Publikationsserver der RWTH Aachen University
Untersuchung physiologischer Eigenschaften gefriergetrockneter und rehydrierter Erythrozyten
Abstract
dc:descriptionErythocytes, which have been freeze dried by a new method using ultra deep temperatures , developed at the Helmholtz Institute Aachen (cite{Rin00} were investigated with respect to their physiological properties. They differ in size as well as in shape from native erythrocytes. Only few of them show the typical discoid shape. They are smaller than the native erythrocytes. Freeze dried erythrocytes loose their osmotic properties. They do not hemolyse in pure water, suggesting alterations in membrane structure. A Westernblot confirmed of all membraneproteins, so that holes in the membrane seem to be the most likely explanation. It could bee shown, that substances like potassium, ascorbic acid and purines are able to penetrate the membrane, whereas hemoglobin is kept inside the erythrocyte. Oxidation from hemoglobin to methemoglobin occurs during freeze drying process and could not be avoided. With methylenblue and ascorbic acid two substances were used to reduce methemoglobin, which are already well known to be able to reduce methemoglobin and are proofed in clinical use. Ascorbic acid is able to reduce methemoglobin of freeze dried erythrocytes to the amount of 10 % which is also reached in native erythrocytes, but reduction occurs only within 24 hours and not within 3 hours like in native erythrocytes, even though onset of reaction is much faster than in freeze dried erythrocytes, due to permeability of membrane in respect to freeze dried erythrocytes. An active metabolism of freeze dried erythrocytes, like conversion from glucose to lactate, could not be shown.
Degree
thesis:*- Grantor dc:publisher
- Publikationsserver der RWTH Aachen University
- Year dc:date
- 2003
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Binding, Barbara
- Contributors dc:contributor
-
- Rau, Günter
Subjects
dc:subject × 4Rights
dc:rights- Statement dc:rights
-
- info:eu-repo/semantics/openAccess
- Language dc:language
- ger
Identifiers
dc:identifier.*- OAI identifier oai:identifier
- oai:publications.rwth-aachen.de:59086