highly bioactive mineralized products on the surface of BBG under dynamic flow treatment is not clearly understood. In this study, we investigated the effect of dynamic flow treatment on the biological properties of Al 2 O 3 -doped BBG. The results revealed that the SBF-treated Al 2 O 3 -doped BBG exhibits significantly reduced degradation rate and improved bioactivity. The characterization of the treated Al 2 O 3 -doped BBG by Fourier-transform infrared and solid-state NMR spectroscopies revealed that Al mainly exists in the form of four-coordinated aluminum in BBG. During the dynamic flow treatment process, four-coordinated aluminum transforms into six-coordinated aluminum, which chemically interacts with PO 4 3− to improve the biological activity of Al-BBG. In addition, the much more phosphate deposited on BBG sample containing less Al 2 O 3 and promote hydroxyapatite formation on the glass surface. In vitro cell studies suggested that the Al 2 O 3 -doped BBG after treated by dynamic flow treatment boosts the proliferation of MC-3T3E1. This work demonstrates that dynamic flow treatment is a simple and effective method for improving the bioactivity of BBG and also expands our understanding of the micromechanics of the degradation and biomineralization of Al 2 O 3 -doped BBG.

A review on borate bioactive glasses (BBG): effect of doping elements, degradation, and applications.

Because of their excellent biologically active qualities, bioactive glasses (BGs) have been extensively used in the biomedical domain, leading to better tissue-implant interactions and promoting bone regeneration and wound healing. Aside from having attractive characteristics, BGs are appealing as a porous scaffold material. On the other hand, such porous scaffolds should enable tissue proliferation and integration with the natural bone and neighboring soft tissues and degrade at a rate that allows for new bone development while preventing bacterial colonization. Therefore, researchers have recently become interested in a different BG composition based on borate (B2O3) rather than silicate (SiO2). Furthermore, apatite synthesis in the borate-based bioactive glass (BBG) is faster than in the silicate-based bioactive glass, which slowly transforms to hydroxyapatite. This low chemical durability of BBG indicates a fast degradation process, which has become a concern for their utilization in biological and biomedical applications. To address these shortcomings, glass network modifiers, active ions, and other materials can be combined with BBG to improve the bioactivity, mechanical, and regenerative properties, including its degradation potential. To this end, this review article will highlight the details of BBGs, including their structure, properties, and medical applications, such as bone regeneration, wound care, and dental/bone implant coatings. Furthermore, the mechanism of BBG surface reaction kinetics and the role of doping ions in controlling the low chemical durability of BBG and its effects on osteogenesis and angiogenesis will be outlined.

Glycol thermal synthesis of the 45B5 bioactive borate glass: Structural, physical, and apatite mineralization in vitro

This work was performed aiming to develop a new and straightforward route for bioactive glasses obtention with minimal equipment and explore the structural, physical, and bioactivity properties of the resulting glass and its glass ceramics. Herein, the synthesis of the borate bioactive glass in the 45B5 composition (46.1 B2O3 – 26.9 CaO – 24.4 NaO – 2.6 P2O5, mol%) by the glycol thermal method was proposed; an original chemical route for bioactive glass obtention based on transesterification reaction between the precursors with a glycol. The suggested mechanism for the borate network formation was proven accurate, revealing a vitreous structure formed by ring-type metaborate structural units with a lamellar morphology upon calcination. Glass-ceramics obtained at 500 (45B5-500) and 700 °C (45B5-700) indicate the oxides were effectively incorporated into the network by crystallization of Ca–Na–B, Ca–B, and Na–B phases. The in vitro apatite mineralization assay performed on the glass and glass-ceramics revealed their great solubility and conversion rate into hydroxyapatite (HA, Ca5(PO4)3(OH)), which is taken as an indication of bioactivity. Besides HA, however, calcium carbonate species were identified at the early stages of mineralization for 45B5 and 45B5-500, suggesting the 45B5-700 glass-ceramic has a higher ability to form apatite as the majority of Ca2+ are directed to precipitate into hydroxyapatite. Overall, the 45B5 glass and glass-ceramics demonstrated their great bioactivity, having high application potential in soft tissue engineering on wound healing materials and devices, as incorporation in hydrogels and nanofibers. Furthermore, the glycol thermal method generated new perspectives for the synthesis of a broad range of bioactive glasses compositions and their application in tissue engineering.

Characterization of sodium and calcium addition on immediate aqueous interactions of binary borate glasses by dynamic vapour sorption with in-situ Raman

This study describes a novel technique; dynamic vapour sorption (DVS) with in-situ Raman spectroscopy, to investigate the reactivity and mechanisms of aqueous interactions of bioactive borate glasses (BGs). Two melt-derived binary-BGs; (70)B2O3-(30)Na2O and (70)B2O3-(30)CaO (mol%), were investigated to compare the effect of sodium and calcium addition on boron coordination and aqueous interactions, via DVS and dissolution in deionized water. DVS, which gravimetrically measures the effect of exposing BGs to a controlled relative humidity, was applied to quantitatively evaluate their glass-water reactivity. Meanwhile, in-situ Raman monitored structural changes in real-time to demonstrate their different aqueous reactions and characterize vapour- and water-induced crystallization of sodium-borate glasses. In conclusion, correlation of structural changes and reaction rates between vapour- and water-induced reactions validated the coupling of DVS and in-situ Raman as a more sensitive approach to characterize aqueous reactivity and reactions of BGs compared to traditional methods, such as submersion in aqueous solutions.

In-situ forming hydrogel based on thiolated chitosan/carboxymethyl cellulose (CMC) containing borate bioactive glass for wound healing

Suitable wound dressings for accelerating wound healing are actively being designed and synthesised. In this study, thiolated chitosan (tCh)/oxidized carboxymethyl cellulose (OCMC) hydrogel containing Cu-doped borate bioglass (BG) was developed as a wound dressing to improve wound healing in a full-thickness skin defect of mouse animal model. Thiolation was used to incorporate thiol groups into chitosan (Ch) to enhance its water solubility and mucoadhesion characteristics. Here, the in situ forming hydrogel was successfully developed using the Schiff-based reaction, and its physio-chemical and antibacterial characteristics were examined. Borate BG was also incorporated in the generated hydrogel to promote angiogenesis and tissue regeneration at the wound site. Investigations of in vitro cytotoxicity assays demonstrated that the synthesised hydrogels showed good biocompatibility and promoted cell growth. These results inspired us to investigate the effectiveness of skin wound healing in a mouse model. On the backs of animals, two full-thickness wounds were created and treated utilising two different treatment conditions: (1) OCMC/tCh hydrogel, (2) OCMC/tCh/borate BG, and (3) control defect. The wound closure ratio, collagen deposition, and angiogenesis activity were measured after 14 days to determine the healing efficacy of the in situ hydrogels used as wound dressings. Overall, the hydrogel containing borate BG was maintained in the defect site, healing efficiency was replicable, and wound healing was apparent. In conclusion, we found consistent angiogenesis, remodelling, and accelerated wound healing, which we propose may have beneficial effects on the repair of skin defects.

Modified Sol-Gel Synthesis of Mesoporous Borate Bioactive Glasses for Potential Use in Wound Healing.

In this study, we successfully utilized nitrate precursors for the synthesis of silver (Ag)-doped borate-based mesoporous bioactive glass (MBGs) based on the 1393B3 glass formulation in the presence of a polymeric substrate (polyvinyl alcohol (PVA)) as a stabilizer of boric acid. The X-ray diffraction (XRD) analysis confirmed the glassy state of all the MBGs. The incorporation of 7.5 mol% Ag into the glass composition led to a decrease in the glass transition temperature (Tg). Improvements in the particle size, zeta potential, surface roughness, and surface area values were observed in the Ag-doped MBGs. The MBGs (1 mg/mL) had no adverse effect on the viability of fibroblasts. In addition, Ag-doped MBGs exhibited potent antibacterial activity against gram-positive and gram-negative species. In summary, a modified sol–gel method was confirmed for producing the Ag-doped 1393B3 glasses, and the primary in vitro outcomes hold promise for conducting in vivo studies for managing burns.

The effect of borate bioactive glass ceramics containing silver nanoparticles on removal physiognomies of methylene blue

Several studies have been carried out with several materials on the removal of methylene blue from water. Well-known bioactive glass 46S5.2 was prepared by complete replacement of the silicate partner with boron oxide via a two-step crystallization process, in particular its glass-ceramic derivative. The characterization techniques for ceramic sample were performed such as Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive X-ray (EDX). Transmission electron microscope (TEM) was employed to ensure that silver addition reaches to the nanoscale. UV/Vis. optical absorption spectroscopy was utilized in the retracing process of methylene blue adsorption from its contaminated water. The antimicrobial activity of the prepared sample was also studied extensively. Also for the prepared glass-ceramic samples, the reusability test was carried out to ensure that they could be used more than once in water treatment applications.

Borate Bioactive Glasses (BBG): Bone Regeneration, Wound Healing Applications, and Future Directions.

Since the early 2000s, borate bioactive glasses (BBGs) have been extensively investigated for biomedical applications. The research so far indicates that BBGs frequently exhibit superior bioactivity and bone healing capacity compared to silicate glasses. They are also suitable candidates as drug delivery devices for infection or disease treatment such as osteoporosis. Additionally, BBGs are also an excellent option for wound healing applications, which includes the availability of commercial (FDA approved) microfibrous BBG dressings to treat chronic wounds. By addition of modifying ions, the bone or wound healing capacity of BBGs can be enhanced. For instance, addition of copper ions into BBGs was shown to drastically increase blood vessel formation for wound healing applications. Moreover, addition of ions such as magnesium, strontium, and cobalt improves bone healing. Other recent research interest related to BBGs is focused on nerve and muscle regeneration applications, while cartilage regeneration is also suggested as a potential application field for BBGs. BBGs are commonly produced by melt-quenching; however, sol–gel processing of BBGs is emerging and appears to be a promising alternative. In this review paper, the physical and biological characteristics of BBGs are analyzed based on the available literature, the applications of BBGs are discussed, and future research directions are suggested.

Inspection of Radiation Shielding Proficiency and Effect of Gamma-Ray on ESR and Thermal Characteristics of Copper Oxide Modified Borate Bioglasses

Samples of copper-modified bioactive borate glasses were synthesized and their radiation shielding properties including gamma-ray and neutron radiation shielding were investigated. Further, the glasses’ mass attenuation coefficients were measured with a NaI(Tl) detector while their gamma-ray shielding parameters were estimated using Phy-X/PSD program. Free-radical densities were measured via electron spin resonance to estimate the absorbed doses during accidental irradiation. The extensive reduction of the dose detection threshold (2 Gy) required the estimation of the signal of the non-irradiated sample. In addition, the effects of applied microwave power and absorbed dose on synthesized samples were studied. Finally, the thermal annealing of the emerging peaks, which were due to the irradiation signal-to-noise ratio and energy dependence, was studied to estimate the stabilities of such peaks. This modified material is recommended to detect and monitor the gamma-radiation dose because of its good dosimetric properties. Finally, regarding the presence of the two borate groups, triangular and the tetrahedrally coordinated, in their definite and typical wavenumbers, the FTIR spectra displayed simplified vibrations that were close to those of many bioglasses. This paper provides complementary results for the author's previous research examining this glass for low photon dose measurements using luminescence characteristics.

Hexagonal Boron Nitride/PCL/PLG Coatings on Borate Bioactive Glass Scaffolds for Bone Regeneration

Hexagonal Boron Nitride/PCL/PLG Coatings on Borate Bioactive Glass Scaffolds for Bone Regeneration

Effect of incorporation of piezoelectric phases on antibacterial and cellular response of borate bioactive glass

The present study investigates the consequences of incorporation (30 vol %) of piezoelectric Na0.5K0.5NbO3 (NKN) and BaTiO3 (BT) phases and surface polarization (20 kV at 500 °C) on in-vitro antibacterial and cellular response of borate bioactive glass (1393B3, BBG). XPS analyses elucidated that the surface chemistry of optimally processed composites remains unaffected after surface polarization treatment. The piezoelectric BT and NKN enhance the antibacterial activity of BBG by ∼ (53, 57%) and (51, 54%) for E. coli and S. aureus bacteria stains, respectively. The SEM images of bacteria, adhered on unpolarized and polarized surfaces demonstrate bacteria specific response. The combined action of piezoelectric phase and surface polarization increases the growth rate of osteoblast like MG-63 cells on negatively polarized BBG- BT (30 vol %) and BBG- NKN (30 vol%) composites by ∼ 76 and 82% respectively. Overall, the piezoelectric secondary phase incorporated in BBG as well as surface polarization increases the cellular and antibacterial response significantly.