Dr Patrick Mesquida
Telephone: +44 020 7848 2241
Office: S1.16, Strand Building, Strand Campus
Research Group: Experimental Biophysics and Nanotechnology
As a physicist with technical as well as with biophysical focus, I am fascinated by the prospect of miniaturisation and the integration of biological materials such as proteins or cells into technical systems. These goals cannot be achieved by conventional techniques alone and they require a multidisciplinary approach involving expertise from physics, engineering, chemistry and biology.
Things I am particularly interested in are:
The properties of supramolecular structures of polypeptides such as amyloid or collagen fibrils
Surface functionalisation and characterisation of solid substrates for biology
Biocompatible micro- and nanopatterning
Experimental techniques in which I have particular expertise:
Scanning-probe techniques (Atomic Force Microscopy, Electrical Force Microscopy and related methods)
Optical Microscopies (Fluorescence Microscopy, Differential Interference Contrast Microscopy, Confocal Microscopy)
Soft-lithography (Microcontactprinting, Micromolding in capillaries, etc.)
Surface preparation (Spin-coating, Chemical and Physical Vapour Deposition)
Differential Scanning Calorimetry
Circular Dichroism Spectroscopy
Biophysics, collagen, amyloid fibrils
Leung C., Kinns H., Hoogenboom B.W., Howorka S., Mesquida P., Imaging surface charges of individual biomolecules. NANO LETTERS 9 (7) (2009) pp2769-. We obtained high-resolution surface potential images of individual proteins and DNA. These results are a major step in a better understanding of the complex interactions of biomolecules, the ultimate basic building-blocks of all life forms.
Wenger M.P.E., Bozec L., Horton M.A., Mesquida P., Mechanical properties of collagen fibrils. BIOPHYSICAL JOURNAL, 93 (2007) pp1255-1263 (link). Collagen is the one of the most important proteins. Its fibrils are present in skin, bones, hair and connective tissue and keep the human body in shape. In this paper, the elastic modulus of individual collagen fibrils (a few hundred nanometers in diameter) is determined by AFM-nanoindentation.
Mesquida P., Riener C.K., MacPhee C.E., McKendry R.A., Morphology and mechanical stability of amyloid-like peptide fibrils, JOURNAL OF MATERIALS SCIENCE: MATERIALS IN MEDICINE, 18 (7) (2007) pp1325-1331.(link). Amyloid fibrils are the hallmark of degenerative diseases such as Alzheimer's or Parkinson's Disease. They mechanically disrupt the tissue of organs such as the brain or the liver. In this paper, we investigated the mechanical properties of such fibrils on the artificial model system TTR105-115.
Blanco, E.M., Horton, M.A., Mesquida, P., Simultaneous investigation of the influence of topography and charge on protein adsorption using artificial nanopatterns. LANGMUIR, 24 (6) (2008), 2284-2287. (available online) Avidin adsorption on polystyrene is increased by topographical nanopatterns but not by charge patterns.
Micro- and nanofabrication
Blanco E.M., Nesbitt S.A., Horton M.A., Mesquida P., A Multiprotein Microarray on Silicon Dioxide Fabricated by Using Electric-Droplet Lithography. ADVANCED MATERIALS Vol.19 (2007), 2469-2473 (available online
A fully functional microarray - just a few hundred micrometers in size - that can detect and identify different antibodies. It is based on a silicon chip to allow integration into state-of-the-art microelectronic circuits.
Mesquida P., Knapp H.F., Stemmer A., Charge writing on the nanometre scale in a fluorocarbon film, SURFACE AND INTERFACE ANALYSIS 33 (2): 159-162 FEB 2002. (link) How to write stable, electrical patterns into Teflon(TM)-like materials and read them out again. Could be good for alternative data storage methods. 1 electrical "bit" is as small as a virus.
Mesquida P., Stemmer A., Attaching Silica Nanoparticles from Suspension onto Surface Charge Patterns Generated by a Conductive Atomic Force Microscope Tip. ADVANCED MATERIALS 13 (18): 1395-1398 SEP 14 2001. (link) The Atomic Force Microscope is not only good for imaging small things but also for manipulating them. This article tells you how to arrange particles - as small as a virus - on a flat surface by first drawing an electrical pattern and then dipping the sample into the particle solution. A bit like xerography (photocopiers), just much more precise.