Contact Details

Email: M.Horbury@warwick.ac.uk

Telephone: +44(0)2476151013

Office: E0.11a

Lab: E0.19

Google Scholar

Biological systems have always had to contend with the ultraviolet radiation produced by the sun, which has led to a myriad of mechanisms to deal with any deleterious effects. While many intrinsic defence mechanisms exist within biomolecules, they are not perfect, therefore many biological systems employ molecules that preferentially absorb ultraviolet radiation, i.e. melanin pigments in human skin. However, yet again, this photoprotective mechanism has flaws, a delayed response, and in humans this can lead to sunburn or in severe cases, skin cancer. This had led to the use of artificial sunscreens to bolster the photoprotection of the human skin and avoid these dangerous side effects of sun exposure.

In recent years several synthetic molecules used within commercial sunscreen formula have come under scrutiny, with several being found to be phototoxic. This has led to the idea of exploring the photodynamics in other natural photoprotective biomolecules, like sinapate esters (a sub class of hydroxycinnamates), to potentially provide a new avenue towards making superior synthetic sunscreens.

To observe the photochemistry of these sunscreens, femtosecond resolution spectroscopy is required, therefore I use condensed-phase femtosecond transient electronic (UV/visible) absorption spectroscopy to do this. This technique has given unique insight into several synthetic sunscreen molecules, as well as several natural photoprotective molecules. My current work has focussed mainly on sinapate esters, the photoprotective molecules found in plant leaves.

Recently, building off the work on sinapate esters, I have been exploring the photochemistry of a series of synthetic molecules with the potential to be new sunscreening agents.

While there is a plethora of photoprotective mechanisms, both natural and synthetic, they can still fail, leading to, in the worst-case scenario, skin cancer. Therefore, I am interested in molecules that can be employed as photoactivated anti-cancer treatments; particularly ones that can be activated through two-photon excitation.

Selected Publication:

Elucidating nuclear motions in a plant sunscreen during photoisomerization through solvent viscosity effects

Michael D. Horbury, Wen-Dong Quan, Amandine L. Flourat, Florent Allais, and Vasilios G. Stavros, Phys. Chem. Chem. Phys., 2017, 19, 21127

Publication List:

Ultrafast photo-induced ligand solvolysis of cis-[Ru(bipyridine)₂(nicotinamide)₂]²⁺: experimental and theoretical insight into its photoactivation mechanism

Simon E. Greenough, Gareth M. Roberts, Nichola A. Smith, Michael D. Horbury, Russell G. McKinlay, Justyna M. Żurek, Martin J. Paterson, Peter J. Sadler, and Vasilios G. Stavros, Phys. Chem. Chem. Phys., 2014, 16, 19141

Solvent induced conformer specific photochemistry of guaiacol

Simon E. Greenough, Michael D. Horbury, James O. F. Thompson, Gareth M. Roberts, Tolga N. V. Karsili, Barbara Marchetti, Dave Townsend, and Vasilios G. Stavros, Phys. Chem. Chem. Phys., 2014, 16, 16187

Bridging the gap between the gas and solution phase: solvent specific photochemistry in 4-tert-butylcatechol

Michael D. Horbury, Lewis A. Baker, Wen-Dong Quan, Jamie D. Young, Michael Staniforth, Simon E. Greenough, and Vasilios G. Stavros, J. Phys. Chem. A., 2015, 119, 11989

Probing the ultrafast energy dissipation mechanism of the sunscreen oxybenzone after UVA irradiation

Michael D. Horbury, Lewis A. Baker, Simon E Greenough, Philip M Coulter, Tolga N. V. Karsili, Gareth M. Roberts, Andrew J. Orr-Ewing, Michael N. R. Ashfold, and Vasilios G. Stavros, J. Phys. Chem. Lett., 2015, 6, 1363

Broadband ultrafast photoprotection by oxybenzone across the UVB and UVC spectral regions

Lewis A. Baker, Michael D. Horbury, Simon E. Greenough, Michael N. R. Ashfold, and Vasilios G. Stavros, Photochem. Photobiol. Sci., 2015, 14, 1814

Ultrafast photoprotecting sunscreens in natural plants

Lewis A. Baker, Michael D. Horbury, Simon E. Greenough, Florent Allais, Patrick S. Walsh, Scott Habershon, and Vasilios G. Stavros, J. Phys. Chem. Lett., 2016, 7, 56

Ultrafast photoprotective properties of the sunscreening agent octocrylene

Lewis A. Baker, Michael D. Horbury, and Vasilios G. Stavros, Optics Express, 2016, 24, 10700

Photodynamics of potent antioxidants: ferulic and caffeic acids

Michael D. Horbury, Lewis A. Baker, Wen-Dong Quan, Simon E. Greenough, and Vasilios G. Stavros, Phys. Chem. Chem. Phys., 2016, 18, 17691

Excited-state dynamics of a two-photon-activatable ruthenium prodrug

Simon E. Greenough, Michael D. Horbury, Nichola A. Smith, Peter J. Sadler, Martin J. Paterson, and Vasilios G. Stavros, ChemPhysChem, 2016, 17, 221

Combatting AMR: photoactivatable ruthenium (ii)-isoniazid complex exhibits rapid selective antimycobacterial activity

Nichola A. Smith, Pingyu Zhang, Simon E. Greenough, Michael D. Horbury, Guy J. Clarkson, Daniel McFeely, Abraha Habtemariam, Luca Salassa, Vasilios G. Stavros, Christopher G. Dowson, and Peter J. Sadler, Chem. Sci., 2017, 8, 395

Photoisomerization of ethyl ferulate: A solution phase transient absorption study

Michael D. Horbury, Lewis A. Baker, Natércia D. N. Rodrigues, Wen-Dong Quan, and Vasilios G. Stavros, Chem. Phys. Lett., 2017, 673, 62

Observation of excited state absorption in the V-Cr Prussian blue analogue

Luke Hedley, Michael D. Horbury, Florian Liedy, and J. Olof Johansson, Chem. Phys. Lett., 2017, 687, 125

Controlled fabrication of osmium nanocrystals by electron, laser and microwave irradiation and characterisation by microfocus X-ray absorption spectroscopy

Anaïs Pitto-Barry, Kalotina Geraki, Michael D. Horbury, Vasilios G. Stavros, J. Frederick W. Mosselmans, Richard I. Walton, Peter J. Sadler and Nicolas P. E. Barry, Chem Comm, 2017, 53, 12898

Photophysics of the sunscreen ingredient menthyl anthranilate and its precursor methyl anthranilate: A bottom-up approach to photoprotection

Natércia D. N. Rodrigues, Neil C. Cole-Filipiak, Michael D. Horbury, Michael Staniforth, Tolga N. V. Karsili, Yoann Peperstraete, and Vasilios G. Stavros, J. Photochem. Photobiol. A, 2017, 353, 376

Investigating isomer specific photoprotection in a model plant sunscreen

Michael D. Horbury, Amandine L. Flourat, Simon E. Greenough, Florent Allais, and Vasilios Stavros, Chem. Comm., 2018, 54, 936

Spectroscopic studies on photoinduced reactions of the anticancer prodrug, trans,trans,trans-[Pt(N₃)₂(OH)₂(py)₂]

Robbin R. Vernooij, Tanmaya Joshi, Michael D. Horbury, Bim Graham, Ekaterina I. Izgorodina, Vasilios G. Stavros, Peter J.Sadler, Leone Spiccia, and Bayden R. Wood, Chem. Eur. J., 2018, 24, 1

Unravelling the photoprotection properties of mycosporine amino acid motifs

Jack M. Woolley, Michael Staniforth, Michael D. Horbury, Gareth W. Richings, Martin Wills and Vasilios G. Stavros, J. Phys. Chem. Letts., 2018, 9, 3043

Determination of Secondary Species in Solution through Pump-Selective Transient Absorption Spectroscopy and Explicit-Solvent TDDFT

Matthew A. P. Turner, Michael D. Horbury, Vasilios G. Stavros and Nicholas D. M. Hine, J. Phys. Chem. A, 2019, 123, 873

The Role of Symmetric Functionalisation on Photoisomerisation of a UV Commerical Chemical Filter

Jack M. Woolley, Jack S. Peters, Matthew A. P. Turner, Guy J. Clarkson, Michael D. Horbury and Vasilios G. Stavros, Phys. Chem. Chem. Phys., 2019, DOI: 10.1039/C8CP06536E