Paper-based galvanic cell for application in paper microfluidics

Abstract

U radu je prikazana izvedba papirnatog galvanskog članka prikladnog za uporabu u papirnatim mikrofluidičkim analitičkim napravama. Izrađeni galvanski članak sastojao se od grafitne katode izrađene crtanjem po papiru mekom grafitnom olovkom i aluminijske anode izrađene od samoljepljive aluminijske folije. Rad članka temeljio se na oksidaciji aluminijske anode i redukciji ABTS radikala, in situ generiranog u članku, oksidacijom ABTS-a s vodikovim peroksidom u prisutnosti željezova(II) ftalocijanina kao katalizatora. Sve komponente potrebne za rad konstruiranog galvanskog članka, uključujući i vodikov peroksid u formi urea peroksida, unaprijed su pohranjene u članku u obliku krutina pa je za pokretanje članka dovoljno u njega dodati mali volumen vode. Pri optimalnim uvjetima, konstruirani galvanski članak u stanju je davati struju od približno 0,1 mA, uz napon od 1 V, tijekom perioda od otprilike 30 minuta, što ga čini prikladnim za napajanje potencijalnih papirnatih mikrofluidičkih analitičkih naprava s integriranim elektroničkim sklopovima za obradu signala i prikaz rezultata mjerenja.In this work, a paper-based galvanic cell suitable for application in microfluidic paper-based analytical devices is described. The galvanic cell comprises of a graphite cathode fabricated by drawing on the paper with a soft graphite pencil and an aluminium anode, fabricated from self-adhesive aluminium foil. Operational mode of the cell was based on the oxidation of the aluminium anode and the reduction of the ABTS radical, generated in situ, inside the cell, by oxidizing ABTS with hydrogen peroxide in the presence of iron(II) phthalocyanine as a catalyst. All of the components required for the operation of the constructed galvanic cell, including hydrogen peroxide in the form of urea peroxide, were stored in advance inside the cell in the form of powdered solid, so the operation of the galvanic cell can be initiated simply by adding a small volume of water into the cell. Under optimal conditions, the constructed galvanic cell produced an electric current of approximately 0.1 mA and a voltage of 1 V, during a period of around 30 minutes, which makes it suitable for powering of microfluidic paper-based analytical devices with integrated electronic circuits for signal processing and displaying measurement results