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Electroactive hydrogels based on derivatives of polyethyleneglycol (PEG), chitosan and polypyrrole were prepared via a combination of photopolymerization and oxidative chemical polymerization, and optionally doped with anions (e.g., lignin, drugs, etc.). The products were analyzed with a variety of techniques, including: FT-IR, UV-Vis, 1H NMR (solution state), 13C NMR (solid state), XRD, TGA, SEM, swelling ratios and rheology. The conductive gels swell ca. 8 times less than the non-conductive gels due to the presence of the interpenetrating network (IPN) of polypyrrole and lignin. A rheological study showed that the non-conductive gels are soft (G′ 0.35 kPa, G″ 0.02 kPa) with properties analogous to brain tissue, whereas the conductive gels are significantly stronger (G′ 30 kPa, G″ 19 kPa) analogous to breast tissue due to the presence of the IPN of polypyrrole and lignin. The potential of these biomaterials to be used for biomedical applications was validated in vitro by cell culture studies (assessing adhesion and proliferation of fibroblasts) and drug delivery studies (electrochemically loading the FDA-approved chemotherapeutic pemetrexed and measuring passive and stimulated release); indeed, the application of electrical stimulus enhanced the release of PEM from gels by ca. 10–15% relative to the passive release control experiment for each application of electrical stimulation over a short period analogous to the duration of stimulation applied for electrochemotherapy. It is foreseeable that such materials could be integrated in electrochemotherapeutic medical devices, e.g., electrode arrays or plates currently used in the clinic.

Drug delivery devices ensure the effective delivery of a broad range of therapeutics to millions of patients worldwide on a daily basis.1 Microneedles are a class of drug delivery device that provide pain free transdermal delivery with improved patient compliance.2-4 The release of metformin, a drug used in the treatment of cancer and diabetes, from polymer hydrogel-based microneedle patches was demonstrated in vitro. Tuning the composition of the polymer hydrogels enabled preparation of robust microneedle patches with mechanical properties such that they would penetrate skin (insertion force of a single microneedle to be ca. 40 N). Swelling experiments conducted at 20°C, 35°C and 60°C show temperature dependent degrees of swelling and kinetics (Fickian diffusion). Drug release from the hydrogel-based microneedles was fitted to various models (e.g., zero order, first order, second order, Korsmeyer-Peppas, Peppas-Sahlins), observing the best fit for the zero-order model. Such microneedles have potential application for transdermal delivery of metformin for the treatment of cancer and diabetes.

The development of stimuli‐responsive drug delivery systems offers significant opportunities for innovations in industry. It is possible to produce polymer‐based drug delivery devices enabling spatiotemporal control of the release of the drug triggered by an electrical stimulus. Here we describe the development of a wireless controller for drug delivery from conductive/electroactive polymer‐based biomaterials and demonstrate its function in vitro . The wireless polymer conduction controller device uses very low power, operating at 2.4 GHz, and has a supply voltage controller circuit which controls electrical stimulation voltage levels. The computer graphical user interface program communicates with the controller device, and it receives device information, device status and temperature data from the controller device. The prototype of the wireless controller system can trigger the delivery of a drug, dexamethasone phosphate, from a matrix of degradable electroactive polymers. Furthermore, we introduce the application of in silico toxicity screening as a potentially useful method to facilitate the design of non‐toxic degradable electroactive polymers for a multitude of biotechnological applications, addressing one of the key commercial challenges to biomaterial development, in accordance with ‘safe by design’ principles.

For some professionally, vocationally, or technically oriented careers, curricula delivered in higher education establishments may focus on teaching material related to a single discipline. By contrast, multidisciplinary, interdisciplinary, and transdisciplinary teaching (MITT) results in improved affective and cognitive learning and critical thinking, offering learners/students the opportunity to obtain a broad general knowledge base. Chemistry is a discipline that sits at the interface of science, technology, engineering, mathematics, and medicine (STEMM) subjects (and those aligned with or informed by STEMM subjects). This article discusses the significant potential of inclusion of chemistry in MITT activities in higher education and the real-world importance in personal, organizational, national, and global contexts. It outlines the development and implementation challenges attributed to legacy higher education infrastructures (that call for creative visionary leadership with strong and supportive management and administrative functions), and curriculum design that ensures inclusivity and collaboration and is pitched and balanced appropriately. It concludes with future possibilities, notably highlighting that chemistry, as a discipline, underpins industries that have multibillion dollar turnovers and employ millions of people across the world.

The CRISPR-Cas9 system has facilitated the genetic modification of various model organisms and cell lines. The outcomes of any CRISPR-Cas9 assay should be investigated to ensure/improve the precision of genome engineering. In this study, carbon nanotube-modified disposable pencil graphite electrodes (CNT/PGEs) were used to develop a label-free electrochemical nanogenosensor for the detection of point mutations generated in the genome by using the CRISPR-Cas9 system. Carbodiimide chemistry was used to immobilize the 5′-aminohexyl-linked inosine-substituted probe on the surface of the sensor. After hybridization between the target sequence and probe at the sensor surface, guanine oxidation signals were monitored using differential pulse voltammetry (DPV). Optimization of the sensitivity of the nanogenoassay resulted in a lower detection limit of 213.7 nM. The nanogenosensor was highly specific for the detection of the precisely edited DNA sequence. This method allows for a rapid and easy investigation of the products of CRISPR-based gene editing and can be further developed to an array system for multiplex detection of different-gene editing outcomes.

In situ forming hydrogels are a class of biomaterials that can fulfil a variety of important biomedically relevant functions and hold promise for the emerging field of patient-specific treatments (e.g., cell therapy, drug delivery). Here we report the results of our investigations on the generation of in situ forming hydrogels with potential for wound healing applications (e.g., complex blast injuries). The combination of polysaccharides that were oxidized to display aldehydes, amine displaying chitosan and nanostructured ZnO yields in situ forming bionanocomposite hydrogels. The physicochemical properties of the components, their cytotoxicity towards HaCat cells and the in vitro release of zinc ions on synthetic skin were studied. The in situ gel formation process was complete within minutes, the components were non-toxic towards HaCat cells at functional levels, Zn2+ was released from the gels, and such materials may facilitate wound healing.

Light-responsive polymers have a variety of potential biomedical applications. Here we describe the development of light-responsive polymer-based drug delivery systems in which a photo-responsive unit is incorporated in the polymers facilitating structural changes in the polymers upon exposure to light of various wavelengths. The photoactive unit can either be incorporated in the backbone or pendant on the backbone, and the chemistry of the photoactive unit determines if the polymers change conformation/shape, degrade, etc. (and therefore the mechanism of drug delivery), and the wavelength of light to which the polymers respond. We report the synthesis and characterization of light-responsive polymers and their processing into various materials morphologies that enable the delivery of drugs with wide ranging molecular weights in vitro.

The delivery of drugs in a controllable fashion is a topic of intense research activity in both academia and industry because of its impact in healthcare. Implantable electronic interfaces for the body have great potential for positive economic, health, and societal impacts; however, the implantation of such interfaces results in inflammatory responses due to a mechanical mismatch between the inorganic substrate and soft tissue, and also results in the potential for microbial infection during complex surgical procedures. Here, we report the use of conducting polypyrrole (PPY)-based coatings loaded with clinically relevant drugs (either an anti-inflammatory, dexamethasone phosphate (DMP), or an antibiotic, meropenem (MER)). The films were characterized and were shown to enhance the delivery of the drugs upon the application of an electrochemical stimulus in vitro, by circa (ca.) 10–30% relative to the passive release from non-stimulated samples. Interestingly, the loading and release of the drugs was correlated with the physical descriptors of the drugs. In the long term, such materials have the potential for application to the surfaces of medical devices to diminish adverse reactions to their implantation in vivo.

Organic electronic materials based on carbon nanotubes, graphene and conducting polymers have interesting optical and electronic properties and have attracted interest for a variety of applications in the technical and medical industries (e.g. batteries, bioactuators, biosensors, electronics, tissue engineering). Examples of conducting polymers include: polyacetylene, polyaniline, polythiophene, polyisothionaphthene, polyparavinylene, polyparaphenylene, polyparaphenylene sulfide, and polypyrrole. Polypyrrole is an interesting candidate polymer because of its biocompatibility and stability under atmospheric conditions, however, one of its drawbacks include poor mechanical properties and processability. With a view to enhancing the mechanical properties of polypyrrole films we have electrochemically produced a series of films including different amounts of biopolymers, and studied them with a variety of techniques (microscopy, spectroscopy etc.).

Bioelectronics: Introduction Electrical fields affect a variety of tissues (e.g. bone, cardiac, muscle, nerve and skin) and play important roles in a multitude of biological processes (e.g. angiogenesis, cell division, cell signalling, nerve sprouting, prenatal development and wound healing), which has inspired the development of electroactive biomaterials, some of which (e.g. non-biodegradable cardiac pacemakers, cochlear implants, electrodes for deep brain stimulation) have been clinically translated. Bioelectronics: Conductive/Electroactive Polymers The tuneable properties of conductive/electroactive polymers (CPs or EAPs, respectively) such as derivatives of polyaniline, polypyrrole or polythiophene (e.g. PEDOT) make them attractive components of electroactive biomaterials for drug delivery devices, electrodes or tissue scaffolds. The highly conjugated backbone of EAPs is responsible for their high conductivity, yet it also renders them non-biodegradable. Clearly, non-biodegradable EAPs are best suited for devices that will be implanted for long periods such as electrode-based biointerfaces, whereas, biodegradable EAPs are ideal for devices implanted for comparatively short durations such as drug delivery devices or tissue scaffolds. Electropolymerisation: problems and progress Electropolymerised films of polyaniline, polypyrrole or polythiophene (e.g. PEDOT) tend to have poor mechanical properties (particularly evident brittleness and cracking). We are developing simple scalable methods of preparing robust EAP-based materials. Examples presented here include negatively charged polysaccharides as dopants for positively charged polypyrrole. Characterisation We have begun to characterize the electrical, mechanical and biological properties of the films to identify problems and assess their prospects for biomedical applications in collaboration with physicists and biologists. Conclusion With a view towards the generation of robust electroactive biomaterials we have