Method for separating charged biologically active substances from liquids and the recovery thereof

Abstract

The present invention relates to a method for the at least temporary retention of charged biologically active substances such as endotoxins, viruses, and proteins from liquids, and optional later release for better determination. The object is achieved by a method for the at least temporary separation and / or detection of charged biologically active substances in a liquid by means of electrosorption and / or electrofiltration, comprising the following steps: a. providing a polymer membrane with a flat and porous metal coating at least on a first side of the polymer membrane; b. providing a counterelectrode; c. applying a voltage between the metal coating of the polymer membrane and the counterelectrode; d. bringing the polymer membrane and the counterelectrode into contact with the liquid, with the contacting being performed such that the liquid generates at least one connection between the polymer membrane and the counterelectrode.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a Continuation of U.S. patent application Ser. No. 16 / 473,640 filed Jun. 26, 2019, which is a National Stage Entry of PCT / EP2017 / 084721 filed Dec. 28, 2017, which claims priority from German Patent Application Serial No. 102016125818, filed Dec. 28, 2016, the entire disclosures of which are incorporated herein by reference.TECHNICAL FIELD[0002]The present invention relates to a method for the at least temporary retention of charged biologically active substances such as endotoxins, viruses, and proteins from liquids, and optional later release for better determination.BACKGROUNDBackground Information[0003]Endotoxins are lipopolysaccharides (LPS) and components of the outer membrane of the cell wall of Gram-negative bacteria. They consist of a lipophilic lipid that is anchored in the membrane and a hydrophilic polysaccharide, which represents the antigenic properties. Endotoxins are released upon lysis of the bacterial ...

AI Technical Summary

Benefits of technology

The present invention relates to an electrosorption and / or electrofiltration device which has a membrane with improved virus retention. This is achieved by reducing the porosity of the membrane and increasing the thickness of the metal coating or the pore size of the membrane. The device without a coating has a low level of virus retention, while the membrane with a coating has a higher virus retention. This is because the coating reduces the charge of the membrane and increases the zeta potential, which attracts more viruses.

Problems solved by technology

However, endotoxins can only be determined in clear, undyed fluids when using this test.

Direct determination of endotoxins in human blood is therefore not possible.

This test requires special training, has high specific costs, and also takes much longer than the LAL test.

Possible electrosorption on the conductive surface of a ceramic membrane allows for a more flexible sorption of substances but is very expensive to achieve.

In addition to the advantages of membranes that have been positively or negatively charged by chemical treatment—namely the combination of mechanical filtration and adsorption—they also have a drawback.

In particular, this represents an additional expense during the recovery of active substances such as proteins through concentration.

It is therefore not possible to obtain endotoxins—from blood, for example—by means of permanently charged membranes in order to subsequently convert them into a colorless liquid and forward them for easier analysis.

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