(19)

(11)

EP 0 720 744 A1

(12)

(43) Date of publication: 10.07.1996 Bulletin 1996/28 (21) Application number: 94928604.0 (22) Date of filing: 16.09.1994

(51) International Patent Classification (IPC):  G01N 33/ 53( . ) G01N 33/ 94( . ) G01N 33/ 543( . ) G01N 37/ 00( . ) (86) International application number: PCT/US1994/010473 (87) International publication number: WO 1995/008117 (23.03.1995 Gazette 1995/13)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 17.09.1993 US 19930123077 (71) Applicant: Guirguis, Raouf A. Rockville, MD 20852 (US)	(72) Inventor: Guirguis, Raouf A. Rockville, MD 20852 (US) (74) Representative: Hillier, Peter, et al  Reginald W. Barker & Co., Chancery House, 53-64, Chancery Lane London, WC2A 1QU London, WC2A 1QU (GB)