Flexible Superwettable Tapes for On-Site Detection of Heavy Metals

Bioinspired superwettable micropatterns that combine superhydrophobicity and superhydrophilicity have been proved to exhibit outstanding capacity in controlling and patterning microdroplets and possessed new functionalities and possibilities in emerging sensing applications. Here, we introduce a flexible tape-based superhydrophilic–superhydrophobic tape toward on-site heavy metals monitoring. On such a superwettable tape, capillarity-assisted superhydrophilic microwells allow directly anchoring indicators in fixed locations and sampling into a test zone via simple dip-pull from an origin specimen solution. In contrast, the superhydrophobic substrate could confine the microdroplets in the superhydrophilic microwells for reducing the amount of analytical solution. The tape-based microchip also displays excellent flexibility against stretching, bending, and torquing for expanding wearable and portable sensing devices. Qualitative and quantitative colorimetric assessments of multiplex heavy metal analyses (chromium, copper, and nickel) by the naked eye are also achieved. The superwettable tape-based platforms with a facile operation mode and accessible signal read-out represent unrevealed potential for on-site environmental monitoring

Flexible Superwettable Tapes for On-Site Detection of Heavy Metals

Bioinspired superwettable micropatterns that combine superhydrophobicity and superhydrophilicity have been proved to exhibit outstanding capacity in controlling and patterning microdroplets and possessed new functionalities and possibilities in emerging sensing applications. Here, we introduce a flexible tape-based superhydrophilic–superhydrophobic tape toward on-site heavy metals monitoring. On such a superwettable tape, capillarity-assisted superhydrophilic microwells allow directly anchoring indicators in fixed locations and sampling into a test zone via simple dip-pull from an origin specimen solution. In contrast, the superhydrophobic substrate could confine the microdroplets in the superhydrophilic microwells for reducing the amount of analytical solution. The tape-based microchip also displays excellent flexibility against stretching, bending, and torquing for expanding wearable and portable sensing devices. Qualitative and quantitative colorimetric assessments of multiplex heavy metal analyses (chromium, copper, and nickel) by the naked eye are also achieved. The superwettable tape-based platforms with a facile operation mode and accessible signal read-out represent unrevealed potential for on-site environmental monitoring

Vapor-Driven Propulsion of Catalytic Micromotors

Chemically-powered micromotors offer exciting opportunities in diverse fields, including therapeutic delivery, environmental remediation, and nanoscale manufacturing. However, these nanovehicles require direct addition of high concentration of chemical fuel to the motor solution for their propulsion. We report the efficient vapor-powered propulsion of catalytic micromotors without direct addition of fuel to the micromotor solution. Diffusion of hydrazine vapor from the surrounding atmosphere into the sample solution is instead used to trigger rapid movement of iridium-gold Janus microsphere motors. Such operation creates a new type of remotely-triggered and powered catalytic micro/nanomotors that are responsive to their surrounding environment. This new propulsion mechanism is accompanied by unique phenomena, such as the distinct off-on response to the presence of fuel in the surrounding atmosphere, and spatio-temporal dependence of the motor speed borne out of the concentration gradient evolution within the motor solution. The relationship between the motor speed and the variables affecting the fuel concentration distribution is examined using a theoretical model for hydrazine transport, which is in turn used to explain the observed phenomena. The vapor-powered catalytic micro/nanomotors offer new opportunities in gas sensing, threat detection, and environmental monitoring, and open the door for a new class of environmentally-triggered micromotors

Flexible and superwettable bands as a platform toward sweat sampling and sensing

Wearable biosensors as a user-friendly measurement platform have become a rapidly growing field of interests due to their possibility in integrating traditional medical diagnostics and healthcare management into miniature lab-on-body analytic devices. This paper demonstrates a flexible and skin-mounted band that combines superhydrophobic-superhydrophilic microarrays with nanodendritic colorimetric biosensors toward in situ sweat sampling and analysis. Particularly, on the superwettable bands, the superhydrophobic background could confine microdroplets into superhydrophilic microwells. On-body investigations further reveal that the secreted sweat is repelled by the superhydrophobic silica coating and precisely collected and sampled onto the superhydrophilic micropatterns with negligible lateral spreading, which provides an independent “vessel” toward cellphone-based sweat biodetection (pH, chloride, glucose and calcium). Such wearable, superwettable band-based biosensors with improved interface controllability could significantly enhance epidemical sweat sampling in well-defined sites, holding a great promise for facile and noninvasive biofluids analysis

Flexible and superwettable bands as a platform toward sweat sampling and sensing

Wearable biosensors as a user-friendly measurement platform have become a rapidly growing field of interests due to their possibility in integrating traditional medical diagnostics and healthcare management into miniature lab-on-body analytic devices. This paper demonstrates a flexible and skin-mounted band that combines superhydrophobic-superhydrophilic microarrays with nanodendritic colorimetric biosensors toward in situ sweat sampling and analysis. Particularly, on the superwettable bands, the superhydrophobic background could confine microdroplets into superhydrophilic microwells. On-body investigations further reveal that the secreted sweat is repelled by the superhydrophobic silica coating and precisely collected and sampled onto the superhydrophilic micropatterns with negligible lateral spreading, which provides an independent “vessel” toward cellphone-based sweat biodetection (pH, chloride, glucose and calcium). Such wearable, superwettable band-based biosensors with improved interface controllability could significantly enhance epidemical sweat sampling in well-defined sites, holding a great promise for facile and noninvasive biofluids analysis

Turning Erythrocytes into Functional Micromotors

Attempts to apply artificial nano/micromotors for diverse biomedical applications have inspired a variety of strategies for designing motors with diverse propulsion mechanisms and functions. However, existing artificial motors are made exclusively of synthetic materials, which are subject to serious immune attack and clearance upon entering the bloodstream. Herein we report an elegant approach that turns natural red blood cells (RBCs) into functional micromotors with the aid of ultrasound propulsion and magnetic guidance. Iron oxide nanoparticles are loaded into the RBCs, where their asymmetric distribution within the cells results in a net magnetization, thus enabling magnetic alignment and guidance under acoustic propulsion. The RBC motors display efficient guided and prolonged propulsion in various biological fluids, including undiluted whole blood. The stability and functionality of the RBC motors, as well as the tolerability of regular RBCs to the ultrasound operation, are carefully examined. Since the RBC motors preserve the biological and structural features of regular RBCs, these motors possess a wide range of antigenic, transport, and mechanical properties that common synthetic motors cannot achieve and thus hold considerable promise for a number of practical biomedical uses

Materials systems and autonomy in electromechanical sound art

Sound art is a difficult to categorise and broad genre description that draws together modes of creative practice which use sound as a medium or a subject. The field is considered to be critically underrepresented and under-theorised despite an increase of attention and popularity since the 1990s (Licht 2007, 2001, Cox 2009). This is partly as a consequence of an analytical and historical emphasis on textual and conceptual approaches which dominated the arts through the 1970s and 1980s (Cox 2011, 2013). In particular, acknowledgement of the influence of object-based and kinetic sculpture within the field of sound art is found to be inadequate (Chau 2014, Keylin 2015). This thesis presents an original body of sound art practice as a means through which to uncover and explore connections between sound art, experimental composition, kinetic art and sculpture. The term 'electromechanical' is used to identify this work, highlighting its particular concerns with the use of electrically animated or amplified materials. Through the production, exhibition, critical appraisal and contextualisation of the work new observations and distinctions within the field are presented. These include the identification of a 'closed system aesthetic' and the distinction between robotic and process driven approaches to electromechanical sound art. A further contribution to the field consists of a detailed consideration of sound art emerging from an intersection of experimental music and sculptural practices during the 1960s. The original works produced for the project, and their production are documented and described in detail alongside existing canonical and contemporary examples of sound art. Analysis of these works is informed by materialist and object-orientated critical positions, and science and technology studies. The method of art practice as research is described and extended in an original way that encompasses and applies a systems approach to creative practice

Vapor-Driven Propulsion of Catalytic Micromotors

Chemically-powered micromotors offer exciting opportunities in diverse fields, including therapeutic delivery, environmental remediation, and nanoscale manufacturing. However, these nanovehicles require direct addition of high concentration of chemical fuel to the motor solution for their propulsion. We report the efficient vapor-powered propulsion of catalytic micromotors without direct addition of fuel to the micromotor solution. Diffusion of hydrazine vapor from the surrounding atmosphere into the sample solution is instead used to trigger rapid movement of iridium-gold Janus microsphere motors. Such operation creates a new type of remotely-triggered and powered catalytic micro/nanomotors that are responsive to their surrounding environment. This new propulsion mechanism is accompanied by unique phenomena, such as the distinct off-on response to the presence of fuel in the surrounding atmosphere, and spatio-temporal dependence of the motor speed borne out of the concentration gradient evolution within the motor solution. The relationship between the motor speed and the variables affecting the fuel concentration distribution is examined using a theoretical model for hydrazine transport, which is in turn used to explain the observed phenomena. The vapor-powered catalytic micro/nanomotors offer new opportunities in gas sensing, threat detection, and environmental monitoring, and open the door for a new class of environmentally-triggered micromotors

Cell-Membrane-Coated Synthetic Nanomotors for Effective Biodetoxification

A red blood cell membrane-camouflaged nanowire that can serve as new generation of biomimetic motor sponge is described. The biomimetic motor sponge is constructed by the fusion of biocompatible gold nanowire motors and RBC nanovesicles. The motor sponge possesses a high coverage of RBC vesicles, which remain totally functional due to its exclusively oriented extracellular functional portion on the surfaces of motor sponge. These biomimetic motors display efficient acoustical propulsion, including controlled movement in undiluted whole blood. The RBC vesicles on the motor sponge remain highly stable during the propulsion process, conferring thus the ability to absorb membrane-damaging toxins and allowing the motor sponge to be used as efficient toxin decoys. The efficient propulsion of the motor sponges under an ultrasound field results in accelerated neutralization of the membrane-damaging toxins. Such motor sponges connect artificial nano­motors with biological entities and hold great promise for treating a variety of injuries and diseases caused by membrane-damaging toxins

Cell-Membrane-Coated Synthetic Nanomotors for Effective Biodetoxification

A red blood cell membrane-camouflaged nanowire that can serve as new generation of biomimetic motor sponge is described. The biomimetic motor sponge is constructed by the fusion of biocompatible gold nanowire motors and RBC nanovesicles. The motor sponge possesses a high coverage of RBC vesicles, which remain totally functional due to its exclusively oriented extracellular functional portion on the surfaces of motor sponge. These biomimetic motors display efficient acoustical propulsion, including controlled movement in undiluted whole blood. The RBC vesicles on the motor sponge remain highly stable during the propulsion process, conferring thus the ability to absorb membrane-damaging toxins and allowing the motor sponge to be used as efficient toxin decoys. The efficient propulsion of the motor sponges under an ultrasound field results in accelerated neutralization of the membrane-damaging toxins. Such motor sponges connect artificial nano­motors with biological entities and hold great promise for treating a variety of injuries and diseases caused by membrane-damaging toxins