Poly Glycerol Research Articles

Glycerol-based additives of poly(3-hydroxybutyrate) films

Glycerol (G), polyglycerols (PGs), glycerol triacetate (GTA), and glycerol tributyrate (GTB) were studied as additives of poly(3-hydroxybutyrate) (PHB). The effect of different concentrations (5–30%) of these compounds on microstructure and final properties of PHB films were evaluated. Microscopic studies revealed that samples with GTA and GTB presented uniform microstructure, meanwhile those containing G and PGs evidenced additives exudation. PHB exhibited a ring banded spherulitic structure and these additives, mainly G and PGs, induced modifications during polymer isothermal crystallization. All studied additives decreased PHB melting temperature, facilitating its thermal processability. GTA and GTB addition induced a reduction in PHB glass transition temperature, demonstrating their plasticizing effect. PHB films with GTA and GTB showed the best mechanical performance since they presented the highest deformation at break and the lowest maximum tensile strength, especially those with 30% GTB. Otherwise, G and PGs addition decreased films mechanical properties due to a prodegradative effect induced by them. GTB and PGs increased films water vapor permeability, meanwhile G and GTA decreased this barrier property.

An innovative approach to fabricate a thermosensitive melatonin‐loaded conductive pluronic/chitosan hydrogel for myocardial tissue engineering

AbstractThis study aimed at designing and fabrication of a novel injectable and thermosensitive melatonin‐loaded pluronic/chitosan hydrogel containing gold nanoparticles (GNPs) and poly glycerol sebacate (PGS) for myocardial tissue engineering. The PGS nanoparticles were used as the melatonin (drug model) carrier. The gelation time, syringeability, stability, and swelling of the hydrogel were scrutinized. Rheological properties, chemical composition, and morphology of the samples were also investigated. The effect of GNPs addition on the electrical conductivity of hydrogel was assessed. The cytotoxicity of hydrogels was assessed through MTT assay in the exposure of H9C2 cells up to 7 days. Scanning electron microscopy was applied to evaluate the morphology of seeded cells. The synthesis parameters of PGS nanoparticles were optimized through which 2.5%w/v of PGS and 1:10 organic phase to aqueous phase (O/A) ratio were found desirable. The optimum hydrogel illustrated 2 min gelation time and was stable up to 20 days with 5% swelling in the first 12 h into phosphate buffered saline. The GNPs with a uniform distribution rendered the hydrogel electrically conductive (1500 μS/cm). According to the MTT assay results, 3.125 μM melatonin was considered as the suitable concentration by which a significant increase in the cell viability was observed. The results exhibited that the prepared hydrogel composed of pluronic/chitosan/GNPs, and 3.125 μM melatonin‐loaded PGS nanoparticles could be applied as a promising scaffold for myocardial tissue engineering.

Complement activation induced by PEG enhances humoral immune responses against antigens encapsulated in PEG-modified liposomes

Splenic marginal zone B (MZ-B) cells have attracted attention as alternative antigen-presenting cells. We recently developed an original delivery system, using PEGylated liposomes (PEG-Lip) to deliver antigens to MZ-B cells. In this system, to induce antigen-specific immunity, empty PEG-Lip and antigen-containing PEG-Lip were intravenously (i.v.) injected sequentially at 3 day intervals. Since complement activation by the second dose is required for the delivery of antigen-containing PEG-Lip to splenic MZ-B cells, we investigated the ability of liposomes, modified with various PEG derivatives having different functional terminal groups (methoxy PEG (CH3O-PEG), hydroxy PEG (HO-PEG) or polyglycerol (PG), to activate the complement system and deliver a model antigen, ovalbumin (OVA), to splenic MZ-B cells in vitro and in vivo. Hydroxy PEG-modified liposomes (HO-PEG-Lip) both activated the complement system in vitro, and facilitated the preferential association of HO-PEG-lip with MZ–B cells in vitro. Manipulating HO-PEG density, in particular a density of 2 mol% in total lipids, significantly enhanced the association of HO-PEG-Lip with splenic MZ-B cells in vivo. Consequently, a single i.v. injection of HO-PEG-Lip (2 mol%) containing OVA induced OVA-specific IgG response. Our immunization system with HO-PEG-Lip, achieved efficient antigen delivery to MZ-B cells after a single i.v. injection, improving on our previous immunization system. This new delivery technique may be an improved, simple, antigen delivery system to MZ-B cells that induces meaningful levels of humoral immune response.

Alkaline-Based Catalysts for Glycerol Polymerization Reaction: A Review

Polyglycerols (PGs) are biocompatible and highly functional polyols with a wide range of applications, such as emulsifiers, stabilizers and antimicrobial agents, in many industries including cosmetics, food, plastic and biomedical. The demand increase for biobased PGs encourages researchers to develop new catalytic systems for glycerol polymerization. This review focuses on alkaline homogeneous and heterogeneous catalysts. The performances of the alkaline catalysts are compared in terms of conversion and selectivity, and their respective advantages and disadvantages are commented. While homogeneous catalysts exhibit a high catalytic activity, they cannot be recycled and reused, whereas solid catalysts can be partially recycled. The key issue for heterogenous catalytic systems, which is unsolved thus far, is linked to their instability due to partial dissolution in the reaction medium. Further, this paper also reviews the proposed mechanisms of glycerol polymerization over alkaline-based catalysts and discusses the various operating conditions with an impact on performance. More particularly, temperature and amount of catalyst are proven to have a significant influence on glycerol conversion and on its polymerization extent.

Cellular uptake of self-emulsifying drug-delivery systems: polyethylene glycol versus polyglycerol surface.

Aim: Comparison of the impact of polyethylene glycol (PEG) and polyglycerol (PG) surface decoration on self-emulsifying drug delivery system (SEDDS)-membrane interaction and cellular uptake. Materials &methods: PEG-, PEG/PG- and PG-SEDDS were assessed regarding their self-emulsifying properties, surface charge, bile salt fusibility, cellular uptake and interaction with endosome-mimicking membranes. Results: SEDDS exhibited droplet sizes between 150 and175nm, a narrow size distribution and self-emulsified within 7min. Higher PEG-surfactant amounts in SEDDS resulted in charge-shielding and thus in a decrease of ζ potential up to Δ11mV. The inert PEG-surface hampered bile salt fusion and interfered SEDDS-cell interaction. By reducing the PEG-surfactant amount to 10%, cellular uptake increased twofold compared with PEG-SEDDS containing 40% PEG-surfactant. PG-SEDDS containing no PEG-surfactants showed a threefold increased cellular uptake. Furthermore, complete replacement of PEG-surfactants by PG-surfactants led to enhanced cellular interaction and improved disruption endosome-like membranes. Conclusion:PG-surfactants demonstrated high potential to address PEG-surface associated drawbacks in SEDDS.

Folate-PG modified halloysite nanotube for enhancing tumor targeting and anticancer efficacy

Halloysite nanotubes have been gradually applied in the field of biomedicine, due to their attractive properties including biocompatibility, nontoxicity, hydrophilic and low-cost. Here, polyglycerol (PG) is used to wrap the surface of Hal to yield Hal-PG, so that there are a large number of hydroxyl groups on the surface of Hal-PG. Then, Hal-PG-FA nanocomplexes were prepared by combining folate (FA) with Hal-PG via esterification reaction. Thereafter, doxorubicin (DOX) was loaded on novel targeted anticancer delivery system Hal-PG-FA that can bind specifically to tumor cells that overexpressed the folate receptor. The obtained nanomaterials were fully characterized using FT-IR, TEM, XPS, TGA and DLS techniques. Moreover, the anticancer activity of Hal-PG-FA/DOX was detected by Cell Counting Kit-8 (CCK8) and flow cytometry (FCM). In vitro cytotoxicity assay preliminarily proved that the Hal-PG-FA/DOX had a more significant inhibitory effect than the free DOX. The results of flow cytometry showed that apoptosis rate on HeLa cells was enhanced by Hal-PG-FA/DOX. All these results showed that folate-PG modified halloysite is an excellent nano anticancer drug carrier in cancer therapy.

Polyglycerol Grafting Shields Nanoparticles from Protein Corona Formation to Avoid Macrophage Uptake.

Upon contact with biofluids, proteins are quickly adsorbed onto the nanoparticle (NP) surface to form a protein corona, which initiates the opsonization and facilitates the rapid clearance of the NP by macrophage uptake. Although polyethylene glycol (PEG) functionalization has been the standard approach to evade macrophage uptake by reducing protein adsorption, it cannot fully eliminate nonspecific uptake. Herein, polyglycerol (PG) grafting is demonstrated as a better alternative to PEG. NPs of various size and material were grafted with PG and PEG at 30, 20, and 10 wt % contents by controlling the reaction conditions, and the resulting NP-PG and NP-PEG were characterized qualitatively by IR spectroscopy and quantitatively by thermogravimetric analysis. Their resistivity to adsorption of the proteins in fetal bovine serum and human plasma were compared by polyacrylamide gel electrophoresis, bicinchoninic acid assay, and liquid chromatography-tandem mass spectrometry, giving a consistent conclusion that PG shields protein adsorption more efficiently than does PEG. The macrophage uptake was assayed by transmission electron microscopy and by extinction spectroscopy or inductively coupled plasma mass spectrometry, revealing that PG avoids macrophage uptake more efficiently than does PEG. In particular, a NP coated with PG at 30 wt % (NP-PG-h) prevents corona formation almost completely, regardless of NP size and core material, leading to the complete evasion of macrophage uptake. Our findings demonstrate that PG grafting is a promising strategy in nanomedicine to improve anti-biofouling property and stealth efficiency in nanoformulations.

Quantitative investigation of the interaction between proteins and charged functional groups on the polyglycerol-grafted nanodiamond surface

Interaction at the interface between protein and nanoparticle (NP) surface is of fundamental importance in nanomedicine, because protein corona formation on the NP surface affects the biological identity of the NP. Recently, polyglycerol (PG) has been revealed as a protein free coating for NPs, enabling us to evaluate the net affinity of the specific functional group on the “transparent” NP surface to protein. Herein, PG grafted nanodiamond (ND-PG) was functionalized with carboxyl and amino groups at various densities, and their interaction with proteins including lysozyme (LYS), bovine serum albumin (BSA) and γ-globulin (γ-GLO) were investigated in phosphate buffer saline (PBS). The results show that the carboxylate (-COO–) and ammonium (-NH3+) groups interact exclusively with positively charged LYS, and negatively charged BSA and γ-GLO, respectively, and that the interaction becomes stronger as the functional group density increases. Moreover, the association constants (K) between BSA and the ammonium group on ND-PG are determined and found to correlate linearly with the ammonium group density. The slopes in the linear relationship are proposed to be indices to represent the interaction strength of ammonium group to BSA, enabling the quantitative comparison of the affinity between proteins and various NP surface coatings.

Antifouling Properties of Dendritic Polyglycerols against Marine Macrofouling Organisms.

Dendritic polyglycerols (PGs) were synthesized and postmodified by grafting of poly(ethylene glycol) (PEG) and polypropylene glycol (PPG) diglycidyl ether groups, and their antifouling and fouling-release properties were tested. Coating characterization by spectroscopic ellipsometry, contact angle goniometry, attenuated total internal reflection-Fourier transform infrared spectroscopy (ATR-FTIR), and atomic force microscopy showed brushlike morphologies with a high degree of microscale roughness and the ability to absorb large amounts of water within seconds. PGs with three different thicknesses were tested in laboratory assays against settlement of larvae of the barnacle Balanus improvisus and against the settlement and removal of zoospores of the alga Ulva linza. Very low coating thicknesses, e.g., 11 nm, reduced the settlement of barnacles, under static conditions, to 2% compared with 55% for an octadecyltrichlorosilane reference surface. In contrast, zoospores of U. linza settled readily but the vast majority were removed by exposure to a shear force of 52 Pa. Both PEG and PPG modification increased the antifouling properties of the PG films, providing a direct comparison of the ultralow fouling properties of all three polymers. Both, the modified and the nonmodified PGs are promising components for incorporation into amphiphilic fouling-resistant coatings.

Preparation of polyglycerol mediated superparamagnetic graphene oxide nanocomposite and evaluation of its adsorption properties on tetracycline

In this paper, we synthesized a polyglycerol(PG)-mediated superparamagnetic graphene oxide nanocomposite called MGON, consisting of PG-modified superparamagnetic iron oxide nanoparticles (SPION) covalently bonded to PG-functionalized graphene oxide (GO). MGON exhibits better dispersibility and colloidal stability in aqueous solution than the magnetic graphene oxide reported in the literature. The physicochemical properties of MGON were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), and UV-vis spectroscopy. Applied to the adsorption of tetracycline (TC) in aqueous solution as an adsorbent, the MGON showed excellent adsorption performance with the maximum adsorption capacity of 684.93mg/g at 298K. Adsorption kinetics and isotherm results indicate that the adsorption process conforms to the pseudo-second-order kinetics and Langmuir isotherm models. Adsorption thermodynamics has confirmed that the adsorption process of TC on MGON is spontaneous and endothermic. With the increase of temperature, the adsorption capacity of MGON increases continuously, and the adsorption capacity of MGON is the largest when the pH value is 7. Furthermore, the π-π and cation-π interaction, amidation reaction, and hydrogen bonding can be used to explain the adsorption mechanism of TC on MGON. Desorption and regeneration experiments showed that MGON still had 67.65% regenerative performance after five cycles. Hence, MGON is a promising adsorbent in the removal of tetracycline from wastewater.

Noncovalent Functionalization of Carbon Substrates with Hydrogels Improves Structural Analysis of Vitrified Proteins by Electron Cryo-Microscopy.

In electron cryo-microscopy, structure determination of protein molecules is frequently hampered by adsorption of the particles to the support film material, typically amorphous carbon. Here, we report that pyrene derivatives with one or two polyglycerol (PG) side chains bind to the amorphous carbon films, forming a biorepulsive hydrogel layer so that the number of protein particles in the vitreous ice drastically increases. This approach could be extended by adding a hydrogel-functionalized carbon nanotube network (HyCaNet, the hydrogel again being formed from the PG-pyrene derivatives), which stabilized the protein-containing thin ice films during imaging with the electron beam. The stabilization resulted in reduced particle motion by up to 70%. These substrates were instrumental for determining the structure of a large membrane protein complex.

Phosphonylation Controls the Protein Corona of Multifunctional Polyglycerol-Modified Nanocarriers.

Nanocarriers are a platform for modern drug delivery. In contact with blood, proteins adsorb to nanocarriers, altering their behavior in vivo. To reduce unspecific protein adsorption and unspecific cellular uptake, nanocarriers are modified with hydrophilic polymers like poly(ethylene glycol) (PEG). However, with PEG the attachment of further functional structures such as targeting units is limited. A method to introduce multifunctionality via polyglycerol (PG) while maintaining the hydrophilicity of PEG is introduced. Different amounts of negatively charged phosphonate groups (up to 29 mol%) are attached to the multifunctional PGs (Mn 2-4 kg mol-1 , Ð < 1.36) by post-modification. PGs are used in the miniemulsion/solvent evaporation procedure to prepare model nanocarriers. Their behavior in human blood plasma is investigated to determine the influence of the negative charges on the protein adsorption. The protein corona of PGylated nanocarriers is similar to PEGylated analogs (on same nanocarriers), but the protein pattern could be gradually altered by the integration of phosphonates. This is the first report on the gradual increase of negative charges on nanocarriers and intriguingly up to a certain amount of phosphonate groups per nanocarrier the protein pattern remains relatively unchanged, which is important for the future design of nanocarriers.

Fast degrading elastomer stented fascia remodels into tough and vascularized construct for tracheal regeneration

Tracheal reconstruction remains a major surgical challenge, mainly owing to the scarce of resilient hollow grafts with identifiable vascular pedicle in humans. In this study, we developed a three-layer, elastomeric, trachea-like composite made of poly glycerol sebacate (PGS) and polycaprolactone (PCL), which presented appropriate resilient property, timely degradation and interconnected pores. C shape PCL rings fabricated with selective laser sintering (SLS) techniques are regularly positioned around porous PGS tubes and fixed by PCL electrospinning sheath. Such an elastomeric composite underwent host remodeling including rapid vascularization and tissue infiltration after fascia wrapping. With degrading of PGS, C rings well incorporated into growing fascia and lead to the formation of pedicled tracheal grafts, which attributes to the strong and resilient properties of generated hollow grafts thus enabled orthotopic transplantation in segmental tracheal defect. Progressive remodeling on such vascularized and mechanically stable grafts resulted in epithelium regeneration on luminal side as well as production of adequate amount of collagen and elastin, which warrantees the air passage during breathing. Future study employing large animal models more representative of human tracheal regeneration is warranted before clinical translation. Using fast degrading PGS combined with PCL rings represents a philosophical shift from the prevailing focus on tough grafts in airway reconstruction and may impact regenerative medicine in general.

Polyglycerol-grafted multi-walled carbon nanotubes were prepared by one-pot method and reacted with folic acid to enhanced stability in a physiological medium

ABSTRACTFor a targeted drug delivery, it was great biomedical potential, significance, importance and application value to construct a colloidal-chemistry stable nanocomposite. Functionalized multi-walled carbon (MWNTs-OX) has attracted considerable attention due to the unique atomic structure, strong cell membrane penetration, specific surface area and low toxicity. It has also been used widely for targeted drug delivery as an ideal nanocomposite. In this paper, a facile one-pot strategy to MWNTs-OX with hyperbranched polyglycerol (PG) by surface-initiated ring-opening polymerization of glycidol was used to form MWNTs-OX-PG. Then, the partial periphery of PG layer was converted to carboxy groups and covalently linked to FA to form MWNTs-OX-PG-COOH-FA. Meanwhile, the properties of MWNTs-OX, MWNTs-OX-PG, MWNTs-OX-PG-COOH and MWNTs-OX-COOH-FA were characterized by Fourier transform infrared (FT-IR), Ultraviolet-visible spectrophotometry (UV), Thermogravimetric analysis (TGA), Scanning transmission electron microscopy (STEM) and elemental analysis, and the results indicated that MWNTs-OX-PG-COOH-FA preformed excellent dispersity, interface stability and long-term storage. This paper opened up a new strategy to rational design folic acid-functionalized MWNTs-OX-PG multifunctional nanohybrids as biomaterials.

Magnetofluorescent nanohybrid comprising polyglycerol grafted carbon dots and iron oxides: Colloidal synthesis and applications in cellular imaging and magnetically enhanced drug delivery.

Multifunctional nanohybrids are attracting increasing attention for potential biomedical applications such as bioimaging and drug delivery due to their combined advantages of individual components. However, challenges in the improvement of their synthesis and colloidal stability to facilitate practical biomedical applications still remain. In this work, we report an efficient synthetic approach to fabricate magnetofluorescent nanohybrid (IO-PG-CD) comprising fluorescent carbon dots (CDs) and magnetic iron oxide nanoparticles (IOs) through polyglycerol (PG) mediated covalent linkage in aqueous media. CDs and IOs are first grafted with PG layer, and then functionalized with carboxyl and amino groups, respectively. The resulting CD-PG-COOH and IO-PG-NH2 handled as simple chemical compounds are integrated through EDC/NHS crosslinking to obtain the desired IO-PG-CD nanohybrid. The unprecedented hydrophilicity of PG layer endows IO-PG-CD nanohybrid with excellent colloidal stability in various physiological media, facilitating biomedical applications in vitro and in vivo. IO-PG-CD nanohybrid exhibits low cytotoxicity and its uptake by cells can be obviously enhanced by external magnetic attraction. The internalized IO-PG-CD nanohybrid emits multicolor fluorescence as observed by confocal fluorescence microscopy, demonstrating much better photostability than the nanoparticle labeled with organic dye. Taking advantage of enormous chelating carboxyl groups on the surface of IO-PG-CD nanohybrid, platinum-based anticancer drug was loaded on the surface (IO-PG-CD/Pt) through complexation and delivered into cancer cells in a magnetically enhanced manner, killing the cancer cells efficiently in vitro. Moreover, in vivo cancer therapy indicates that the external magnetic attraction also obviously improves the anticancer efficacy of IO-PG-CD/Pt in HeLa subcutaneous xenografts.

Fouling-Release Properties of Dendritic Polyglycerols against Marine Diatoms

Dendritic polyglycerols (PGs) were grafted onto surfaces using a ring-opening polymerization reaction, and the fouling-release properties against marine organisms were determined. The coatings were characterized by spectroscopic ellipsometry, contact angle goniometry, ATR-FTIR, and stability tests in different aqueous media. A high resistance toward the attachment of different proteins was found. The PG coatings with three different thicknesses were tested in a laboratory assay against the diatom Navicula incerta and in a field assay using a rotating disk. Under static conditions, the PG coatings did not inhibit the initial attachment of diatoms, but up to 94% of attached diatoms could be removed from the coatings after exposure to a shear stress of 19 Pa. Fouling release was found to be enhanced if the coatings were sufficiently thick. The excellent fouling-release properties were supported in dynamic field-immersion experiments in which the samples were continually exposed to a shear stress of 0.18 Pa.

Synthesis and characterization of polyglycerol coated superparamagnetic iron oxide nanoparticles and cytotoxicity evaluation on normal human cell lines

Superparamagnetic iron oxide nanoparticles (SPIONs) are considered as interesting nano-carriers for cancer detection and treatment. As promising reagents for biomedical applications they need surface modifications and polyglycerol has shown suitable characteristics as a coating agent in this regard. Synthesis and characterization of SPIONs and polyglycerol coated SPIONs (PG-SPIONs) as well as evaluation of cytotoxic effects on normal human cell lines (HEK293 and MCF10A) was the aim of present study. The effect of SPIONs and PG-SPIONs on these cell lines was evaluated by measuring the cell viability, apoptosis, expression of apoptosis-associated proteins and caspase-3 activity. Characteristics of nanoparticles were determined by TEM, FTIR, VSM and XRD. Mean size of SPIONs and PG-SPIONs were found to be 5.4 ± 0.75 nm and 17.9 ± 2.85 nm, respectively. XRD result demonstrates that the nanoparticles are Fe3O4 with highly crystalline particles and their surface modification by Polyglycerol (PG) and superparamagnetic behavior was confirmed by FTIR and VSM. The surface coating significantly increased cell viability, attenuated apoptosis, promoted expression of Bax and P53 and reduced Bcl2 protein expression and caspase-3 activity. In conclusion, these results indicates that surface coating of SPIONs with PG can decrease SPIONs-induced cell injury in normal human cells, suggesting PG-SPIONs as safe nanocarriers for application in medicine.

Highly Flexible and Conductive Glycerol-Doped PEDOT:PSS Films Prepared Under an Electric Field

Poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) films doped with several sugar alcohols, viz. xylitol (XL), glycerol (GL), and polyglycerol (PG), at various levels have been synthesized and their thermoelectric properties studied. Among these specimens, 2.5 vol.% GL-doped films showed the best performance with electrical conductivity σ, Seebeck coefficient S, and power factor S2σ at room temperature reaching 1040 S/cm, 19 μV/K, and 37 μW/m-K2, respectively. Next, we synthesized films under an electric field Epr for the purpose of crystal growth. GL-doped films showed σ enhancement with increase of Epr. The highest σ value of 1300 S/cm was attained at Epr = 4 kV/cm. S and thermal conductivity κ values were almost independent of Epr. The ZT value was calculated to be between 0.017 and 0.101 at room temperature. We also examined film flexibility. High flexibility was achieved on GL doping, and it was not deteriorated when synthesized under an electric field.

Synthesis of polyglycerol mediated covalent construction of a core‐satellite superparamagnetic mesoporous carbon nanocomposite: application on dye adsorption

AbstractBACKGROUNDIn this work, we used a polyglycerol (PG) mediated covalent linkage to produce a core‐satellite superparamagnetic nanocomposite, termed MMCN composed of superparamagnetic iron oxide nanoparticles (SPIONs) covalently bound to core mesoporous carbon nanoparticle (MCN). Magnetic separation is a very useful method for removing and recycling pollutant in the water by applying external magnetic field. SPIONs were good candidates that guide the MCN to desired sites using a magnet to achieve water purification. This method was used as an adsorbent for removal of methylene blue (MB) from aqueous solutions.RESULTSThe magnetism of the MMCN nanocomposites was sufficient to be magnetically separated by applying a magnetic field. The MMCN was found to be a sufficient dye adsorbent with a maximum adsorption capacity of 250 mg g−1. Furthermore, the adsorbent could be regenerated and reused effectively by ethanol solution and allowed the treatment of wastewater contamination by MB in industry.CONCLUSIONThe MMCN nanocomposites obtained high dispersibility, superparamagnetic and good recyclability through PG mediated covalent linkage. The optical properties of these multifunctional nanocomposites indicate that they can be used for highly efficient removal of water pollutants such as dyes, that can be quickly separated by applying a magnetic field. © 2018 Society of Chemical Industry

Preparation and evaluation of poly glycerol sebacate/poly hydroxy butyrate core‐shell electrospun nanofibers with sequentially release of ciprofloxacin and simvastatin in wound dressings

Biodegradable wound dressing of poly glycerol sebacate/poly hydroxy butyrate was fabricated via the coaxial electrospinning process. Simvastatin and ciprofloxacin were loaded in the core and shell of the fibers, respectively. Scanning electron microscopy and transmission electron microscopy images showed a uniform core/shell structure. Introducing drugs into the polymers would cause the dressing samples to become more hydrophilic and degradation to occur faster. Drugs release would face no interventions, in which, approximately 60% of ciprofloxacin was released during the first 24 hours. Simvastatin exhibited a slower and controlled release behavior, with its release peak recorded after 2 days. The drug‐containing samples showed a proper bactericidal activity against both Gram‐positive and Gram‐negative bacteria. It may be concluded that the drug‐laden wound dressing fabricated in this study is capable of releasing the 2 drugs sequentially and that it is the ideal conditions for controlling infections and reducing wound healing duration.