Nanofiber Network Research Articles

An integrated experimental-computational investigation of the mechanical behavior of random nanofiber networks.

An integrated experimental-computational methodology was developed to study the mechanical behavior of random polymer nanofiber networks with controlled network structural parameters. Random nanofiber networks, comprised of continuous polyethylene oxide (PEO) nanofibers with ∼250 nm diameter and controlled mean fiber segment length, were designed with a computer algorithm and printed via near-field electrospinning. The structure of the same networks served as input to a computational model to obtain predictions of the macroscopic mechanical response. This methodology provides consistency in fabricating, testing and simulating nominally identical random fiber networks. Specimens with 500 to 5000 nanofibers were subjected to uniaxial tension and compared to modeling predictions for the network mechanical behavior. The predictions by the computational model, with inputs from the experimental network structure, the measured single PEO nanofiber properties, and the fiber crimp parameter, agreed with the experimental results both quantitatively and with respect to the dependence of the measured quantities on the network parameters. The network stiffness and strength followed a power-law scaling with the network density, with exponents 2.78 ± 0.15 and 1.59 ± 0.04, respectively, while the network stretch at failure gradually decreased with increasing network fiber density. Finally, the experimentally determined network toughness demonstrated a rather weak power-law dependence on the network fiber density (exponent of 1.18 ± 0.12).

Multifunctional cyclic biomimetic peptides: Self-assembling nanotubes for effective treatment of sepsis.

Antibiotic abuse has led to an increasingly serious risk of antimicrobial resistance, developing alternative antimicrobials to combat this alarming issue is urgently needed. Rhesus theta defensin-1 (RTD-1) is a theta-defensin contributing to broad-spectrum bactericidal activity via the mechanisms of membrane perturbation. Intriguingly, human defensin-6 (HD6), an enteric defensin secreted by Paneth cells without direct bactericidal effect, could self-assembled into fibrous networks to trap enteric pathogens for assistance of innate immunity. The direct bactericidal action of RTD-1 and the bacterial trapping of HD6 inspire a promising antimicrobial paradigm for unique antibacterial strategies. In this study, we utilized the principle of alternating arrangement of D- and L-amino acids in cyclic peptides, which endows them with the potential to self-assemble into nanotubes, mimic the antimicrobial processes of RTD-1 and HD6. We designed and synthesized five cyclic biomimetic peptides (CBPs), among these biomimetics, CBP-4, which possessed a nanotube-like structure, demonstrated the ability to directly and rapidly disrupt the cell membranes of Gram-positive S. aureus and MRSA, while also targeting the surfaces of Gram-negative E. coil using its nanofibrous network to capture bacteria, preventing invasion and migration, and indirectly killing the bacteria. Moreover, CBP-4 eliminated pathogens, inhibited excessive inflammatory responses caused by infections, and maintained immune system homeostasis in septic mice. By fully emulating the antimicrobial mechanisms of both RTD-1 and HD6, CBP-4 showed promising potential for anti-infectious therapies.

In situ osteogenic activation of mesenchymal stem cells by the blood clot biomimetic mechanical microenvironment

Blood clots (BCs) play a crucial biomechanical role in promoting osteogenesis and regulating mesenchymal stem cell (MSC) function and fate. This study shows that BC formation enhances MSC osteogenesis by activating Itgb1/Fak-mediated focal adhesion and subsequent Runx2-mediated bone regeneration. Notably, BC viscoelasticity regulates this effect by modulating Runx2 nuclear translocation. To mimic this property, a viscoelastic peptide bionic hydrogel named BCgel was developed, featuring a nanofiber network, Itgb1 binding affinity, BC-like viscoelasticity, and biosafety. The anticipated efficacy of BCgel is demonstrated by its ability to induce nuclear translocation of Runx2 and promote bone regeneration in both in vitro experiments and in vivo bone defect models with blood clot defect, conducted on rats as well as beagles. This study offers insights into the mechano-transduction mechanisms of MSCs during osteogenesis and presents potential guidelines for the design of viscoelastic hydrogels in bone regenerative medicine.

Enhanced Control of Single Crystalline Ag Dendritic Growth on Al Foil via Galvanic Displacement and Simultaneous Oxidation of D‐Glucose

A facile synthesis platform for the formation of stable single crystalline Ag dendrites is demonstrated. Using a porous electrospun polyacrylonitrile nanofiber network on Al foil as a template facilitates more uniform dendritic growth in the presence of D‐glucose. In contrast, a denser polymer network restricts the nucleation site availability on the Al foil, highlighting the critical role of the substrate. The growth formation of silver dendrites is reduced in the solution when two simultaneous processes occur: The electroreduction of Ag+ in the D‐glucose solution and galvanic displacement driven by the interaction of Ag+ with the aluminum substrate. High‐resolution transmission electron microscopy analysis shows the single crystalline nature of Ag dendrites grown from the Al substrate, revealing atomic structures with closely packed layers forming highly faulted face‐centered cubic and hexagonal close‐packed structures. The remarkable long‐term stability of Ag dendrites is primarily attributed to their single crystalline structure, with additional contributions from capping by D‐gluconic acid, as confirmed by Raman analysis. This novel approach to the generation of highly stable Ag dendrites has significant potential for applications such as surface‐enhanced Raman scattering, which has to date been considered to be very sensitive to environmental effects.

Influence of Electrostatic Interactions on the Self-Assembly of Charged Peptides.

Peptides can be designed to self-assemble into predefined supramolecular nanostructures, which are then employed as biomaterials in a range of applications, including tissue engineering, drug delivery, and vaccination. However, current self-assembling peptide (SAP) hydrogels exhibit inadequate self-healing capacities and necessitate the use of sophisticated printing apparatus, rendering them unsuitable for 3D printing under physiological conditions. Here, we report a precisely designed charged peptide, Z5, with the object of investigating the impact of electrostatic interactions on the self-assembly and the rheological properties of the resulting hydrogels. This peptide displays salt-triggered self-assembly resulting in the formation of a nanofiber network with a high β-sheet content. The peptide self-assembly and the hydrogel properties can be modified according to the ionic environment. It is noteworthy that the Z5 hydrogel in normal saline (NS) shows exceptional self-healing properties, demonstrating the ability to recover its initial strength in seconds after the removal of shear force, thus rendering it an acceptable material for printing. In contrast, the strong salt shielding effect and the ionic cross-linking of Z5 hydrogels in PBS result in the bundling of peptide nanofibers, which impedes the recovery of the initial strength post-destruction. Furthermore, incorporating materials with varied charging properties into Z5 hydrogels can alter the electrostatic interactions among peptide nanofibers, further modulating the rheological properties and the printability of SAP hydrogels.

Composite electrospun membranes from cellulose nanocrystals, castor oil, and poly(ethylene terephthalate): Air permeability, thermal stability, and other relevant properties.

The study examined the use of cellulose nanocrystals (CNCs) in poly(ethylene terephthalate) (PET)/castor oil (CO) electrospun membranes, focusing on how CNCs influenced membrane properties for aerosol filtration applications. PET membranes were fabricated using 5 wt% and 10 wt% of CNCs and 2.5 wt% CO to assess its effectiveness as a compatibilizing agent, under a solution flow rate of 25.5 μL/min, a voltage of 25 kV, and a needle-collector distance of 8 cm. Nonaligned fiber membranes featured a network of ultrafine and nanofibers, while aligned fibers had an average diameter of over 300 nm (ultrafine fibers). The PET membranes permeability parameters were applied to Forchheimer's equation. All membranes presented values of Darcian (k1)/non-Darcian (k2) permeability coefficients in the order of 10-13 m2/10-8 m, respectively, near the range reported for commercial high-efficiency particulate air filters. CNCs acted as reinforcing agents, while CO was a compatibilizing agent, improving the material's mechanical behavior. Nonaligned PET/CO/10 wt% CNC presented a storage modulus (E') 2-fold higher/tensile strength 3-fold higher than pristine PET. Aligned PET/CO/5 wt% CNC, characterized in the preferential direction of fiber alignment, had approximately an E' 42-fold higher/tensile strength 6-fold higher than the same membrane, but tested in the perpendicular alignment direction. The glass transition temperature (Tg) values of PET (90-110 °C) did not exhibit any significant impact from membrane composition or fiber alignment. This study demonstrated the promising capability of PET-CNC bio-based electrospun membranes to be used in aerosol filtration or gas-solid and liquid-solid separations.

Improving the bioactivity and mechanical properties of poly(ethylene glycol)-based hydrogels through a supramolecular support network.

Most synthetic hydrogels are formed through radical polymerization to yield a homogenous covalent meshwork. In contrast, natural hydrogels form through mechanisms involving both covalent assembly and supramolecular interactions. In this communication, we expand the capabilities of covalent poly(ethylene glycol) (PEG) networks through co-assembly of supramolecular peptide nanofibers. Using a peptide hydrogelator derived from the tryptophan zipper (Trpzip) motif, we demonstrate how in situ formation of nanofiber networks can tune the stiffness of PEG-based hydrogels, while also imparting shear thinning, stress relaxation, and self-healing properties. The hybrid networks show enhanced toughness and durability under tension, providing scope for use in load bearing applications. A small quantity of Trpzip peptide renders the non-adhesive PEG network adhesive, supporting adipose derived stromal cell adhesion, elongation, and growth. The integration of supramolecular networks into covalent meshworks expands the versatility of these materials, opening up new avenues for applications in biotechnology and medicine.

Construction of a hybrid electrocatalyst by impregnating the CuS/CdFe2O4 composite heterostructure into the carbon nanofiber network for improved electrocatalytic oxygen evolution reaction

Construction of a hybrid electrocatalyst by impregnating the CuS/CdFe2O4 composite heterostructure into the carbon nanofiber network for improved electrocatalytic oxygen evolution reaction

In Situ Modulated Nickel Single Atoms on Bicontinuous Porous Carbon Fibers and Sheets Networks for Acidic CO2 Reduction.

Carbon-supported single-atom catalysts exhibit exceptional properties in acidic CO2 reduction. However, traditional carbon supports fall short in building high-site-utilization and CO2-rich interfacial environments, and the structural evolution of single-atom metals and catalytic mechanisms under realistic conditions remain ambiguous. Herein, an interconnected mesoporous carbon nanofiber and carbon nanosheet network (IPCF@CS) is reported, derived from microphase-separated block copolymer, to improve catalytic efficiency of isolated Ni. In IPCF@CS nanostructure, highly mesoporous IPCF hinders stacking of CS that provides additional fully exposed sites and abundant bicontinuous mesochannels of IPCF facilitate smooth CO2 transport. Such unique features enable enhanced Ni utilization and local CO2 enrichment, which cannot be achieved over conventional pore-deficient and discontinuous porous carbon fibers-based supports. In situ X-ray and Infrared spectroscopy coupling constant-potential calculations reveal the dynamic distortion of the planar Ni-N4 to an out-of-plane configuration with expanded Ni-N bond during operating CO2 electroreduction. The potential-driven low-valance-state Ni-N4 possesses enhanced intrinsic electrokinetics for CO2 activation and CO desorption yet inhibiting hydrogen evolution. The favorable electronic and interfacial reaction environments, resulted from the in situ tailored Ni site and IPCF@CS support, achieve an FE of near 100% at 540mAcm-2, a TOF of 55.5 s-1, and a SPCE of 89.2% in acidic CO2-to-CO electrolysis.

A Recombinant Human Collagen and RADA-16 Fusion Protein Promotes Hemostasis and Rapid Wound Healing.

In this study, we designed a fusion protein, rhCR, by combining human collagen with the self-assembling peptide RADA-16 using genetic engineering technology. The rhCR protein was successfully expressed in Pichia pastoris. The rhCR can self-assemble into a three-dimensional nanofiber network under physiological conditions. The lyophilized rhCR sponge exhibited high elasticity modulus and stable swelling properties. In vitro experiments confirmed that the rhCR had good biocompatibility and could significantly promote the adhesion, proliferation, and migration of fibroblasts (L929), upregulating the expression of genes such as Vim, Fgf, Vegf, and Tgf-β3 in L929 cells. When applied to a mouse liver hemorrhage model, rhCR hemostatic sponges rapidly formed nanofibers on the ruptured liver surface, activated platelet CD62P, and significantly reduced blood loss and bleeding duration compared to the recombinant human collagen (rhCol) alone. Furthermore, the rhCR application markedly accelerated wound healing in a mouse full-thickness skin defect model, with the wound healing rate in the rhCR group being 2.6 times that of the untreated group and 1.7 times that of the rhCol group on day 6 postinjury. Histological and immunofluorescence analyses revealed that the rhCR promoted collagen deposition and epidermal regeneration and improved the quality of skin tissue repair by stimulating tissue cells to produce cytokines, growth factors, and immune factors through immunological regulation. The rhCR fusion protein combines the advantages of collagen and RADA-16, overcoming the limitations of their separate use in hemostatic and tissue engineering applications. This biomaterial and its design idea hold promise for a variety of regenerative applications.

Multiscale Structural Strong yet Tough Triboelectric Materials Enabled by In Situ Microphase Separation

AbstractLightweight green polymer materials with exceptional toughness, high strength, and excellent ductility represent ideal candidates for enabling next‐generation sustainable flexible electronics. However, the conflicting properties of material strength and toughness present a significant challenge in achieving an optimal combination of both attributes. In this study, a strong yet tough polymeric triboelectric material is prepared by constructing a multiscale reinforced network based on a nonsolvent‐induced microphase separation strategy. The synergistic enhancement of strength and toughness is achieved by reinforcing non‐covalent interactions within the polymer and constructing nanofibrous networks. The resulting triboelectric materials exhibited remarkable fracture toughness (78.6 MJ m−3), high tensile strength (42.5 MPa), an improvement in triboelectric output (71%), and promising recyclability. The integrated triboelectric wearable sensor maintained robust output signals. This study provides a novel solution for coordinating the conflicts between strength and toughness in heterogeneous polymer materials, showing significant potential in expanding their applications in flexible electronics and self‐powered sensing technologies.

Broad‐spectrum corrosion‐resistant nanofiltration membranes via reactive site‐bridged nanofibrous network

AbstractTraditional nanofiltration membranes often struggle to maintain stability in harsh environments due to issues like swelling, chemical bond dissociation, and polymer chain creep. Fluoropolymers like poly(ethylene‐chlorotrifluoroethylene) (ECTFE) are promising substrate candidates for broad‐spectrum corrosion‐resistant nanofiltration (CRNF) membranes, but their solvent insolubility and hydrophobicity present significant processing challenges. This study harnesses the electrospinnability and abundant reactive sites of polyvinyl alcohol to create a reactive site‐bridged nanofibrous network. This network provides reactive sites to decorate the hydrophobic ECTFE substrate and bridges the molecular selective layer through aldolization, Schiff base reactions, and esterification. The resulting robust thin‐film nanofibrous composite membranes exhibit high rejection rates for small molecular dyes under a variety of harsh conditions, including exposure to 10 wt% H2SO4, 1 M NaOH, ethanol, N,N‐dimethylformamide, N‐methylpyrrolidone, and 80°C solutions. This work paves the way for designing next‐generation broad‐spectrum CRNF membranes, enhancing their applicability in diverse harsh environments.

Ultrashort Peptide Hydrogels Biomaterials with Potent Antibacterial Activity.

For the past few decades, ultrashort peptide hydrogels have been at the forefront of biomaterials due to their unique properties like biocompatibility, tunable mechanical properties, and potent antibacterial activity. These ultrashort peptides self-assemble into a hydrogel matrix with nanofibrous networks. In this minireview, we have explored the design and self-assembly of these ultrashort peptide hydrogels by focusing on their antibacterial properties. Cationic and hydrophobic residues are incorporated to engineer the peptides, facilitating interaction with bacterial membranes and leading to membrane disruption and cell death. The hydrogels exhibit broad-spectrum antibacterial activity against both Gram-positive and Gram-negative bacteria. Overall, this minireview highlights the potential of ultrashort peptide hydrogels as versatile and practical antibacterial biomaterials, providing a novel approach to combating bacterial infections and addressing the growing challenge of antibiotic resistance.

Pulp regeneration using a peptide nanofiber artificial scaffold on animal models: A preliminary study.

In regenerative endodontic procedures (REPs), it is crucial to find effective materials. This study introduces glycosaminoglycan (GAG) mimetic peptide amphiphile (PA, GAG-PA) and K-PA nanofibers, synthesized to emulate sulfated GAGs, aiming to enhance tissue repair within damaged pulp - an area where standardized protocols are currently lacking. The objective of this study was to investigate the regenerative potential of GAG-PA nanofibers in REP. Heparan sulfate mimicking PAs was designed to develop a bioactive nanofibrous supramolecular system. The cavities on the mesial surfaces of the first upper molars of 8 rats (4 rats in the study group and 4 in the control group) were prepared, and the pulps were perforated. Then, the material was applied onto the dental pulp, and the cavities were closed with a self-curing glass ionomer cement filling material. Physiological saline was used in the control group. Thirty days after application, the teeth were extracted, and the formation of regenerative tissue sections in the pulp was evaluated using hematoxylin and eosin (H&E) staining and Masson's trichrome staining. After 30 days, H&E staining demonstrated robust tissue regeneration in the implanted region, with minimal neutrophil infiltration. Masson's trichrome staining confirmed reparative dentin formation. Quantitative analysis revealed a regeneration percentage of 85% in the study group, compared to 80% in the control group. Statistical analysis showed no significant difference in regeneration between the groups (p > 0.05). Our comprehensive study, utilizing GAG-PA and K-PA nanofibers, demonstrated successful synthesis, characterization and formation of nanofiber networks. The in vivo experiment with rats exhibited substantial tissue regeneration with quantifiable results supporting the efficacy of the nanofiber approach. Statistical analysis confirmed the consistency between the study and control groups, emphasizing the potential of these nanofibers in endodontic tissue regeneration applications.

Biomimetic three-dimensional scaffolds with aligned electrospun nanofibers and enlarged pores for enhanced cardiac cell colonization

Among the wide range of biomimetic scaffolds, those made of aligned nanofibers represent an important class for tissue engineering applications, and particularly for cardiac repair. Electrospinning is a powerful technique allowing the fabrication of scaffolds with aligned nanofibers. However, the resulting morphology is characterized by low porosity and small pore size due to the formation of a compact structure of aligned fibers preventing cell colonization inside the scaffold. In the present work, supported by numerical simulation, it is demonstrated that when optimal electrostatic interactions occur during the simultaneous deposition of electrospun nanofibers and electrosprayed microparticles on a collector rotating at high speed, a 3D structured scaffold is obtained. Thanks to a self-organization mechanism, islands of microparticles intercalate inside a network of loosely packed and highly aligned nanofibers. In the case of poly(lactic acid) electrospinning and poly(glycerol sebacate)/cyclodextrin electrospraying, the resulting 3D biomimetic scaffold, deeply investigated by X-ray microtomography and mechanical characterization, shows an open porosity with enlarged interconnected pores with a mechanical behavior mimicking that of cardiac tissue. Finally, after functionalizing the fiber surface using laminin, it is shown an efficient 3D colonization of cardiac cells through a network of aligned nanofibers.

Strong and tough bioplastics prepared by in-situ polymerization of ε-caprolactone-oligomers in lignocellulosic nanofiber network.

Cellulose biocomposites have emerged as attractive alternatives to fossil-based plastics because of their excellent renewability and biodegradability; however, their water resistance and mechanical properties remain challenging. Herein, a cellulose- containing bioplastic with high a reinforcement content, water stability, and toughness is reported. Lignin-containing cellulose nanofibers (LCNF) were prepared by pretreating eucalyptus wood powder with a deep eutectic solvent and high-pressure homogenization. Then, the pre-synthesized ε-caprolactone oligomers were in-situ polymerized in LCNF. The interaction of LCNF with ε-caprolactone-oligomers in the LCNF-crosslinked polycaprolactone (LCNF-PCL) bioplastic resulted in excellent mechanical properties (tensile strength: 76.59 MPa; toughness: 9.82 MJ m-3). The LCNF-PCL bioplastic also demonstrated excellent water stability (wet tensile strength: 34.21 MPa; water absorption: <5 %), thermal stability, and UV protection. This approach may provide a potential method for utilizing lignocellulosic resources to develop environmentally friendly bioplastics with good toughness and water stability.

Elucidating the efficacious capacitive deionization defluorination behaviors of heteroatom-doped hierarchical porous carbon nanofibers membrane

Heteroatom-doped porous carbons, particularly those incorporating nitrogen functionalities, demonstrate exceptional electrochemical properties advantageous for capacitive deionization (CDI) defluorination. Nevertheless, the underlying mechanism of fluoride removal remains inadequately understood, warranting comprehensive investigation to facilitate the practical implementation of CDI technology. Herein, a novel nitrogen-doped hierarchical porous carbon nanofiber membrane (HPCNM) derived from a hydrochloric acid etched FeNi3@CNFs (FeNi3 alloy encapsulated within carbon nanofibers) network was reasonably designed and synthesized for CDI defluorination. The HPCNM electrode exhibited superior defluorination capabilities, attributed to its distinctive hierarchical porosity and compositional architecture. The novel material achieves remarkable performance metrics, including a defluorination capacity of 58.38 mg g−1, rapid ion removal kinetics (0.97 mg g−1 min−1), and maintained efficiency throughout 20 operational cycles. Density functional theory (DFT) calculations indicate that nitrogen-doped carbon (NC) preferentially adsorbs fluoride, exhibiting the lowest adsorption energy. Fluoride interacts with NC through a combination of weak covalent bonds and van der Waals forces. Its inherent electronegativity, hardness, and high electrophilicity index, contrasted with low softness and nucleophilicity, facilitate the selective adsorption. Furthermore, an optimized NC electrode, operating at 1.2 V in simulated industrial wastewater, achieved fluoride removal compliant with national standards, demonstrating its practical applicability for treating contaminated effluent. These findings advance the understanding of selective fluoride removal, contributing to the development of targeted electrodes for industrial applications.

Development of a tumor organoid culture system with peptide-based hydrogels

Peptide-based hydrogel, the polymer materials with a special network structure, are widely used in various fields of biomedicine due to their stable properties and biocompatibility. Environment-responsive self-assembled peptide aqueous solutions can respond to environment changes by the self-assembly of peptides into nanofiber networks. Peptide-based hydrogels well simulate the extracellular matrix and cell growth microenvironment, being suitable for 3D cell culture and organoid culture. To establish a tumor organoid culture system with peptide-based hydrogels, we cultured Panc-1, U87, and H358 cells in a 3D spherical manner using CulX Ⅱ peptide-based hydrogels in 24-well plates for 15 days. The organoids showed a 3D spherical shape, and their sizes increased with the extension of the culture time, with a final diameter ranging from 150 to 300 μm. The organoids had a large number, varying sizes, good cell viability, clear edges, and a good shape, which indicated successful organoid construction. The tumor organoid culture system established in this study with CulX Ⅱ peptide-based hydrogels provides a model for studying tumor pathogenesis, drug development, and tumor suppression.

Enabling Separator Modification with Sulfiphilic CoTe2 Sites on Electrospun Carbon Nanofibers for High-Performance Lithium-Sulfur Batteries

Lithium-sulfur batteries (LSBs) have been recognized as a promising candidate for next generation electrochemical energy-storage technologies owing to their unparalleled theoretical capacity and energy density compared to conventional lithium-ion batteries. However, the sluggish redox kinetics of the electrochemistry and the formidable dissolution of polysulfides during cycling lead to poor sulfur utilization, serious polarization, cyclic instability, and hazardous Li corrosion/dendrites issues. Herein, cobalt tellurides and carbon nanofibers composites (CoTe2@CNFs) were designed, synthesized by facial electrospinning, and applied to modify the separator of Li–S batteries, providing a viable solution for these challenges. The composites feature polar CoTe2 nanoparticles embedded in each carbon nanofiber, and the carbon nanofibers intertwine with each other to form an interconnected 3D nanofiber network. The sulfiphilic CoTe2 nanoparticles exhibit dual functionality, as they both strongly interact with soluble polysulfides and dynamically facilitate polysulfide redox reactions. Moreover, the 3D nanofiber network not only provides an additional physical barrier to lithium polysulfides (LiPSs) but also enables uniform sulfur distribution, thereby significantly inhibiting LiPSs shuttling and accelerating sulfur conversion reactions. In summary, the functionally modified separator synergistically works as both redox mediators, catalyzing the sulfur conversion, and a buffer layer, regulating Li ions stripping/deposition behaviors. This work has provided a new avenue for designing nanomaterials with synergistic effect of catalytic conversion and chemisorption of polysulfides to promote high-performance Li-S batteries. Furthermore, it is expected to inspire the engineering of novel material architectures with enhanced properties for various energy-storage devices.

Frontispiece: Simultaneously Strengthening and Toughening All‐Natural Structural Materials via 3D Nanofiber Network Interfacial Design

Frontispiece: Simultaneously Strengthening and Toughening All‐Natural Structural Materials via 3D Nanofiber Network Interfacial Design