1. CasE13a http://2017.igem.org/Team:TUDelft
Schematic of the development of antibiotic resistance and how it can spread to humans

2. Schematic of the project
The project consists of three parts: a recently characterized variant of the CRISPR/Cas system (Cas13a) for fast and accurate detection; tardigrade proteins that increase the shelf-life of our device; and the coacervation method for visible read-out.

3. Overview of all the different aspects of our project.

5. CascAID

6. Recombinase Polymerase Amplification (RPA), as an isothermal alternative to PCR, is conducted at 37°C without the need for thermocycling and therefore reduces the requirements and costs of the accompanying hardware significantly. Since Cas13a targets RNA rather than DNA, we coupled RPA to in vitro transcription (TX). Since both reactions take place at the same temperature of 37°C, this can be done in a one-pot reaction. To render the RPA-TX distributable, we lyophilized the enzymes on filter paper, which, when sealed in a tight container, stabilizes the assay for storage.

7. Sample Processing Unit Paper Strip Reaction Unit Detector Unit
Sample Processing Unit
Paper Strip Reaction Unit
Detector Unit
CascAID combines an automated microfluidic device for rapid lysis and extraction of nucleic acids with a paper-based readout system.
Sample processing
We chose to combine heat lysis and isothermal amplification (RPA) to extract our target RNA from patient samples.
Readout circuit
We chose Cas13a for pathogen identification because of its specificity for nucleic acid sequence detection.
Detector
We chose a disposable paper strip combined with a reusable fluorescence detector to analyse our samples.