Ensuring adequate water quality is essential for human health and for effective allocation of resources in agriculture, energy, and manufacturing. However, the current state-of-the-art for water quality testing requires expensive equipment and technical expertise to analyze samples and takes days to obtain results from off-site labs, making it inaccessible to the public. Synthetic biology offers a promising solution to tackle this challenge. By harnessing mechanisms that natural systems use to sense and respond to changing surroundings, we can build biosensors that generate a visible signal upon detection of a contaminant. In particular, “cell-free” biosensors take these sense-and-respond functions out of live cells and put them in an open environment that is safe and cheap to deploy outside of a laboratory. In this dissertation, I discuss the development of fast, easy-to-use, field-friendly cell-free biosensors for detecting chemical contaminants in aqueous samples. In particular, the dissertation focuses on a novel biosensing platform called ROSALIND that can monitor a range of important water contaminants such as antibiotics, pharmaceutical and personal care products, and heavy metals. The platform harnesses natural sensors found in microbes and re-configures them into a test tube. When a sensor detects a contaminant, it produces a fluorescent RNA signal that can be visualized with a cheap, 3D-printable handheld device. ROSALIND can be freeze-dried for broad use by consumers outside of a laboratory. Finally, ROSALIND can be interfaced with a DNA nanotechnology called toehold-mediated strand displacement to enable molecular computing. ROSALIND interfaced with toehold-mediated strand displacement circuits significantly shorten the time to detection, can quantify a contaminant of interest, and enable sensing of multiple contaminants through logic computation. The study discussed in this dissertation demonstrates the power and feasibility of bringing cutting-edge biosensing technologies into the hands of people who need them the most.

Creator

• Jung, Jaeyoung Kirsten

DOI

• https://doi.org/10.21985/n2-6b8q-tt82

Subject

• Bioengineering
• Molecular biology

Language

• en

Alternate Identifier

• http://dissertations.umi.com/northwestern:15989
• etdadmin_upload_893092

Keyword

• Synthetic Biology
• Nucleic Acid Circuit
• In Vitro Transcription
• Biosensor
• Transcription Factor
• RNA

Date created

• 2022-01-01

Resource type

• Dissertation

Rights statement

• In Copyright