̽»¨ÏµÁÐ Technology

̽»¨ÏµÁÐ technology patented donor-acceptor systems which leverages years of innovation and developed in Preece and Robinson group in University of Birmingham. To date ̽»¨ÏµÁÐ have synthesised ~100 compounds which has allowed us to obtain a detailed understanding of the molecular factors which control:

Absorption

̽»¨ÏµÁÐ technology allows chemically modify donor molecular structure in order to tune the absorbance for specific properties.

High absorption extinction coefficients – ~100 000 M-1 cm-1 and lmax, ~30 000 M-1 cm-1 @ 355 nm

Absorbance spectrums of two donor cores used in ̽»¨ÏµÁÐ molecules for 355 nm (CTUV) and 405 nm (CTV) laser excitations.

Due to large aromatic area, ̽»¨ÏµÁÐ materials are suitable for multi-photon absorption experiments. To read more about this, go to Multiphoton Microscopy section.

Emission

̽»¨ÏµÁÐ technology based on donor-acceptor system is very chemically flexible allows to incorporate different groups onto the molecular systems. Thus, to date ̽»¨ÏµÁÐ have over 100 different compounds with emission covering the whole visible spectrum from blue to red (with further development on-going to move redder).

Figure shows emission of TpOx-Bu (Violet), TpOx-Ph-p-OMe (Blue), TpOx-2-Nap (Green) and TpOx-Ph-p-CN (Orange).
Brightness

̽»¨ÏµÁÐ fluorescent materials have high fluorescence Quantum Yield (30-70%).

Coupled with a high molar absorptivity of ≈ 100000 which resulting in bright emission. This high brightness leads to a high sensitivity allowing for the detection of small quantities of fluorophore ≈ 10-9 M

At 10 nanomolar solutions of fluorescent dyes are colourless under ambient light, but emit brightly under UV light.
Stability

̽»¨ÏµÁÐ fluorescent materials have exceptional stability in solution for long periods of time.

Averaged stability of 15 ̽»¨ÏµÁÐ fluorescent materials in THF solvent.
Solubility

̽»¨ÏµÁÐ fluorescent materials have good solubility in a range of organic solvents.

̽»¨ÏµÁÐ fluorescent materials can be dispersed in aqueous solvents and aqueous buffers via pre-dissolution in organic solvent such as DMSO.

̽»¨ÏµÁÐ fluorescent materials are soluble in: Chloroform, Tetrahydrofuran (THF), Dichloromethane (DCM), Toluene, Cyclohexanone, Cyclohexane, Di-ethyl ether, Ethyl Acetate, Acetone.

Thermal Stability

̽»¨ÏµÁÐ fluorescent materials show exception molecular stability in solid with most dyes having >250oC thermal stability.

TGA measurement of TpOx-Bu (Violet), TpOx-Ph (Blue), TpOx-2-Nap (Green), TpOx-1-Nap (Yellow) and TpOx-2-An (Orange).
Processability

̽»¨ÏµÁÐ fluorescent materials have good processability into polymer matrices via spin coating, melting and 3D printing, whilst maintaining fluorescence.

3D printed resin with ̽»¨ÏµÁÐ fluorescent material.
Fabricated PMMA films with ̽»¨ÏµÁÐ fluorescent material (TpOx-Ph) are colourless under ambient light, but emit brightly under UV light.
Reactive and Functional groups

̽»¨ÏµÁÐ technology based on donor-acceptor system is very chemically flexible allows to incorporate different groups onto the molecular systems. Currently, ̽»¨ÏµÁÐ can incorporate reactive functional groups such as -CO2H, -N3, -NH2, -active esters, -SH, -alkenes, -Br.

Furthermore, ̽»¨ÏµÁÐ technology is versatile platform to create new fluorescent probes for analyte sensing application.

̽»¨ÏµÁÐ fluorophores:

  • Undergo fluorescence quenching in the presence of electron deficient aromatics
  • Undergo fluorescent modulation upon binding metal cations in an appended crown ether moiety
  • Undergo fluorescence shifts upon modulation of the subphase pH

Fluorescence shifts upon modulation of the subphase pH.
Fluorescence shifts upon modulation of the subphase OH.
Fluorescent modulation upon binding metal cations in an appended crown ether moiety.
Fluorescence quenching in the presence of electron deficient aromatics.
Discotic Liquid Crystalline Properties

̽»¨ÏµÁÐ materials display Hexagonal Columnar Discotic Liquid Crystal (DLC) mesophases – a state of matter intermediate between liquid and solid. This mesophase gives rise to an anisotropy in photophysical properties such as light polarisation, light emission and charge transport. In addition, ̽»¨ÏµÁÐ materials are able to form nanoparticles and nanowires.

Polarising Light Microscope Image of ̽»¨ÏµÁÐ material showing texture typical for a texture which is indicative of the hexagonal columnar mesophase reported by XRD.
Schematic representation of discotic molecule arrangement in Hexagonal Columnar Discotic Liquid Crystal mesophase.

In addition, ̽»¨ÏµÁÐ materials are able to form nanoparticles and nanowires.

Fluorescence microscope picture of self-assembled nanowires using TpOx-Ph ̽»¨ÏµÁÐ material.
Photoconductors

Triphenoxazoles are organic insulators with charge mobility around ~ 10-3 cm2/Vs. When irradiated with UV light, ̽»¨ÏµÁÐ materials become photoconductors. The photocurrent display up to 2 orders of magnitude increase compared to the hexakis(alkyloxy)triphenylenes (TpH), which is the archetypical photoconductor.

Photocurrent ON and OFF switching with 350 nm UV light of TpH, TpOx-Ph and TpOx-2-Nap.