(19)

(11)

EP 0 302 054 A1

(12)

(43) Date of publication: 08.02.1989 Bulletin 1989/06 (21) Application number: 86905896.0 (22) Date of filing: 03.10.1986

(51) International Patent Classification (IPC):  G01N 1/ 06( . ) G01N 1/ 42( . ) (86) International application number: PCT/GB1986/000595 (87) International publication number: WO 1987/002130 (09.04.1987 Gazette 1987/08)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 04.10.1985 GB 19850024530 (71) Applicants: JACKSON, Brian Laurence Cambridge CB4 5AR (GB) PARKER, Philip Wilburton, Cambridge (GB)	(72) Inventors: JACKSON, Brian Laurence Cambridge CB4 5AR (GB) PARKER, Philip Wilburton, Cambridge (GB) (74) Representative: NANCARROW, Peter Holt (GB)  1 Oakington Road Girton GB-Cambridge CB3 0QH GB-Cambridge CB3 0QH (GB)