Method of identifying analytes
First Claim
1. A method of identifying an analyte using a chemical sensor which is arranged to produce an oscillatory output signal and which responds selectively to different analytes by a characteristic change in the frequency of the output signal, comprising the steps of:
- exposing the sensor to step changes in concentration of the analyte corresponding to an increase in the concentration of the analyte, and to a decrease in the concentration of the analyte;
measuring the sensor output frequency over a period following the respective step changes to provide frequency-time characteristics;
deriving expressions for the characteristics comprising a combination of exponential functions having characteristic parameters which are together indicative of the identity of the analyte; and
comparing the characteristic parameters with reference parameters to identify the analyte.
6 Assignments
0 Petitions
Accused Products
Abstract
A method of identifying an analyte, using a chemical sensor (e.g., a piezoelectric crystal oscillator) which produces an output frequency responsive to different analytes by a characteristic change in the output frequency. The sensor is exposed to a step change (to) in concentration of the analyte and the resulting frequency characteristic measured. An expression for this characteristic is derived consisting of two exponential functions (F, S), one (F) derived from the early part of the frequency characteristic and the other (S) from the latter part. The four parameters (A2, A3, A4, A5) resulting from the functions so obtained are characteristic of the particular analyte.
12 Citations
9 Claims
-
1. A method of identifying an analyte using a chemical sensor which is arranged to produce an oscillatory output signal and which responds selectively to different analytes by a characteristic change in the frequency of the output signal, comprising the steps of:
- exposing the sensor to step changes in concentration of the analyte corresponding to an increase in the concentration of the analyte, and to a decrease in the concentration of the analyte;
measuring the sensor output frequency over a period following the respective step changes to provide frequency-time characteristics;
deriving expressions for the characteristics comprising a combination of exponential functions having characteristic parameters which are together indicative of the identity of the analyte; and
comparing the characteristic parameters with reference parameters to identify the analyte. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
- exposing the sensor to step changes in concentration of the analyte corresponding to an increase in the concentration of the analyte, and to a decrease in the concentration of the analyte;
Specification