Chemistry strip reader and method

A chemistry strip reader for analyzing chemistry strips, comprising:

• a conveyor having a surface for supporting a plurality of chemistry strips in a plurality of imaging positions and for moving the chemistry strips through the imaging positions at discrete points in time;
• a camera for capturing images of a field of view that includes the plurality of imaging positions and any of the chemistry strips therein, wherein the images are captured at the discrete points in time;
• and
• a processor for determining reflectance values for each of the chemistry strips from the captured images at the discrete points in time;
• wherein for each of the chemistry strips, the processor is further configured to calculate a concentration determination associated therewith by:
• fitting the determined reflectance values for the chemistry strip to a curve defined by A exp[−B(t+to)]+C, where A, B, C, and to are fit parameters;
• determining a first slope of the curve for t=−to;
• comparing the first slope with known first slopes for given analyte concentrations;
• determining an asymptotic value of the curve;
• and
• comparing the asymptotic value with known asymptotic values for known analyte concentrations.

A method of analyzing a chemistry strip comprising:

• capturing a plurality of images of a chemistry strip at discrete points in time using a camera;
• determining reflectance values for the chemistry strip from the captured images using a processor;
• fitting the determined reflectance values for the chemistry strip to a curve defined by A exp[−B(t+to)]+C, where A, B, C, and to are fit parameters, using the processor;
• and
• calculating a concentration determination associated with the chemistry strip using the processor by:
• determining a first slope of the curve for t=−to, and
• comparing the first slope with known first slopes for given analyte concentrations.

A method of analyzing a chemistry strip comprising:

• placing a chemistry strip on a support surface of a conveyor;
• moving the conveyor surface to sequentially move the chemistry strip to a plurality of imaging positions at discrete times;
• capturing an image of the chemistry strip at each of the imaging positions using a camera;
• determining reflectance values for the chemistry strip from the captured images using a processor;
• fitting the determined reflectance values for the chemistry strip to a curve defined by A exp[−B(t+to)]+C, where A, B, C, and to are fit parameters, using the processor;
• and
• calculating a concentration determination associated with the chemistry strip using the processor by:
• determining a first slope of the curve for t=−to, and
• comparing the first slope with known first slopes for given analyte concentrations.