Sandra Sommerfeld

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The single-stage equilibrium aqueous two-phase extraction (ATPE) of human antibodies from a Chinese hamster ovary (CHO) cells supernatant was investigated. The performance of polyethylene glycol 3350 (PEG 3350)/phosphate aqueous two-phase systems (ATPS) was evaluated by studying several experimental conditions, such as pH, ionic strength, volume ratio and(More)
The biotech industry is, nowadays, facing unparalleled challenges due to the enhanced demand for biotechnology-based human therapeutic products, such as monoclonal antibodies (mAbs). This has led companies to improve substantially their upstream processes, with the yield of monoclonals increasing to titers never seen before. The downstream processes have,(More)
An aqueous two-phase extraction (ATPE) process based on a PEG/phosphate system was developed for the capture of human immunoglobulin G and successfully applied to a Chinese hamster ovary and a PER.C6® cell supernatant. A continuous ATPE process incorporating three different steps (extraction, back-extraction, and washing) was set up and validated in a pump(More)
The performance of a pilot scale packed differential contactor was evaluated for the continuous counter-current aqueous two-phase extraction (ATPE) of human immunoglobulin G (IgG) from a Chinese hamster ovary (CHO) cells supernatant (CS) enriched with pure protein. Preliminary studies have been firstly performed in order to select the dispersed phase(More)
Single-stage and multi-stage strategies have been evaluated and compared for the purification of human antibodies using liquid-liquid extraction in aqueous two-phase systems (ATPSs) composed of polyethylene glycol 3350 (PEG 3350), dextran, and triethylene glycol diglutaric acid (TEG-COOH). The performance of single-stage extraction systems was firstly(More)
Assisted by Deutsche Krebshilfe, the German cancer aid fund, a questionnaire for assessment of quality of life in patients with life-threatening skin tumours and disfiguring tumour sequels was developed at Fachklinik Hornheide between 1986 and 1988. A first step toward determining quality of life and for enhancing treatment-integrated rehabilitative work is(More)
In an investigation of psychosocial strain in persons having a facial or skin impairment, a total of 25 patients of Fachklinik Hornheide (a special clinic for the treatment of tumors, tuberculosis, and for facial and skin reconstruction) had participated in in-depth interviewing. It was found with unexpected clarity that these clients are exposed to a high(More)
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