Abstract: The invention provides a process and apparatus for preparing chlorosilane from the reaction of very finely divided ultra-pure silicon with hydrogen chloride, the very finely divided ultra-pure silicon being fed into a solid bed of metallurgical silicon, the feed line for ultra-pure silicon and the fixed bed having a certain minimum temperature.

Abstract: The invention relates to a method for determining the isoform composition of erythropoietin, comprising the following steps: a) isoelectrical focusing of a sample comprising erythropoietin in a gel over a pH range having a lower limit of 2.5 to 3.5 and an upper limit of 5 to 8, wherein the sample comprising erythropoietin originates from a culture supernatant of erythropoietin producing eukaryotic cells; b) transferring of the proteins comprised and separated in the gel to a membrane; c) verifying the erythropoietin bound to the membrane by specific antibodies; and to a method for in-process control of culture supernatants of erythropoietin producing eukaryotic cells during the fermentative production process.

Abstract: The present invention relates to a process for the fermentative continuous production of erythropoietin, where eukaryotic erythropoietin-producing cells are cultured in a perfusion reactor while retaining the cells, the glucose concentration in the culture supernatant being adjusted via the perfusion rate and the cell number via the cell retention rate and/or the outward transferal of defined amounts of cell-containing culture medium from the bioreactor within preset zones.

Abstract: The present invention relates to a method for preparing erythropoietin, wherein culture supernatant of erythropoietin-producing eukaryotic cells containing erythropoietin are subjected to the following steps: a) Removing the cell components; and b) treating the product from a) to the following chromatography steps in the sequence indicated i) reversed phase chromatography; ii) anion exchange chromatography; iii) hydroxyapatite chromatography.

Abstract: A process for preparing enantiomerically enriched amines by reacting a ketone with ammonia or an ammonium salt and a reducing agent in the presence of a catalytic system comprising the components: a) an amino acid transaminase, b) an alpha-amino acid which is a substrate of the amino acid transaminase, c) an amino acid dehydrogenase suitable for preparing the alpha-amino acid, d) NAD(P)+ and e) an NAD(P)+-reducing enzyme, which reacts NAD(P)+ with the reducing agent to give NAD(P)H. The process can be carried out with catalytic amounts of alpha-amino acid and NAD(P)+, and enables an enantioselective reductive amination of ketones.