Progress in the field of electrospinning for tissue engineering applications

Translational Challenges in Drug Therapy and Delivery Systems for Treating Chronic Lower Extremity Wounds

Despite several promising preclinical studies performed over the past two decades, there remains a paucity of market-approved drugs to treat chronic lower extremity wounds in humans. This translational gap challenges our understanding of human chronic lower extremity wounds and the design of wound treatments. Current targeted drug treatments and delivery systems for lower extremity wounds rely heavily on preclinical animal models meant to mimic human chronic wounds. However, there are several key differences between animal preclinical wound models and the human chronic wound microenvironment, which can impact the design of targeted drug treatments and delivery systems. To explore these differences, this review delves into recent new drug technologies and delivery systems designed to address the chronic wound microenvironment. It also highlights preclinical models used to test drug treatments specific for the wound microenvironments of lower extremity diabetic, venous, ischemic, and burn wounds. We further discuss key differences between preclinical wound models and human chronic wounds that may impact successful translational drug treatment design.

Development and characterization of Polycaprolactone/chitosan-based scaffolds for tissue engineering of various organs: A review

Research in creating 3D structures mirroring the extracellular matrix (ECM) with accurate environmental cues holds paramount significance in biological applications.Biomaterials that replicate ECM properties-mechanical, physicochemical, and biological-emerge as pivotal tools in mimicking ECM behavior.Incorporating synthetic and natural biomaterials is widely used to produce scaffolds suitable for the intended organs.Polycaprolactone (PCL), a synthetic biomaterial, boasts commendable mechanical properties, albeit with relatively modest biological attributes due to its hydrophobic nature.Chitosan (CTS) exhibits strong biological traits but lacks mechanical resilience for complex tissue regeneration.Notably, both PCL and CTS have demonstrated their application in tissue engineering for diverse types of tissues.Their combination across varying PCL:CTS ratios has increased the likelihood of fabricating scaffolds to address defects in sturdy and pliable tissues.This comprehensive analysis aspires to accentuate their distinct attributes within tissue engineering across different organs.The central focus resides in the role of PCL:CTS-based scaffolds, elucidating their contribution to the evolution of advanced functional 3D frameworks tailored for tissue engineering across diverse organs.Moreover, this discourse delves into the considerations pertinent to each organ.

A Color-Detectable Vitamin C Controlled-Release System Fabricated Using Electrospinning

This study develops a vitamin C controlled-release system, trackable via color changes as a function of vitamin C release. The system is composed of coaxial microfibers prepared via coaxial electrospinning, with a core of poly(ethylene oxide) (PEO) incorporating vitamin C, and a shell composed of polycaprolactone (PCL) containing polydiacetylene (PDA) as the color-changing material. The shell thickness is controlled by adjusting the amount of PCL ejected during electrospinning, allowing regulation of the release rate of vitamin C. When vitamin C added to PEO penetrates the PCL layer, the color of PDA changes from blue to red, indicating a color change. The results of this study can be applied to devices that require immediate detection of vitamin C release levels.

Degradable biomedical elastomers: paving the future of tissue repair and regenerative medicine

Degradable biomedical elastomers (DBE), characterized by controlled biodegradability, excellent biocompatibility, tailored elasticity, and favorable network design and processability, have become indispensable in tissue repair. This review critically examines the recent advances of biodegradable elastomers for tissue repair, focusing mainly on degradation mechanisms and evaluation, synthesis and crosslinking methods, microstructure design, processing techniques, and tissue repair applications. The review explores the material composition and cross-linking methods of elastomers used in tissue repair, addressing chemistry-related challenges and structural design considerations. In addition, this review focuses on the processing methods of two- and three-dimensional structures of elastomers, and systematically discusses the contribution of processing methods such as solvent casting, electrostatic spinning, and three-/four-dimensional printing of DBE. Furthermore, we describe recent advances in tissue repair using DBE, and include advances achieved in regenerating different tissues, including nerves, tendons, muscle, cardiac, and bone, highlighting their efficacy and versatility. The review concludes by discussing the current challenges in material selection, biodegradation, bioactivation, and manufacturing in tissue repair, and suggests future research directions. This concise yet comprehensive analysis aims to provide valuable insights and technical guidance for advances in DBE for tissue engineering.

Advances of polyolefins from fiber to nanofiber: fabrication and recent applications

Polyolefins are a widely accepted commodity polymer made from olefinic monomer consisting of carbon and hydrogen. This thermoplastic polymeric material is formed through reactive double bonds of olefins by the addition polymerization technique and it possesses a diverse range of unique features for a large variety of applications. Among the various types, polyethylene and polypropylene are the prominent classes of polyolefins that can be crafted and manipulated into diversified products for numerous applications. Research on polyolefins has boomed tremendously in recent times owing to the abundance of raw materials, low cost, lightweight, high chemical resistance, diverse functionalities, and outstanding physical characteristics. Polyolefins have also evidenced their potentiality as a fiber in micro to nanoscale and emerged as a fascinating material for widespread high-performance use. This review aims to provide an elucidation of the breakthroughs in polyolefins, namely as fibers, filaments, and yarns, and their applications in many domains such as medicine, body armor, and load-bearing industries. Moreover, the development of electrospun polyolefin nanofibers employing cutting-edge techniques and their prospective utilization in filtration, biomedical engineering, protective textiles, and lithium-ion batteries has been illustrated meticulously. Besides, this review delineates the challenges associated with the formation of polyolefin nanofiber using different techniques and critically analyzes overcoming the difficulties in forming functional nanofibers for the innovative field of applications.

Effects of aligned PLGA/SrCSH composite scaffolds on in vitro growth and osteogenic differentiation of human mesenchymal stem cells

Strontium (Sr) has important functions in bone remodeling. Incorporating strontium-doped α-calcium sulfate hemihydrate (SrCSH) into poly(lactic-co-glycolic acid) (PLGA) fibrous scaffolds were expected to increase its bio-activity and provide a potential material for bone tissue engineering. In the present study, Sr-containing aligned PLGA/SrCSH fibrous scaffolds similar to the architecture of natural bone were prepared via wet spinning. CCK-8 assay revealed that Sr-containing scaffolds possessed better bioactivity and supported favorable cell growth effectively. The aligned PLGA/SrCSH fibers exerted a contact effect on cell attachment, inducing regular cell alignment and influencing a series of cell behaviors. Releasing of high concentration Sr from a-PLGA/SrCSH scaffolds could induce high expression levels of BMP-2, increase ALP activity and upregulate RUNX-2 expression, and further promote the expressions of COL-I and OCN and the maximum mineralization. This study demonstrated that Sr and ordered structure in a-PLGA/SrCSH fibrous scaffolds could synergistically enhance the osteogenic differentiation of umbilical cord mesenchymal stem cells (UCMSCs) by regulating cell arrangement and expressions of osteogenic genes.

Piezoelectric-based bioactive zinc oxide-cellulose acetate electrospun mats for efficient wound healing: an in vitro insight

Being a complex physiological process involving the removal of damaged tissue debris and creating a new microenvironment for host tissue regeneration, wound healing is still a major challenge for healthcare professionals. Disruption of this process can lead to tissue inflammation, pathogenic infections, and scar formation. Current wound healing treatments primarily focus on passive tissue healing, lacking active engagement in the healing process. In recent years, a new class of functional biomaterials based on piezoelectric properties has emerged, which can actively participate in the wound healing process by harnessing mechanical forces generated from body movement. Herein, we have fabricated a bioactive Cellulose Acetate (CA) electrospun nanofibrous mat incorporating zinc oxide (ZnO) and investigated its efficiency for accelerated wound healing. We have characterized the physicochemical properties of the fabricated nanofibrous mats using various assays, including SEM, FTIR, TGA, mechanical testing, degradation analysis, porosity measurement, hemolysis assay, and piezoelectric d33 coefficient measurement. Through our investigation, we discovered the tunned piezoelectric coefficient of fabricated specimens due to incorporating ZnO into the CA fibers. In vitro studies also confirmed enhanced cell adhesion, proliferation, and migration, indicating faster wound healing potential. Overall, our findings support the efficacy of piezoelectric-based ZnO-incorporated bioactive CA nanofibrous mats for efficient wound healing.

Facile In Situ Assembly of Nanofibers within Three-Dimensional Porous Matrices with Arbitrary Characteristics for Creating Biomimetic Architectures

It is challenging to recapitulate the natural extracellular matrix's hierarchical nano/microfibrous three-dimensional (3D) structure with multilevel pores, good mechanical and hydrophilic properties, and excellent bioactivity for designing and developing advanced biomimetic materials. This work reports a new facile strategy for the scalable manufacturing of such a 3D architecture. Natural polymers in an aqueous solution are interpenetrated into a 3D microfibrous matrix with arbitrary shapes and property characteristics to self-assemble in situ into a nanofibrous network. The collagen fiber-like hierarchical structure and interconnected multilevel pores are achieved by self-assembly of the formed nanofibers within the 3D matrix, triggered by a simple cross-linking treatment. The as-prepared alginate/polypropylene biomimetic matrices are bioactive and have a tunable mechanical property (compressive modulus from ∼17 to ∼24 kPa) and a tunable hydrophilicity (water contact angle from ∼94° to 63°). This facile and versatile strategy allows eco-friendly and scalable manufacturing of diverse biomimetic matrices or modification of any existing porous matrices using different polymers.

Guided Tissue and Bone Regeneration Membranes: A Review of Biomaterials and Techniques for Periodontal Treatments

This comprehensive review provides an in-depth analysis of the use of biomaterials in the processes of guided tissue and bone regeneration, and their indispensable role in dental therapeutic interventions. These interventions serve the critical function of restoring both structural integrity and functionality to the dentition that has been lost or damaged. The basis for this review is laid through the exploration of various relevant scientific databases such as Scopus, PubMed, Web of science and MEDLINE. From a meticulous selection, relevant literature was chosen. This review commences by examining the different types of membranes used in guided bone regeneration procedures and the spectrum of biomaterials employed in these operations. It then explores the manufacturing technologies for the scaffold, delving into their significant impact on tissue and bone regenerations. At the core of this review is the method of guided bone regeneration, which is a crucial technique for counteracting bone loss induced by tooth extraction or periodontal disease. The discussion advances by underscoring the latest innovations and strategies in the field of tissue regeneration. One key observation is the critical role that membranes play in guided reconstruction; they serve as a barrier, preventing the entry of non-ossifying cells, thereby promoting the successful growth and regeneration of bone and tissue. By reviewing the existing literature on biomaterials, membranes, and scaffold manufacturing technologies, this paper illustrates the vast potential for innovation and growth within the field of dental therapeutic interventions, particularly in guided tissue and bone regeneration.

Use of Poly Lactic-co-glycolic Acid Nano and Micro Particles in the Delivery of Drugs Modulating Different Phases of Inflammation

Chronic inflammation contributes to the pathogenesis of many diseases, including apparently unrelated conditions such as metabolic disorders, cardiovascular diseases, neurodegenerative diseases, osteoporosis, and tumors, but the use of conventional anti-inflammatory drugs to treat these diseases is generally not very effective given their adverse effects. In addition, some alternative anti-inflammatory medications, such as many natural compounds, have scarce solubility and stability, which are associated with low bioavailability. Therefore, encapsulation within nanoparticles (NPs) may represent an effective strategy to enhance the pharmacological properties of these bioactive molecules, and poly lactic-co-glycolic acid (PLGA) NPs have been widely used because of their high biocompatibility and biodegradability and possibility to finely tune erosion time, hydrophilic/hydrophobic nature, and mechanical properties by acting on the polymer's composition and preparation technique. Many studies have been focused on the use of PLGA-NPs to deliver immunosuppressive treatments for autoimmune and allergic diseases or to elicit protective immune responses, such as in vaccination and cancer immunotherapy. By contrast, this review is focused on the use of PLGA NPs in preclinical in vivo models of other diseases in which a key role is played by chronic inflammation or unbalance between the protective and reparative phases of inflammation, with a particular focus on intestinal bowel disease; cardiovascular, neurodegenerative, osteoarticular, and ocular diseases; and wound healing.

Integrated Manufacturing of Suspended and Aligned Nanofibrous Scaffold for Structural Maturation and Synchronous Contraction of HiPSC-Derived Cardiomyocytes

Electrospun nanofiber constructs represent a promising alternative for mimicking the natural extracellular matrix in vitro and have significant potential for cardiac patch applications. While the effect of fiber orientation on the morphological structure of cardiomyocytes has been investigated, fibers only provide contact guidance without accounting for substrate stiffness due to their deposition on rigid substrates (e.g., glass or polystyrene). This paper introduces an in situ fabrication method for suspended and well aligned nanofibrous scaffolds via roller electrospinning, providing an anisotropic microenvironment with reduced stiffness for cardiac tissue engineering. A fiber surface modification strategy, utilizing oxygen plasma treatment combined with sodium dodecyl sulfate solution, was proposed to maintain the hydrophilicity of polycaprolactone (PCL) fibers, promoting cellular adhesion. Human-induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (CMs), cultured on aligned fibers, exhibited an elongated morphology with extension along the fiber axis. In comparison to Petri dishes and suspended random fiber scaffolds, hiPSC-CMs on suspended aligned fiber scaffolds demonstrated enhanced sarcomere organization, spontaneous synchronous contraction, and gene expression indicative of maturation. This work demonstrates the suspended and aligned nano-fibrous scaffold provides a more realistic biomimetic environment for hiPSC-CMs, which promoted further research on the inducing effect of fiber scaffolds on hiPSC-CMs microstructure and gene-level expression.

Oxygen-Generating Biomaterials for Translational Bone Regenerative Engineering

Successful regeneration of critical-size defects remains one of the significant challenges in regenerative engineering. These large-scale bone defects are difficult to regenerate and are often reconstructed with matrices that do not provide adequate oxygen levels to stem cells involved in the regeneration process. Hypoxia-induced necrosis predominantly occurs in the center of large matrices since the host tissue's local vasculature fails to provide sufficient nutrients and oxygen. Indeed, utilizing oxygen-generating materials can overcome the central hypoxic region, induce tissue in-growth, and increase the quality of life for patients with extensive tissue damage. This article reviews recent advances in oxygen-generating biomaterials for translational bone regenerative engineering. We discussed different oxygen-releasing and delivery methods, fabrication methods for oxygen-releasing matrices, biology, oxygen's role in bone regeneration, and emerging new oxygen delivery methods that could potentially be used for bone regenerative engineering.

A Study on the Effect of Doping Metallic Nanoparticles on Fracture Properties of Polylactic Acid Nanofibres via Molecular Dynamics Simulation

All-atom molecular dynamics simulations are conducted to elucidate the fracture mechanism of polylactic acid nanofibres doped with metallic nanoparticles. Extensional deformation is applied on polymer nanofibres decorated with spherical silver nanoparticles on the surface layer. In the obtained stress-strain curve, the elastic, yield, strain softening and fracture regions are recognized, where mechanical parameters are evaluated by tracking the stress, strain energy and geometrical evolutions. The energy release rate during crack propagation, which is a crucial factor in fracture mechanics, is calculated. The results show that the presence of doping nanoparticles improves the fracture properties of the polymer nanofibre consistently with experimental observation. The nanoparticles bind together polymer chains on the surface layer, which hinders crack initiation and propagation. The effect of the distribution of nanoparticles is studied through different doping decorations. Additionally, a discussion on the variation of internal energy components during uniaxial tensile loading is provided to unravel the deformation mechanism of nanoparticle-doped nanofibres.

Biofunctionalization and Applications of Polymeric Nanofibers in Tissue Engineering and Regenerative Medicine

The limited ability of most human tissues to regenerate has necessitated the interventions namely autograft and allograft, both of which carry the limitations of its own. An alternative to such interventions could be the capability to regenerate the tissue in vivo.Regeneration of tissue using the innate capacity of the cells to regenerate is studied under the discipline of tissue engineering and regenerative medicine (TERM). Besides the cells and growth-controlling bioactives, scaffolds play the central role in TERM which is analogous to the role performed by extracellular matrix (ECM) in the vivo. Mimicking the structure of ECM at the nanoscale is one of the critical attributes demonstrated by nanofibers. This unique feature and its customizable structure to befit different types of tissues make nanofibers a competent candidate for tissue engineering. This review discusses broad range of natural and synthetic biodegradable polymers employed to construct nanofibers as well as biofunctionalization of polymers to improve cellular interaction and tissue integration. Amongst the diverse ways to fabricate nanofibers, electrospinning has been discussed in detail along with advances in this technique. Review also presents a discourse on application of nanofibers for a range of tissues, namely neural, vascular, cartilage, bone, dermal and cardiac.

Electrospun Nanofibrous Membranes: A Versatile Medium for Waterproof and Breathable Application

Waterproof and breathable membranes that prevent liquid water penetration, while allowing air and moisture transmission, have attracted significant attention for various applications. Electrospun nanofiber materials with adjustable pore structures, easily tunable wettability, and good pore connectivity, have shown significant potential for constructing waterproof and breathable membranes. Herein, a systematic overview of the recent progress in the design, fabrication, and application of waterproof and breathable nanofibrous membranes is provided. The various strategies for fabricating the membranes mainly including one-step electrospinning and post-treatment of nanofibers are given as a starting point for the discussion. The different design concepts and structural characteristics of each type of waterproof and breathable membrane are comprehensively analyzed. Then, some representative applications of the membranes are highlighted, involving personal protection, desalination, medical dressing, and electronics. Finally, the challenges and future perspectives associated with waterproof and breathable nanofibrous membranes are presented.

Developing Antibiofilm Fibrillar Scaffold with Intrinsic Capacity to Produce Silver Nanoparticles

The development of biomedical systems with antimicrobial and antibiofilm properties is a difficult medical task for preventing bacterial adhesion and growth on implanted devices. In this work, a fibrillar scaffold was produced by electrospinning a polymeric organic dispersion of polylactic acid (PLA) and poly(α,β-(N-(3,4-dihydroxyphenethyl)-L-aspartamide-co-α,β-N-(2-hydroxyethyl)-L-aspartamide) (PDAEA). The pendant catechol groups of PDAEA were used to reduce silver ions in situ and produce silver nanoparticles onto the surface of the electrospun fibers through a simple and reproducible procedure. The morphological and physicochemical characterization of the obtained scaffolds were studied and compared with virgin PLA electrospun sample. Antibiofilm properties against Pseudomonas aeruginosa, used as a biofilm-forming pathogen model, were also studied on planar and tubular scaffolds. These last were fabricated as a proof of concept to demonstrate the possibility to obtain antimicrobial devices with different shape and dimension potentially useful for different biomedical applications. The results suggest a promising approach for the development of antimicrobial and antibiofilm scaffolds.

Bacterial Cellulose Composites with Polysaccharides Filled with Nanosized Cerium Oxide: Characterization and Cytocompatibility Assessment

A new biocompatible nanocomposite film material for cell engineering and other biomedical applications has been prepared. It is based on the composition of natural polysaccharides filled with cerium oxide nanoparticles (CeONPs). The preparative procedure consists of successive impregnations of pressed bacterial cellulose (BC) with a sodium alginate (ALG) solution containing nanoparticles of citrate-stabilized cerium oxide and a chitosan (CS) solution. The presence of CeONPs in the polysaccharide composite matrix and the interaction of the nanoparticles with the polymer, confirmed by IR spectroscopy, change the network architecture of the composite. This leads to noticeable changes in a number of properties of the material in comparison with those of the matrix's polysaccharide composition, viz., an increase in mechanical stiffness, a decrease in the degree of planar orientation of BC macrochains, an increase in hydrophilicity, and the shift of the processes of thermo-oxidative destruction of the material to a low-temperature region. The latter effect is considered to be caused by the redox activity of cerium oxide (reversible transitions between the states Ce⁴⁺ and Ce³⁺) in thermally stimulated processes in the nanocomposite films. In the equilibrium swollen state, the material retains a mechanical strength at the level of ~2 MPa. The results of in vitro tests (cultivation of multipotent mesenchymal stem cells) have demonstrated the good biocompatibility of the BC-ALG(CeONP)-CS film as cell proliferation scaffolds.

Engineering Nanofiber Scaffolds with Biomimetic Cues for Differentiation of Skin-Derived Neural Crest-like Stem Cells to Schwann Cells

Our laboratory reported the derivation of neural crest stem cell (NCSC)-like cells from the interfollicular epidermis of the neonatal and adult epidermis. These keratinocyte (KC)-derived Neural Crest (NC)-like cells (KC-NC) could differentiate into functional neurons, Schwann cells (SC), melanocytes, and smooth muscle cells in vitro. Most notably, KC-NC migrated along stereotypical pathways and gave rise to multiple NC derivatives upon transplantation into chicken embryos, corroborating their NC phenotype. Here, we present an innovative design concept for developing anisotropically aligned scaffolds with chemically immobilized biological cues to promote differentiation of the KC-NC towards the SC. Specifically, we designed electrospun nanofibers and examined the effect of bioactive cues in guiding KC-NC differentiation into SC. KC-NC attached to nanofibers and adopted a spindle-like morphology, similar to the native extracellular matrix (ECM) microarchitecture of the peripheral nerves. Immobilization of biological cues, especially Neuregulin1 (NRG1) promoted the differentiation of KC-NC into the SC lineage. This study suggests that poly-ε-caprolactone (PCL) nanofibers decorated with topographical and cell-instructive cues may be a potential platform for enhancing KC-NC differentiation toward SC.

A Comprehensive Review of Biopolymer Fabrication in Additive Manufacturing Processing for 3D-Tissue-Engineering Scaffolds

The selection of a scaffold-fabrication method becomes challenging due to the variety in manufacturing methods, biomaterials and technical requirements. The design and development of tissue engineering scaffolds depend upon the porosity, which provides interconnected pores, suitable mechanical strength, and the internal scaffold architecture. The technology of the additive manufacturing (AM) method via photo-polymerization 3D printing is reported to have the capability to fabricate high resolution and finely controlled dimensions of a scaffold. This technology is also easy to operate, low cost and enables fast printing, compared to traditional methods and other additive manufacturing techniques. This article aims to review the potential of the photo-polymerization 3D-printing technique in the fabrication of tissue engineering scaffolds. This review paper also highlights the comprehensive comparative study between photo-polymerization 3D printing with other scaffold fabrication techniques. Various parameter settings that influence mechanical properties, biocompatibility and porosity behavior are also discussed in detail.

Stretchable skin hydrating PVB patches with controlled pores' size and shape for deliberate evening primrose oil spreading, transport and release

With the increasing number of skin problems such as atopic dermatitis and the number of affected people, scientists are looking for alternative treatments to standard ointment or cream applications. Electrospun membranes are known for their high porosity and surface to volume area, which leads to a great loading capacity and their applications as skin patches. Polymer fibers are widely used for biomedical applications such as drug delivery systems or regenerative medicine. Importantly, fibrous meshes are used as oil reservoirs due to their excellent absorption properties. In our study, nano- and microfibers of poly (vinyl butyral-co-vinyl alcohol-co-vinyl acetate) (PVB) were electrospun. The biocompatibility of PVB fibers was confirmed with the keratinocytes culture studies, including cells' proliferation and replication tests. To verify the usability and stretchability of electrospun membranes, they were tested in two forms as-spun and elongated after uniaxially stretched. We examine oil transport through the patches for as-spun fibers and compare it with the numerical simulation of oil flow in the 3D reconstruction of nano- and microfiber networks. Evening primrose oil spreading and water vapor transmission rate (WVTR) tests were performed too. Finally, for skin hydration tests, manufactured materials loaded with evening primrose oil were applied to the forearm of volunteers for 6 h, showing increased skin moisture after using patches. This study clearly demonstrates that pore size and shape, together with fiber diameter, influence oil transport in the electrospun patches allowing to understand the key driving process of electrospun PVB patches for skin hydration applications. The oil release improves skin moisture and can be designed regarding the needs, by manufacturing different fibers' sizes and arrangements. The fibrous based patches loaded with oils are easy to handle and could remain on the altered skin for a long time and deliver the oil, therefore they are an ideal material for overnight bandages for skin treatment.

Combinatorial wound healing therapy using adhesive nanofibrous membrane equipped with wearable LED patches for photobiomodulation

Wound healing is the dynamic tissue regeneration process replacing devitalized and missing tissue layers. With the development of photomedicine techniques in wound healing, safe and noninvasive photobiomodulation therapy is receiving attention. Effective wound management in photobiomodulation is challenged, however, by limited control of the geometrical mismatches on the injured skin surface. Here, adhesive hyaluronic acid-based gelatin nanofibrous membranes integrated with multiple light-emitting diode (LED) arrays are developed as a skin-attachable patch. The nanofibrous wound dressing is expected to mimic the three-dimensional structure of the extracellular matrix, and its adhesiveness allows tight coupling between the wound sites and the flexible LED patch. Experimental results demonstrate that our medical device accelerates the initial wound healing process by the synergetic effects of the wound dressing and LED irradiation. Our proposed technology promises progress for wound healing management and other biomedical applications.

Bioinspired bimodal micro-nanofibrous scaffolds promote the tenogenic differentiation of tendon stem/progenitor cells for achilles tendon regeneration

Poor tendon repair remains a clinical problem due to the difficulties in replicating the complex multiscale hierarchical structure of native tendons. In this work, a bioinspired fibrous scaffold with bimodal micro-nanofibers and a teno-inductive aligned topography was developed to replicate microscale collagen fibers and nanoscale collagen fibrils that compose native tendons. The results showed indicated that the combination of micro- and nanofibers enhanced the mechanical properties. Furthermore, their biological performance was assessed using tendon stem/progenitor cells (TSPCs). Micro-nanofibers induced a higher cell aspect ratio and enhanced the tenogenic differentiation of TSPCs compared to micro- and nanocontrols. Interestingly, it was observed that scaffold nanotopography and microstructures promoted tenogenesis via activating the TGF-β/Smad2/3-mediated signaling pathway. The in situ implantation study confirmed that micro-nanofibrous scaffolds promoted the structural and mechanical properties of the regenerated Achilles tendon. Overall, our study shows that the bimodal micro-nanofibrous scaffold developed here presents a promising potential to improve the outcomes of tendon tissue engineering.

Acrylonitrile and Pullulan Based Nanofiber Mats as Easily Accessible Scaffolds for 3D Skin Cell Models Containing Primary Cells

(1) Background: Three-dimensional (3D) collagen I-based skin models are commonly used in drug development and substance testing but have major drawbacks such as batch-to-batch variations and ethical concerns. Recently, synthetic nanofibrous scaffolds created by electrospinning have received increasing interest as potential alternatives due to their morphological similarities to native collagen fibrils in size and orientation. The overall objective of this proof-of-concept study was to demonstrate the suitability of two synthetic polymers in creating electrospun scaffolds for 3D skin cell models. (2) Methods: Electrospun nanofiber mats were produced with (i) poly(acrylonitrile-co-methyl acrylate) (P(AN-MA)) and (ii) a blend of pullulan (Pul), poly(vinyl alcohol) (PVA) and poly(acrylic acid) (PAA) (Pul/PVA/PAA) and characterized by scanning electron microscopy (SEM) and diffuse reflectance infrared Fourier transform (DRIFT) spectra. Primary skin fibroblasts and keratinocytes were seeded onto the nanofiber mats and analyzed for phenotypic characteristics (phalloidin staining), viability (Presto Blue HS assay), proliferation (Ki-67 staining), distribution (H/E staining), responsiveness to biological stimuli (qPCR), and formation of skin-like structures (H/E staining). (3) Results: P(AN-MA) mats were more loosely packed than the Pul/PVA/PAA mats, concomitant with larger fiber diameter (340 nm ± 120 nm vs. 250 nm ± 120 nm, p < 0.0001). After sterilization and exposure to cell culture media for 28 days, P(AN-MA) mats showed significant adsorption of fetal calf serum (FCS) from the media into the fibers (DRIFT spectra) and increased fiber diameter (590 nm ± 290 nm, p < 0.0001). Skin fibroblasts were viable over time on both nanofiber mats, but suitable cell infiltration only occurred in the P(AN-MA) nanofiber mats. On P(AN-MA) mats, fibroblasts showed their characteristic spindle-like shape, produced a dermis-like structure, and responded well to TGFβ stimulation, with a significant increase in the mRNA expression of PAI1, COL1A1, and αSMA (all p < 0.05). Primary keratinocytes seeded on top of the dermis equivalent proliferated and formed a stratified epidermis-like structure. (4) Conclusion: P(AN-MA) and Pul/PVA/PAA are both biocompatible materials suitable for nanofiber mat production. P(AN-MA) mats hold greater potential as future 3D skin models due to enhanced cell compatibility (i.e., adsorption of FCS proteins), cell infiltration (i.e., increased pore size due to swelling behavior), and cell phenotype preservation. Thus, our proof-of-concept study shows an easy and robust process of producing electrospun scaffolds for 3D skin cell models made of P(AN-MA) nanofibers without the need for bioactive molecule attachments.

Fibrous Scaffolds for Muscle Tissue Engineering Based on Touch-Spun Poly(Ester-Urethane) Elastomer

Development of fiber-spinning technologies and materials with proper mechanical properties is highly important for the manufacturing of aligned fibrous scaffolds mimicking structure of the muscle tissues. Here, the authors report touch spinning of a thermoplastic poly(1,4-butylene adipate)-based polyurethane elastomer, obtained via solvent-free polymerization. This polymer possesses a combination of important advantages such as 1) low elastic modulus in the range of a few MPa, 2) good recovery ratio and 3) resilience, 4) processability, 5) nontoxicity, 6) biocompatibility, and 7) biodegradability that makes it suitable for fabrication of structures mimicking extracellular matrix of muscle tissue. Touch spinning allows fast and precise deposition of highly aligned micro- and nano-fibers without use of high voltage. C2C12 myoblasts readily align along soft polymer fibers and demonstrate high viability as well as proliferation that make proposed combination of polymer and fabrication method highly suitable for engineering skeletal muscles.

Electrospun Nanofibers for Manipulating the Soft Tissue Regeneration

Soft tissue damage is a common clinical problem that affects the lives of a large number of patients all over the world. It is of great importance to develop functional...

Fabrication of Antheraea pernyi Silk Fibroin-Based Thermoresponsive Hydrogel Nanofibers for Colon Cancer Cell Culture

Antheraea pernyi silk fibroin (ASF)-based nanofibers have wide potential for biomaterial applications due to superior biocompatibility. It is not clear whether the ASF-based nanofibers scaffold can be used as an in vitro cancer cell culture platform. In the current study, we fabricated novel ASF-based thermoresponsive hydrogel nanofibers by aqueous electrospinning for colon cancer (LoVo) cells culture. ASF was reacted with allyl glycidyl ether (AGE) for the preparation of allyl silk fibroin (ASF-AGE), which provided the possibility of copolymerization with allyl monomer. The investigation of ASF-AGE structure by 1H NMR revealed that reactive allyl groups were successfully linked with ASF. ASF-based thermoresponsive hydrogel nanofibers (p (ASF-AGE-NIPAAm)) were successfully manufactured by aqueous electrospinning with the polymerization of ASF and N-isopropylacrylamide (NIPAAm). The p (ASF-AGE-NIPAAm) spinning solution showed good spinnability with the increase of polymerization time, and uniform nanofibers were formed at the polymerization time of 360 min. The obtained hydrogel nanofibers exhibited good thermoresponsive that the LCST was similar with PNIPAAm at about 32 °C, and good degradability in protease XIV PBS solution. In addition, the cytocompatibility of colon cancer (LoVo) cells cultured in hydrogel nanofibers was assessed. It was demonstrated that LoVo cells grown on hydrogel nanofibers showed improved cell adhesion, proliferation, and viability than those on hydrogel. The results suggest that the p (ASF-AGE-NIPAAm) hydrogel nanofibers have potential application in LoVo cells culture in vitro. This study demonstrates the feasibility of fabricating ASF-based nanofibers to culture LoVo cancer cells that can potentially be used as an in vitro cancer cell culture platform.

Directing Axonal Growth: A Review on the Fabrication of Fibrous Scaffolds That Promotes the Orientation of Axons

Tissues are commonly defined as groups of cells that have similar structure and uniformly perform a specialized function. A lesser-known fact is that the placement of these cells within these tissues plays an important role in executing its functions, especially for neuronal cells. Hence, the design of a functional neural scaffold has to mirror these cell organizations, which are brought about by the configuration of natural extracellular matrix (ECM) structural proteins. In this review, we will briefly discuss the various characteristics considered when making neural scaffolds. We will then focus on the cellular orientation and axonal alignment of neural cells within their ECM and elaborate on the mechanisms involved in this process. A better understanding of these mechanisms could shed more light onto the rationale of fabricating the scaffolds for this specific functionality. Finally, we will discuss the scaffolds used in neural tissue engineering (NTE) and the methods used to fabricate these well-defined constructs.

Biotechnological Applications of Polymeric Nanofiber Platforms Loaded with Diverse Bioactive Materials

This review article highlights the critical research and formative works relating to nanofiber composites loaded with bioactive materials for diverse applications, and discusses the recent research on the use of electrospun nanofiber incorporating bioactive compounds such as essential oils, herbal bioactive components, plant extracts, and metallic nanoparticles. Inevitably, with the common advantages of bioactive components and polymer nanofibers, electrospun nanofibers containing bioactive components have attracted intense interests for their applications in biomedicine and cancer treatment. Many studies have only concentrated on the production and performance of electrospun nanofiber loaded with bioactive components; in this regard, the features of different types of electrospun nanofiber incorporating a wide variety of bioactive compounds and their developing trends are summarized and assessed in the present article, as is the feasible use of nanofiber technology to produce products on an industrial scale in different applications.

Fabrication and Characterization of PCL/PLGA Coaxial and Bilayer Fibrous Scaffolds for Tissue Engineering

Electrospinning is an innovative new fibre technology that aims to design and fabricate membranes suitable for a wide range of tissue engineering (TE) applications including vascular grafts, which is the main objective of this research work. This study dealt with fabricating and characterising bilayer structures comprised of an electrospun sheet made of polycaprolactone (PCL, inner layer) and an outer layer made of poly lactic-co-glycolic acid (PLGA) and a coaxial porous scaffold with a micrometre fibre structure was successfully produced. The membranes' propriety for intended biomedical applications was assessed by evaluating their morphological structure/physical properties and structural integrity when they underwent the degradation process. A scanning electron microscope (SEM) was used to assess changes in the electrospun scaffolds' structural morphology such as in their fibre diameter, pore size (μm) and the porosity of the scaffold surface which was measured with Image J software. During the 12-week degradation process at room temperature, most of the scaffolds showed a similar trend in their degradation rate except the 60 min scaffolds. The coaxial scaffold had significantly less mass loss than the bilayer PCL/PLGA scaffold with 1.348% and 18.3%, respectively. The mechanical properties of the fibrous membranes were measured and the coaxial scaffolds showed greater tensile strength and elongation at break (%) compared to the bilayer scaffolds. According to the results obtained in this study, it can be concluded that a scaffold made with a coaxial needle is more suitable for tissue engineering applications due to the improved quality and functionality of the resulting polymeric membrane compared to the basic electrospinning process. However, whilst fabricating a vascular graft is the main aim of this research work, the biological data will not present in this paper.

Development and Advantages of Biodegradable PHA Polymers Based on Electrospun PHBV Fibers for Tissue Engineering and Other Biomedical Applications

Biodegradable polymeric biomaterials offer a significant advantage in disposable or fast-consuming products in medical applications. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is an example of a polyhydroxyalkanoate (PHA), i.e., one group of natural polyesters that are byproducts of reactions taking place in microorganisms in conditions with an excess carbon source. PHA polymers are a promising material for the production of everyday materials and biomedical applications. Due to the high number of monomers in the group, PHAs permit modifications enabling the production of copolymers of different compositions and with different proportions of individual monomers. In order to change and improve the properties of polymer fibers, PHAs are combined with either other natural and synthetic polymers or additives of inorganic phases. Importantly, electrospun PHBV fibers and mats showed an enormous potential in both the medical field (tissue engineering scaffolds, plasters, wound healing, drug delivery systems) and industrial applications (filter systems, food packaging). This Review summarizes the current state of the art in processing PHBV, especially by electrospinning, its degradation processes, and biocompatibility studies, starting from a general introduction to the PHA group of polymers.

Application of "Magnetic Anchors" to Align Collagen Fibres for Axonal Guidance

The use of neural scaffolds with a highly defined microarchitecture, fabricated with standard techniques such as electrospinning and microfluidic spinning, requires surgery for their application to the site of injury. To circumvent the risk associated with aciurgy, new strategies for treatment are sought. This has led to an increase in the quantity of research into injectable hydrogels in recent years. However, little research has been conducted into controlling the building blocks within these injectable hydrogels to produce similar scaffolds with a highly defined microarchitecture. “Magnetic particle string” and biomimetic amphiphile self-assembly are some of the methods currently available to achieve this purpose. Here, we developed a “magnetic anchor” method to improve the orientation of collagen fibres within injectable 3D scaffolds. This procedure uses GMNP (gold magnetic nanoparticle) “anchors” capped with CMPs (collagen mimetic peptides) that “chain” them to collagen fibres. Through the application of a magnetic field during the gelling process, these collagen fibres are aligned accordingly. It was shown in this study that the application of CMP functionalised GMNPs in a magnetic field significantly improves the alignment of the collagen fibres, which, in turn, improves the orientation of PC12 neurites. The growth of these neurite extensions, which were shown to be significantly longer, was also improved. The PC12 cells grown in collagen scaffolds fabricated using the “magnetic anchor” method shows comparable cellular viability to that of the untreated collagen scaffolds. This capability of remote control of the alignment of fibres within injectable collagen scaffolds opens up new strategic avenues in the research for treating debilitating neural tissue pathologies.

Preparation and characterization of sodium alginate-PVA polymeric scaffolds by electrospinning method for skin tissue engineering applications

Sodium alginate (SA) has proven its high potential in tissue engineering and regenerative medicine. One of the main weaknesses of this polysaccharide is its low spinnability. Nanofiber-based scaffolds are of interest to scientists for biomedical engineering. The main aim of this study was to improve the spinnability of SA in combination with polyvinyl alcohol (PVA). The main parameters in the electrospinning of the optimized SA:PVA ratio, including voltage, flow rate, and working space were also optimized. To achieve this, response surface methodology under central composite design was employed to design the experiments scientifically. The final nanofiber scaffolds were studied using scanning electron microscopy, Fourier transform infrared spectroscopy for degradability, swelling, tensile strength, porosity, nanofiber diameter, contact angle, and cytotoxicity. Based on the results, the best ratio for SA : PVA was 1 : 6.5 that was spinnable in various values for the process parameters. The fabricated scaffolds under these conditions revealed good physical, chemical, mechanical, and biological features. L929 cell lines revealed high viability during 48 h culture. The results revealed that uniform and homogeneous nanofibers with regular size distribution (166 nm) were obtained at 30 kV, 0.55 μL h^-1, and 12.50 cm. To sum up, the fabricated scaffolds with the optimized ratio under the reported conditions indicate at good biologically compatible candidates for skin tissue engineering.

Bioremediation of Copper-Ions by Polymer Encapsulated and Immobilized Micrococcus Luteus

Bioremediation of copper (Cu²⁺ ) with immobilized Micrococcus luteus in polymer matrices has been broadly studied for a wide range of applications including wastewater treatment. Herein, the bioremediation efficiency based on modified immobilization techniques and by the addition of Cu²⁺ is investigated. Porous composite nonwovens with living M. luteus (living polymer composites) are prepared by encapsulation of the bacterial cells in poly(vinyl alcohol) (PVA) microparticles (M. luteus/PVA microparticles) produced by spray drying method. The M. luteus/PVA microparticles are chemically cross-linked. The hydrogel microparticles with encapsulated M. luteus are embedded in a nonwoven of poly (lactic acid) (PLA) electrospun short fibers provided by wet-laid method. Two different models of composite nonwovens are reported, in which the place position of the hydrogel PVA microparticles with encapsulated M. luteus and PLA nonwoven can affect the bioremediation process.

Uniform and Anisotropic Solid Electrolyte Membrane Enables Superior Solid-State Li Metal Batteries

Rational structure design is a successful approach to develop high-performance composite solid electrolytes (CSEs) for solid-state Li metal batteries. Herein, a novel CSE membrane is proposed, that consists of interwoven garnet/polyethylene oxide-Li bis(trifluoromethylsulphonyl)imide (LLZO/PEO-LiTFSI) microfibers. This CSE exhibits high Li-ion conductivity and exceptional Li dendrite suppression capability, which can be attributed to the uniform LLZO dispersion in PEO-LiTFSI and the vertical/horizontal anisotropic Li-ion conduction in the CSE. The uniform LLZO particles can generate large interaction regions between LLZO and PEO-LiTFSI, which thus form continuous Li-ion transfer pathways, retard the interfacial side reactions and strengthen the deformation resistance. More importantly, the anisotropic Li-ion conduction, that is, Li-ion transfers much faster along the microfibers than across the microfibers, can effectively homogenize the electric field distribution in the CSE during cycling, which thus prevents the excessive concentration of Li-ion flux. Finally, solid-state Li||LiFePO₄ cells based on this CSE show excellent electrochemical performances. This work enriches the structure design strategy of high-performance CSEs and may be helpful for further pushing the solid-state Li metal batteries towards practical applications.

Encapsulation of Pharmaceutical and Nutraceutical Active Ingredients Using Electrospinning Processes

Electrospinning is an inexpensive and powerful method that employs a polymer solution and strong electric field to produce nanofibers. These can be applied in diverse biological and medical applications. Due to their large surface area, controllable surface functionalization and properties, and typically high biocompatibility electrospun nanofibers are recognized as promising materials for the manufacturing of drug delivery systems. Electrospinning offers the potential to formulate poorly soluble drugs as amorphous solid dispersions to improve solubility, bioavailability and targeting of drug release. It is also a successful strategy for the encapsulation of nutraceuticals. This review aims to briefly discuss the concept of electrospinning and recent progress in manufacturing electrospun drug delivery systems. It will further consider in detail the encapsulation of nutraceuticals, particularly probiotics.

Hepatic patch by stacking patient-specific liver progenitor cell sheets formed on multiscale electrospun fibers promotes regenerative therapy for liver injury

Recently, use of cell sheets with bio-applicable fabrication materials for transplantation has been an attractive approach for the treatment of patients with liver failure. However, renewable and scalable cell sources for engineered tissue patches remain limited. We previously reported a new type of proliferating bipotent human chemically derived hepatic progenitor cells (hCdHs) developed by small molecule-mediated reprogramming. Here, we developed a patient-specific hepatic cell sheet constructed from liver biopsy-derived hCdHs on a multiscale fibrous scaffold by combining electrospinning and three-dimensional printing. Analysis of biomaterial composition revealed that the high-density electrospun sheet was superior in increasing the functional properties of hCdHs. Furthermore, the hepatic patch assembled by multilayer stacking with alternate cell sheets of hCdHs and human umbilical vein endothelial cells (HUVECs) recapitulated a liver tissue-like structure, with histological and morphological shape and size similar to those of primary human hepatocytes, and exhibited a significant increase in hepatic functions such as albumin secretion and activity of cytochrome P450 during in vitro hepatic differentiation compared with that in hCdH cells cultured in a two-dimensional monolayer. Interestingly, in the hepatic patch, the induction of functional hepatocytes was associated with both the electrospun fibrous-facilitated oncostatin M signaling and selective activation of AKT signaling by HUVECs. Notably, upon transplantation into a mouse model of therapeutic liver repopulation, the hepatic patch effectively repopulated the damaged parenchyma and induced the restoration of liver function with healthy morphology in the lobe and an improved survival rate (>70%) in mice. Overall, these results suggested that liver biopsy-derived hCdHs can be an efficient alternative source for developing hepatic cell sheets and patches with potential clinical applications in tissue engineering to advance liver regeneration.

Biomedical Applications of Electrospun Graphene Oxide

Graphene oxide (GO) has broad potential in the biomedical sector. The oxygen-abundant nature of GO means the material is hydrophilic and readily dispersible in water. GO has also been known to improve cell proliferation, drug loading, and antimicrobial properties of composites. Electrospun composites likewise have great potential for biomedical applications because they are generally biocompatible and bioresorbable, possess low immune rejection risk, and can mimic the structure of the extracellular matrix. In the current review, GO-containing electrospun composites for tissue engineering applications are described in detail. In addition, electrospun GO-containing materials for their use in drug and gene delivery, wound healing, and biomaterials/medical devices have been examined. Good biocompatibility and anionic-exchange properties of GO make it an ideal candidate for drug and gene delivery systems. Drug/gene delivery applications for electrospun GO composites are described with a number of examples. Various systems using electrospun GO-containing therapeutics have been compared for their potential uses in cancer therapy. Micro- to nanosized electrospun fibers for wound healing applications and antimicrobial applications are explained in detail. Applications of various GO-containing electrospun composite materials for medical device applications are listed. It is concluded that the electrospun GO materials will find a broad range of biomedical applications such as cardiac patches, medical device coatings, sensors, and triboelectric nanogenerators for motion sensing and biosensing.

Antibacterial agent-releasing scaffolds in dental tissue engineering

It seems quite challenging in tissue engineering to synthesize a base material with a range of essential activities, including biocompatibility, nontoxicity, and antimicrobial activities. Various types of materials are synthesized to solve the problem. This study aimed to provide the latest relevant information for practitioners about antibacterial scaffolds in dental tissue engineering. The PubMed search engine was used to review the relevant studies with a combination of the following terms as search queries: tissue engineering, scaffolds, antimicrobial, dentistry, dental stem cells, and oral diseases. It is noteworthy to state that only the terms related to tissue engineering in dentistry were considered. The antimicrobial scaffolds support the local tissue regeneration and prevent adverse inflammatory reactions; however, not all scaffolds have such positive characteristics. To resolve this potential defect, different antimicrobial agents are used during the synthesis process. Innovative methods in guided tissue engineering are actively working towards new ways to control oral and periodontal diseases.

Preparation of multilayer electrospun nanofibrous scaffolds containing soluble eggshell membrane as potential dermal substitute

Electrospinning of natural and synthetic polymers has shown to be a great candidate for the fabrication of tissue engineering scaffolds due to their similarity to the nanofibrous structure of natural extracellular matrix (ECM). Moreover, the addition of ECM-like proteins could enhance the biocompatibility of these scaffolds. In this study, soluble eggshell protein (SEP) was first extracted and synthesized from the raw eggshell membrane. The characteristics and biocompatibility of the extracted SEP were evaluated using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) analysis and 3-(4,5- dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide) (MTT) assay. For scaffolds fabrication, a three-layer nanofibrous composite structure was produced using the electrospinning technique. The outer layers composed of polyvinyl alcohol, chitosan, and extracted SEP while the middle layer composed of polyethylene oxide, gelatin, and zinc oxide nanoparticles (ZnO-NPs). For each layer, the electrospinning parameters were adjusted to form bead-free fibers. To improve fibers' stability against body fluids, the produced fibers were crosslinked using glutaraldehyde vapor. Several techniques such as scanning electron microscopy (SEM), energy dispersive X-ray, ATR-FTIR, swelling, tensile test, in vitro biodegradation, and MTT assay were implemented to evaluate the physical, chemical, and biological characterization of the fabricated fibers. The results showed that crosslinked fibers have adequate stability in water, suitable mechanical properties, and promising water uptake capacity. The MTT results also revealed that SEP and ZnO-NPs could increase scaffolds biocompatibility. Moreover, SEM photographs of cultured fibroblasts cells on the scaffolds showed that cells were well attached on the scaffolds and preserve their natural spindle shapes. Altogether, our findings demonstrated that the produced three-layer composite scaffolds are potential candidates for skin tissue engineering.

Graphene-Based Scaffolds for Regenerative Medicine

Leading-edge regenerative medicine can take advantage of improved knowledge of key roles played, both in stem cell fate determination and in cell growth/differentiation, by mechano-transduction and other physicochemical stimuli from the tissue environment. This prompted advanced nanomaterials research to provide tissue engineers with next-generation scaffolds consisting of smart nanocomposites and/or hydrogels with nanofillers, where balanced combinations of specific matrices and nanomaterials can mediate and finely tune such stimuli and cues. In this review, we focus on graphene-based nanomaterials as, in addition to modulating nanotopography, elastic modulus and viscoelastic features of the scaffold, they can also regulate its conductivity. This feature is crucial to the determination and differentiation of some cell lineages and is of special interest to neural regenerative medicine. Hereafter we depict relevant properties of such nanofillers, illustrate how problems related to their eventual cytotoxicity are solved via enhanced synthesis, purification and derivatization protocols, and finally provide examples of successful applications in regenerative medicine on a number of tissues.

Current Advances in 3D Tissue and Organ Reconstruction

Bi-dimensional culture systems have represented the most used method to study cell biology outside the body for over a century. Although they convey useful information, such systems may lose tissue-specific architecture, biomechanical effectors, and biochemical cues deriving from the native extracellular matrix, with significant alterations in several cellular functions and processes. Notably, the introduction of three-dimensional (3D) platforms that are able to re-create in vitro the structures of the native tissue, have overcome some of these issues, since they better mimic the in vivo milieu and reduce the gap between the cell culture ambient and the tissue environment. 3D culture systems are currently used in a broad range of studies, from cancer and stem cell biology, to drug testing and discovery. Here, we describe the mechanisms used by cells to perceive and respond to biomechanical cues and the main signaling pathways involved. We provide an overall perspective of the most recent 3D technologies. Given the breadth of the subject, we concentrate on the use of hydrogels, bioreactors, 3D printing and bioprinting, nanofiber-based scaffolds, and preparation of a decellularized bio-matrix. In addition, we report the possibility to combine the use of 3D cultures with functionalized nanoparticles to obtain highly predictive in vitro models for use in the nanomedicine field.