Gene therapy and transgenic research have advanced quickly in recent years due to the development
of CRISPR technology. The rapid development of CRISPR technology has been largely
benefited by chemical engineering. Firstly, chemical or synthetic substance enables spatiotemporal
and conditional control of Cas9 or dCas9 activities. It prevents the leaky expression of CRISPR components,
as well as minimizes toxicity and off-target effects. Multi-input logic operations and complex
genetic circuits can also be implemented via multiplexed and orthogonal regulation of target genes.
Secondly, rational chemical modifications to the sgRNA enhance gene editing efficiency and specificity
by improving sgRNA stability and binding affinity to on-target genomic loci, and hence reducing
off-target mismatches and systemic immunogenicity. Chemically-modified Cas9 mRNA is also more
active and less immunogenic than the native mRNA. Thirdly, nonviral vehicles can circumvent the
challenges associated with viral packaging and production through the delivery of Cas9-sgRNA ribonucleoprotein
complex or large Cas9 expression plasmids. Multi-functional nanovectors enhance genome
editing in vivo by overcoming multiple physiological barriers, enabling ligand-targeted cellular
uptake, and blood-brain barrier crossing. Chemical engineering can also facilitate viral-based delivery
by improving vector internalization, allowing tissue-specific transgene expression, and preventing inactivation
of the viral vectors in vivo. This review aims to discuss how chemical engineering has
helped improve existing CRISPR applications and enable new technologies for biomedical research.
The usefulness, advantages, and molecular action for each chemical engineering approach are also
highlighted.
Digital logic gates in soft, conductive mechanical metamaterials