OPTICAL SENSOR
An optical reagent format with a precise capillary channel is made by molding a format on a carrier of a precise predetermined thickness. The carrier includes an insert at least a portion of which is molded in the format. Once the format is made, the insert is detached from the carrier and removed from the format leaving a precisely dimensioned capillary channel with an inlet and vent. A reagent may be applied in the capillary channel and the format used to measure the analyte in a fluid such as blood. An electrochemical sensor with a capillary channel is formed by placing a sacrificial insert and electrodes on a sensor base and applying plastic material. After the plastic material is cured, the sacrificial is removed leaving a capillary channel in the sensor. The inserts may be removed by a tool including a clamp for clamping and holding each insert stationary and a sliding block to which the sensor is secured.
1 . A method of making an optical reagent format with a capillary gap, comprising:
providing a carrier with an insert, said carrier and insert being of a predetermined thickness;
placing said carrier in a mold;
molding a format onto said carrier and insert;
separating said insert from said carrier; and
removing said insert from said format leaving a capillary gap in said format.
2 . The method of making an optical reagent format claimed in claim 1 further comprising applying reagent in said capillary gap.
3 . The method of making an optical reagent format claimed in claim 1 said capillary gap having open sides, and sealing said open sides of said capillary gap.
4 . The method of making an optical reagent format claimed in claim 1 further comprising removing said format from said carrier.
5 . The method of making an optical reagent format claimed in claim 1 providing a plurality of carriers joined together and each including an insert, and molding a format onto each of said plurality of carriers and inserts.
6 . The method of making an optical reagent format claimed in claim 1 said format including a pair of legs, further comprising forming said capillary gap between a pair of legs of said format.
7 . The method of making an optical reagent format claimed in claim 1 wherein molding said format comprises molding a first format on an upper surface of said carrier and molding a second format on a lower surface of said carrier.
8 . The method of making an optical reagent format claimed in claim 7 wherein said first and second formats are of a conical configuration.
9 . A method of making an optical reagent format with a capillary gap, comprising:
providing a carrier of a predetermined thickness;
providing an insert on said carrier;
molding a format onto said carrier and said insert with a portion of said insert extending out of said format; and
removing said insert from said format to provide a capillary channel with an inlet and a vent in said format formed by said insert.
10 . The method of making an optical reagent format claimed in claim 9 comprising removing said carrier from said format.
11 . The method of making an optical reagent format claimed in claim 9 said insert comprising a material of a melt temperature higher than the melt temperature of the material of said format.
12 . The method of making an optical reagent format claimed in claim 9 comprising molding said format with a first leg for the application of a light source and a second leg for the application of a light detector, said capillary channel being between said first and second legs.
13 . The method of making an optical reagent format claimed in claim 9 comprising molding said format with a first conical member on a first side of said format and a second conical member on a second side of said format with said capillary channel between said first conical member and said second conical member.
14 . A method of molding an electrochemical sensor using a sacrificial insert, comprising:
providing a first mold;
inserting a first electrical contact in said first mold;
inserting a second electrical contact in said first mold;
closing said first mold with a second mold;
injecting material for forming a sensor into said closed first and second molds;
curing said material; and
extracting said sacrificial insert from said sensor.
15 . The method of molding an electrochemical sensor claimed in claim 14 wherein extracting said sacrificial insert includes clamping said insert and moving said sensor relative to said insert.
16 . A tool for extracting a sacrificial insert from an electrochemical sensor, comprising:
a clamp for clamping a sacrificial insert in a stationary position;
a first block moveable relative to said clamp;
a drive member for moving said block relative to said clamp; and
an attachment member on said block to attach a sensor with a sacrificial insert onto said block.
17 . The tool claimed in claim 16 further comprising a base, said clamp including a second block secured to said base.
18 . A sensor, comprising:
a sensor body;
a first access window in said sensor body;
a second access window in said sensor body; and
an insert in said sensor body between said first access window and said second access window.
19 . An optical sensor adapted to assist in analyzing a liquid sample, the sensor comprising:
a sensor body;
a first access window formed in the sensor body;
a second access window formed in the sensor body; and
a sacrificial insert disposed in the sensor body extending between the first and second access windows;
wherein removal of the sacrificial insert forms a channel extending between the first and second access windows in the sensor body.
20 . The optical sensor of claim 19 wherein the sacrificial insert comprises metal.
21 . The optical sensor of claim 20 wherein the metal comprises stainless steel.
22 . The optical sensor of claim 19 wherein the first access window is adapted for source optics and the second access window is adapted for detection optics, the second access window being directly below the first access window.
23 . The optical sensor of claim 19 further including an access hole formed in the body, the access hole being adjacent to the first and second access windows, the access hole being adapted to assist in contacting the sacrificial insert.
24 . The optical sensor of claim 19 wherein the sacrificial insert comprises a material having a melt temperature higher than the melt temperature of the sensor body.
25 . The optical sensor of claim 19 wherein the sensor body further includes a reagent disposed within the channel.
26 . The optical sensor of claim 19 wherein the channel is a capillary channel.
27 . The optical sensor of claim 19 wherein the sensor body comprises a plastic material.