Polycaprolactone Layer Research Articles

4D printing of bilayer tubular structure with dual‐stimuli responsive based on self‐rolling behavior

AbstractSelf‐rolling allows the bilayer to transform into a 3D structure in response to specific external stimulation, such as heat, humidity, ions, etc. Herein, we report a 4D printing bilayer with a top sodium alginate layer and bottom polycaprolactone layer that could be rolled up to a tubular structure upon exposure to heat and Ca2+ solution stimulation. The discrepancy in the swelling and thermal‐responsiveness between alginate and polycaprolactone induced the self‐rolling under different stimuli. The self‐rolling behavior of the bilayer depends on the aspect ratio, thickness ratio of the bilayer film, the pattern, and external stimuli. Thus, a tailorable surface of the self‐rolled tube was obtained by tuning the bilayer parameter and the stimuli medium to meet varied demands. This controllable shape changing provides a strategy for the preparation of well‐defined tubular structures. Besides, the biocompatibility of bilayer film suggests the potential application in the field of biomedical device such as vascular stent.

Perivascular application of sirolimus multilayer nanofibrous mat for prevention of vascular stenosis: Preparation, In vitro characterization, and In vivo efficacy evaluation

Graft stenosis, occurring after coronary artery bypass surgery (CABG), diminishes the efficacy and long-term patency of vascular interventions. Multilayer nanofibers (NFs) are developed to provide localized controlled release of sirolimus to prevent vascular stenosis, as well as limit drug exposure to other organs. NFs are composed of a mid-layer of drug and polycaprolactone (PCL), a bioadhesive layer of PCL and collagen, and a backing layer of PCL. NFs are characterized in vitro regarding morphology, mechanical strength, contact angle, water uptake, drug content, and drug release behavior. The average fiber diameter is around 300–500 nm. Sirolimus entrapment is confirmed by drug content, FTIR, and XRD. It is found that sirolimus is released from multilayer NFs in a sustained manner with about half of the payload released over one week. Sirolimus multilayer NFs are implanted in the rat carotid artery after inducing vascular injury. Histological, immunohistochemical (α-SMA, Ki-67, and CD31), and in vivo imaging analyses reveal that the administration of sirolimus multilayer NFs causes significant inhibition of intimal hyperplasia in the rat carotid injury model compared to the control groups and drug suspension. The obtained results reveal that the sirolimus multilayer nanosystem could be a promising carrier for local vascular drug delivery.

3D printed hydrogel/wesselsite-PCL composite scaffold with structural change from core/shell fibers to microchannels for enhanced bone regeneration

Corresponding to the process of bone formation, three-dimensional (3D) scaffolds should provide adaptive structural cues and microenvironment for bone repair at different stages. Herein, we fabricate a core-shell fiber scaffold by coating a layer of polycaprolactone (PCL)/SrCuSi4O10 (wesselsite, CS) on 3D printed hydrogel scaffolds. The core/shell scaffold provided enhanced mechanical support for the defect at the initial stage. Then, the degradation of hydrogels resulted in the transformation of core/shell fiber structure (hydrogel/PCL + CS) to interconnected microchannels (PCL/CS hollow channel), which provided increasing space and clear architectural cues for promoting bone formation and vascularization. Simultaneously, the chemokine stromal cell-derived factor-1α (SDF-1α) loaded in hydrogels achieved sustained release in the initial two weeks to facilitate the recruitment of bone marrow stromal cells (BMSCs) to defect. Subsequently, the degradation of CS nanomaterials yielded the sustained release of bioactive ions (Si, Sr and Cu), promoting osteogenesis and angiogenesis. The in vivo data showed that the prepared scaffolds exhibited enhanced bone repair capacity with abundant new bone formation and blood vessels ingrowth in the defect. Thus, this designed system shows great potential for bone tissue engineering application.

Preparation of anticorrosion, biocompatible and antibacterial dicalcium phosphate dihydrate/polycaprolactone-titania composite coating on Mg alloy

As a new implantable biomaterial, magnesium (Mg) alloy has a broad application prospect. However, it is urgent to solve the disadvantage of rapid degradation. In this work, a composite coating with flaky dicalcium phosphate dihydrate (DCPD) as the bottom layer and polycaprolactone (PCL) incorporated with titania (TiO2) as the sealing layer was synthesized by electrodeposition and spin coating. Due to the sealing effect of the PCL layer and the blocking effect of TiO2 nanoparticles on the corrosive solution, the corrosion resistance of the composite coating sample is significantly improved, and its impedance could reach 628 times that of Mg alloy, and the total hydrogen evolution amount of the composite coating is only 1/19 of that of Mg alloy after immersion for 14 days. Besides, the addition of TiO2 not only further improved the biocompatibility of the sample, but also endowed it with excellent bacteriostasis, which was expected to meet the standard of clinical implantation.

Asymmetric Electrospun Nanofiber Composed Of Polycaprolactone, Chitosan, and Curcumin To Promote Chronic Wound Healing

Chronic wounds are a growing medical issue around the world, with 2.4 - 4.5 million people afflicted in the United States alone. The condition currently makes up 2-3% of healthcare costs for developed countries, and this number is expected to increase as chronic wound-causing problems, like diabetes, grow in prevalence. Due to the lack of effective wound dressings, chronic wounds face a higher risk for bacterial infection and express high morbidity and mortality rates. Many current dressings are homogeneous and fail to account for the complexities of the different layers of skin. Alternatively, asymmetric electrospun nanofibers have a bilayer design that corresponds to the skin’s dermis and epidermis. We intend to demonstrate that an asymmetric electrospun nanofiber composed of polycaprolactone (PCL), chitosan (CS), and curcumin (Cur) can be utilized as a chronic wound dressing. These three biodegradable and biocompatible components were applied in an asymmetric design to mimic the protective epidermis and porous dermis. Upon electrospinning our asymmetric nanofiber and running it through a scanning electron microscope, we found that our hydrophobic PCL layer had a low porosity (52.16%) and thin nanofibers (281.82 nm), while our hydrophilic PCL/CS/Cur layer had a high porosity (61.18%) and thick nanofibers (425.54 nm). Our asymmetric nanofiber was also more effective at resisting bacterial permeation than the homogeneous PCL nanofiber. Our results highlight the superiority of asymmetric membranes for resisting bacterial infection and suggest that with further experimentation, we can establish our nanofiber as a viable wound dressing.

Janus fibre/sponge composite combined with IOPNs promotes haemostasis and efficient reconstruction in oral guided bone regeneration

Placing a barrier membrane between an alveolar bone wound and gingival soft tissue is a common and effective method to prevent fibroblast invasion and promote new bone formation. However, the combined use of a barrier membrane with bone-forming substitutes remains a challenge for dentists during surgery. Thus, a Janus fibre/sponge composite combining iron oxide nanoparticles (IONPs, γ-Fe2O3) was fabricated to prevent epithelial invasion and promote alveolar reconstruction. In the scaffold, a poly (lactic-co-glycolic acid)/polycaprolactone (PP) electrospun layer was covalently bound with a chitosan sponge containing γ-Fe2O3 by polydopamine. The resilient chitosan sponge can easily adhere to the wound surface and encompass haemostatic capability by swelling and forming blood clots to block bleeding. The introduction of IONPs promoted the osteogenesis of rBMSCs, as shown by ALP analysis and cytokine assay. The PP layer maintained its structure integrity and prevented epithelial cells from invading into blood clots or fibroblasts from penetrating through the critical pore size. Assessment with a rat model having one-sided calvarial bone injury further confirmed the effectiveness of Janus scaffolds in facilitating the bone regeneration in the postoperative areas.

Blood-Vessel-Inspired Hierarchical Trilayer Scaffolds: PCL/Gelatin-Driven Protein Adsorption and Cellular Interaction.

Fabrication of scaffolds with hierarchical structures exhibiting the blood vessel topological and biochemical features of the native extracellular matrix that maintain long-term patency remains a major challenge. Within this context, scaffold assembly using biodegradable synthetic polymers (BSPs) via electrospinning had led to soft-tissue-resembling microstructures that allow cell infiltration. However, BSPs fail to exhibit the sufficient surface reactivity, limiting protein adsorption and/or cell adhesion and jeopardizing the overall graft performance. Here, we present a methodology for the fabrication of three-layered polycaprolactone (PCL)-based tubular structures with biochemical cues to improve protein adsorption and cell adhesion. For this purpose, PCL was backbone-oxidized (O-PCL) and cast over a photolithography-manufactured microgrooved mold to obtain a bioactive surface as demonstrated using a protein adsorption assay (BSA), Fourier transform infrared spectroscopy (FTIR) and calorimetric analyses. Then, two layers of PCL:gelatin (75:25 and 95:5 w/w), obtained using a novel single-desolvation method, were electrospun over the casted O-PCL to mimic a vascular wall with a physicochemical gradient to guide cell adhesion. Furthermore, tensile properties were shown to withstand the physiological mechanical stresses and strains. In vitro characterization, using L929 mouse fibroblasts, demonstrated that the multilayered scaffold is a suitable platform for cell infiltration and proliferation from the innermost to the outermost layer as is needed for vascular wall regeneration. Our work holds promise as a strategy for the low-cost manufacture of next-generation polymer-based hierarchical scaffolds with high bioactivity and resemblance of ECM’s microstructure to accurately guide cell attachment and proliferation.

Biodegraded PCl and gelatin fabricated vascular patch in rat aortic and inferior vena cava angioplasty.

Novel synthetic prosthesis materials for patch angioplasty are continuously under development and optimization. When a nonwoven-based gelatin membrane is coupled with an electrospun layer of polycaprolactone (PCL), these biohybrid polymer membranes (BHMs) possess higher mechanical properties in aqueous environments. We hypothesized that BHMs can also be used as vascular patches, and we tested our hypothesis in a rat IVC venoplasty and aortic arterioplasty model. Patch venoplasty and arterioplasty were performed in SD rats (200g), the patches were harvested at day 14, and samples were analyzed by immunohistochemistry and immunofluorescence. The BHM patches were almost degraded, with few parts remaining after 14days. There was a line of CD34- and nestin-positive cells on the endothelium, with some cells were CD34 and nestin dual-positive, macrophages and leukocytes also participated in the patch healing process. There were PCNA-positive cells in the neointima and peri-patch area, with some cells were also PCNA and α-actin dual-positive. Arterial neointimal endothelial cells were Ephrin-B2- and dll-4-positive, and venous neointimal endothelial cells were Eph-B4- and COUP-TFII-positive. BHM shares a similar healing process like other patch materials, and BHM may have potential applications in vascular surgery.

Development of a novel polycaprolactone based composite membrane for periodontal regeneration using spin coating technique

Guided bone regeneration (GBR) is known to prevent the development of soft tissue on the defect sites as well as support the new bone formation on the other end. In the present study, we developed a multilayer biodegradable membrane for GBR applications. The multilayer membrane is primarily composed of β-tricalcium phosphate (TCP), polycaprolactone (PCL), and hyaluronic acid (HA), prepared by the spin-coating method. The triple layer system has PCL-TCP composite layer on top, a PCL layer in the middle, and PCL-HA as the bottom layer. The characterization of the PCL-TCP/PCL/PCL-HA by various techniques such as SEM, EDS, XRD, and FT-IR supported the uniform formation of the triple layers with an overall thickness of ∼ 72 µm. Multilayer composite membrane showed excellent physical parameters; neutral pH, high hydrophilicity, high swelling rate, low degradation rate, and high apatite formation after immersion in simulated body fluid (SBF) for 14 days. The multilayer membrane also exhibited biocompatibility which is evident by MTT assay and confocal images. The results suggested that the multilayer composite membrane has the potential for GBR applications.

Hydrophobization of hydrophilic alginate/chitosan PEC surfaces

AbstractAlginate and chitosan are biocompatible polysaccharides that are often combined as polyelectrolyte complexes (PECs) for the development of biomaterials. These PECs are interesting as wound dressings, among other uses. The properties of such devices depend on their surface characteristics, however. Herein we propose a method to hydrophobize highly hydrophilic alginate/chitosan PECs by initial chemical grafting of polycaprolactone (PCL) or polylactic acid, using hexane diamine or ethylenediamine as linkers, followed by a drop casting covering step. This resulted in increased adhesion between the hydrophobic layer and the PEC, when compared to direct casting. The materials obtained were evaluated as potential biomaterials by analyzing the hydrophilic properties of their surface, swelling, enzymatic degradation, and impermeability. The results revealed that hydrophobization was effective but decreased the swelling abilities of PECs, which still remained interesting (~1000%) for wound dressing applications. However, the PCL layer was not resistant to the enzymatic environment, while PLA showed impermeabilization of the PECs.

The modification of the wetting of polycaprolactone nanofibre layers via alternating current spinning

The study addresses the modification of the wetting of fibrous layers of polycaprolactone via alternating current spinning. The production of the fibre layers considered in the study was initiated using a function generator. The shifting of the offset to the limits of the transmitted amplitude resulted in the production of wettable fibrous layers with high surface energy values. The study revealed that the frequency of alternating spinning affects the surface energy value. Thus, by changing the alternating spinning frequency, it is possible to change the wettability of the produced fibre layers. The study concluded that it is possible to predict the contact angle via the application of the Kwok-Neumann model, as well as the use of the surface tension values of the gelatin hydrogel and the surface energies of the fibre layers produced.

Development of chitosan/cycloolefin copolymer and chitosan/polycaprolactone active bilayer films incorporated with grape seed extract and carvacrol

Chitosan (CH) bilayer films were obtained by casting polycaprolactone (PCL) or cycloolefin copolymer (COC) onto the CH film surface. Active components, such as grape seed extract (GSE, 5%, w/w) and carvacrol (CV, 10%, w/w), were incorporated into the bilayers. Film samples were characterized as the release behavior of CV in ethanol, antioxidant activity, water vapor permeability (WVP), tensile properties, and optical characteristics. The contact angles of COC and PCL chloroform solutions on the CH-based film surface were also analyzed to evaluate the potential wettability of CH films with PCL or COC solutions. A lower release rate was observed in COC-based bilayer films when compared to PCL-based bilayers. Film samples including GSE and CV showed radical scavenging activity, reducing the radical between 10—15%. The PCL or COC layers on CH improved the WVP, while GSE also negatively affected WVP. The combination of GSE and CV in the bilayer film formulations enhanced the films’ tensile properties. All film samples showed an internal transmittance value of around 80%.

3D printed hydrogel/PCL core/shell fiber scaffolds with NIR-triggered drug release for cancer therapy and wound healing

Hydrogel based scaffolds with the ability of on-demand drug delivery gained increasing interests for localized cancer therapy and tissue engineering application. However, most drug-loaded hydrogels are generally not suitable for long-term drug delivery, because of the uncontrolled diffusion of drugs from the swollen hydrogels. Therefore, in this study, a core/shell fiber scaffold was fabricated by coating a homogeneous layer of polycaprolactone (PCL) on the 3D printed alginate-gelatin hydrogel scaffolds. The PCL coatings could reduce the free diffusion of drugs from the core gels. Subsequently, polydopamine (PDA) was coated on the Gel/PCL core/shell scaffolds, endowing the scaffolds with great photothermal effects. Thus, near-infrared (NIR) laser triggered on-demand drug release was realized in this system due to the thermally induced sol-gel transition of the core gels. The released drugs (doxorubicin) and photothermal therapy could effectively prohibit or ablate tumor in vitro and in vivo. Additionally, the Gel/PCL/PDA core/shell scaffold could serve as platform for promoting wound healing. Therefore, the reported Gel/PCL/PDA core/shell scaffolds have the potential for application in localized cancer therapy and tissue regeneration. Especially for those cancer patients suffering surgical resection, the scaffolds could be implanted in the resection site to kill the residual or recurrent cancer cells, as well as to repair the tissue defects caused by surgery. Statement of significanceThis paper reported a facile strategy to realize stimuli-triggered on demand drug release in vitro and in vivo. Polycaprolactone (PCL) and polydopamine were sequentially deposited on the surface of 3D printed drug-loaded alginate/gelatin scaffold. PCL encapsulation could effectively reduce the free diffusion of drugs from the core hydrogel, achieving sustained drug release. Polydopamine with good photothermal effects endowed the scaffold with stimuli-triggered drug release in response to near-infrared (NIR) laser irradiation. This scaffold could be applied for localized cancer therapy and tissue regeneration. Especially for those cancer patients suffering surgical resection, the scaffolds could be implanted in the resection site to kill the residual or recurrent cancer cells, as well as to repair the tissue defects caused by surgery.

Features of a simvastatin-loaded multi-layered co-electrospun barrier membrane for guided bone regeneration.

A novel tri-layer membrane consisting of polycaprolactone (PCL) fibrous sheets and structured nanofibers with a gelatin (Gt) shell and a simvastatin-containing PCL core (PCL-Gt/PCL-simvastatin membrane) was prepared. The soft external layer comprised of Gt/PCL-simvastatin, the external layer of PCL and the middle layer of both microfilaments, interwoven together. The membrane was designed to promote osteoinduction and act as a barrier against cells but not against water and molecules in order to promote guided bone regeneration. The structure of the membrane was characterized by scanning electronic microscopy. The in vitro release rates of simvastatin over 32 days were determined by high-performance liquid chromatography. For in vitro biological assays, bone marrow mesenchymal stem cells and human fibroblasts were cultured on the different surfaces of the membrane. Cell adhesion, proliferation, distribution, and differentiation were examined. For in vivo testing, cranial defects were created in rabbits to assess the amount of new bone formed for each membrane. The results revealed that membranes with multi-layered structures showed good cell viability and effective osteoinductive and barrier properties. These results suggest that the novel multi-layered PCL-Gt/PCL-simvastatin membranes have great potential for bone tissue engineering.

Designing Biodegradable and Active Multilayer System by Assembling an Electrospun Polycaprolactone Mat Containing Quercetin and Nanocellulose between Polylactic Acid Films.

The design of multilayer systems is an innovative strategy to improve physical properties of biodegradable polymers and introduce functionality to the materials through the incorporation of an active compound into some of these layers. In this work, a trilayer film based on a sandwich of electrospun polycaprolactone (PCL) fibers (PCLé) containing quercetin (Q) and cellulose nanocrystals (CNC) between extruded polylactic acid (PLA) films was designed with the purpose of improving thermal and barrier properties and affording antioxidant activity to packaged foods. PCLé was successfully electrospun onto 70 µm-thick extruded PLA film followed by the assembling of a third 25 µm-thick commercial PLA film through hot pressing. Optical, morphological, thermal, and barrier properties were evaluated in order to study the effect of PCL layer and the addition of Q and CNC. Bilayer systems obtained after the electrospinning process of PCL onto PLA film were also evaluated. The release of quercetin from bi- and trilayer films to food simulants was also analyzed. Results evidenced that thermal treatment during thermo-compression melted PCL polymer and resulted in trilayer systems with barrier properties similar to single PLA film. Quercetin release from bi- and trilayer films followed a similar profile, but achieved highest value through the addition of CNC.

Development of Chitosan and Polycaprolactone Based Trilayer Biocomposite Films for Food Packaging Applications

Chitosan (CH) films were obtained by casting method and sandwiched between 2 layers of polycaprolactone (PCL), which were formed by compression molding, to form trilayers. CH films were also incorporated with grape seed extract (G) (15%, w/w) and/or nanocellulose (N) (1-5%, w/w). The tensile properties, transmittance, opacity, water vapor permeability (WVP), antimicrobial activity, and release behavior of trilayers were determined. The elastic modulus (EM) of trilayer films were not significantly affected by the N content, while higher N concentrations resulted in higher tensile strength (TS) values. The incorporation of G led to higher elongation values and resulted in lower EM and TS values. Film samples, including N, presented lower WVP values, whereas higher WVP and water solubility values were obtained with G inclusion (p<0.05). L* and transmittance values increased with the increasing N content while the opacity values decreased (p<0.05). Furthermore, films added G showed significantly higher a* and b* values. The addition of N caused slower release of G from CH films through the selected food simulants. The obtained trilayer films also inhibited selected main pathogenic bacteria. The fabrication of PCL and CH films in the trilayer form enhanced the properties of CH and made these films more appropriate for food packaging.

Chitosan/polycaprolactone multilayer hydrogel: A sustained Kartogenin delivery model for cartilage regeneration

Cartilage regeneration using biomaterial-guided delivery systems presents improved therapeutic efficacy of the biomolecules while minimizing side effects. Here, our hypothesis was to design a multilayer scaffold of chitosan (CS) hydrogel and polycaprolactone (PCL) mat to enhance the mechanical properties, integrity and stability of CS, especially for subsequent in vivo transplantation. After conjugation of the Kartogenin (KGN) into this structure, its gradual release can promote chondrogenesis of mesenchymal stem cells (MSCs). Initially, a thin electrospun PCL layer was sandwiched between two CS hydrogels. Subsequently, KGN was superficially immobilized onto the CS matrix. The successful conjugation was confirmed by scanning electron microscopy (SEM) and infrared spectroscopy. These novel KGN-conjugated scaffolds possessed lower swelling and higher compressive modulus and showed gradual release of KGN in longer retention times. Immunofluorescent and histological staining represented more cells located in lacunae as well as more Coll2 and Sox9 positive cells on KGN-conjugated scaffolds. Gene expression analysis also revealed that SOX9, COLL2 and ACAN expression levels were higher in the presence of KGN, while COLLX expression was down-regulated, indicating a hypertrophy phenomenon with synergistic effect of TGF-β. This multilayer structure not only facilitates the effective treatment, but also provides a proper mechanical structure for cartilage engineering.

Preparation and characterization of PCL‐grafted zein film via atmospheric‐pressure cold plasma pretreatment

AbstractTo improve the water resistance property of zein film, polycaprolactone (PCL) was grafted on the zein film after atmospheric‐pressure cold plasma (ACP) pretreatment. The grafting yields of PCL ranging from 15.91% ± 0.67% to 28.95% ± 0.79% were remarkably enhanced than the untreated one (12.15% ± 0.57%; p < . 05), which indicated that ACP modification could effectively improve the grafting ability of the zein film. Fourier‐transform infrared spectrum and X‐ray diffraction patterns revealed that PCL layer had been successfully grafted and the lateral α‐helix packing was susceptible to plasma treatment. Findings from this study indicated that ACP pretreatment was an effective modification approach in zein‐based polymers for packaging application.

Topological, Mechanical and Biological Properties of Ti6Al4V Scaffolds for Bone Tissue Regeneration Fabricated with Reused Powders via Electron Beam Melting.

Cellularized scaffold is emerging as the preferred solution for tissue regeneration and restoration of damaged functionalities. However, the high cost of preclinical studies creates a gap between investigation and the device market for the biomedical industry. In this work, bone-tailored scaffolds based on the Ti6Al4V alloy manufactured by electron beam melting (EBM) technology with reused powder were investigated, aiming to overcome issues connected to the high cost of preclinical studies. Two different elementary unit cell scaffold geometries, namely diamond (DO) and rhombic dodecahedron (RD), were adopted, while surface functionalization was performed by coating scaffolds with single layers of polycaprolactone (PCL) or with mixture of polycaprolactone and 20 wt.% hydroxyapatite (PCL/HA). The mechanical and biological performances of the produced scaffolds were investigated, and the results were compared to software simulation and experimental evidence available in literature. Good mechanical properties and a favorable environment for cell growth were obtained for all combinations of scaffold geometry and surface functionalization. In conclusion, powder recycling provides a viable practice for the biomedical industry to strongly reduce preclinical costs without altering biomechanical performance.

Preparation and Characterization of Electrospun Double-layered Nanocomposites Membranes as a Carrier for Centella asiatica (L.).

A wide range of naturally derived and synthetic biodegradable and biocompatible polymers are today regarded as promising materials for improving skin regeneration. Alongside this, these materials have been explored in conjunction with different types of antimicrobial and bioactive agents, especially natural-derived compounds, to enhance their biological properties. Herein, a double-layered nanocomposite dressing membrane was fabricated with two distinct layers. A bottom layer from Chitosan-Sodium tripolyphosphate (CS-TPP) and Poly(vinyl alcohol) (PVA) containing Centella asiatica (L.) (CA) was electrospun directly over a Polycaprolactone (PCL) layer to improve the biologic performance of the electrospun nanofibers. In turn, the PCL layer was designed to provide mechanical support to the damaged tissue. The results revealed that the produced double-layered nanocomposite membrane closely resembles the mechanical, porosity, and wettability features required for skin tissue engineering. On the other hand, the in vitro drug release profile of the PCL/PVA_CS-TPP containing CA exhibited a controlled release for 10 days. Moreover, the PVA_CS-TPP_CA’s bottom layer displayed the highest antibacterial activity against Staphylococcus aureus (S. aureus) (99.96 ± 6.04%) and Pseudomonas aeruginosa (P. aeruginosa) (99.94 ± 0.67%), which is responsible for avoiding bacterial penetration while endowing bioactive properties. Finally, the 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay showed that this nanocomposite membrane was not cytotoxic for normal human dermal fibroblasts (NHDF) cells. Therefore, these findings suggest the potential use of the double-layered PCL/PVA_CS-TPP_CA as an efficient bionanocomposite dressing material.