Underfill detection method for an electrochemical biosensor

• Main Authors: MUSHO, MATTHEW K, EDELBROCK, ANDREW J, NOELL, OAKEY J
• Format: Patent
• Language: English; French; German
• Published: 09.02.2011
• Subjects: BEER; BIOCHEMISTRY; CHEMISTRY; COMPOSITIONS OR TEST PAPERS THEREFOR; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL ORENZYMOLOGICAL PROCESSES; ENZYMOLOGY; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; MEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEICACIDS OR MICROORGANISMS; METALLURGY; MICROBIOLOGY; MUTATION OR GENETIC ENGINEERING; PHYSICS; PROCESSES OF PREPARING SUCH COMPOSITIONS; SPIRITS; TESTING; VINEGAR; WINE

Disclosed is a method of determining whether a sufficient quantity of a fluid test sample has been introduced to an electrochemical sensor having a base bearing a working and reference electrode which provides a flow path for the fluid test sample. The working electrode has a reaction layer on its surface which contains an enzyme capable of reacting with an analyte to produce electrons which are received by the working electrode. The base is mated with a cover to form a capillary space into which the test fluid is drawn. The improvement involves configuring the working and reference electrodes so that a major portion of the reference electrode is located downstream on the flow path from the working electrode with the exception of a small sub-element of the reference electrode which is in electrical communication with the primary portion of the reference electrode and located upstream of the working electrode. This configuration provides the sensor with the capability of sending a greatly reduced electrical signal to the device's detecting element in the event that the capillary space is incompletely filled with test fluid. This reduced signal can be manipulated to produce an error signal which affirmatively apprises the device's user that such incomplete filling has occurred.