Printer Friendly

...and toxic chemicals from the blood.

...and toxic chemicals from the blood

Biochemical engineers at the Massachusetts Institute of Technology is Cambridge have covalently bonded microscopic plastic beads to enzymes derived from microbes. In animal tests, blood filters containing the bead-bound enzymes efficiently and selectively broke down the chemicals against which they were targeted, reports Robert Langer, leader of the filtering systems' design team.

In tests with about 50 sheep, external blood filters containing the bacterial enzyme heparinase removed 99 percent of the anticoagulant drug heparin within about 15 minutes. In similar experiments using 20 rats with jaundice -- caused by a toxic buildup of bilirubin (a brain-damaging, yellow degradation product of hemoglobin) -- a bead-bound fungal enzyme harmlessly broke down all of the bilirubin in filtered blood.

Blood sampled from treated animals showed that 50 percent of the toxic compound -- heparin or bilirubin -- still circulated in the body, perhaps the result of a replenishing from stored residues in tissues. The enzyme filtering was sufficient, however, to reduce body concentrations to nontoxic levels, Langer notes. He anticipates that heparinase treatment, now under consideration for commercial development, may eventually be used in patients undergoing open-heart surgery. He adds that a similar, quick external filtering of blood from severely jaundiced newborns -- perhaps through the umbilicus -- may one day eliminate their need for potentially dangerous blood transfusions.
COPYRIGHT 1989 Science Service, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1989, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:Chemistry; report from the American Chemical Society's spring national meeting; microscopic plastic beads bonded to enzymes filter toxic chemicals from blood
Author:Amato, Ivan
Publication:Science News
Date:Apr 29, 1989
Words:216
Previous Article:New catalysts scavenge nitrogen oxides emissions....
Next Article:Neural networks predict reactions.
Topics:


Related Articles
Is air pollution worse indoors than out?
Embedded sentinels of toxicity; scientists are beginning to identify when, where and how certain toxic substances affect the body by studying...
Free radicals in liberal amounts.
Trapping viruses in blood.
Cotton, fleece, and beads.
NEEDLE-FREE INSULIN MAY COME FOR DIABETICS, RESEARCHERS SAY.
Bilirubin: both villain and hero? (Biomedicine).
Proof of burden: scores of contaminants course through people's veins.
Two new reports show industrial toxins common in human bodies.
Better blood: new tool removes agent of brain disease.

Terms of use | Copyright © 2016 Farlex, Inc. | Feedback | For webmasters