Journal of Biomaterials Science Polymer Edition (J BIOMAT SCI-POLYM E )

Publisher: Brill Academic Publishers

Description

The Journal of Biomaterials Science, Polymer Edition publishes fundamental research on the properties of polymeric biomaterials and the mechanisms of interaction between such biomaterials and living organisms, with special emphasis on the molecular and cellular levels. The scope of the journal includes polymers for drug delivery, tissue engineering, large molecules in living organisms like DNA, proteins, and more. As such, the Journal of Biomaterials Science, Polymer Edition combines biomaterials applications in biomedical, pharmaceutical and biological fields.

  • Impact factor
    1.70
    Show impact factor history
     
    Impact factor
  • 5-year impact
    2.02
  • Cited half-life
    7.50
  • Immediacy index
    0.43
  • Eigenfactor
    0.01
  • Article influence
    0.49
  • Website
    Journal of Biomaterials Science, Polymer Edition website
  • Other titles
    Journal of biomaterials science. Polymer ed., Polymer edition
  • ISSN
    0920-5063
  • OCLC
    21171173
  • Material type
    Periodical, Internet resource
  • Document type
    Journal / Magazine / Newspaper, Internet Resource

Publisher details

Brill Academic Publishers

  • Pre-print
    • Author can archive a pre-print version
  • Post-print
    • Author can archive a post-print version
  • Conditions
    • Pre-print can only be deposited after acceptance for peer-review
    • Author's Post-print on author's personal website, institutional website or institutional repository
    • Publisher version may be posted on author's personal website only
    • Publisher's version/PDF cannot be used in institutional repository
    • Must link to publisher version
    • Published source must be acknowledged
  • Classification
    ​ green

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: Gelatin is one of the most promising materials in tissue engineering as a scaffold component. This biopolymer indicates biocompatibility and bioactivity caused by the existence of specific amino acid sequences, being preferred sites for interactions with cells, with high similarity to natural extracellular matrix. The present paper does not aspire to be a full review of electrospinning of gelatin and gelatin containing nanofibers as scaffolds in tissue engineering. It is focused on the still open question of the role of the higher order structures of gelatin in scaffold's bioactivity/functionality. Gelatin molecules can adopt various conformations depending on temperature, solvent, pH, etc. Our review indicates the potential ways for formation of α-helix conformation during electrospinning and the methods of further structure stabilization. It is intuitively expected that the native α-helix conformation appearing as a result of partial renaturation of gelatin can be beneficial from the viewpoint of bioactivity of scaffolds, providing thus a much cheaper alternative approach as opposed to expensive electrospinning of native collagen.
    Journal of Biomaterials Science Polymer Edition 10/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: A novel method of constructing a glycosylated surface on poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] membrane surface for the selective adsorption of low-density lipoprotein (LDL) was developed, which involved the photoinduced graft polymerization of acrylic acid followed by the chemical binding of carboxyl groups with glucosamine in the presence of 1-ethyl-3-(dimethyl-aminopropyl) carbodiimide hydrochloride and N-hydroxy-succinimide. The chemical structures of the fabricated membranes were characterized by attenuated total reflectance Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Zeta potential and water contact angle measurements were performed to investigate the surface charge and wettability of the membranes, respectively. An enzyme linked immunosorbent assay was used to measure the LDL adsorption on the plain and modified membrane surfaces. It was found that the surface glycosylation of P(3HB-co-4HB) membrane greatly enhanced the affinity interactions with LDL and the absorbed LDL could be easily desorbed with eluents, indicating a specific and reversible binding of LDL to the surface. Furthermore, the hemocompatibility of glycosylated membrane was improved as examined by platelet adhesion. The results suggest that the glycosylated P(3HB-co-4HB) membrane is promising for application in LDL apheresis therapy.
    Journal of Biomaterials Science Polymer Edition 10/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: To investigate the effects of preparation methods on the bone formation potential of apatite-coated chitosan microspheres, coacervate precipitation method and emulsion cross-linking method were chosen to prepare chitosan microspheres, and then apatite coatings were deposited using simulated body fluid. Rat bone marrow-derived mesenchymal stem cells (BMSCs) were seeded on these microspheres. Cell adhesion, proliferation, and differentiation potential were monitored. For in vivo analysis, some cell/microsphere constructs were implanted in the subcutaneous pockets of male Wistar rats. After 3, 6, 12 weeks, the samples were retrieved and stained with hematoxylin and eosin (HE). Some cell/microsphere constructs were implanted in the calvarial defects of rats. Micro-CT and HE analysis were performed to analyze the new bone formation. It was found that BMSCs on apatite-coated emulsion cross-linked microspheres (EM1) exhibited better proliferation and differentiation than cells on apatite-coated coacervate-precipitated microspheres. The in vivo results showed that no bone was observed in ectopic areas. While in calvarial defects, both histological slices and Micro-CT images demonstrated that a substantial amount of new bone was formed in the EM1/BMSCs construct. These data suggest that preparation methods do exert great influence on the in vitro cell behaviors and in vivo orthotopic bone regeneration of apatite-coated chitosan microspheres. Appropriate method should be considered when preparing chitosan microspheres for bone tissue engineering scaffold.
    Journal of Biomaterials Science Polymer Edition 10/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Porphyrins typically show preferential uptake and retention by tumor tissues via receptor-mediated endocytosis of low-density lipoproteins. To investigate the relative importance of active and passive targeting strategies, the synthesis, characterization, in vitro uptake, and in vivo biodistribution of specific targeting porphyrin HPMA [HPMA: N-(2-hydroxypropyl)methacrylamide] copolymer tracer poly(HPMA)-porphyrin-DTPA-(99m)Tc (DTPA: diethylenetriaminepentaacetic acid), nonspecific targeting HPMA copolymer tracer poly(HPMA)-DTPA-(99m)Tc, and nontargeting tracer DTPA-(99m)Tc are described in this study. The results showed that the cellular accumulation of poly(HPMA)-porphyrin-DTPA-(99m)Tc complex was found to be time-dependent. The uptake of poly(HPMA)-porphyrin-DTPA-(99m)Tc was significantly higher than that of poly(HPMA)-DTPA-(99m)Tc, indicating that uptake of the poly(HPMA)-porphyrin-DTPA-(99m)Tc was active binding. The uptake of poly(HPMA)-DTPA-(99m)Tc was significantly higher than that of DTPA-(99m)Tc, suggesting that uptake of the poly(HPMA)-DTPA-(99m)Tc was passive binding. Twenty-four hour necropsy data in the hepatocellular carcinoma tumor model showed significantly higher (p < 0.001) tumor localization for poly(HPMA)-porphyrin-DTPA-(99m)Tc (5.18 ± 0.50% ID/g [percentage injected dose per gram tissue]) compared with poly(HPMA)-DTPA-(99m)Tc (2.69 ± 0.15% ID/g) and DTPA-(99m)Tc (0.83 ± 0.03% ID/g). Moreover, higher T/B for poly(HPMA)-porphyrin-DTPA-(99m)Tc indicated reduced extravasation of the targeted polymeric conjugates in normal tissues. Thus, the poly(HPMA)-porphyrin-DTPA-(99m)Tc is a potential macromolecular tumor targeting molecular agent.
    Journal of Biomaterials Science Polymer Edition 10/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: This article describes a chitosan-collagen composite membrane as corneal tissue-engineering biomaterials. The membrane was prepared by dissolving the chitosan into collagen with the weight ratio of 0, 15, 30, 45, 60, and 100%, followed by crosslinked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. Mechanical properties, contact angles, and optical transmittance were determined and compared between chitosan membrane and crosslinking composite membrane. As a result, the optical transparency and mechanical strength of the chitosan-collagen membranes were significantly better than that of the sample of chitosan. In addition, in vitro cell culture studies revealed that the collagen has no negative effect on the cell morphology, viability, and proliferation and possess good biocompatibility. Overall, the dendrimer crosslinked chitosan-collagen composite membranes showed promising properties that suggest that these might be suitable biomaterials for corneal tissue-engineering applications.
    Journal of Biomaterials Science Polymer Edition 10/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Polycaprolactone (PCL)/hydroxyapatite (HA) composite scaffolds were prepared by combining solvent casting and salt particulate leaching with a polymer leaching technique. The hydrophilicity of the dual-leached scaffold was improved by alkaline (NaOH) treatment. Well-defined interconnected pores were detected by scanning electron microscopy. The water absorption capacity of the NaOH-treated PCL/HA dual-leached scaffold increased greatly, confirming that the hydrophilicity of the scaffold was improved by NaOH treatment. The compressive modulus of the PCL/HA dual-leached scaffold was greatly increased by the addition of HA particles. An indirect evaluation of the cytotoxicity of all PCL dual-leached scaffolds with mouse fibroblastic cells (L929) and mouse calvaria-derived pre-osteoblastic cells (MC3T3-E1) indicated that the PCL dual-leached scaffolds are non-toxic to cells. The ability of the scaffolds to support mouse calvaria-derived pre-osteoblastic cell (MC3T3-E1) attachment, proliferation, differentiation, and mineralization was also evaluated. Although the viability of cells was lower on the PCL/HA dual-leached scaffold than on the tissue-culture polystyrene plates (TCPS) and on the other substrates at early time points, both the PCL and NaOH-treated PCL/HA dual-leached scaffolds supported the attachment of MC3T3-E1 at significantly higher levels than TCPS. During the proliferation period (days 1-3), all of the PCL dual-leached scaffolds were able to support the proliferation of MC3T3-E1 at higher levels than the TCPS; in addition, the cells grown on NaOH-treated PCL/HA dual-leached scaffolds proliferated more rapidly. The cells cultured on the surfaces of NaOH-treated PCL/HA dual-leached scaffolds had the highest rate of mineral deposition.
    Journal of Biomaterials Science Polymer Edition 10/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Lysine-derived polyurethane scaffolds (LTI-PUR) support cutaneous wound healing in loose-skinned small animal models. Due to the physiological and anatomical similarities of human and pig skin, we investigated the capacity of LTI-PUR scaffolds to support wound healing in a porcine excisional wound model. Modifications to scaffold design included the addition of carboxymethylcellulose (CMC) as a porogen to increase interconnectivity and an additional plasma treatment (Plasma) to decrease surface hydrophobicity. All LTI-PUR scaffold and formulations supported cellular infiltration and were biodegradable. At 15 days, CMC and plasma scaffolds simulated increased macrophages more so than LTI PUR or no treatment. This response was consistent with macrophage-mediated oxidative degradation of the lysine component of the scaffolds. Cell proliferation was similar in control and scaffold-treated wounds at 8 and 15 days. Neither apoptosis nor blood vessel area density showed significant differences in the presence of any of the scaffold variations compared with untreated wounds, providing further evidence that these synthetic biomaterials had no adverse effects on those pivotal wound healing processes. During the critical phase of granulation tissue formation in full thickness porcine excisional wounds, LTI-PUR scaffolds supported tissue infiltration, while undergoing biodegradation. Modifications to scaffold fabrication modify the reparative process. This study emphasizes the biocompatibility and favorable cellular responses of PUR scaffolding formulations in a clinically relevant animal model.
    Journal of Biomaterials Science Polymer Edition 10/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Bacterial cellulose (BC) is an interesting biopolymer produced by bacteria having superior properties. BC produced by Gluconoacetobacter hansenii (strain NCIM 2529) under shaking condition and explored for its applications in dye removal and bioadsorption of protein and heavy metals. Purity of BC was confirmed by Fourier transform infrared spectroscopy and scanning electron microscopy (SEM) analysis. BC removed azo dye and Aniline blue (400 mg/L) with 80% efficiency within 60 min. The adsorption and elution of Bovine serum albumin (BSA) and heavy metals like lead, cadmium and nickel (Pb(2+), Cd(2+) and Ni(2+)) was achieved with BC which confirms the exclusion ability with reusability. The BSA adsorption quantity was increased with increase in protein concentration with more than 90% adsorption and elution ratio. The effect of pH and temperature on BSA adsorption has been investigated. Bioadsorption (82%) and elution ratio (92%) of BC for Pb(2+) was more when compared with Cd(2+) (41 and 67%) and Ni(2+) (33 and 85%), respectively. BC was also explored as soil conditioner to increase the water-holding capacity and porosity of soil. The results elucidated the significance of BC as renewable effective ecofriendly bioadsorption agent.
    Journal of Biomaterials Science Polymer Edition 10/2014; Accepted.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Recent studies revealing stem cell behavior dependence on mechanical properties of a substrate has initiated the need to probe matrix mechanics and its influence on stem cell fate in a physiologically relevant three-dimensional (3D) microenvironment. We investigated the proliferative and osteogenic potentials of Wharton's jelly mesenchymal stem cells (WJMSCs) immobilized in alginate microspheres with respect to the mechanical properties of alginate hydrogels (1, 1.5 and 2% (w/v)) post incubation in a simulated in vivo environment. Compressive moduli, degradation profile, and swelling kinetics of the hydrogels varied proportionally with alginate concentration and with exposure to simulated conditions. Degradation profile and morphological analysis showed that hydrogels exhibiting high modulus (2% w/v) remained the most intact at the end of day 21. High cell viability in all conditions was observed throughout the culture period. Low-modulus hydrogels (1% w/v) facilitated proliferation of WJMSCs whereas high-modulus hydrogels demonstrated better osteogenic differentiation inferred by an up regulation of osteo-specific genes, expressions of osteocalcin, and quantification of calcium deposition. These findings present a step forward in the development of application-specific hydrogel matrices for stem cell-based tissue engineering.
    Journal of Biomaterials Science Polymer Edition 09/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, copolymers composed of antibacterial monomer containing ciprofloxacin, methyl methacrylate (MMA), and 2-perfluorooctylethyl methacrylate (FMA) were prepared, and the surface properties and antibacterial performance of the copolymers and blends-mixed PMMA were investigated. Surface characterization using dynamic contact angle measurement and X-ray photoelectron spectroscopy showed that anti-adhesive fluorinated moieties and antimicrobial moieties were highly concomitant on the material surface. All the copolymers and blends films exhibited excellent antibacterial properties. It was found that the fluorinated antibacterial copolymers showed significantly enhanced antibacterial efficiency toward Escherichia coli bacterium, and even markedly prevented the formation of biofilm for long term. The PMMA films blended with fluorinated antibacterial polymer also show similar results. In contrast, the common copolymer without fluorinated units cannot effectively resist bacterial adhesion, proliferation, and prevent biofilm formation. The desirable antibacterial polymer prohibiting the biofilm formation performance of copolymer with special push-me/pull-you structure which weaken the interaction among polymer chains resulted in the more easy segregation of ciprofloxacin on surface in real environment by the help of synergistic effect of fluorinated units, potentially enabling the design of new self-decontaminating biomaterials for control biofouling.
    Journal of Biomaterials Science Polymer Edition 09/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose: The antifungal agent natamycin can effectively form inclusion complexes with beta-cyclodextrin (β-CD) and 2-hydroxypropyl-β-cyclodextrin (HP-βCD) to improve the water solubility of natamycin by 16-fold and 152-fold, respectively (Koontz, J. Agric. Food. Chem. 2003). The purpose of this study was to develop contact lens materials functionalized with methacrylated β-CD (MβCD) and methacrylated HP-βCD (MHP-βCD), and to evaluate their ability to deliver natamycin in vitro. Methods: Model conventional hydrogel (CH) materials were synthesized by adding varying amounts of MβCD and MHP-βCD (0, 0.22, 0.44, 0.65, 0.87, 1.08% of total monomer weight) to a monomer solution containing 2-hydroxyethyl methacrylate (HEMA). Model silicone hydrogel (SH) materials were synthesized by adding similar concentrations of MβCD and MHP-βCD to N,N-dimethylacrylamide (DMAA)/10% 3-methacryloxypropyltris(trimethylsiloxy)silane (TRIS). The gels were cured with UV light, washed with ethanol and then, hydrated for 24 h (h). The model materials were then incubated with 2 mL of 100 μg/mL of natamycin in phosphate buffered saline (PBS) pH 7.4 for 48 h at room temperature. The release of natamycin from these materials in 2 mL of PBS, pH 7.4 at 32 ± 2 °C was monitored using UV-vis spectrophotometry at 304 nm over 24 h. Results: For both CH and SH materials, functionalization with MβCD and MHP-βCD improved the total amount of drugs released up to a threshold loading concentration, after which further addition of methacrylated CDs decreased the amount of drugs released (p < 0.05). The addition of CDs did not extend the drug release duration; the release of natamycin by all model materials reached a plateau after 12 h (p < 0.05). Overall, DMAA/10% TRIS materials released significantly more drug than HEMA materials (p < 0.05). The addition of MHP-βCD had a higher improvement in drug release than MβCD for both HEMA and DMAA/10% TRIS gels (p < 0.05). Conclusions: A high loading concentration of methacrylated CDs decreases overall drug delivery efficiency, which likely results from an unfavorable arrangement of the CDs within the polymer network leading to reduced binding of natamycin to the CDs. HEMA and DMAA/10% TRIS materials functionalized with MHP-βCD are more effective than those functionalized with MβCD to deliver natamycin.
    Journal of Biomaterials Science Polymer Edition 09/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Biofouling is a universal problem in various applications ranging from water purification to implantable biomedical devices. Recent advances in surface modification have created a rich library of antifouling surface chemistries, many of which can be categorized into one of the two groups: hydrophilic surfaces or amphiphilic surfaces. We report the straightforward preparation of antifouling thin film coatings in both categories via initiated chemical vapor deposition. A molecular force spectroscopy-based method is demonstrated as a rapid and quantitative assessment tool for comparing the differences in antifouling characteristics. The fouling propensity of single molecules, as opposed to bulk protein solution or bacterial culture, is assessed. This method allows for the interrogation of molecular interaction without the complication resulted from protein conformational change or micro-organism group interactions. The molecular interaction follows the same trend as bacterial adhesion results obtained previously, demonstrating that molecular force probe is a valid method for the quantification and mechanistic examination of fouling. In addition, the molecular force spectroscopy-based method is able to distinguish differences in antifouling capability that is not resolvable by traditional static protein adsorption tests. To lend further insight into the intrinsic fouling resistance of zwitterionic and amphiphilic surface chemistries, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, advancing and receding water contact angles, and atomic force microscopy are used to elucidate the film properties that are relevant to their antifouling capabilities.
    Journal of Biomaterials Science Polymer Edition 09/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Poly(lactic acid) (PLA) nanoparticles (NPs) are the most promising polymer NPs for drug delivery and targeting. However, they are easily recognized as a foreign body and rapidly cleared from the body by the mononuclear phagocyte system. Cell membrane mimetic random copolymers, bearing both zwitterionic phosphorylcholine groups and hydrophobic butyl side chains (PMB) and additional cross-linkable trimethoxysilylpropyl side chains (PMBT), were synthesized and coated on PLA NPs. Effects of the zwitterionic copolymer coatings on the NP size distribution, dispersion stability, and drug release behavior were investigated. Furthermore, the effect of the coatings on phagocytosis was also investigated. Compared with conventional polyvinyl alcohol coating, the cell membrane mimetic copolymer coatings decreased the size and increased the stability of the PLA NPs aqueous dispersions. More importantly, doxorubicin (DOX) release was well controlled and NPs phagocytosis by mouse peritoneal macrophage was decreased to one-third when the nanoparticles were coated with PMBT. This simple and effective zwitterionic polymer coating strategy may serve as a new route to design and optimize long-circulating intravenously injectable nanoparticle drug carriers.
    Journal of Biomaterials Science Polymer Edition 09/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: The swollen brush structures of polycation and zwitterionic polymer brushes, such as poly(2-methacryloyloxyethyltrimethylammonium chloride) (PMTAC), poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), and poly[3-(N-2-methacryloyloxyethyl-N,N-dimethyl)ammonatopropanesulfonate] (PMAPS), in aqueous solutions of various ionic strengths were characterized by neutron reflectivity (NR) measurements. A series of the polyelectrolyte brushes were prepared by surface-initiated controlled radical polymerization on silicon substrates. A high-graft-density PMTAC brush in salt-free water (D2O) adopted a two-region step-like structure consisting of a shrunk region near the Si substrate surface and a diffuse brush region with a relatively stretched chain structure at the solution interface. The diffuse region of PMTAC was reduced with increase in salt (NaCl) concentration. The PMAPS brush in D2O formed a collapsed structure due to the strong molecular interaction between betaine groups, while significant increase in the swollen thickness was observed in salt aqueous solution. In contrast, no change was observed in the depth profile of the swollen PMPC brush in D2O with various salt concentrations. The unique solution behaviors of zwitterionic polymer brushes were described.
    Journal of Biomaterials Science Polymer Edition 09/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: This study examines the potential use of porous polycaprolactone (PCL) and polycaprolocatone/hydroxyapatite (PCL/HA) scaffolds fabricated through melt molding and porogen leaching for bone tissue engineering. While eliminating organic solvents is desirable, the process steps proposed in this study for uniformly dispersing HA particles (~5 μm in size) within the scaffold can also contribute to homogeneous properties for these porous composites. Poly(ethylene oxide) (PEO) was chosen as a porogen due to its similar density and melting point as PCL. Pore size of the scaffold was controlled by limiting the size of PCL and PEO particles used in fabrication. The percent of HA in the fabricated scaffolds was quantified by thermogravimetric analysis (TGA). Mechanical testing was used to compare the modulus of the scaffolds to that of bone, and the pore size distribution was examined with microcomputed tomography (μCT). Scanning electron microscopy (SEM) was used to examine the effect on scaffold morphology caused by the addition of HA particles. Both μCT and SEM results showed that HA could be incorporated into PCL scaffolds without negatively affecting scaffold morphology or pore formation. Energy-dispersive X-ray spectroscopy (EDS) and elemental mapping demonstrated a uniform distribution of HA within PCL/HA scaffolds. Murine calvaria-derived MC3T3-E1 cells were used to determine whether cells could attach on scaffolds and grow for up to 21 days. SEM images revealed an increase in cell attachment with the incorporation of HA into the scaffolds. Similarly, DNA content analysis showed a higher cell adhesion to PCL/HA scaffolds.
    Journal of Biomaterials Science Polymer Edition 09/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: The surface characteristics of biomaterials, especially regarding the sustained delivery of bone morphogenetic protein-2 (BMP-2), can possibly provide a novel and effective drug delivery system that can enhance osteogenesis. In this study, we evaluated the BMP-2 adsorption and release ability of the surface biomimetic hydroxyapatite (HAp) nanostructure on a new HAp-coated genipin-chitosan conjugation scaffold (HGCCS), and the resulting osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (BMSCs) in vitro. HGCCS exhibited a loading efficiency of 65% (1.30 μg), which is significantly higher than 28% (0.56 μg, p < 0.01) for the genipin cross-linked chitosan framework, as quantified by an enzyme-linked immunosorbent assay. More importantly, we found that the release of BMP-2 from HGGCS sustained for at least 14 days in simulated body fluid in vitro, which is much better than the burst release within 3 days for CGF. Moreover, the BMP-2 release from HGCCS induced an increase in alkaline phosphatase activity as an indicator of osteogenic differentiation of seeded BMSCs for 14 days in vitro. HGCCS also stimulated a high mRNA expression of osteogenic differentiation makers, runt-related transcription factor 2 for 14 days, osteopontin for 3 days, and osteocalcin for 14 days. The results of this study suggest that the surface biomimetic HAp nanostructure of HGCCS used as a delivery system for BMP-2 is capable of promoting osteogenic differentiation in vitro. These findings demonstrated that HAp nanostructure assembled on organic porous scaffold could work as both calcium source and absorption/release platform, which opened a new research avenue for cell growth factor release, and provided a promising strategy for design and preparation of bioactive scaffold for bone tissue engineering.
    Journal of Biomaterials Science Polymer Edition 08/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: The graft polymer Dex-g-PSSS was obtained through poly(sodium 4-styrene sulfonate) (PSSS) grafted on dextran(Dex) by using the cerium salt-hydroxyl group redox initiation system. The cross-linked microspheres C(Dex-g-PSSS) were synthesized by suspension polymerization with epichlorohydrin as the cross-linking agent. The chemical structure and physicochemical characteristics of C(Dex-g-PSSS) microspheres were represented by infrared spectroscopy (FTIR), optical microscope, and zeta potential analysis. The aim of the study is to constitute a colon-specific drug delivery system via molecular design, using C(Dex-g-PSSS) microspheres as the drug-carrying material and taking 5-fluorouracil (5-FU) as the model drug. The drug-carrying ability and mechanism of the cross-linked microspheres C(Dex-g-PSSS) for 5-FU were investigated. Finally, in vitro release tests for the drug-carrying microspheres were conducted. The experimental results show that in the medium with pH 2, the cross-linked microspheres C(Dex-g-PSSS) exhibit a strong adsorption ability for 5-FU because of strong electrostatic interactions and have an adsorption capacity of 154 ± 7.5 mg/g, displaying high drug-carrying efficiency. The in vitro release behavior of the drug-carrying microspheres is highly dependent on pH and dextranase. In the medium with pH 2, the drug-carrying microspheres do not release the drug and in the medium with pH 1, they release a little, whereas in the medium with pH 7.4, a sudden delivery phenomenon of the drug will occur, and in the presence of dextranase, a more sudden delivery phenomenon of the drug will occur, displaying an excellent colon-specific drug delivery behavior.
    Journal of Biomaterials Science Polymer Edition 08/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: A new type of cervical vertebra cage was prepared using a novel composite, calcium deficient hydroxyapatite/poly(amino acid) (HA/PAA), and its mechanical properties, in vitro stability and bioactivity, and in vivo biocompatibility were characterized. The results showed that the axial compressive loads of the HA/PAA cage were in the range of 10058-10612 N and the lateral compressive loads were in the range of 1180-2363 N, and varied with the height of the cervical vertebra cages. After immersion in simulated body fluid (SBF) for 16 weeks, the axial compressive loads of the cage decreased from 10058 to 7131 N and the lateral compressive loads decreased from 1180 to 479 N. In addition, the weight loss decreased 6.01%, showing that HA/PAA composites had good stability during the incubation period. The pH value of SBF was also monitored during the whole soaking period; it fluctuated in the range of 6.9-7.4. Scanning electron microscope and energy dispersive spectrometer results showed the cage was bioactive with a new apatite layer attached on the surface. The histological evaluation revealed that new bone tissue bonded tightly with the surfaces of the implants, showing excellent biocompatibility. In conclusion, the HA/PAA cage showed sufficient strength, good stability, bioactivity, and biocompatibility, and has potential applications for clinical cervical vertebrae repair.
    Journal of Biomaterials Science Polymer Edition 08/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Axially aligned nanofibrous matrices were evaluated as small diameter cardiovascular grafts. Grafts were prepared using the poly(L-lactic acid) (PLA) and poly(ε-caprolactone) (PCL) physical blends in the ratios of 75:25 and 25:75 with the dimension of (40 × 0.2 × 4) millimeter by electrospinning using dynamic collector (1500 RPM). Hydrophobicity and tensile stress were significantly higher in PLA-PCL (75:25), whereas tensile strain and fiber density were significantly higher in PLA-PCL (25:75). Properties such as anastomatic strength porosity, average pore size, degradation with retained fiber orientation, and thromboresistivity were comparable between blends. Human umbilical vascular endothelial cells (HUVEC) adhesion on the scaffolds was observed within 24 h. Cell viability and proliferation were rationally influenced by the aligned nanofibers. Gene expression reveals the grafts thromboresistivity, elasticity, and aided neovascularization. Thus, these scaffolds could be an ideal candidate for small diameter blood vessel engineering.
    Journal of Biomaterials Science Polymer Edition 08/2014;