Development of a new MOF based potentiometric sensor for Cysteamine determination

A potentiometric PVC membrane ion selective sensor (ISE) was developed to determination of cysteamine. In the structure of the sensor, a metal organic framework structure (MOF) was used as an ionophore. Basolite C300 was used as the metal organic framework. The optimized membrane composition includes 6.0% Basolite C300, 67.0% o-nitrophenyl octyl ether (o-NPOE), 26.0% polyvinyl chloride (PVC) and 1.0% potassium tetrakis(4-chlorophenyl)borate (KTpClPB) and the sensor formed with this membrane composition showed superior potentiometric performance properties. The sensor exhibited a linear response to cysteamine concentrations ranging from 1.0×10−6 mol L-1 to 1.0×10−2 mol L-1 (R2=0.9958) in aqueous solutions, with a slope of 51.5 mV/decade and a limit of detection of 8.0×10−7 mol L-1 . The pH operating range was determined to be 3.2-9.1 and the response time was determined to be under 10 seconds.The sensor can also operate for nine weeks without significant loss of sensitivity. The repeatability of the developed sensor is quite high. The produced cysteamine selective sensor was applied quite successfully in pharmaceutical formulation.