Microdroplet dispensing for a medical diagnostic device
AssigneeLifeScan, Inc.
InventorsIan A. Harding, Robert Justice Shartle, Glenn Renowitzky, Lewis Leung
Life of this patent
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Abstract
A medical diagnostic device has a non-absorbent substrate that has a hydrophilic target area on which a reagent is deposited by non-impact printing of microdroplets. During deposition, the device is moved relative to the stream of microdroplets to form a substantially uniform reagent layer on the substrate. The device is particularly well adapted for measuring blood coagulation times. In a preferred embodiment, coagulation times are determined by monitoring the optical transmission of light through the target area as an applied blood sample interacts with the reagent.
Claims11
A diagnostic reagent device for measuring an analyte concentration or characteristic of a biological fluid, including a non-absorbent substrate comprising:
- a) a sample application area for accepting a sample of the biological fluid for analysis;
- and
- b) a predetermined hydrophilic surface area for receiving, by nonimpact printing, a pulsed stream of microdroplets of a diagnostic reagent liquid comprising thromboplastin that interacts with the sample to cause in the sample a physically-measurable change that can be related to the analyte concentration or characteristic of the fluid.
A method for preparing a medical diagnostic reagent device, comprising the steps of
- (a) providing a non-absorbent substrate having at least one hydrophilic target surface area,
- (b) providing from a nonimpact print head onto a point within the hydrophilic surface area a pulsed stream of microdroplets of a diagnostic reagent liquid, in which the reagent liquid comprises thromboplastin,
- (c) moving the substrate relative to the steam, and
- (d) repeating steps b) and c) at least enough times to provide a substantially uniform layer of the liquid over the hydrophilic surface area.
Dependencies are inferred from the claim text.