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AixSense 2019

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== Method ==
Electro-Impedance Spectroscopy (EIS). Anti-Adalimumab (Anti-AM) is used to immobilize the surface of the graphene based transducers where the analyte then flowed flows over. Changes in the impedance before and after the flow are measured using an Impedance Analyzer. Adalimumab specific transducers will then show increase of impedance against different concentrations of Adalimumab molecular binding within clinical ranges (0.1μg/ml to 10 μg/ml).
== Physical Transduction ==
The graphene based transducers allows for electrical readouts for the specific binding of AM and the optical readout for the recording of optical emissions from the labelled secondary antibodies of TNF- alpha which specifically binds to the Anti-AM AM complex bio that are immobilized on the Graphene transducers. Moreover, dedicated microfluidic circuits increasing the local concentrations of the analytes at the transducer enhance the optical signal and improve the bioassay readout.
Differential pulse voltammetry (DPV) is used for the readout and anequimolar mixture of the potassium ferricyanide/ferrocyanide redox couple acts An optical based detection has also been installed as a probe parallel detection platform for increased accuracy of the signal generationresults. The current is measured as a function of time and potential between For the indicator and reference electrode. As the potential increases towards the redox potential of the probeoptical detection, it starts undergoing redox and a current up to a peak value Microscale Thermophoresis (MST) is producedutilised. The current is subsequently brought into a diffusion-controlled state and as a result, the total current response takes its shape as a peak. The immunocomplex restricts the surface availability for the redox probe, which lowers the number Directed movement of redox events and therefore reduces the current signal.Measurements are performed after the immobilization procedure to achieve particles in a baseline which is compared microscopic temperature gradient leads to the signal obtained after analyte incubation on the electrode.Samples with known concentrations accumulation of the analyte are used molecules and thus leads to prepare a calibration curve which can then be used an enhanced sensor signal due to quantify the amount of the analyte in an unknown sampleincreased local fluorescence.
== Cartridge ==
The screen-printed electrodes are disposable. Incubation For measuring the concentration of AM, blood samples containing the sample on the electrode isdrug are injected intoperformed outside of the potentiostat. The sample is applied by disposable chips (having graphene electrodes functionalized with Anti-AM) and then the technician on the tabletop after which the sample optically labelled TNFα is incubated in a sealed container in 4 degree celsiusmade to flow through it. After sample incubation, Once the electrode fluid is manually washed off with PBS into a waste container. The electrode is inserted into stationary, the adapter on electrical and optical measurements are made in the potentiostat respective platforms and quantification can be performed. After running the chips are disposed after each measurement, the electrode cansimply be discarded into biological waste. The electrode chips could potentially be regenerated and therefore, reused.
== Reader Instrument ==
The size of the biosensor entire setup is 95mmx75mmx75mm. It consists of a sealedpotentiostat and an electrode chip. The only handling required by the user is related to the electrode chip. The output of the measurement can be viewed and analyzed with the PSTrace software (PalmSens).The data from known concentrations of the analyte can be used to externally produce a calibration curve which can then be used to infer the analyte concentrations of an unknown sample based on peak differences20x20x40 cm^3 in dimensions.Additionally, an app has been developed which can measure the raw data in real-time during the measurement using Bluetooth. The data obtained can be automatically converted to the concentration of adalimumab in blood. The app provides graphs on current and past measurements, making the interpretation of the optimal drug usage straightforward to assess.
== Prizes==The user administers the blood sample and TNFα in the chip and put the chip in the measurement system. The electrical readout is then measured using an Impedance Analyzer, where the impedance change obtained at a particular frequency will indicate the concentrations. The optical readout is an image of the fluorescence captured by the camera.Furthermore, there is an integrated optoelectronic read out platform in order to improve the accuracy and speed of measurement.