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Medical soft robotics constitutes a rapidly developing field in the treatment of cardiovascular diseases, with a promising future for millions of patients suffering from heart failure worldwide. Herein, we review the present state and future direction of artificial muscle based soft robotic biomedical devices in supporting the inotropic function of the heart, focusing on the emerging electrothermally artificial heart muscles. Artificial muscle powered soft robotic devices can mimic the action of complex biological systems such as heart compression and twisting. These artificial muscles possess the ability to undergo complex deformations, aiding cardiac function while maintaining a limited weight and use of space. Two very promising candidates for artificial muscles are electrothermally actuated artificial heart muscles and biohybrid actuators using living cells or tissue embedded with artificial structures. Electrothermally actuated artificial heart muscles have demonstrated superior force generation while creating the prospect for fully soft robotic actuated ventricular assist devices. This review will critically analyse the limitations of currently available devices and discuss opportunities and directions for future research. Lastly, we will review and compare the properties of the cardiac muscle with those of different materials suitable for mechanical cardiac compression. This article is protected by copyright. All rights reserved.

Multi‐therapy strategies that coexist in a single system for cancer therapy has a great clinical application potential. In this paper, with the aim of establishing a suitable implantable platform for multimodal chemo‐photothermal cancer therapy, we have fabricated a coaxial composite hydrogel fiber that facilitated prolonged release of Doxorubicin from core. Fibers also served as NIR‐absorbing mediators, via incorporation of Cu2‐xSe nanoparticles in the shell, to facilitate chemo‐photothermal combinational effects. In vitro experiments exhibited excellent photo‐thermal properties of the fibers and exceptional cancer cell‐killing efficiency. Remarkably, in vivo antitumor experiments showed that Doxorubicin‐loaded coaxial hydrogel fibers containing Cu2‐xSe nanoparticles had outstanding antitumor efficacy, compared with chemotherapy or photothermal application alone. Overall, the coaxial composite hydrogel fibers provided a safe and efficacious implantable platform for multimodal chemo‐photothermal therapy that could potentially be used to control the progression of cancer locally at the tumor site.

Pump it up Carbon nanotube yarns can be used as electrochemical actuators because infiltration with ions causes a contraction in length and an expansion in diameter. Either positive or negative ions can cause this effect. Chu et al. constructed an all-solid-state muscle that eliminated the need for an electrolyte bath, which may expand the potential for its use in applications. By infiltrating the yarns with charged polymers, the fibers start partially swollen, so the length can increase through the loss of ions. It is thus possible to increase the overall stroke of the muscle. Further, these composite materials show a surprising increase in stroke with scan rate. Science , this issue p. 494

An investigation into the addition of different weight percentages of Fe

In this study we use a combination of ionic- and photo-cross-linking to develop a fabrication method for producing biocompatible microstructures using a methacrylated gellan gum (a polyanion) and chitosan (a polycation) in addition to lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) as the photoinitiator. This work involves the development of a low-cost, portable 3D bioprinter and a customized extrusion mechanism for controlled introduction of the materials through a 3D printed microfluidic nozzle, before being cross-linked in situ to form robust microstructure bundles. The formed microstructures yielded a diameter of less than 1 μm and a tensile strength range of ∼1 MPa. This study is the first to explore and achieve GGMA:CHT microstructure fabrication by means of controlled in-line compaction and photo-cross-linking through 3D printed microfluidic channels.

Biopolymer-based hydrogels have emerged as promising platforms for drug delivery systems (DDSs) due to their inherent biocompatibility, tunable physical properties and controllable degradability. Yet, drug release in majority of these systems is solely contingent on diffusion of drug molecules through the hydrogel, which often leads to burst release of drugs from these systems. Herein, inspired by the chemistry of mussel adhesive proteins, a new generation of coaxial hydrogel fibers was developed that could simultaneously exert both affinity and diffusion control over the release of chemotherapeutic drugs. Specifically, dopamine-modified alginate hydrogel along with chemotherapeutic drugs (doxorubicin or gemcitabine) was used as the main core component to confer affinity-controlled release, while a methacrylated-alginate hydrogel was used as the shell composition to provide the controlled diffusion barrier. It was shown that our coaxial mussel-inspired biofibers yielded biocompatible hydrogel fibers (as indicated by comprehensive in vitro and in vivo experiments) with favourable properties including controlled swelling, and enhanced mechanical properties, when compared against single fibers made from unmodified alginate. Notably, it was observed that these coaxial fibers were capable of releasing the two drugs in a slower manner, when compared to single fibers made from pure alginate, which was partly attributed to stronger interactions of drugs with dopamine-modified alginate (the core element of coaxial fibers) as observed from zeta-potential measurements. It was further shown that these drug-loaded coaxial fibers had optimal anticancer activity both in vitro and in vivo using various pancreatic cancer cell lines. Most remarkably, drug loaded coaxial fibers, particularly doxorubicin-containing fibers, had higher anticancer effect in vivo compared to systemic injection of equivalent dosage of the drugs. Altogether, these biocompatible and robust hydrogel fibers may be further used as neoadjuvant or adjuvant therapies for controlled delivery of chemotherapeutic drugs locally to the tumor sites.

Recent developments in miniaturized electronic devices with sophisticated computational capabilities and remarkably low power communication technologies involve a tendency toward powering these devices with long cycle life, high energy efficiency, fast and cheap production and lightweight power sources. Integration of piezoelectric materials and novel fabrication techniques with conventional textile processes established the emergence of a wearable technology field which can fulfill this purpose. Mechanical energy harvesters are required for multiple applications such as structural health monitoring systems, self-powered wireless sensors, and harvesting energy from body movements inexpensively. Among the variety of materials exhibiting piezoelectricity, polymers are more considered due to their many excellent properties desirable in flexible piezoelectric generators. Hence, fiber-based electronic devices have the best features for human garments such as flexibility, stretchability, permeability and lightweight, and they are ideal interface platform options between the environment, electronic devices and human body. Hence, this article starts with the fundamentals of wearable technology and materials involved and then reviews recent developments in fiber-based self-powered systems and sensors with the special focus on the piezoelectric poly(vinylidene fluoride) polymer and barium titanium oxide ceramic. In addition, a number of strategies that may improve the piezoelectric generator performance are summarized. Furthermore, the global textile market industry and the high-performance end-user such as washability and durability were reviewed. Potential difficulties, challenges and opportunities in the field of fiber-based energy generators are also explored.

With the aim of fabricating drug-loaded implantable patches, a 3D printing technique was employed to produce novel coaxial hydrogel patches. The core-section of these patches contained a dopamine-modified methacrylated alginate hydrogel loaded with a chemotherapeutic drug (Gemcitabine), while their shell section was solely comprised of a methacrylated alginate hydrogel. Subsequently, these patches were further modified with CaCO3 cross linker and a polylactic acid (PLA) coating to facilitate prolonged release of the drug. Consequently, the results showed that addition of CaCO3 to the formula enhanced the mechanical properties of the patches and significantly reduced their swelling ratio as compared to that for patches without CaCO3. Furthermore, addition of PLA coating to CaCO3-containing patches has further reduced their swelling ratio, which then significantly slowed down the release of Gemcitabine, to a point where 4-layered patches could release the drug over a period of 7 days in vitro. Remarkably, it was shown that 3-layered and 4-layered Gemcitabine loaded patches were successful in inhibiting pancreatic cancer cell growth for a period of 14 days when tested in vitro. Lastly, in vivo experiments showed that gemcitabine-loaded 4-layered patches were capable of reducing the tumor growth rate and caused no severe toxicity when tested in mice. Altogether, 3D printed hydrogel patches might be used as biocompatible implants for local delivery of drugs to diseased site, to either shrink the tumor or to prevent the tumor recurrence after resection. This study was supported by the Korean Health Technology R&D Project, Ministry of Health & Welfare, Republic of Korea (grant number: HI14C2640). This work was conducted with funding from the Illawarra Cancer Carers and the PanCare Foundation (APP1165978, administered by Cancer Australia) awarded to K.L.V. This study was funded by the Australian Research Council Center of Excellence for Materials Science (Grant No. CE140100012). The authors acknowledge funding from the Australian Research Council under Discovery Early Career Researcher award (J. Foroughi DE130100517).

Titanium dioxide (TiO2) and zinc oxide (ZnO) particles as photocatalysts are known to be effective in the degradation of various organic pollutants. Here we use a simple way of preparing an active TiO2 thin film for Malachite Green (MG) elimination from an aqueous solution based on a combination of advanced oxidation processes (electro Fenton and photocatalytic degradation) under UV wavelengths irradiation. The TiO2 and ZnO as nano-photocatalytic material as thin layers on the glass surface are applied. For the characterization of synthesized ZnO and TiO2 paste, SEM, TEM and XRD were used. The effects of operational variables on the degradation of MG were studied by central composite design (CCD). The results showed that MG was degraded by the TiO2 and ZnO pastes in photoelectro-Fenton system under UV irradiation at optimum conditions with 79.4 and 97.5% degradation efficiency, respectively, which reaction constant of thin film ZnO was 1.96 times as high as that of the TiO2 paste in the mentioned system. The optimum degradation conditions for thin film ZnO were as follows: pH of 3, 30 mg/L of initial MG concentration, 200 mA of electrical current, 0.4 mmol/L of FeCl3, and 16 min of contact time. In addition, the degradation rates of MG by both photocatalysts in the photoelectro-Fenton system could be explained in terms of the Langmuir-Hinshelwood pseudo-first-order kinetic equation.

Piezoelectric fibers have an important role in wearable technology as energy generators and sensors. A series of hybrid nanocomposite piezoelectric fibers of polyinylidene fluoride (PVDF) loaded with barium–titanium oxide (BT) and reduced graphene oxide (rGO) were prepared via the melt spinning method. Our previous studies show that high-performance fibers with 84% of the electroactive β-phase in the PVDF generated a peak output voltage up to 1.3 V and a power density of 3 W kg−1. Herein, the dynamic mechanical and creep behavior of these fibers were investigated to evaluate their durability and piezoelectric performance. Dynamic mechanical analysis (DMA) was used to provide phenomenological information regarding the viscoelastic properties of the fibers in the longitudinal direction. DSC and SEM were employed to characterize the crystalline structure of the samples. The storage modulus and the loss tangent increased by increasing the frequency over the temperature range (−50 to 150 °C) for all of the fibers. The storage modulus of the PVDF/rGO nanocomposite fibers had a higher value (7.5 GPa) in comparison with other fibers. The creep and creep recovery behavior of the PVDF/nanofillers in the nanocomposite fibers have been explored in the linear viscoelastic region at three different temperatures (10–130 °C). In the PVDF/rGO nanocomposite fibers, strong sheet/matrix interfacial interaction restricted the mobility of the polymer chains, which led to a higher modulus at temperatures 60 and 130 °C.

Background: Prostate cancer (PCa) is the third most diagnosed cancer among men in Iran with approximately 4200 new cases in 2015. Considering the rapid growth of cancer diagnosis, this study aims to investigate the economic burden of PCa patients and their health-related quality of life (HRQoL) Methods: A retrospective survey was conducted on 500 registered patients to discover the pattern of care and distribution of patients in the main treatment categories. In the next step, a multi-center survey of the patients under treatment was conducted. The objective of this survey was to estimate direct medical costs (DMC), non-medical costs, and productivity losses for patients and family members. HRQoL was measured by the Functional Assessment of Cancer Therapy–Prostate questionnaire. Results: Despite high age of patients (72±9.25 years), only 53.3% of them were retired or disabled. The largest proportion of patients (54.3%) received medicinal or surgical hormone therapy. Radical prostatectomy was the main treatment for 31.7% of patients, 10.2% received radiation therapy, and 3.8% underwent chemotherapy. DMC for incident population was approximately 12.5 million US dollars/year, and the highest average cost per capita belonged to chemotherapy patients. Unpredictably, productivity loss was nearly as much as direct cost. The mean score for HRQoL was 0.62±0.16 for all patients. Orchiectomy group had the lowest HRQoL score (0.55±0.16). Chemotherapy patients suffered the worst scores in the physical well-being subscale (0.47±0.24). Hormone therapy patients had the least scores in the prostate-specific subscale (0.50±0.18). Conclusion: The economic burden of PCa is estimated approximately 25.8 million US dollars per year for incident population. When we refer to the high proportion of patients diagnosed in advanced state of the disease and higher per capita cost for these patients, policy makers should promote screening strategies to control health care costs and to increase both life expectancy and HRQoL.

Actuator materials capable of producing a rotational or tensile motion are rare and, yet, rotary systems are extensively utilized in mechanical systems like electric motors, pumps, turbines and compressors. Rotating elements of such machines can be rather complex and, therefore, difficult to miniaturize. Rotating action at the microscale, or even nanoscale, would benefit from the direct generation of torsion from an actuator material. Herein we discuss the advantages of using carbon nanotube (CNT) yarns and/or graphene (G) fibers as novel artificial muscles that have the ability to be driven by the electrochemical charging of helically wound multiwall carbon nanotubes or graphene fibers as well as elements in the ambient environment such as moisture to generate such rotational action. The torsional strain, torque, speed and lifetime have been evaluated under various electrochemical conditions to provide insight into the actuation mechanism and performance. Here the most recent advances in artificial muscles based on sheath-run artificial muscles (SRAMs) are reviewed. Finally, the rotating motion of the CNT yarn actuator and the humidity-responsive twisted graphene fibers have been coupled to a mixer for use in a prototype microfluidic system, moisture management and a humidity switch respectively.

Today we associate wearable technologies with electronic devices and novel approaches for powering these devices are being enabled by the advent of new piezoelectric materials and novel fabrication strategies. Mechanical energy harvesters are needed for such diverse applications as self-powered wireless sensors, structural and human health monitoring systems, and cheaply harvesting energy from human movements. Herein, we demonstrate novel triaxial braided PVDF yarn harvesters that piezoelectrically convert tensile mechanical energy into electrical energy. Compressing or bending braided PVDF yarns generated a maximum output voltage of 380 mV and a power density of 29.62 μW cm−3 which is ∼1559% higher than previously reported for piezoelectric textiles. It is found that the developed triaxial energy generator exhibits significantly higher sensitivity by a factor of 4 compared with the PVDF energy generator. Unlike other piezoelectric harvesters, the triaxial braided PVDF yarn achieves tensile energy harvesting and shows extreme durability which enables cycling with up to 50% strain for thousands of cycles with no changes in its performance. The production process is compatible with industrial, large-scale textile manufacturing and can be used for a variety of potential applications such as wearable electronic systems and energy harvesters charged from everyday body movements.

Smart materials are capable of recognising environmental stimuli, processing the information arising from the stimuli, and responding to it in an appropriate manner. It is well known that smart textiles provide some interesting possibilities in this regard. Consequently, smart textiles based on artificial muscles polymer actuators will provide a breakthrough to many areas including soft robotics, prosthetics, and healthcare for the benefit of humankind. Therefore, it is a worthy attempt to work on artificial muscle designs to aid them in applications. This paper presents the effect of fibre arrangement within a material structure for force and stroke generation. A method of fabrication, characterisation of actuating textiles was presented with experimental results. Most importantly, a modelling was carried out to develop equations to calculate the force and stroke of actuating textiles which has not been reported to date. A reasonable agreement was found between calculated and measured force/stroke curves of both woven and knitted textiles. The woven textile exhibited a force enhancement directly proportional to the number of actuators while retaining the same strain of the single actuator. Nonetheless, the force and strain of knitted textile were highly dependent on the number of wales and courses per unit length. The fabricated knitted textile showed a lesser strain than the single actuator with a force amplification. However, the performance parameters of as fabricated knitted textiles were higher than the fabricated woven textile. Finally a practical applications, process for bulk manufacturing of silicone coated actuators was proposed to enable them in commercialised products and long length production. This study will enable developers to select the fibre architectures and suitable actuators to suit a particular end requirement.

The ubiquity of wearables, coupled with the increasing demand for power, presents a unique opportunity for nanostructured fiber-based mobile energy storage systems. When designing wearable electronic textiles, there is a need for mechanically flexible, low-cost and light-weight components. To meet this demand, we have developed an all-in-one fiber supercapacitor with a total thickness of less than 100 &mu, m using a novel facile coaxial wet-spinning approach followed by a fiber wrapping step. The formed triaxial fiber nanostructure consisted of an inner poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) core coated with an ionically conducting chitosan sheath, subsequently wrapped with a carbon nanotube (CNT) fiber. The resulting supercapacitor is highly flexible, delivers a maximum energy density 5.83 Wh kg&minus, 1 and an extremely high power of 1399 W kg&minus, 1 along with remarkable cyclic stability and specific capacitance. This asymmetric all-in-one fiber supercapacitor may pave the way to a future generation of wearable energy storage devices.

Artificial muscle plays an interesting role in science discoveries. Large scale torsional and tensile actuation is achieved by twisting and coiling of synthetic polymer fibres. Research reports to date have discussed the theoretical background of actuation of twisted monofilament yarn. Twisting and coiling of several yarns together is another approach to fabricate polymer actuators and here we present the experimental observations of performance of actuators fabricated with multiple number of yarns. The theoretical background for the reasons of decreasing the actuation performance with increasing number of yarns are critically analysed and presented in this study. This analysis concludes that a minor change in the length of the fibre can significantly affect the stroke and force values of the twisted polymer actuators.

In this paper, a sewed chipless octagonal-shaped RFID tag on cotton fabric is proposed for wearable applications. The tag is designed using a Frequency Selective Surface (FSS) technique and operates from 8-18GHz. The design is composed of six concentric octagonal loop resonators with one unitary element. The tag is made of silver-coated polyamide conductive fiber (HC12) and is manufactured using a commercial ZSK Technical Embroidery System JCZA. The encoded data bits are obtained by a series of Radar Cross Section (RCS) measurements inside an anechoic chamber. The experimental results obtained show that the 4-bit data codeword is accurately retrieved up to 1.8m away from the tag at 0dBm power. Moreover, the feasibility of the proposed tag for wearable and smart garment IoT applications is verified by on-body RCS measurements.

The demands for wearable technologies continue to grow and novel approaches for powering these devices are being enabled by the advent of new energy materials and novel manufacturing strategies. In addition, decreasing the energy consumption of portable electronic devices has created a huge demand for the development of cost-effective and environment friendly alternate energy sources. Energy harvesting materials including piezoelectric polymer with its special properties make this demand possible. Herein, we develop a flexible and lightweight nanogenerator package based on polyvinyledene fluoride (PVDF)/LiCl electrospun nanofibers. The piezoelectric performance of the developed nanogenator is investigated to evaluate effect of the thickness of the as-spun mat on the output voltage using a vibration and impact test. It is found that the output voltage increases from 1.3 V to 5 V by adding LiCl as additive into the spinning solution compared with pure PVDF. The prepared PVDF/LiCl nanogenerator is able to generate voltage and current output of 3 V and 0.5 &mu, A with a power density output of 0.3 &mu, W cm&minus, 2 at the frequency of 200 Hz. It is found also that the developed nanogenerator can be utilized as a sensor to measure temperature changes from 30 &deg, C to 90 &deg, C under static pressure. The developed electrospun temperature sensor showed sensitivity of 0.16%/&deg, C under 100 Pa pressure and 0.06%/&deg, C under 220 Pa pressure. The obtained results suggested the developed energy harvesting textiles have promising applications for various wearable self-powered electrical devices and systems.

Delivery of therapeutic agents directly to the diseased sites is of utmost importance in efficient treatments of various diseases. Along the same lines, implantable drug delivery systems (DDSs) made from biocompatible polymers showed great promise in locally treating diseases such as cancer. To this end, these DDSs can offer on-demand delivery of drugs in response to various environmental factors (such as temperature or pH) or external stimuli (such as electromagnetic waves, laser pulses). Consequently, in this chapter a comprehensive review of biopolymeric implantable DDSs, with special focus on intelligent DDSs, for treating variety of diseases is provided.

Electrochemically or electrothermally driven twisted/coiled carbon nanotube (CNT) yarn actuators are interesting artificial muscles for wearables as they can sustain high stress. However, due to high fabrication costs, these yarns have limited their application in smart textiles. An alternative approach is to use off-the-shelf yarns and coat them with conductive polymers that deliver high actuation properties. Here, novel hybrid textile yarns are demonstrated that combine CNT and an electroactive polypyrrole coating to provide both high strength and good actuation properties. CNT-coated polyester yarns are twisted and coiled and subjected to electrochemical coating of polypyrrole to obtain the hierarchical soft actuators. When twisted without coiling, the polypyrrole-coated yarns produce fully reversible 25 degrees mm(-1)rotation, 8.3x higher than the non-reversible rotation from twisted CNT-coated yarns in a three-electrode electrochemical system operated between +0.4 and -1.0 V (vs Ag/AgCl). The coiled yarns generate fully reversible 10 degrees mm(-1)rotation and 0.22% contraction strain, 2.75x higher than coiled CNT-coated yarns, when operated within the same potential window. The twisted and coiled yarns exhibit high tensile strength with excellent abrasion resistance in wet and dry shearing conditions that can match the requirements for using them as soft actuators in wearables and textile exoskeletons. Funding Agencies|Promobilia Foundation [F17603]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (faculty grant SFO Mat LiU) [2009-00971]; Swedish Research CouncilSwedish Research Council [2014-3079]; Carl Trygger Foundation [CTS:17-215]; European Unions Horizon 2020 research and innovation program [825232]; University of Wollongongs Visiting International Scholar Award

A new concept for tensile artificial muscles is introduced in which the torsional actuation of a twisted polymer fibre drives a twist to writhe conversion in a serially attached elastomeric fibre. Thermally induced torsional rotation of the twisted fibre caused formation of coils in the elastomeric fibre which resulted in overall muscle length contraction. Theoretical predictions of the muscle strain were developed by means of a modified single-helix theory. Experimental tests were conducted to measure the isotonic contraction strains for elastomeric fibres of different diameters and lengths. A good agreement between the measured and calculated results was found. Practical applicability of this muscle is evaluated by using different mechanical loading conditions. Actuation contraction strains as high as 10% were observed with excellent reversibility. Unlike original coiled fibre tensile actuators, these twist-coil artificial muscles did not require any pre-conditioning cycles. (C) 2018 Elsevier B.V. All rights reserved.

Carbon nanotube (CNT) yarns are novel CNT-based materials that extend the advantages of CNT from the nanoscale to macroscale applications. Herein we have modeled the electrical properties of carbon nanotube yarn as a function of temperature and magnetic field. The conductivity was well explained by 3D Mott Variable Range Hopping (VRH) law at T