Photo-isomerization of azobenzene containing surfactants induced by near-infrared light using upconversion nanoparticles (UCNPs) as mediator.

07:00 EST 9th January 2019 | BioPortfolio

Summary of "Photo-isomerization of azobenzene containing surfactants induced by near-infrared light using upconversion nanoparticles (UCNPs) as mediator."

Here we report on photo-isomerization of azobenzene containing surfactants induced during irradiation with near-infrared (NIR) light in the presence of upconversion nanoparticles (UCNPs) acting as mediator. The surfactant molecule consists of charged head group and hydrophobic tail with azobenzene group incorporated in alkyl chain. The azobenzene group can be reversible photo-isomerized between two states: trans- and cis- by irradiation with light of appropriate wavelength. The trans-cis photo-isomerization is induced by UV light, while cis-trans isomerization proceeds either thermally in dark, or can be accelerated by exposing to illumination with longer wavelength typically in blue/green range. We present the application of lanthanide doped upconversion nanoparticles (UCNPs) to successfully switch azobenzene containing surfactants from cis to trans conformation in bulk solution using NIR light. Using Tm or Er as activator ions, the UCNPs provide emission in the spectral range of 450 nm < λ<sub>em</sub> < 480 nm (for Tm<sup>3+</sup>, three and four photon induced emission) or 525 nm < λ<sub>em</sub> < 545 nm (for Er<sup>3+</sup>, two photon induced emission), respectively. Especially for UCNPs containing Tm<sup>3+</sup> a good overlap of the emission with the absorption bands of the azobenzene is present. Under illumination of the surfactant solution with NIR light (λ<sub>ex</sub>= 976 nm) in the presence of the Tm<sup>3+</sup>-doped UCNPs, the relaxation time of cis-trans photo-isomerization was increased by almost 20-times compared to thermally induces isomerization. The influence of thermal heating due to the irradiation using NIR light was shown to be minor for solvents not absorbing in NIR spectral range (e.g., CHCl<sub>3</sub>) in contrast to water, which shows a distinct absorption in the NIR.


Journal Details

This article was published in the following journal.

Name: Journal of physics. Condensed matter : an Institute of Physics journal
ISSN: 1361-648X


DeepDyve research library

PubMed Articles [11435 Associated PubMed Articles listed on BioPortfolio]

Electrical detection of plasmon-induced isomerization in molecule-nanoparticle network devices.

We use a network of molecularly linked gold nanoparticles (NPSAN: nanoparticle self-assembled network) to demonstrate the electrical detection (conductance variation) of plasmon-induced isomerization ...

Rationally designed azobenzene photoswitches for efficient two-photon neuronal excitation.

Manipulation of neuronal activity using two-photon excitation of azobenzene photoswitches with near-infrared light has been recently demonstrated, but their practical use in neuronal tissue to photost...

Photoinduced reversible solid-to-liquid transitions using photoswitchable materials.

Heating and cooling can induce reversible solid-to-liquid transitions of matter. In contrast, athermal photochemical processes can induce reversible solid-to-liquid transitions of some newly developed...

Low-Threshold Reversible Electron-Induced and Selective Photoinduced Switching of Azobenzene Derivatives under Ambient Conditions.

Mono-carboxyl-functionalized azobenzene and arylazopyrazole have been employed for electron-induced and photoinduced switching under ambient conditions. The microscopic structure and the switching beh...

Direct Imaging of Photo-Switching Molecular Conformations Using Individual Metal Atom Markers.

Photo-switching behavior of individual organic molecules was imaged by annular dark-field scanning transmission electron microscopy (ADF-STEM) using a highly electron beam transparent graphene support...

Clinical Trials [3212 Associated Clinical Trials listed on BioPortfolio]

Traumatic Brain Injury in Veterans and Near-Infrared Phototherapy

This is a proof-of-concept study designed to demonstrate whether increases in cerebral blood flow, improvements in brain functioning, and reductions in symptomology associated with traumat...

Study of LED Phototherapy for Musculoligamentous Lesions

The purpose of this study is to determine whether LED phototherapy using combined red and near infrared light (approved: Ministry of Health of Russian Federation No. 29/06070997/1080-00, E...

Efficacy of Near Infrared Phototherapy in Type 2 Diabetic Neuropathy

This is a double blind, randomized, placebo-controlled study in which a total of 120 patients will be selected from a broad spectrum group of typical Americans (all demographics including ...

A Single-Center, Exploratory Study to Analyze the Dynamics of Skin Microflora Following Exposure to Surfactants

The purpose of this study is to understand the changes in skin microflora, skin barrier function, and skin biochemical constituents in response to direct contact with model surfactants use...

Epidemiology and Co-Reactivity of Novel Surfactant Allergens

The primary objectives of this study are to identify positivity rates to three novel surfactants (ingredients used in soaps, detergents, and other cleansers that serve to lower the surface...

Medical and Biotech [MESH] Definitions

Measurement of the regional temperature of the body or an organ by infrared sensing devices, based on self-emanating infrared radiation.

That portion of the electromagnetic spectrum usually sensed as heat. Infrared wavelengths are longer than those of visible light, extending into the microwave frequencies. They are used therapeutically as heat, and also to warm food in restaurants.

Spectrophotometry in the infrared region, usually for the purpose of chemical analysis through measurement of absorption spectra associated with rotational and vibrational energy levels of molecules. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

A noninvasive technique that uses the differential absorption properties of hemoglobin and myoglobin to evaluate tissue oxygenation and indirectly can measure regional hemodynamics and blood flow. Near-infrared light (NIR) can propagate through tissues and at particular wavelengths is differentially absorbed by oxygenated vs. deoxygenated forms of hemoglobin and myoglobin. Illumination of intact tissue with NIR allows qualitative assessment of changes in the tissue concentration of these molecules. The analysis is also used to determine body composition.

Abnormally high temperature intentionally induced in living things regionally or whole body. It is most often induced by radiation (heat waves, infra-red), ultrasound, or drugs.

Quick Search


DeepDyve research library

Searches Linking to this Article