1. School of Chemistry, University of Glasgow, Joseph Black Building, University Avenue, G12 8QQ Glasgow, U.K.
2. MRC-University of Glasgow Centre for Virus Research, 464 Bearsden Road, G61 1QH Glasgow, U.K.
3. HORIBA France SAS, 14, Boulevard Thomas Gobert-Passage Jobin Yvon, CS 45002, 91120 Palaiseau, France
4. James Watt School of Engineering, University of Glasgow, Rankine Building, Oakfield Avenue, G12 8LT Glasgow, U.K.