prior research funders
Thanks to the many organisations that have funded the MacKenzie lab’s research.
research themes
UPCONVERSION NANOPARTICLES: synthesis, design, functionalisation
Upconversion nanoparticles (UCNPs) are lanthanide-doped nano-crystals with incredibly useful capability of absorbing near-infrared red light (typically ~980 nm or 808 nm) and emitting visible photons (emission colour dependent on UCNP dopants). This results in no tissue autofluorescence, plus the UCNPs do not photobleach, and their emission can be time-gated to separate UCNP emission from dyes and biological fluorophores. An added bonus that the near-infrared excitation is “cell friendly” and can traverse several centimetres of tissue. This makes UCNPs very well suited to biological applications, especially imaging through tissue.
The surface of UCNPs can also be modified with shells, ligands, and polymers to enable functional molecular loading, e.g. attaching fluorescent dyes or sensor molecules. This makes UCNPs a uniquely advantageous nano-sensor platform which can infiltrate biological cells and tissues as sensors or as light delivery platforms for photodynamic therapy. UCNPs can also be used in transparent display technologies, high-temperature optical thermometry, solar cells, data storage, and invisible security inks.
We routinely produce the following types of UCNPs:
Oleic-acid coated UCNPs (dispersible in oils) (via autoclave or microwave reactors)
PEI -coated UCNPs with core-shell morphology and dual-waveband excitation (dispersible in water) [PEI = polyethyleneimine] (via autoclave or bench-top reactions)
PVP-coated UCNPs (dispersible in water and organic solvents) [PVP = polyvinylpyrrolidone] (via an open-to-air reaction)
We incorporate an array of sensitiser and emitter dopants to tune excitation and emission wavebands, including Yb(III), Nd(III), Gd(III), Er(III), Tm(III), and Mn(II) amongst others.
We are also interested in the development of superfluorescent/superradiant upconversion quantum materials, which exhibit quantum properties at room-temperature (possibly even at hotter temperatures). Such superfluorescent materials have exceptionally fast photon emission, which could lead to new quantum technologies with applications in imaging, sensing, and telecommunications.
Our cutting-edge Edinburgh Instruments FS5 V2 spectrometer is custom-configured for upconversion, featuring 808, 980, 1550 nm excitation lasers, upconversion lifetime measurement, upconversion quantum yield measurement (liquid and solid state), and temperature control.
[1] Rebecca McGonigle, Christian Homann, Ciera Connelly, Marta Gajewska, Niko Hildebrandt, Robert Pal, Ute Resch-Genger, Shiao Y Chow, Lewis Edward MacKenzie; Polyethyleneimine (PEI) molecular weight alters the photophysical and FRET properties of water dispersible NaYF4:Yb,Er upconversion nanoparticles. Nanoscale 2026; https://doi.org/10.1039/D6NR02308
MIRROR LIFE CONTINGENCY DETECTION/DIAGNOSTICS/ASSAY
Life on earth is based upon a single chirality set where DNA is predominately right handed and proteins are predominantly left handed. Mirror life - life of the opposite chirality to life on Earth - is a high-profile, yet currently speculative biohazard that could pose an existential risk to all life on Earth, and so biologists are calling for an international moratorium/ban on all mirror life development research. Hopefully we never have to deal with the hazards of mirror life, but should we ever encounter mirror life beyond Earth, or if mirror life is ever created by humans, then we will need a way of detecting mirror life. In collaboration with Prof. Robert Pal of Durham University, we have published the world’s first approach for a contingency assay against mirror life. This approach is based upon circularly polarised luminescence (CPL) generated by fluorescent and luminescent probes.
The contingency assay for mirror life is set out in Royal Society Open Science, October 2026 issue:
