Time Controlled Protein Release from Layer‐by‐Layer Assembled Multilayer Functionalized Agarose Hydrogels

Axons of the adult central nervous system exhibit an extremely limited ability to regenerate after spinal cord injury. Experimentally generated patterns of axon growth are typically disorganized and randomly oriented. Support of linear axonal growth into spinal cord lesion sites has been demonstrated using arrays of uniaxial channels, templated with agarose hydrogel, and containing genetically engineered cells that secrete brain‐derived neurotrophic factor (BDNF). However, immobilizing neurotrophic factors secreting cells within a scaffold is relatively cumbersome, and alternative strategies are needed to provide sustained release of BDNF from templated agarose scaffolds. Existing methods of loading the drug or protein into hydrogels cannot provide sustained release from templated agarose hydrogels. Alternatively, here it is shown that pH‐responsive H‐bonded poly(ethylene glycol)(PEG)/poly(acrylic acid)(PAA)/protein hybrid layer‐by‐layer (LbL) thin films, when prepared over agarose, provided sustained release of protein under physiological conditions for more than four weeks. Lysozyme, a protein similar in size and isoelectric point to BDNF, is released from the multilayers on the agarose and is biologically active during the earlier time points, with decreasing activity at later time points. This is the first demonstration of month‐long sustained protein release from an agarose hydrogel, whereby the drug/protein is loaded separately from the agarose hydrogel fabrication process.     

Biomimetic Elastomeric Bioactive Siloxane‐Based Hybrid Nanofibrous Scaffolds with miRNA Activation: A Joint Physico‐Chemical‐Biological Strategy for Promoting Bone Regeneration

Rapid and efficient disease‐induced or critical‐size bone regeneration remains a challenge in tissue engineering due to the lack of highly bioactive biomaterial scaffolds. Physical structures such as nanostructures, chemical components such as silicon elements, and biological factors such as genes have shown positive effects on bone regeneration. Herein, a bioactive photoluminescent elastomeric silicate‐based nanofibrous scaffold with sustained miRNA release is reported for promoting bone regeneration based on a joint physico‐chemical‐biological strategy. Bioactive nanofibrous scaffolds are fabricated by cospinning poly (ε‐caprolactone) (PCL), elastomeric poly (citrates‐siloxane) (PCS), and bioactive osteogenic miRNA nanocomplexes (denoted PPM nanofibrous scaffolds). The PPM scaffolds possess uniform nanostructures, significantly enhanced tensile stress (≈15 MPa) and modulus (≈32 MPa), improved hydrophilicity (30–60°), controlled biodegradation, and strong blue fluorescence. Bioactive miRNA complexes are efficiently loaded into the nanofibrous matrix and exhibit long‐term release for up to 70 h. The PPM scaffolds significantly promote the adhesion, proliferation, and osteoblast differentiation of bone marrow stem cells in vitro and enhanced rat cranial defect restoration (12 weeks) in vivo. This work reports an attractive joint physico‐chemical‐biological strategy for the design of novel cell/protein‐free bioactive scaffolds for synergistic tissue regeneration.     

Programmed Shape‐Morphing Scaffolds Enabling Facile 3D Endothelialization

Rapid formation of a confluent endothelial monolayer is the key to the success of small‐diameter vascular grafts, which is significantly important for treating dangerous and even sometimes deadly vascular disorders. However, the difficulty to homogenously locate endothelial cells onto the lumen of small‐diameter tubular scaffolds makes 3D endothelialization greatly challenging. Here, novel shape‐morphing scaffolds enabling programmed deformation from planar shapes to small‐diameter tubular shapes are designed and developed by combining biocompatible shape memory polymer and electrospun nanofibrous membrane. Endothelial cells can be conveniently seeded and attached on the 2D surface of the scaffolds and subsequently self‐rolled into 3D organization at physiological temperature. Endothelial cell responses and functions are varied on the shape‐morphing scaffolds with different nanofibrous electrospun membranes as the inner layer, arisen from the inducement of scaffolds with different morphological, physical, and biochemical characteristics. Owing to excellent properties of the nanofibrous membrane fabricated by the coelectrospinning of poly‐ε‐caprolactone (PCL) and gelatin methacrylate (GelMA), the shape‐morphing scaffolds with a nanofibrous PCL/GelMA inner layer support desirable homogeneous endothelial cell attachment as well as the rapid formation of biomimetic cell–scaffold interaction and cell–cell interaction under the 3D cell culture condition, therefore offering a visible approach for facile 3D endothelialization.     

Electrodeposition on nanofibrous polymer scaffolds: Rapid mineralization, tunable calcium phosphate composition and topography

We developed a straightforward, fast, and versatile technique to fabricate mineralized nanofibrous polymer scaffolds for bone regeneration in this work. Nanofibrous poly(l-lactic acid) scaffolds were fabricated using both electrospinning and phase separation techniques. An electrodeposition process was designed to deposit calcium phosphate on the nanofibrous scaffolds. Such scaffolds contain a high quality mineral coating on the fiber surface with tunable surface topography and chemical composition by varying the processing parameters, which can mimic the composition and structure of natural bone extracellular matrix and provide a more biocompatible interface for bone regeneration.     

Bioinspired Hydrogel Electrospun Fibers for Spinal Cord Regeneration

Fully simulating the components and microstructures of soft tissue is a challenge for its functional regeneration. A new aligned hydrogel microfiber scaffold for spinal cord regeneration is constructed with photocrosslinked gelatin methacryloyl (GelMA) and electrospinning technology. The directional porous hydrogel fibrous scaffold consistent with nerve axons is vital to guide cell migration and axon extension. The GelMA hydrogel electrospun fibers soak up water more than six times their weight, with a lower Young's modulus, providing a favorable survival and metabolic environment for neuronal cells. GelMA fibers further demonstrate higher antinestin, anti‐Tuj‐1, antisynaptophysin, and anti‐CD31 gene expression in neural stem cells, neuronal cells, synapses, and vascular endothelial cells, respectively. In contrast, anti‐GFAP and anti‐CS56 labeled astrocytes and glial scars of GelMA fibers are shown to be present in a lesser extent compared with gelatin fibers. The soft bionic scaffold constructed with electrospun GelMA hydrogel fibers not only facilitates the migration of neural stem cells and induces their differentiation into neuronal cells, but also inhibits the glial scar formation and promotes angiogenesis. Moreover, the scaffold with a high degree of elasticity can resist deformation without the protection of a bony spinal canal. The bioinspired aligned hydrogel microfiber proves to be efficient and versatile in triggering functional regeneration of the spinal cord.     

Nanostructured Biomaterials for Regeneration

Biomaterials play a pivotal role in regenerative medicine, which aims to regenerate and replace lost/dysfunctional tissues or organs. Biomaterials (scaffolds) serve as temporary 3D substrates to guide neo tissue formation and organization. It is often beneficial for a scaffolding material to mimic the characteristics of extracellular matrix (ECM) at the nanometer scale and to induce certain natural developmental or/and wound healing processes for tissue regeneration applications. This article reviews the fabrication and modification technologies for nanofibrous, nanocomposite, and nanostructured drug‐delivering scaffolds. ECM‐mimicking nanostructured biomaterials have been shown to actively regulate cellular responses including attachment, proliferation, differentiation, and matrix deposition. Nanoscaled drug delivery systems can be successfully incorporated into a porous 3D scaffold to enhance the tissue regeneration capacity. In conclusion, nanostructured biomateials are a very exciting and rapidly expanding research area, and are providing new enabling technologies for regenerative medicine.     

Aligned PCL Fiber Conduits Immobilized with Nerve Growth Factor Gradients Enhance and Direct Sciatic Nerve Regeneration

Topographical guidance and chemotaxis are crucial factors for peripheral nerve regeneration. This study describes the preparation of highly aligned poly(ε‐caprolactone) (PCL) fiber conduits coated with a concentration gradient of nerve growth factor (NGF) (A/G‐PCL) using a newly designed electrospinning receiving device. The A/G‐PCL conduits are confirmed in vitro to enhance and attract the neurite longitudinal growth of dorsal root ganglion (DRG) neurons toward their high‐concentration gradient side. In vivo, the A/G‐PCL conduits are observed to direct a longitudinal stronger attraction of axons and migration of Schwann cells in 15 mm rat sciatic nerve defects. At 12 weeks, rats transplanted with A/G‐PCL conduits show satisfactory morphological and functional improvements in g‐ratio, total number, and area of myelinated nerve fibers as well as the sciatic function index, compound muscle action potentials, and muscle wet weight ratio as compared to aligned PCL fibers conduits with uniform NGF (A/U‐PCL). The performance of A/G‐PCL is similar to that of autografts. Moreover, mRNA‐seq and RT‐PCR results reveal that Rap1, MAPK, and cell adhesion molecules signaling pathways are closely associated with axon chemotactic response and attraction. Altogether, by combining structural guidance with axon chemotaxis, the NGF‐gradient/aligned PCL fiber conduits represent a promising approach for peripheral nerve defect repair.     

Conductive Core–Sheath Nanofibers and Their Potential Application in Neural Tissue Engineering

Conductive core–sheath nanofibers are prepared by a combination of electrospinning and aqueous polymerization. Specifically, nanofibers electrospun from poly(ε‐caprolactone) (PCL) and poly(L ‐lactide) (PLA) are employed as templates to generate uniform sheaths of polypyrrole (PPy) by in‐situ polymerization. These conductive core–sheath nanofibers offer a unique system to study the synergistic effect of different cues on neurite outgrowth in vitro. It is found that explanted dorsal root ganglia (DRG) adhere well to the conductive core–sheath nanofibers and generate neurites across the surface when there is a nerve growth factor in the medium. Furthermore, the neurites can be oriented along one direction and enhanced by 82% in terms of maximum length when uniaxially aligned conductive core–sheath nanofibers are compared with their random counterparts. Electrical stimulation, when applied through the mats of conductive core–sheath nanofibers, is found to further increase the maximum length of neurites for random and aligned samples by 83% and 47%, respectively, relative to the controls without electrical stimulation. Together these results suggest the potential use of the conductive core–sheath nanofibers as scaffolds in applications such as neural tissue engineering.     

Complementary Co‐assembling Peptides: From In Silico Studies to In Vivo Application

Self‐assembling biomaterials offer an unprecedented chance of successfully facing most of the challenges of various biomedical fields, and, in particular, of tissue engineering. Nonetheless co‐assembling peptides (CAPs), taking advantage of the theory and empirical findings developed for self‐assembling peptides, could provide an even better control over cell cultures, drug delivery, and transplantation therapies. This study follows a “full” bottom‐up approach to develop new CAPs for neural tissue engineering applications. After molecular aggregation analysis via coarse‐grained simulations, LKLK12, LDLD12, and the functionalized KLPGWSG‐LDLD12 CAPs are synthesized and characterized assessing their co‐assembled secondary structures, the biomechanical properties of the obtained hydrogels, and the morphological features of the assembled nanofibers. The biological influence on viability and differentiation of human and murine neural stem cells are tested in vitro and neuroregenerative potentials in complete spinal cord transections are verified in vivo. Upon mixing of CAPs, the spontaneous formation of double layers of β‐sheets with a high degree of integration of the two CAP species is demonstrated. The formation of entangled nanofibrous structures give rise to shear‐thinning hydrogels. The in vitro results are comparable to a standard state‐of‐the‐art cell culture substrate and nervous regeneration in vivo is enhanced.     

A Hierarchical Janus Nanofibrous Membrane Combining Direct Osteogenesis and Osteoimmunomodulatory Functions for Advanced Bone Regeneration

An ideal guided bone regeneration membrane (GBRM) is expected not only to perform barrier function, but also to enhance osteogenesis and resist bacteria infection. However, currently available membranes have limited bioactivities. To address this challenge, a Janus GBRM (JGM) is designed and fabricated by sequential fractional electrospinning here. The random gelatin fibers loaded with hydroxyapatite (HAP) are designed as the inner face to promote the osteoblasts’ adhesion, proliferation, and osteogenic differentiation, meanwhile the aligned poly(caprolactone) (PCL) nanofibers loaded with poly(methacryloxyethyltrimethyl ammonium chloride-co-2-Aminoethyl 2-methylacrylate hydrochloride) (P(DMC-AMA)) are designed as the outer layer to resist epithelia invasion and bacterial infection. In vitro assays reveal that the inner face displays enhanced osteogenic effects, meanwhile the outer surface can regulate the epithelia to spread along the aligned direction and kill the contacted bacteria. Interestingly, the outer face can induce macrophages to polarize toward the M2 phenotype, thus manipulating a favorable osteoimmune environment. These results suggest that the JGM simultaneously meets the critical requirements of barrier, osteogenic, antibacterial, and osteoimmunomodulatory functions. Consequently, the JGM shows better in vivo bone tissue regeneration performance than the commercial Bio-Gide membrane. This work provides a novel platform to design multi-functional membranes/scaffolds, displaying great potential applications in tissue engineering.     

Highly Aligned Nanofibrous Scaffold Derived from Decellularized Human Fibroblasts

Native tissues are endowed with a highly organized nanofibrous extracellular matrix (ECM) that directs cellular distribution and function. The objective of this study is to create a purely natural, uniform, and highly aligned nano­fibrous ECM scaffold for potential tissue engineering applications. Synthetic nanogratings (130 nm in depth) are used to direct the growth of human dermal fibroblasts for up to 8 weeks, resulting in a uniform 70 μm‐thick fibroblast cell sheet with highly aligned cells and ECM nanofibers. A natural ECM scaffold with uniformly aligned nanofibers of 78 ± 9 nm in diameter is generated after removing the cellular components from the fibroblast sheet. The elastic modulus of the scaffold is well maintained after the decellularization process because of the preservation of elastin fibers. Reseeding human mesenchymal stem cells (hMSCs) shows the excellent capacity of the scaffold in directing and supporting cell alignment and proliferation along the underlying fibers. The scaffold's biocompatibility is further examined by an in vitro inflammation assay with seeded macrophages. The aligned ECM scaffold induces a significantly lower immune response compared to its unaligned counterpart, as detected by the pro‐inflammatory cytokines secreted from macrophages. The aligned nanofibrous ECM scaffold holds great potential in engineering organized tissues.     

Polymer Scaffolds for Small‐Diameter Vascular Tissue Engineering

To better engineer small‐diameter blood vessels, a few types of novel scaffolds are fabricated from biodegradable poly(L ‐lactic acid) (PLLA) by means of thermally induced phase‐separation (TIPS) techniques. By utilizing the differences in thermal conductivities of the mold materials and using benzene as the solvent scaffolds with oriented gradient microtubular structures in the axial or radial direction can be created. The porosity, tubular size, and the orientational direction of the microtubules can be controlled by the polymer concentration, the TIPS temperature, and by utilizing materials of different thermal conductivities. These gradient microtubular structures facilitate cell seeding and mass transfer for cell growth and function. Nanofibrous scaffolds with an oriented and interconnected microtubular pore network are also developed by a one‐step TIPS method using a benzene/tetrahydrofuran mixture as the solvent without the need for porogen materials. The structural features of such scaffolds can be conveniently adjusted by varying the solvent ratio, phase‐separation temperature, and polymer concentration to mimic the nanofibrous features of an extracellular matrix. These scaffolds were fabricated for the tissue engineering of small‐diameter blood vessels by utilizing their advantageous structural features to facilitate blood‐vessel regeneration.     

Novel nanofibrous scaffolds for water filtration with bacteria and virus removal capability

We demonstrate a new class of composite fibrous membranes, consisting of an ultra-fine cellulose nanofibrous network infused into an electrospun polyacrylonitrile (PAN) nanofibrous scaffold on a melt-blown polyethylene terephthalate (PET) non-woven substrate for water purification. Depending on the infusion process and the ultra-fine cellulose nanofibers (UFCNs) used [e.g. modified ultra-fine cellulose nanofibers (m-UFCNs) or microcrystalline cellulose nanofibers (MCCNs)], different nanostructured scaffolds were formed as seen by electron microscopy. Membranes with UFCNs consist of an interwoven two-dimensional ultra-fine nanofibrous network that is deeply entangled with the electrospun scaffold and organized in a quasi-three-dimensional fashion, while those with MCCNs tend to locally wrap around the electrospun scaffolding nanofibers without forming a major network. Filtration tests illustrated that both membranes, while maintaining high permeation flux, exhibited excellent retention capabilities for simultaneous sieving for bacteria and adsorption for viruses.     

Fabrication of Nanofiber Microarchitectures Localized within Hydrogel Microparticles and Their Application to Protein Delivery and Cell Encapsulation

A simple method to generate well‐defined microscopic architectures composed of electrospun nanofibers is reported and their potential application to biomedical fields are described. The photopatterning of polyethylene glycol (PEG) hydrogel on electrospun polycarprolactone (PCL) nanofibers leads to the formation of two different microdomains in nanofibrous mats: a bare nanofiber region and a hydrogel‐entrapped nanofiber region. The selective dissolution of bare nanofibers with an organic solvent that cannot penetrate the PEG hydrogel enables the localization of PCL nanofibers within the hydrogel microstructures, thus generating microarchitectured nanofibers. The resultant microarchitectures are easily detached from the substrate by the water‐induced swelling of the PEG hydrogel. Microparticles are ultimately obtained, the size and shape of which can be easily controlled with proper photomask designs. In proof of concept experiments, bovine serum albumin(BSA)‐loaded PCL nanofibers that are entrapped within the hydrogel microparticles are prepared and the sustained release of BSA from micropatterned nanofibers is successfully demonstrated, indicating the potential application of the proposed microarchitectured nanofibers to drug delivery systems. For another possible application, the capability of the nanofiber‐incorporated hydrogel to encapsulate mammalian cells is investigated and the incorporation of nanofibers within the PEG hydrogel promoted cell adhesion and spreading when compared with bare PEG hydrogel is confirmed.     

Production and Potential of Bioactive Glass Nanofibers as a Next‐Generation Biomaterial

Over the past decades, bioactive glass has played a central role in the bone regeneration field, due to its excellent bioactivity, osteoconductivity, and even osteoinductivity. Herein, exploitation of bioactive glass as a one‐dimensional nanoscale fiber by employing an electrospinning process based on a sol–gel precursor is reported for the first time. Under controlled processing conditions, continuous nanofibers have been generated successfully with variable diameters. The excellent bioactivity of the nanofiber is confirmed in vitro within a simulated body fluid by the rapid induction of bonelike minerals onto the nanofiber surface. The bone‐marrow‐derived cells are observed to attach and proliferate actively on the nanofiber mesh, and differentiate into osteoblastic cells with excellent osteogenic potential. The bioactive nanofibers have been further exploited in various forms, such as bundled filament, nanofibrous membrane, 3D macroporous scaffold, and nanocomposite with biopolymer, suggesting their versatility and potential applications in bone‐tissue engineering. Based on this study, the bioactive nanofibrous matrix is regarded as a promising next‐generation biomaterial in the bone‐regeneration field.     

Nanofibrillar Decellularized Wharton's Jelly Matrix for Segmental Tracheal Repair

Wharton's jelly (WJ) is considered a potential scaffold in tissue‐engineered trachea for its similar composition and function to cartilage tissue. However, the feasibility of using WJ to construct engineered neocartilage tissue has not been reported, let alone tubular tracheal cartilage regeneration and segmental tracheal lesion repair. Here, electrospun nanofibrous membranes composed of three different decellularized WJ matrix (DWJM)/poly(ε‐caprolactone) (PCL) ratios (8:2, 5:5, and 2:8) are fabricated. The results demonstrate improved degradation speed, absorption, and cell adhesion capacity but weakened mechanical properties with increased DWJM content, but satisfactory homogeneous cartilage regeneration is only achieved in the DWJM/PCL (8:2) group after 12 weeks in vivo culture. Furthermore, homogeneous, 3D, tubular, trachea‐shaped cartilage is constructed with a controllable lumen diameter and wall thickness based on the 2D nanofibrous membrane using a modified sandwich model, in which the chondrocyte‐membrane construct is rolled around a silicon tube. Most importantly, by combining the above schemes with previously established vascularization and epithelialization techniques, chondrification, vascularization, and epithelialization are achieved simultaneously thus realizing long‐term (6 months) circumferential tracheal lesion repair in a rabbit model with a biological structure and function similar to that of native trachea, representing a promising approach for the clinical application of tracheal tissue engineering.     

Evaluation of the Biocompatibility of PLACL/Collagen Nanostructured Matrices with Cardiomyocytes as a Model for the Regeneration of Infarcted Myocardium

Pioneering research suggests various modes of cellular therapeutics and biomaterial strategies for myocardial tissue engineering. Despite several advantages, such as safety and improved function, the dynamic myocardial microenvironment prevents peripherally or locally administered therapeutic cells from homing and integrating of biomaterial constructs with the infarcted heart. The myocardial microenvironment is highly sensitive due to the nanoscale cues that it exerts to control bioactivities, such as cell migration, proliferation, differentiation, and angiogenesis. Nanoscale control of cardiac function has not been extensively analyzed in the field of myocardial tissue engineering. Inspired by microscopic analysis of the ventricular organization in native tissue, a scalable in‐vitro model of nanoscale poly(L ‐lactic acid)‐co ‐poly(? ‐caprolactone)/collagen biocomposite scaffold is fabricated, with nanofibers in the order of 594 ± 56 nm to mimic the native myocardial environment for freshly isolated cardiomyocytes from rabbit heart, and the specifically underlying extracellular matrix architecture: this is done to address the specificity of the underlying matrix in overcoming challenges faced by cellular therapeutics. Guided by nanoscale mechanical cues provided by the underlying random nanofibrous scaffold, the tissue constructs display anisotropic rearrangement of cells, characteristic of the native cardiac tissue. Surprisingly, cell morphology, growth, and expression of an interactive healthy cardiac cell population are exquisitely sensitive to differences in the composition of nanoscale scaffolds. It is shown that suitable cell–material interactions on the nanoscale can stipulate organization on the tissue level and yield novel insights into cell therapeutic science, while providing materials for tissue regeneration.     

Peripheral Nerve‐Derived Matrix Hydrogel Promotes Remyelination and Inhibits Synapse Formation

Regeneration of injured nerve tissues requires intricate interplay of complex processes like axon elongation, remyelination, and synaptic formation in a tissue‐specific manner. A decellularized nerve matrix‐gel (DNM‐G) and a decellularized spinal cord matrix‐gel (DSCM‐G) are prepared from porcine sciatic nerves and spinal cord tissue, respectively, to recapitulate the microenvironment cues unique to the native tissue functions. Using an in vitro dorsal root ganglion–Schwann cells coculture model and proteomics analysis, it is confirmed that DNM‐G promotes far stronger remyelination activity and reduces synapse formation of the regenerating axons in contrast to DSCM‐G, Matrigel, and collagen I, consistent with its tissue‐specific function. Bioinformatics analysis indicates that the lack of neurotrophic factors and presence of some axon inhibitory molecules may contribute to moderate axonal elongation activity, while laminin β2, Laminin γ1, collagens, and fibronectin in DNM‐G promote remyelination. These results confirm that DNM‐G is a promising matrix material for peripheral nerve repair. This study provides more insights into tissue‐specific extracellular matrix components correlating to biological functions supporting functional regeneration.     

Highly Flexible Organic Nanofiber Phototransistors Fabricated on a Textile Composite for Wearable Photosensors

Highly flexible organic nanofiber phototransistors are fabricated on a highly flexible poly(ethylene terephthalate) (PET) textile/poly(dimethylsiloxane) (PDMS) composite substrate. Organic nanofibers are obtained by electrospinning, using a mixture of poly(3,3^″′‐didodecylquarterthiophene) (PQT‐12) and poly(ethylene oxide) (PEO) as the semiconducting polymer and processing aid, respectively. PDMS is used as both a buffer layer for flattening the PET textile and a dielectric layer in the bottom‐gate bottom‐contact device configuration. PQT‐12:PEO nanofibers can be well‐aligned on the textile composite substrate by electrospinning onto a rotating drum collector. The nanofiber phototransistors fabricated on the PET/PDMS textile composite substrate show highly stable device performance (on‐current retention up to 82.3 (±6.7)%) under extreme bending conditions, with a bending radius down to 0.75 mm and repeated tests over 1000 cycles, while those prepared on film‐type PET and PDMS‐only substrates exhibit much poorer performances. The photoresponsive behaviors of PQT‐12:PEO nanofiber phototransistors have been investigated under light irradiation with different wavelengths. The maximum photoresponsivity, photocurrent/dark‐current ratio, and external quantum efficiency under blue light illumination were 930 mA W^?1, 2.76, and 246%, respectively. Furthermore, highly flexible 10 × 10 photosensor arrays have been fabricated which are able to detect incident photonic signals with high resolution. The flexible photosensors described herein have high potential for applications as wearable photosensors.     

Ice‐Templated Scaffolds with Microridged Pores Direct DRG Neurite Growth

Successful spinal cord repair is thought to be promoted with hierarchically structured scaffolds. These should combine aligned porosity with additional linear features on the micrometer scale to guide axons across multiple length scales. Such scaffolds are generated through the carefully controlled directional solidification of an aqueous biopolymer solution, followed by lyophilization. Under specific freezing conditions this yields a highly regular and aligned lamellar architecture. This architecture exhibits uniform ridges of controlled height and width on the lamellar surface. These ridges run parallel to the pore axis, serving as secondary guidance features. The ridges are capable of linearly aligning 62.4% of chick dorsal root ganglia neurites to within ±10° of the ridge direction. Notably, neurites sprouting perpendicular to the ridge are guided into alignment with these microridged features.