(19)

(11)

EP 0 594 673 A1

(12)

(43) Date of publication: 04.05.1994 Bulletin 1994/18 (21) Application number: 92914399.0 (22) Date of filing: 08.07.1992

(51) International Patent Classification (IPC):  B01D 57/ 02( . ) G01N 27/ 447( . ) (86) International application number: PCT/GB1992/001238 (87) International publication number: WO 1993/000986 (21.01.1993 Gazette 1993/03)

(84) Designated Contracting States: DE FR GB NL SE (30) Priority: 12.07.1991 GB 19910015073 (71) Applicant: Astromed Limited Cambridge CB4 4GS (GB)	(72) Inventors: MACKAY, Craig, Douglas Cambridge CB4 1BP (GB) BARKER, Richard, Frederick Cambridge CB3 8SG (GB) (74) Representative: Matthews, Heather Clare, et al  Keith W Nash & Co Pearl Assurance House 90-92 Regent Street Cambridge CB2 1DP Cambridge CB2 1DP (GB)