ACCESS™ Lab Cards

The T-Sensor^®Access™ Lab Card

The T-Sensor Access Lab Card is especially suited to chemistry and special chemistry analyses, including immunoassays. Use this standard format of the T-Sensor technology to demonstrate the quantitative detection of an analyte in a sample using a reference (control) solution.

Analyte Detection with the T-Sensor^® Platform

The T-Sensor platform enables detection of analytes in a variety of complex fluid samples, including whole blood, without prior separation. Most importantly, this structure enables novel calibration-free assay formats compatible with Point of Care (POC) diagnostics. Using the T-Sensor platform's multiple inlets can bring fluid streams together to flow in a central channel. This is shown in Figure A. A reference solution enters the device from the left, a detection solution enters in the middle, and a sample stream enters from the bottom right port. All streams flow adjacent to one another after merging at the T-junction of the central detection channel. The detection channel stream exits into the waste port shown at the top. Under microfluidic flow conditions (sometimes referred to as Low-Reynold's-Number-Flow), there is no mixing in the central channel. The only transport of material from one stream to another is by diffusion. Diffusion separates components of a sample based on molecular size and shape.

In the T-Sensor platform, indicator chemistries and optical technology may be used to identify and quantitate components in the central microfluidic channel. The instrumentation for performing this analysis is remarkably simple, amounting to little more than a white light and a digital camera.

Figure B illustrates an enlarged cross section of the T-Sensor detection area. The labels refer to the following details:

1. The original flow boundaries 2. Reference Stream 3. Particle-filled sample stream 4. Diffusion of detector substance into reference stream 5. Diffusion of reference analyte into the detection stream 6. Detection Stream 7. Diffusion of sample analyte into detection stream 8. Diffusion of detector substance into the sample stream 9. Detector cross-section used by imaging device

Ordering Information

T-Sensor^® Access™ Lab Cards are sold in lots of twenty each. No instrumentation is required. User instructions provided.

The H-Filter^® Access™ Lab Card

One of Micronics' fundamental technologies is the H-Filter^® platform, which enables the continuous separation of particles by size (e.g., the separation of blood cells from plasma, or DNA from salts). The name comes from the resemblance of the microfabricated fluidic channels to the letter H.

The principle of the H-Filter platform relies on the absence of turbulent mixing within a microfluidic channel. Two flow streams can be brought together and run side by side in the center channel of the H with laminar flow characteristics producing absolutely no turbulent mixing. Because there is no mixing, the only transport of molecules from one flow stream to the other is by diffusion.

Diffusion is the movement of particles from areas of high concentration to areas of lower concentration. Diffusion is a natural phenomenon, requiring no external source of energy. The major factors affecting the rate of diffusion are (a) the size and shape of the particles; (b) the viscosity of the solution; and (c) the temperature of the medium. In the figure displayed at left, small molecules will diffuse quickly from a sample stream to the buffer stream, while very large molecules and particles will remain indefinitely in the sample stream because of their much larger size and much decreased diffusion rate.

The H-Filter^® Access™ Lab Card has applications in the area of sample processing for analytical chemistry, rare reagent isolation and recovery, and as a stand-alone low cost separation device.

Ordering Information

H-Filter^® Access™ Lab Cards are sold in lots of twenty each. No instrumentation is required. User instructions provided.