1. |
- Andreasson, Joakim, 1973, et al.
(author)
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Molecules for security measures: From keypad locks to advanced communication protocols
- 2018
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In: Chemical Society Reviews. - : Royal Society of Chemistry (RSC). - 1460-4744 .- 0306-0012. ; 47:7, s. 2266-2279
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Research review (peer-reviewed)abstract
- The idea of using molecules in the context of information security has sparked the interest of researchers from many scientific disciplines. This is clearly manifested in the diversity of the molecular platforms and the analytical techniques used for this purpose, some of which we highlight in this Tutorial Review. Moreover, those molecular systems can be used to emulate a broad spectrum of security measures. For a long time, molecular keypad locks enjoyed a clear preference and the review starts off with a description of how these devices developed. In the last few years, however, the field has evolved into something larger. Examples include more complex authentication protocols (multi-factor authentication and one-time passwords), the recognition of erroneous procedures in data transmission (parity devices), as well as steganographic and cryptographic protection.
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2. |
- Andreasson, Joakim, 1973, et al.
(author)
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Molecules with a sense of logic: a progress report
- 2015
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In: Chemical Society Reviews. - 1460-4744 .- 0306-0012. ; 44:5, s. 1053-1069
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Research review (peer-reviewed)abstract
- In this tutorial review, the most recent developments in the field of molecular logic and information processing are discussed. Special emphasis is given to the report of progress in the concatenation of molecular logic devices and switches, the design of memory systems working according to the principles of sequential logic, the mimicking of transistors, and the research on photochromic platforms with an unprecedented degree of functional integration. Furthermore, a series of achievements that add up to the conceptual diversity of molecular logic is introduced, such as the realization of highly complex and logically reversible Toffoli and Fredkin gates by the action of DNAzymes or the use of a multifluorophoric platform as a viable approach towards keypad lock functions.
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3. |
- Bliman, David, et al.
(author)
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A Caged Ret Kinase Inhibitor and its Effect on Motoneuron Development in Zebrafish Embryos
- 2015
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In: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 5
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Journal article (peer-reviewed)abstract
- Proto-oncogene tyrosine-protein kinase receptor RET is implicated in the development and maintenance of neurons of the central and peripheral nervous systems. Attaching activity-compromising photocleavable groups (caging) to inhibitors could allow for external spatiotemporally controlled inhibition using light, potentially providing novel information on how these kinase receptors are involved in cellular processes. Here, caged RET inhibitors were obtained from 3-substituted pyrazolopyrimidine-based compounds by attaching photolabile groups to the exocyclic amino function. The most promising compound displayed excellent inhibitory effect in cell-free, as well as live-cell assays upon decaging. Furthermore, inhibition could be efficiently activated with light in vivo in zebrafish embryos and was shown to effect motoneuron development.
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4. |
- Bälter, Magnus, 1986, et al.
(author)
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Emission color tuning and white-light generation based on photochromic control of energy transfer reactions in polymer micelles
- 2016
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In: Chemical Science. - 2041-6539 .- 2041-6520. ; 7:9, s. 5867-5871
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Journal article (peer-reviewed)abstract
- We encapsulate a fluorescent donor molecule and a photochromic acceptor unit (photoswitch) in polymer micelles and show that the color of the emitted fluorescence is continuously changed from blue to yellow upon light-induced isomerization of the acceptor. Interestingly, white-light generation is achieved in between. With the photoswitch in the colorless form, intense blue emission from the donor is observed, while UV-induced isomerization to the colored form induces an energy transfer reaction that quenches the donor emission and sensitizes the yellow emission from the colored photoswitch. The process is reversed by exposure to visible light, triggering isomerization to the colorless form.
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5. |
- Bälter, Magnus, 1986, et al.
(author)
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Reversible Energy-Transfer Switching on a DNA Scaffold
- 2015
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In: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 1520-5126 .- 0002-7863. ; 137:7, s. 2444-2447
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Journal article (peer-reviewed)abstract
- We show that FRET between Pacific Blue (PB) and Alexa488 (A488) covalently attached to a DNAscaffold can be reversibly controlled by photochromicswitching of a spiropyran derivative. With the spiropyranin the closed spiro isomeric form, FRET occurs freelybetween PB and A488. UV-induced isomerization to theopen merocyanine form shuts down the FRET process byefficient quenching of the PB excited state. The process isreversed by exposure to visible light, triggering theisomerization to the spiro isomer.
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6. |
- Chen, H. R., et al.
(author)
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Conformational effects of UV light on DNA origami
- 2017
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In: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 1520-5126 .- 0002-7863. ; 139:4, s. 1380-1383
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Journal article (peer-reviewed)abstract
- The responses of DNA origami conformation to UV radiation of different wavelengths and doses are investigated. Short- and medium-wavelength UV light can cause photo-lesions in DNA origami. At moderate doses, the lesions do not cause any visible defects in the origami, nor do they significantly affect the hybridization capability. Instead, they help relieve the internal stress in the origami structure and restore it to the designed conformation. At high doses, staple dissociation increases which causes structural disintegration. Long-wavelength UV does not show any effect on origami conformation by itself. We show that this UV range can be used in conjunction with photoactive molecules for photo-reconfiguration, while avoiding any damage to the DNA structures.
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7. |
- Chen, H. R., et al.
(author)
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Dynamic and Progressive Control of DNA Origami Conformation by Modulating DNA Helicity with Chemical Adducts
- 2016
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In: ACS Nano. - : American Chemical Society (ACS). - 1936-086X .- 1936-0851. ; 10:5, s. 4989-4996
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Journal article (peer-reviewed)abstract
- DNA origami has received enormous attention for its ability to program complex nanostructures with a few nanometer precision. Dynamic origami structures that change conformation in response to environmental cues or external signals hold great promises in sensing and actuation at the nanoscale. The reconfiguration mechanism of existing dynamic origami structures is mostly limited to single-stranded hinges and relies almost exclusively on DNA hybridization or strand displacement. Here, we show an alternative approach by demonstrating on-demand conformation changes with DNA-binding molecules, which intercalate between base pairs and unwind DNA double helices. The unwinding effect modulates the helicity mismatch in DNA origami, which significantly influences the internal stress and the global conformation of the origami structure. We demonstrate the switching of a polymerized origami nanoribbon between different twisting states and a well-constrained torsional deformation in a monomeric origami shaft. The structural transformation is shown to be reversible, and binding isotherms confirm the reconfiguration mechanism. This approach provides a rapid and reversible means to change DNA origami conformation, which can be used for dynamic and progressive control at the nanoscale.
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8. |
- Dreos, Ambra, 1987, et al.
(author)
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Three-Input Molecular Keypad Lock Based on a Norbornadiene-Quadricyclane Photoswitch
- 2018
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In: Journal of Physical Chemistry Letters. - : American Chemical Society (ACS). - 1948-7185. ; 9:21, s. 6174-6178
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Journal article (peer-reviewed)abstract
- Copyright © 2018 American Chemical Society. The photo- and acidochromic properties of a new generation norbornadiene derivative have been harnessed for the realization of a three-input keypad lock, where a specific sequence of inputs induces a unique output. Reversible quadricyclane/norbornadiene photoisomerization is reported, and this rare feature allows the first example of a norbornadiene-based molecular logic system. The function of this system is clearly rationalized in terms of the interconversion scheme and the absorption spectra of the involved species.
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9. |
- Ferreira, Ruben, 1982, et al.
(author)
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Design, Synthesis and Inhibitory Activity of Photoswitchable RET Kinase Inhibitors.
- 2015
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In: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 5
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Journal article (peer-reviewed)abstract
- REarranged during Transfection (RET) is a transmembrane receptor tyrosine kinase required for normal development and maintenance of neurons of the central and peripheral nervous systems. Deregulation of RET and hyperactivity of the RET kinase is intimately connected to several types of human cancers, most notably thyroid cancers, making it an attractive therapeutic target for small-molecule kinase inhibitors. Novel approaches, allowing external control of the activity of RET, would be key additions to the signal transduction toolbox. In this work, photoswitchable RET kinase inhibitors based on azo-functionalized pyrazolopyrimidines were developed, enabling photonic control of RET activity. The most promising compound displays excellent switching properties and stability with good inhibitory effect towards RET in cell-free as well as live-cell assays and a significant difference in inhibitory activity between its two photoisomeric forms. As the first reported photoswitchable small-molecule kinase inhibitor, we consider the herein presented effector to be a significant step forward in the development of tools for kinase signal transduction studies with spatiotemporal control over inhibitor concentration in situ.
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10. |
- Fleming, Cassandra, 1987, et al.
(author)
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A Fluorescent Kinase Inhibitor that Exhibits Diagnostic Changes in Emission upon Binding
- 2019
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In: Angewandte Chemie - International Edition. - : Wiley. - 1433-7851 .- 1521-3773. ; 58:42, s. 15000-15004
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Journal article (peer-reviewed)abstract
- The development of a fluorescent LCK inhibitor that exhibits favourable solvatochromic properties upon binding the kinase is described. Fluorescent properties were realised through the inclusion of a prodan-derived fluorophore into the pharmacophore of an ATP-competitive kinase inhibitor. Fluorescence titration experiments demonstrate the solvatochromic properties of the inhibitor, in which dramatic increase in emission intensity and hypsochromic shift in emission maxima are clearly observed upon binding LCK. Microscopy experiments in cellular contexts together with flow cytometry show that the fluorescence intensity of the inhibitor correlates with the LCK concentration. Furthermore, multiphoton microscopy experiments demonstrate both the rapid cellular uptake of the inhibitor and that the two-photon cross section of the inhibitor is amenable for excitation at 700 nm.
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