A new kind of potassium sensor based on capacitance measurement of mimic membrane

A novel type of potassium sensor based on the capacitance change of valinom ycin-incorporated bilayer supported on a gold electrode has been developed and characterized. The lipid membrane was Formed by painted method and moni tored simultaneously by capacitance variation. The capacitance of the elect rode-supported membrane was found to be modulated by different concentratio ns of K+. Investigating the capacitance change allows a simple and specific technique for the measurement of potassium ion in solution. Especially, th e homemade capacitance meter is, to our knowledge, used to monitor the bila yer membrane formation and detect K+ for the first time. It has been proved that this capacitance measurement is a very useful technique because it is simple and sensitive compared to the other methods.