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Bio-applied molecularly imprinted polymers (MIPs) are biomimetic materials with tailor-made synthetic recognition sites, mimicking biological counterparts known for their sensitive and selective analyte detection. MIPs, specifically designed for biomarker analysis within biofluids, have the potential to significantly aid patient diagnostics at the point-of-care, enabling self-health monitoring and management. Recent research in this field, facilitated by the hybridisation of materials science and biology, has developed and utilised a variety of different polymerisation synthesis methods tailored to the bio-application of MIPs. This review evaluates the principles of molecular imprinting for disease diagnostics, including recent progress in integrated MIP-sensor technologies for high-affinity analyte detection in complex biofluids from serum and saliva to cerebrospinal fluid, sweat, urine, nasopharyngeal fluid, and tears. The work highlights the state-of-the-art in the progression of MIP-sensor technologies' translation into commercially available sensors and their potential contribution to disease detection systems in healthcare settings.

Conductive polymeric microneedle (MN) arrays as biointerface materials show promise for the minimally invasive monitoring of analytes in biodevices and wearables. There is increasing interest in microneedles as electrodes for biosensing, but efforts have been limited to metallic substrates, which lack biological stability and are associated with high manufacturing costs and laborious fabrication methods, which create translational barriers. In this work, additive manufacturing, which provides the user with design flexibility and upscale manufacturing, is employed to fabricate acrylic-based microneedle devices. These microneedle devices are used as platforms to produce intrinsically-conductive, polymer-based surfaces based on polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS). These entirely polymer-based solid microneedle arrays act as dry conductive electrodes while omitting the requirement of a metallic seed layer. Two distinct coating methods of 3D-printed solid microneedles, in situ polymerization and drop casting, enable conductive functionality. The microneedle arrays penetrate ex vivo porcine skin grafts without compromising conductivity or microneedle morphology and demonstrate coating durability over multiple penetration cycles. The non-cytotoxic nature of the conductive microneedles is evaluated using human fibroblast cells. The proposed fabrication strategy offers a compelling approach to manufacturing polymer-based conductive microneedle surfaces that can be further exploited as platforms for biosensing.

This technical note provides a step-by-step guide for the design and construction of a temperature-controlled nozzle-free electrospinning device. The equipment uses a rotating mandrel partially immersed within a polymer solution to produce fibers in an upward motion by inducing the formation of multiple Taylor cones and subsequently multi-jetting out of an electrified open surface. Free-surface electrospinning can overcome limitations and drawbacks associated with single and multi-nozzle spinneret configurations, such as low yield, limited production capacity, nonuniform electric field distribution, and clogging. Most importantly, this lab-scaled high-throughput device can provide an alternative economical route for needleless electrospinning research, in contrast to the high costs associated with industrially available upscaling equipment. Among the device's technical specifications, a key feature is a cryo-collector mandrel, capable of collecting fibers in sub-zero temperatures, which can induce ultra-porous nanostructures, wider pores, and subsequent in-depth penetration of cells. A multi-channel gas chamber allows the conditioning of the atmosphere, temperature, and airflow, while the chamber's design averts user exposure to the high-voltage components. All the Computer-Aided Design (CAD) files and point-by-point assembly instructions, along with a list of the materials used, are provided.

Lightweight, polyacrylonitrile‐derived electrodes with different additives were fabricated using high‐throughput nozzle‐free electrospinning. The electrospun precursor nanofibers (PNFs) containing iron oxide, gold nanoparticles, or reduced graphene oxide (rGO) were subjected to oxidative stabilization and carbonization to obtain a carbon‐rich conductive nanofiber structure. Scanning electron microscopy showed that the carbon nanofibers contracted between 11 and 55% while the Fourier‐transform infrared spectroscopy confirmed that the carbon nanofibers were thermally stable. Thermogravimetric and differential scanning calorimetry results revealed that the cross‐linking of the chain molecules and cyclization were completed. Next, cyclic voltammetry results indicated that the electroactivity of the modified screen‐printed carbon electrodes was decreased by 85% due to the presence of carbon glue. The modified device presented significant enhanced electrochemical responses with the inclusions of nanoparticles, with rGO showing a 2.13 times higher electroactive surface area, followed by iron oxide (two times) and gold nanoparticles (1.37 times) than the equivalent PNFs.

In this work, a nozzle-free electrospinning device was built to obtain high-throughput production of silk fibroin-based biocompatible composite fibers with tunable wettability. Synthetic biomaterials tend to present suboptimal cell growth and proliferation, with many studies linking this phenomenon to the hydrophobicity of such surfaces. In this study, electrospun mats consisting of Poly(caprolactone) blended with variant forms of Poly(glycerol sebacate) (PGS) and regenerated silk fibroin were fabricated. The main aim of this work was the development of fiber mats with tunable hydrophobicity/hydrophilicity properties depending on the esterification degree and concentration of PGS. A variation of the conventional protocol used for the extraction of silk fibroin from Bombyx mori cocoons was employed, achieving significantly increased yields of the protein, in a third of the time required via the conventional extraction protocol. By altering the surface properties of the electrospun membranes, the trinary composite biomaterial presented good in vitro fibroblast attachment behavior and optimal growth, indicating the potential of such constructs towards the development of an artificial skin-like platform that can aid wound healing and skin regeneration.

Additioanl file 1: Figure S1. Schematic representation of the co-axial electrospinning setup. Figure S2. Chemical structures of the proposed polymers and antimicrobial system. Figure S3. Fiber diameter distribution curves of the electrospun nanofibers. Figure S4. STEM micrographs of the core/shell NFs in different flow rates. Figure S5. FTIR-ATR spectra of (A) the raw and drug free fibers and (B) antimicrobial substance. Figure S6. FTIR-ATR region specific spectra of the drug containing nanofibrous mats. Figure S7. XPS survey of the electrospun nanofibrous mats. Figure S8. Absorbance spectra of 5CLO8Q and PHMB. Figure S9. Standard curves of PHMB and 5CLO8Q at pH 6.2 and 7.2. Table S1. XPS analysis of the C1s binding energies.

Fabrication of macroscopic three-dimensional (3D) structures made of nanofibers of widely used polymers is reported. 3D structures have several benefits over conventional flat two-dimensional (2D) structures by the added dimension. The structures have been fabricated by the 3D electrospinning technology that can build 3D structures rapidly due to certain additives in the solution and appropriate process conditions. The process parameters of 3D electrospinning have been identified and investigated to better understand the formation mechanism of the 3D build-up for polystyrene (PS), polyacrylonitrile (PAN), and polyvinylpyrrolidone (PVP). Different types of electrodes were inserted in the electrospinning chamber to alter the electric field and have better control over the shape of the 3D structure. The upscalability of this technology was investigated by using a standard electrospinner and a nozzle-free electrospinning setup. It was possible to manufacture 3D structures with these devices, highlighting the versatility of this technology. 3D electrospinning opens the pathway for the facile fabrication of macroscopic 3D structure with microfibrous features on a commercial scale.

Early diagnosis and efficient treatment are of paramount importance to fighting cancers. Monitoring the foreign body response of a patient to treatment therapies also plays an important role in improving the care that cancer patients receive by their medical practitioners. As such, there is extensive research being conducted into ultrasensitive point-of-care detection systems and "smart" personalized anticancer drug delivery systems. Electrospun nanofibers have emerged as promising materials for the construction of nanoscale biosensors and therapeutic platforms because of their large surface areas, controllable surface conformation, good surface modification, complex pore structure, and high biocompatibility. Electrospun nanofibers are produced by electrospinning, which is a very powerful and economically viable method of synthesizing versatile and scalable assemblies from a wide array of raw materials. This review describes the theory of electrospinning, achievements, and problems currently faced in producing effective biosensors/drug delivery systems, in particular, for cancer diagnosis and treatment. Finally, insights into future prospects are discussed.

A novel composite for skin tissue engineering applications by use of blends of Poly(vinylpyrrolidone) (PVP) and Poly (glycerol sebacate) (PGS) was fabricated via the scalable nozzle-free electrospinning technique. The formed PVP:PGS blends were morphologically, thermochemically and mechanically characterized. The morphology of the developed fibers correlated to the blend ratio. The tensile modulus appeared to be affected by the concentration of PGS within the blends, with an apparent decrease in the elastic modulus of the electrospun mats and an exponential increase of the elongation at break. Ultraviolet (UV) crosslinking of the composite fibers significantly decreased the construct's wettability and stabilized the formed fiber mats, which was indicated by contact angle measurements. In vitro examination showed good viability and proliferation of human dermal fibroblast cells. The present findings provide valuable insights for tuning the elastic properties of electrospun material by incorporating this unique elastomer as a promising future candidate for skin substitute constructs.

Scaffolds and implants used for tissue engineering need to be adapted for their mechanical properties with respect to their environment within the human body. Therefore, a novel composite for skin tissue engineering is presented by use of blends of Poly(vinylpyrrolidone) (PVP) and Poly(glycerol sebacate) (PGS) were fabricated via the needleless electrospinning technique. The formed PGS/PVP blends were morphologically, thermochemically and mechanically characterized. The morphology of the developed fibers related to the concentration of PGS, with high concentrations of PGS merging the fibers together plasticizing the scaffold. The tensile modulus appeared to be affected by the concentration of PGS within the blends, with an apparent decrease in the elastic modulus of the electrospun mats and an exponential increase of the elongation at break. Ultraviolet (UV) crosslinking of PGS/PVP significantly decreased and stabilized the wettability of the formed fiber mats, as indicated by contact angle measurements. In vitro examination showed good viability and proliferation of human dermal fibroblasts over the period of a week. The present findings provide important insights for tuning the elastic properties of electrospun material by incorporating this unique elastomer, as a promising future candidate for skin substitute constructs.

Glucose is a simple sugar that plays an essential role in many basic metabolic and signaling pathways. Many proteins have binding sites that are highly specific to glucose. The exponential increase of genomic data has revealed the identity of many proteins that seem to be central to biological processes, but whose exact functions are unknown. Many of these proteins seem to be associated with disease processes. Being able to predict glucose-specific binding sites in these proteins will greatly enhance our ability to annotate protein function and may significantly contribute to drug design. We hereby present the first glucose-binding site classifier algorithm. We consider the sugar-binding pocket as a spherical spatio-chemical environment and represent it as a vector of geometric and chemical features. We then perform Random Forests feature selection to identify key features and analyze them using support vector machines classification. Our work shows that glucose binding sites can be modeled effectively using a limited number of basic chemical and residue features. Using a leave-one-out cross-validation method, our classifier achieves a 8.11% error, a 89.66% sensitivity and a 93.33% specificity over our dataset. From a biochemical perspective, our results support the relevance of ordered water molecules and ions in determining glucose specificity. They also reveal the importance of carboxylate residues in glucose binding and the high concentration of negatively charged atoms in direct contact with the bound glucose molecule. Proteins 2009. © 2009 Wiley-Liss, Inc.

We present a new abstraction, association space, in the context of recursive subdivision surfaces. An association space relates elements in a recursive subdivision surface at a given refinement level to the elements of the surface at the previous refinement level. These associations allow a programmer to easily implement recursive subdivision algorithms and augment them with computations, such as multigrid techniques, that require inter-level traversals of the hierarchy of refined meshes. These associations also extend to distributed recursive subdivision surfaces. They underlie the mechanism for stitching the refined partitions of a mesh into a single refined mesh.

The complexity of modern products and design tools has made the exchange of design information more complex. It is widely recognised that the seamless capture, storage, and retrieval of design information is one of the major challenges for the next generation of computer aided design tools. This paper presents a model for the flow of design information that is sufficiently formal to eventually support a semantics-based approach for developing information exchange standards. The model classifies design information into various types, organises these types into information states and levels of abstraction, and identifies the various transformations that operate within and between the information states. The model’s ability to support a variety of design process models is illustrated by applying it to the Systems Integration of Manufacturing Applications (SIMA) design process model, and the model is then applied to a design example.