US Patent 7547382 Determination of partial fill in electrochemical strips

Partial fill of an electrochemical test strip is determined by making a DC determination of double layer capacitance from charging or discharging charge on a test strip containing sample, for example a blood sample to be tested for glucose. The measured double layer capacitance is compared to a reference value. The double layer capacitance may be determined as an integral or differential capacitance. Double layer capacitance may also be used for quality control to monitor the quality of electrode formation, particularly in strips using screen printed electrodes.