Polymers, due to their high molecular weight, tunable architecture, functionality, and buffering ... more Polymers, due to their high molecular weight, tunable architecture, functionality, and buffering effect for endosomal escape, possess unique properties as a carrier or prophylactic agent in preventing pandemic outbreak of new viruses. Polymers are used as a carrier to reduce the minimum required dose, bioavailability, and therapeutic effectiveness of antiviral agents. Polymers are also used as multifunctional nanomaterials to, directly or indirectly, inhibit viral infections. Multifunctional polymers can interact directly with envelope glycoproteins on the viral surface to block fusion and entry of the virus in the host cell. Polymers can indirectly mobilize the immune system by activating macrophages and natural killer cells against the invading virus. This review covers natural and synthetic polymers that possess antiviral activity, their mechanism of action, and the effect of material properties like chemical composition, molecular weight, functional groups, and charge density on...
Background: For a new biomaterial which is going to be applied in bone tissue regeneration, bioac... more Background: For a new biomaterial which is going to be applied in bone tissue regeneration, bioactivity (bone bonding ability) and desirable mechanical properties are very essential parameters to take into consideration. In the present study, the gehlenite's mechanical properties and bioactivity are assessed and compared with hydroxyapatite (HA) for bone tissue regeneration. Method: Gehlenite and HA nanoparticles are synthesized through sol–gel method and coprecipitation technique, respectively, and their physical and chemical properties are characterized through X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy. Results: The results prove that the gehlenite and HA phases without any undesirable phase are obtained, and the particles of both compounds are in the nanometer range with spherical morphology. The compressive strength of both compounds are assessed, and the values for gehlenite and HA disks are 144 ± 5 and 150 ± 4.8 MPa, r...
Abstract In this study, a new nanocomposite scaffold entailing poly glycerol sebacate/polycaprola... more Abstract In this study, a new nanocomposite scaffold entailing poly glycerol sebacate/polycaprolactone/carbon quantum dots (PGS/PCL/CQDs) was designed and fabricated for cardiac muscle regeneration. The PGS/PCL fibrous scaffolds were electrospun in disparate weight ratios—2:1 and 1:1. Next, different amounts of CQDs (0.5 and 1 wt %) were incorporated in the PGS/PCL fibers to reach a ternary nanocomposite scaffold. Besides characterizing the physical and chemical properties of scaffolds—morphology, chemical bonds, mechanical properties, wettability, and electrical conductivity—the biological properties including cytotoxicity, cell attachment and proliferation, and degradation rate were assessed in vitro. To give proof of CQDs inclusion in the fibers, transmission electron microscopy and fluorescent assay were applied. Addition of both PGS and CQDs to the PCL fibers resulted in a significant decrease in the mean fiber diameter of ternary nanocomposite scaffold from 862 ± 167 down to 376.82 ± 150 nm. The electrical conductivity of scaffolds was increased through the incorporation of CQDs, whereas the addition of CQDs up to 1 wt % led to a decrease in the cell viability. According to the weight ratio optimization, the PGS/PCL/CQDs scaffold (2:1:0.5) outperformed the others in physical, chemical, and biological properties; the scaffold's Young's modulus, elongation at break, and ultimate tensile strength were 11 ± 1 MPa, 10 ± 1 mm, and 5 ± 1 MPa, respectively. Moreover, the cell viability of optimized nanocomposite scaffold was found to be very close to the negative control proving its desirable cell compatibility. Therefore, the optimized PGS/PCL/CQDs nanocomposite scaffold can be potentially promising for cardiac muscle tissue engineering.
Poly(2-hydroxyethyl methacrylate) (pHEMA) as a biomaterial with excellent biocompatibility and cy... more Poly(2-hydroxyethyl methacrylate) (pHEMA) as a biomaterial with excellent biocompatibility and cytocompatibility elicits a minimal immunological response from host tissue making it desirable for different biomedical applications. This article seeks to provide an in-depth overview of the properties and biomedical applications of pHEMA for bone tissue regeneration, wound healing, cancer therapy (stimuli and non-stimuli responsive systems), and ophthalmic applications (contact lenses and ocular drug delivery). As this polymer has been widely applied in ophthalmic applications, a specific consideration has been devoted to this field. Pure pHEMA does not possess antimicrobial properties and the site where the biomedical device is employed may be susceptible to microbial infections. Therefore, antimicrobial strategies such as the use of silver nanoparticles, antibiotics, and antimicrobial agents can be utilized to protect against infections. Therefore, the antimicrobial strategies besides...
Electrospun porous bone scaffolds are known to imitate the extracellular matrix very well and pro... more Electrospun porous bone scaffolds are known to imitate the extracellular matrix very well and provide an environment through which the tissue formation is enhanced. Although polymeric scaffolds have a great potential in bone tissue regeneration, their weak bioactivity (bone bonding ability) and mechanical properties have left room for improvement. Therefore, the present study focused on the developing a ternary multifunctional platform composed of polycaprolactone (PCL)/silk fibroin (SF)/Zn-substituted Mg2SiO4 nanoparticles for bone tissue regeneration. This study is composed of two connected sections including synthesis and characterization of Mg(2-x)ZnxSiO4, x = 0, 0.5, 1, 1.5, 2 through surfactant-assisted sol-gel technique followed by incorporation of the nanoparticles into PCL/SF hybrid scaffold via electrospinning technique. The weight ratios of polymers and ceramic nanoparticles were optimized to reach desirable textural-porosity, pore size, and fiber diameter-and mechanical properties. Having optimized the ternary scaffold, it was then undergone different physical, chemical, and biological tests in vitro. A precise comparison study between the ternary (PCL/SF/ceramic nanoparticles), binary (PCL/SF), and pure PCL was made to shed light on the effect of each composition on the applicability of ternary scaffold. The overall results confirmed that the Mg1Zn1SiO4 nanoparticles-incorporated PCL/SF scaffold with fluorescence property was the one yielding the highest Young's modulus and desirable textural properties. The ternary scaffold showed improved biological properties making it a promising candidate for further studies towards bone tissue regeneration.
As a bone scaffold, meeting all basic requirements besides dealing with other bone-related issues... more As a bone scaffold, meeting all basic requirements besides dealing with other bone-related issues—bone cancer and accelerated regeneration—is not expected from traditional scaffolds, but a newer class of scaffolds called multifunctional. From a clinical point of view, being a multifunctional scaffold means reducing in healing time, direct costs—medicine, surgery, and hospitalization—and indirect costs—loss of mobility, losing job, and pain. The main aim of the present review is following the multifunctional bone scaffolds trend to deal with both bone regeneration and cancer therapy. Special consideration is given to different fabrication techniques which have been applied to yield these materials spanning from traditional to modern ones. Moreover, the hierarchical structure of bone plus bone cancers and available medicines to them are introduced to familiarize the potential reader of review with the pluri-disciplinary essence of the field. Eventually, a brief discussion relating to the future trend of these materials is provided.
Abstract This is a comprehensive study reporting the fabrication of highly porous Gehlenite scaff... more Abstract This is a comprehensive study reporting the fabrication of highly porous Gehlenite scaffold (Ca2Al2SiO7)—both with and without surface modification—for the first time. The sintering temperature of Gehlenite scaffolds was optimized. Next, the optimized Gehlenite scaffold was coated by polycaprolactone (PCL)-Forsterite (Mg2SiO4) nanocomposite to improve the scaffold’s brittleness and biological properties. 1375 °C was found to be the optimized sintering temperature by which the Gehlenite scaffold was consolidated. Different PCL and Forsterite concentrations were separately applied on the optimized scaffold to yield a complete nanocomposite coating without clogging the macroporous structure. The bioactivity, degradation rate, cell viability, attachment and proliferation of three different scaffolds—non-coated (sintered at 1375 °C), PCL-coated and PCL/Forsterite nanocomposite-coated—were scrutinized and compared to each other in vitro. Based on our results, it is concluded that the PCL-Forsterite nanocomposite-coated scaffold with desired physical, chemical and biological-related properties has a great potential for bone tissue regeneration.
3D multifunctional bone scaffolds have recently attracted more attention in bone tissue engineeri... more 3D multifunctional bone scaffolds have recently attracted more attention in bone tissue engineering because of addressing critical issues like bone cancer and inflammation beside bone regeneration. In this study, a 3D bone scaffold is fabricated from Mg2SiO4-CoFe2O4 nanocomposite which is synthesized via a two-step synthesis strategy and then the scaffold's surface is modified with poly-3-hydroxybutyrate (P3HB)-ordered mesoporous magnesium silicate (OMMS) composite to improve its physicochemical and biological properties. The Mg2SiO4-CoFe2O4 scaffold is fabricated through polymer sponge technique and the scaffold exhibits an interconnected porous structure in the range of 100-600 μm. The scaffold is then coated with OMMS/P3HB composite via dip coating and the physical, chemical, and biological-related properties of OMMS/P3HB composite-coated scaffold are assessed and compared to the non-coated and P3HB-coated scaffolds in vitro. It is found that, on the one hand, P3HB increases the cell attachment, proliferation, and compressive strength of the scaffold, but on the other hand, it weakens the bioactivity kinetic. Addition of OMMS to the coating composition is accompanied with significant increase in bioactivity kinetic. Besides, OMMS/P3HB composite-coated scaffold exhibits higher drug loading capacity and more controlled release manner up to 240 h than the other samples because of OMMS which has a high surface area and ordered mesoporous structure suitable for controlled release applications. The overall results indicate that OMMS/P3HB coating on Mg2SiO4-CoFe2O4 scaffold leads to a great improvement in bioactivity, drug delivery potential, compressive strength, cell viability, and proliferation. Moreover, OMMS/P3HB composite-coated scaffold has heat generation capability for hyperthermia-based bone cancer therapy and so it is suggested as a multifunctional scaffold with great potentials for bone cancer therapy and regeneration.
Polymers, due to their high molecular weight, tunable architecture, functionality, and buffering ... more Polymers, due to their high molecular weight, tunable architecture, functionality, and buffering effect for endosomal escape, possess unique properties as a carrier or prophylactic agent in preventing pandemic outbreak of new viruses. Polymers are used as a carrier to reduce the minimum required dose, bioavailability, and therapeutic effectiveness of antiviral agents. Polymers are also used as multifunctional nanomaterials to, directly or indirectly, inhibit viral infections. Multifunctional polymers can interact directly with envelope glycoproteins on the viral surface to block fusion and entry of the virus in the host cell. Polymers can indirectly mobilize the immune system by activating macrophages and natural killer cells against the invading virus. This review covers natural and synthetic polymers that possess antiviral activity, their mechanism of action, and the effect of material properties like chemical composition, molecular weight, functional groups, and charge density on...
Background: For a new biomaterial which is going to be applied in bone tissue regeneration, bioac... more Background: For a new biomaterial which is going to be applied in bone tissue regeneration, bioactivity (bone bonding ability) and desirable mechanical properties are very essential parameters to take into consideration. In the present study, the gehlenite's mechanical properties and bioactivity are assessed and compared with hydroxyapatite (HA) for bone tissue regeneration. Method: Gehlenite and HA nanoparticles are synthesized through sol–gel method and coprecipitation technique, respectively, and their physical and chemical properties are characterized through X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy. Results: The results prove that the gehlenite and HA phases without any undesirable phase are obtained, and the particles of both compounds are in the nanometer range with spherical morphology. The compressive strength of both compounds are assessed, and the values for gehlenite and HA disks are 144 ± 5 and 150 ± 4.8 MPa, r...
Abstract In this study, a new nanocomposite scaffold entailing poly glycerol sebacate/polycaprola... more Abstract In this study, a new nanocomposite scaffold entailing poly glycerol sebacate/polycaprolactone/carbon quantum dots (PGS/PCL/CQDs) was designed and fabricated for cardiac muscle regeneration. The PGS/PCL fibrous scaffolds were electrospun in disparate weight ratios—2:1 and 1:1. Next, different amounts of CQDs (0.5 and 1 wt %) were incorporated in the PGS/PCL fibers to reach a ternary nanocomposite scaffold. Besides characterizing the physical and chemical properties of scaffolds—morphology, chemical bonds, mechanical properties, wettability, and electrical conductivity—the biological properties including cytotoxicity, cell attachment and proliferation, and degradation rate were assessed in vitro. To give proof of CQDs inclusion in the fibers, transmission electron microscopy and fluorescent assay were applied. Addition of both PGS and CQDs to the PCL fibers resulted in a significant decrease in the mean fiber diameter of ternary nanocomposite scaffold from 862 ± 167 down to 376.82 ± 150 nm. The electrical conductivity of scaffolds was increased through the incorporation of CQDs, whereas the addition of CQDs up to 1 wt % led to a decrease in the cell viability. According to the weight ratio optimization, the PGS/PCL/CQDs scaffold (2:1:0.5) outperformed the others in physical, chemical, and biological properties; the scaffold's Young's modulus, elongation at break, and ultimate tensile strength were 11 ± 1 MPa, 10 ± 1 mm, and 5 ± 1 MPa, respectively. Moreover, the cell viability of optimized nanocomposite scaffold was found to be very close to the negative control proving its desirable cell compatibility. Therefore, the optimized PGS/PCL/CQDs nanocomposite scaffold can be potentially promising for cardiac muscle tissue engineering.
Poly(2-hydroxyethyl methacrylate) (pHEMA) as a biomaterial with excellent biocompatibility and cy... more Poly(2-hydroxyethyl methacrylate) (pHEMA) as a biomaterial with excellent biocompatibility and cytocompatibility elicits a minimal immunological response from host tissue making it desirable for different biomedical applications. This article seeks to provide an in-depth overview of the properties and biomedical applications of pHEMA for bone tissue regeneration, wound healing, cancer therapy (stimuli and non-stimuli responsive systems), and ophthalmic applications (contact lenses and ocular drug delivery). As this polymer has been widely applied in ophthalmic applications, a specific consideration has been devoted to this field. Pure pHEMA does not possess antimicrobial properties and the site where the biomedical device is employed may be susceptible to microbial infections. Therefore, antimicrobial strategies such as the use of silver nanoparticles, antibiotics, and antimicrobial agents can be utilized to protect against infections. Therefore, the antimicrobial strategies besides...
Electrospun porous bone scaffolds are known to imitate the extracellular matrix very well and pro... more Electrospun porous bone scaffolds are known to imitate the extracellular matrix very well and provide an environment through which the tissue formation is enhanced. Although polymeric scaffolds have a great potential in bone tissue regeneration, their weak bioactivity (bone bonding ability) and mechanical properties have left room for improvement. Therefore, the present study focused on the developing a ternary multifunctional platform composed of polycaprolactone (PCL)/silk fibroin (SF)/Zn-substituted Mg2SiO4 nanoparticles for bone tissue regeneration. This study is composed of two connected sections including synthesis and characterization of Mg(2-x)ZnxSiO4, x = 0, 0.5, 1, 1.5, 2 through surfactant-assisted sol-gel technique followed by incorporation of the nanoparticles into PCL/SF hybrid scaffold via electrospinning technique. The weight ratios of polymers and ceramic nanoparticles were optimized to reach desirable textural-porosity, pore size, and fiber diameter-and mechanical properties. Having optimized the ternary scaffold, it was then undergone different physical, chemical, and biological tests in vitro. A precise comparison study between the ternary (PCL/SF/ceramic nanoparticles), binary (PCL/SF), and pure PCL was made to shed light on the effect of each composition on the applicability of ternary scaffold. The overall results confirmed that the Mg1Zn1SiO4 nanoparticles-incorporated PCL/SF scaffold with fluorescence property was the one yielding the highest Young's modulus and desirable textural properties. The ternary scaffold showed improved biological properties making it a promising candidate for further studies towards bone tissue regeneration.
As a bone scaffold, meeting all basic requirements besides dealing with other bone-related issues... more As a bone scaffold, meeting all basic requirements besides dealing with other bone-related issues—bone cancer and accelerated regeneration—is not expected from traditional scaffolds, but a newer class of scaffolds called multifunctional. From a clinical point of view, being a multifunctional scaffold means reducing in healing time, direct costs—medicine, surgery, and hospitalization—and indirect costs—loss of mobility, losing job, and pain. The main aim of the present review is following the multifunctional bone scaffolds trend to deal with both bone regeneration and cancer therapy. Special consideration is given to different fabrication techniques which have been applied to yield these materials spanning from traditional to modern ones. Moreover, the hierarchical structure of bone plus bone cancers and available medicines to them are introduced to familiarize the potential reader of review with the pluri-disciplinary essence of the field. Eventually, a brief discussion relating to the future trend of these materials is provided.
Abstract This is a comprehensive study reporting the fabrication of highly porous Gehlenite scaff... more Abstract This is a comprehensive study reporting the fabrication of highly porous Gehlenite scaffold (Ca2Al2SiO7)—both with and without surface modification—for the first time. The sintering temperature of Gehlenite scaffolds was optimized. Next, the optimized Gehlenite scaffold was coated by polycaprolactone (PCL)-Forsterite (Mg2SiO4) nanocomposite to improve the scaffold’s brittleness and biological properties. 1375 °C was found to be the optimized sintering temperature by which the Gehlenite scaffold was consolidated. Different PCL and Forsterite concentrations were separately applied on the optimized scaffold to yield a complete nanocomposite coating without clogging the macroporous structure. The bioactivity, degradation rate, cell viability, attachment and proliferation of three different scaffolds—non-coated (sintered at 1375 °C), PCL-coated and PCL/Forsterite nanocomposite-coated—were scrutinized and compared to each other in vitro. Based on our results, it is concluded that the PCL-Forsterite nanocomposite-coated scaffold with desired physical, chemical and biological-related properties has a great potential for bone tissue regeneration.
3D multifunctional bone scaffolds have recently attracted more attention in bone tissue engineeri... more 3D multifunctional bone scaffolds have recently attracted more attention in bone tissue engineering because of addressing critical issues like bone cancer and inflammation beside bone regeneration. In this study, a 3D bone scaffold is fabricated from Mg2SiO4-CoFe2O4 nanocomposite which is synthesized via a two-step synthesis strategy and then the scaffold's surface is modified with poly-3-hydroxybutyrate (P3HB)-ordered mesoporous magnesium silicate (OMMS) composite to improve its physicochemical and biological properties. The Mg2SiO4-CoFe2O4 scaffold is fabricated through polymer sponge technique and the scaffold exhibits an interconnected porous structure in the range of 100-600 μm. The scaffold is then coated with OMMS/P3HB composite via dip coating and the physical, chemical, and biological-related properties of OMMS/P3HB composite-coated scaffold are assessed and compared to the non-coated and P3HB-coated scaffolds in vitro. It is found that, on the one hand, P3HB increases the cell attachment, proliferation, and compressive strength of the scaffold, but on the other hand, it weakens the bioactivity kinetic. Addition of OMMS to the coating composition is accompanied with significant increase in bioactivity kinetic. Besides, OMMS/P3HB composite-coated scaffold exhibits higher drug loading capacity and more controlled release manner up to 240 h than the other samples because of OMMS which has a high surface area and ordered mesoporous structure suitable for controlled release applications. The overall results indicate that OMMS/P3HB coating on Mg2SiO4-CoFe2O4 scaffold leads to a great improvement in bioactivity, drug delivery potential, compressive strength, cell viability, and proliferation. Moreover, OMMS/P3HB composite-coated scaffold has heat generation capability for hyperthermia-based bone cancer therapy and so it is suggested as a multifunctional scaffold with great potentials for bone cancer therapy and regeneration.
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Papers by Ashkan Bigham