(19)

(11)

EP 0 227 739 A1

(12)

(43) Date of publication: 08.07.1987 Bulletin 1987/28 (21) Application number: 86903858.0 (22) Date of filing: 19.05.1986

(51) International Patent Classification (IPC):  G01N 21/ 64( . ) G01N 22/ 00( . ) G01N 21/ 21( . ) (86) International application number: PCT/US1986/001096 (87) International publication number: WO 1986/007148 (04.12.1986 Gazette 1986/26)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 20.05.1985 US 19850736434 (71) Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA Berkeley, California 94720 (US)	(72) Inventors: MAESTRE, Marcos, Francisco Berkeley, CA 94703 (US) TINOCO, Ignacio, Jr. Berkeley, CA 94707 (US) (74) Representative: Horton, Andrew Robert Grant  BOWLES HORTON Felden House Dower Mews High Street Berkhamsted Hertfordshire HP4 2BL Berkhamsted Hertfordshire HP4 2BL (GB)