Diffractive Optics Sensors

Figure 1.  Two types of sensors: (A) Sensor prisms currently available for assay development; (B) Sensor disks featuring multiple sensors per disk.

Our current sensor technology is based upon the polystyrene prism, a disposable sensor that consists of a contiguous array of interaction surfaces or spots lining the bottom of a 10 µL flow channel (Figure 1A). The spots are composed of a coupling reagent pre-patterned in a repetitive sequence of lines forming a diffraction grating. Several attachment chemistries (eg: avidin, amine reactive, oligonucleotide-based addressing reagents for multiplexing) allow the user flexibility in coupling their own content to the sensors.

The sensor prisms are designed for use in the current dotLab® mX System. This system uses an automated sampling and high-precision fluidic controller to introduce samples and assay reagents onto the sensor. The diffractive optics detection unit of the dotLab® mX System continuously interrogates the sensor’s diffraction grating from below to create the diffraction signal without interference from the sample matrix. As molecules bind to the sensor surface, the real time signal responds in proportion to molecular size and concentration.

The upcoming sensor disks will feature multiple sensors on single disk (Figure 1B) thereby enabling higher sample throughput on our next generation diffractive optics instrument. These sensors will also allow for the incorporation of all reagents directly on the disk thereby improving workflow and reducing the overall assay time. The disk-based design of the sensor also permits a variety of assay formats, including higher multiplex capabilities and improved quantitation methods. For more information Axela’s future diffractive optics sensor, please contact us directly.

Available attachment chemistries

Several attachment chemistries (eg: avidin, amine reactive, oligonucleotide-based addressing reagents for multiplexing) are available for each sensor:

dot® - Avidin Sensor dot® - Covalent Sensor panelPlus™ Axela Custom Sensors
Surface Chemistry

Pre-patterned with avidin for biotinylated capture reagents

Carboxylic acid surface for covalently coupling protein amino groups using carbodiimide chemistry

Oligonucleotide linkers designed to hybridize complementary oligonucleotide labels attached to the capture reagents (more info)

Customized sensors created by Axela in collaboration with our scientists and manufacturing group

Features

Compatible with dotReady™ reagents or choose from thousands of readily available commercial biotinylated reagents

Easy conversion of plate based avidin or streptavidin immunoassays

An alternative when commercial biotinylated reagents are not available, or when quantities of protein samples are insufficient for offline conjugation

Allows for possible sample recovery for further offline analysis (eg. mass spectrometry)

Enables the custom creation of multiplex panels of up to 12 biomarkers, using one of Axela’s panelPlus Labeling Kits

No cross-talk between oligonucleotides

The sensors can be re-used by regenerating the surface using specialized regeneration buffers after each assay

Up to 32 biomarker multiplex panels per sensor

Pre-filled reagents built-into each sensor

Rapid assay times (<10minutes)

Sensor Type

Prisms and Disks

Prisms

Prisms (1-3 plex)

Disks (1-12 plex)

Disks