Abstract: A method of determining the concentration of a preselected analyte species present in a sample fluid is disclosed, which method comprises: (a) providing an external computational means, a reference electrode and at least one substantially dry-stored sensor capable of exhibiting a response to changes in the concentration of a preselected analyte species before the sensor attains full equilibrated wet-up; (b) establishing electrical contact between the sensor, reference electrode and external computational means; (c) contacting the sensor and reference electrode with a calibrant fluid; (d) performing a first signal measurement in a first time window in the presence of the calibrant fluid; (e) displacing the calibrant fluid after performing the first signal measurement; (f) contacting the sensor and reference electrode with a sample fluid; (g) performing a second signal measurement in a second time window in the presence of the sample fluid; and (h) relating the first and second signal measurements to determine

Abstract: A system comprising a disposable device and hand held reader can perform a variety of electrochemical measurements on blood or other fluids. In operation, a fluid sample is drawn into the disposable device through an orifice by capillary action. The orifice is sealed off and the disposable device is inserted into the reader. The reader which controls the test sequence and flow of fluid causes a calibrant pouch located inside the device to be pierced, releasing the calibrant fluid to flow across the sensor arrays to perform calibration. Next an air bladder located in the device is depressed, forcing the sample across the sensors where measurements are performed and read by the reader which performs the calibrations. Once the measurements are made, the device can be withdrawn from the reader and discarded.

Abstract: A plurality of uniform microfabricated sensing devices are produced by establishing a plurality of base sensors on a substrate wafer, forming over at least a portion of each base sensor a permselective layer, superimposing a photoformable proteinaceous photoresist layer over a substantial portion of the permselective layer, and forming a topmost layer of an immobilized ligand receptor. The ligand receptor and corresponding ligand may be immunoreactive species.

Abstract: A fluidics head to facilitate the automatic testing of chemical and ionic sensing electronic circuit devices is provided. The fluidics head comprises a fluid confining cell having an open orifice capable of containing a known test fluid while the orifice is in leakproof engagement with sensing electronic circuit devices, an inlet and outlet opening capable of filling and discharging test fluids, and electrical probes capable of contacting the sensing electronic circuit devices so as to test the electrical response of the devices with the test fluids.

Abstract: A method and apparatus for automatically testing chemical and ionic sensing electronic circuits is provided. A fluid used in testing is placed in a hollow pipette with at least one open end. The open end of the pipette is applied directly against a sensing layer on the sensing electronic circuit forming a leakproof seal. Alternatively, a flow-through type fluid container is used and is advantageously applied with gas measurements. Test electronics are provided to compile and analyze the performance of various sensing layers. Aligning means automatically select a sensing electronic circuit and position the circuit such that the holding device can be urged against the sensing layer automatically.