dotLab Sensors
Assay Spots
Core to the technology is the use of disposable polystyrene sensors each consisting of a contiguous array of interaction surfaces or spots lining the bottom of a 10 µL flow channel. The spots are composed of a coupling reagent pre-patterned in a repetitive sequence of lines forming a diffraction grating (Figure 2). 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.
Figure 2: A schematic representation of a dotLab sensor showing the contiguous arrangement of interaction spots lining the bottom of a flow channel. Pre-patterned coupling reagent on each spot forms a diffraction grating which is used to monitor molecular interactions in real-time.
The dotLab mX System introduces samples and assay reagents onto the sensor using an automated sampling system and high-precision fluidic controller. An integral prism allows continuous interrogation of the pattern 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 dot® - Covalent Sensor
The dot® - Covalent Sensor utilize a carboxylic acid surface that can be covalently coupled to protein amino groups using carbodiimide chemistry. In the linking procedure, the surface carboxyl groups first are activated and stabilized by reaction with EDC and sulfo-NHS. The activated groups subsequently react with the amines on the capture protein to form stable covalent amide linkages.
Features:
- Directly links capture species covalently, providing an excellent alternative when commercially biotinylated reagents are not available, or when quantities of protein samples are insufficient for offline conjugation
- Lidless sensor design makes sample recovery possible for further offline analysis (eg. mass spectrometry)
The dot® - Avidin Sensor
The dot® - Avidin Sensor is pre-patterned with avidin and utilizes the robust biotin-avidin interaction to rapidly immobilize biotinylated capture reagents.
Features:
- Low cost per test compared to traditional immunoassay techniques
- Requires only a few microliters of sample required for analysis
- Compatible with dotReady reagents or choose from thousands of readily available commercial biotinylated reagents
- Allows for easy conversion of plate based avidin or streptavidin immunoassays to the dotLab 's real time format