Patent · US Expired

Biosensing instrument and method

US5243516A · kind A · utility

211Cited by
1References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 15, 1989
Grant dateSep 7, 1993
Priority date
Expiry dateDec 15, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N27/3273
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A biosensing system is described which determines whether a measured current is varying in accordance with a predetermined Cottrell current relationship. The system includes a test cell with at least a pair of electrodes which extend into a reaction zone, which reaction zone includes analyte reactants. An analog signal detector, in combination with a microprocessor, take plurality of current measurements between the electrodes over a plurality of succeeding measurement times, after a sample is placed in contact with the analyte reactants in the reaction zone. The microprocessor also stores a plurality of succeeding cpmparison constants which are derived by taking the inverse ratio of the square root of a measurement time divided by the square root of a subsequent measurement time. The microprocessor selects a pair of succeeding measurement times; derives a ratio of the currents measured at those times; and then compares the ratio of those currents with the comparison constant previously derived for the pair of succeeding measurement times. If the comparison indicates that the measured current ratio is dissimilar from the comparison constant, an indication is developed that the curr…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.