Light-Triggered Release of Bioactive Molecules from DNA Nanostructures

Abstract

Recent innovations in DNA nanofabrication allow the creation of intricately shaped nanostructures ideally suited for many biological applications. To advance the use of DNA nanotechnology for the controlled release of bioactive molecules, we report a general strategy that uses light to liberate encapsulated cargoes from DNA nanostructures with high spatiotemporal precision. Through the incorporation of a custom, photolabile cross-linker, we encapsulated cargoes ranging in size from small molecules to full-sized proteins within DNA nanocages and then released such cargoes upon brief exposure to light. This novel molecular uncaging technique offers a general approach for precisely releasing a large variety of bioactive molecules, allowing investigation into their mechanism of action, or finely tuned delivery with high temporal precision for broad biomedical and materials applications.

Smart Nanostructures for Cargo Delivery: Uncaging and Activating by Light

“…Here, exposure to light irradiation induced cleavage of the linker and uncaging, allowing diffusion of the cargo molecules away from the protective cavity (Figure 2a). 46 In a novel strategy, Fan et al used X-ray radiation, which penetrates extremely well through living tissue, to achieve an on-demand/dose-controlled release from upconversion NPs (UCNPs, see below), i.e., poly-ethylene glycol (PEG)-modified NO-releasing theranostic UCNPs based on S -nitrosothiol-grafted mesoporous silica (MSN). Besides simultaneous upconversion luminescent-based imaging, exposure to X-ray irradiation caused cleavage of S–N bonds of S -nitrosothiol and hence release of the nitric oxide (NO).…”

DNA-Based Enzyme Reactors and Systems

“…Kohman et al [61] introduced a method to encapsulate bioactive molecules such as streptavidin and bovine serum albumin (BSA) within DNA nanostructures and release them using short (<60 s) pulses of light (Figure 5d). The strategy involved organic photolabile linker, which was reacted with cargo molecules and subsequently conjugated to oligonucleotides, allowing the cargo to be incorporated into a preassembled DNA origami cage (41 × 30 × 21 nm 3 in size) through 14 addressable ssDNA extensions in its cavity.…”

“…The closed box efficiently protects the assembled enzyme cascade pair from protease digestion [59]; ( c ) A DNA origami-based nanocarrier loaded with luciferase (LUC) enzymes. The enzyme activity can be tuned by coating the carrier with cationic polymers [60]; ( d ) A light-triggered release of proteins such as bovine serum albumin (BSA) from DNA origami container [61]; ( e ) A DNA cage that can trap and release an enzyme (HRP) through the temperature-controlled conformational changes [62]; ( f ) β-galactosidase (β-gal) can be coated by DNA strands for significantly enhanced cellular delivery [63]. A box with a lid in ( a ) is reproduced with permission from [56].…”

“…Copyright The Royal Society of Chemistry, 2016. ( d ) is reproduced with permission from [61]. Copyright American Chemical Society, 2016.…”

Light‐Patterned RNA Interference of 3D‐Cultured Human Embryonic Stem Cells

“…[18][19][20][21][22] However, these approaches rely largely on the visible light excitation sources and the construction of complex protein fusions via viral transfection. Other alternatives use photocaged small molecules and biopolymers for light-dependent gene regulation, [4,15,[23][24][25][26] which are limited by cellular delivery hurdles and the use of low tissue-penetrating UV-vis light. [15][16][17] We have developed a novel pulsed near-infrared (NIR) light based technique for the spatiotemporal control of gene silencing in 3D-cultured human embryonic stem cells (hESCs) by RNA interference.…”