Mortality rates of up to 50% have been reported after liver failure due to drug-induced hepatotoxicity and certain viral infections (Gao et al. 2008). These adverse conditions frequently affect HIV and tuberculosis patients on regular medication in resource-poor settings. Here, we report full integration of sample preparation with read-out of a 5-parameter liver assay panel (LAP) on a portable, easy-to-use, fast and costefficient centrifugal microfluidic analysis system (CMAS). Our unique, dissolvable-film based centrifugopneumatic valving was employed to provide sample-to-answer fashion automation for plasma extraction (from finger-prick of blood), metering and aliquoting into separate reaction chambers for parallelized colorimetric quantification during rotation. The entire LAP completes in less than 20 minutes while using only a tenth the reagent volumes when compared with standard hospital laboratory tests. Accuracy of in-situ liver function screening was validated by 96 separate tests with an average coefficient of variance (CV) of 7.9% compared to benchtop and hospital lab tests. Unpaired two sample statistical t-tests were used to compare the means of CMAS and benchtop reader, on one hand; and CMAS and hospital tests on the other. The results demonstrate no statistical difference between the respective means with 94% and 92% certainty of equivalence, respectively. The portable platform thus saves significant time, labour and costs compared to established technologies, and therefore comply with typical restrictions on lab infrastructure, maintenance, operator skill and costs prevalent in many field clinics of the developing world. It has been successfully deployed in a centralised lab in Nigeria. IntroductionLiver is the largest solid organ in the body and is largely responsible for metabolism and detoxification. (Gao et al. 2008) Liver function tests are widely used in clinical chemistry to assess therapeutic effects and potential medication-induced liver damage, especially when taking medications for HIV, tuberculosis and cancer. (Landis et al. 2013;Rahmioglu et al. 2009; Vella et al. 2012) Literature reports suggest that a mortality rate of 2 -28% can be linked with medication-induced liver damage. (Vella et al. 2012) As a result, monitoring of liver function when on certain medications has become common practice in developed countries but can be expensive in poor resource areas. This has prompted local governments and international funding agencies to set up centralised laboratories for liver function monitoring tests especially for HIV patients. Nonetheless, transport logistics and accessibility remains a significant challenge for the majority of these patients. Thus it is very important to develop portable point-of-care (PoC) devices that could be used for liver function screening in the field. Currently, there are only a handful of sample-to-answer PoC devices available for deployment in the field. Recently, Vella et al.(Vella et al. 2012) demonstrated an innovative micropatterned paper device fo...

This work describes the first use of a wireless paired emitter detector diode device (PEDD) as an optical sensor for water quality monitoring in a lab-on-a-disc device.The microfluidic platform, based on an ionogel sensing area combined with a lowcost optical sensor is applied for pH (quantitative) and qualitative turbidity monitoring of water samples at the point-of-need. The autonomous capabilities of the PEDD system, combined with the portability and wireless communication of the full device, provide the flexibility needed for on-site water testing. Water samples from local fresh and brackish sources were successfully analysed using the device, showing very good correlation with standard bench-top systems.

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. KeywordsStimuli responsive, photo-responsive, microstructures, photo-patterning, ionogel, ionic liquid. Page 2 of 38A c c e p t e d M a n u s c r i p t 2 AbstractPhotoresponsive N-isopropylacrylamide ionogel microstructures are presented in this study. These ionogels are synthesised using phosphonium based room temperature ionic liquids, together with the photochromic compound benzospiropyran. The microstructures can be actuated using light irradiation, facilitating non-contact and non-invasive operation. For the first time, the characterisation of the swelling and shrinking behaviour of several photopatterned ionogel microstructures is presented and the influence of surface-area-to-volume ratio on the swelling kinetics is evaluated. It was found that the swelling and shrinking behaviour of the ionogels is strongly dependent on the nature of the ionic liquid. In particular, the [P 6,6,6,14 ][NTf 2 ] ionogel exhibits the greatest degree of swelling, reaching up to 180 % of its initial size, and the fastest shrinkage rate (k sh = 29 ± 4 x 10 -2 s -1 ).

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New generations of chemical sensors require both innovative (evolutionary) engineering concepts and (revolutionary) breakthroughs in fundamental materials chemistry, such as the emergence of new types of stimuli responsive materials. Intensive research in those fields in recent years have brought interesting new concepts and designs for microfluidic flow control and sample handling that integrate high quality engineering with new materials. In this paper we review recent developments in this fascinating area of science, with particular emphasis on photoswitchable soft actuators and their incorporation into fluidic devices that are increasingly biomimetic in nature.

A portable, wireless system capable of in-situ reagent-based colorimetric analysis is demonstrated. The system is based on a reconfigurable low cost optical detection method employing a paired emitter detector diode device, which allows a wide range of centrifugal microfluidic layouts to be implemented. Due to the wireless communication, acquisition parameters can be controlled remotely and results can be downloaded in distant locations and displayed in real time. The stand-alone capabilities of the system, combined with the portability and wireless communication, provide the flexibility crucial for on-site water monitoring.The centrifugal microfluidic disc presented here is designed for nitrite detection in water samples, as a proof of principle. A limit of detection of 9.31 ppb, along with similar coefficient of correlation and precision, were obtained from the Centrifugal Microfluidic Analysis System compared with the same parameters measured using a UV-Vis spectrophotometer.

This paper describes the design, fabrication and performance of a reusable ionogel-based photoactuator, in-situ photopolymerised into a lab-on-a-disc microfluidic device, for flow control. The the ionogel provides an effective barrier to liquids during storage of reagents and spinning of the disc. A simple LED (white light) triggers actuation of the ionogel for selective and precise channel opening at a desired location and time. The mechanism of actuation is reversible, and regeneration of the actuator is possible with an acid chloride solution. In order to achieve regeneration, the Lab-on-a-Disc device was designed with a microchannel connected perpendicularly to the bottom of the ionogel actuator (regeneration channel). This configuration allows the acid solution to reach the actuator, independently from the main channel, which initiates ionogel swelling and main channel closure, and thereby enables reusability of the whole device.

Despite significant advances in the development of artificial heart substitutes, anthrombogenic materials and surfaces remain to be the main challenge for implants, which can prevent thrombosis that leads to rejection. The goal of material engineering is essentially to design polymeric materials of high durability and optimal thrombogenicity in mechanical heart prosthesis, being developed recently in a frame of the polish artificial heart program. For these reasons, various surface modifications are being continuously developed for a 'gold standard' material, which is a polyurethane (PU) thermoplastic elastomer and they will be shortly reviewed. However, new polymeric materials can meet medical word's attention if they are able to provide similar or better characteristics in term of bulk and surface properties. Specifically, if they will show appropriate surface topography, which is the most influential in determining the response of live tissues toward biomaterials. Nanostructured polyester thermoplastic elastomers of high biodurability as an alternative to PU materials for artificial heart are challenging new materials, and they will be discussed briefly.