Valentin Jossen

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Spinner flasks are often used for microcarrie-based cultivations of human mesenchymal stem cells (hMSCs). Normally, they are not equipped with pH and dissolved oxygen (DO) probes. This application note describes the cultivation of hMSCs in single-use spinner flasks equipped with optical pH (SP-HP8) and DO (SP-PSt3) sensors for the first time. While reaching(More)
pH value and the concentration of dissolved oxygen (DO) are key parameters to monitor and control cell growth in cultivation studies. Reliable, robust and accurate methods to measure these parameters in cultivation systems in real time guarantee high product yield and quality. This mini-review summarises the current state of the art of pH and DO sensors(More)
Materials and methods Preliminary tests in disposable-spinners (100 mL culture volume, Corning) were used to determine two suitable media and MC-types for serum reduced expansions (< 10%) of human adipose tissue-derived stem cells (hADSCs; passage 2, Lonza). Using such optimized media-MC-combinations, hADSCs expanded 30 to 40fold, which compares well with(More)
The potential of human mesenchymal stem cells (hMSCs) for allogeneic cell therapies has created a large amount of interest. However, this presupposes the availability of efficient scale-up procedures. Promising results have been reported for stirred bioreactors that operate with microcarriers. Recent publications focusing on microcarrier-based stirred(More)
Stem cells have enormous potential in health and medical research due to their ability to differentiate into specialized cells and to self-renew. Applications can be seen in cell-based therapies, e.g. for the treatment of Parkinson's disease, type I diabetes, arthritis, burn victims, and cardiovascular diseases, as well as in tissue engineering of(More)
Power input is an important engineering and scale-up/down criterion in stirred bioreactors. However, reliably measuring power input in laboratory-scale systems is still challenging. Even though torque measurements have proven to be suitable in pilot scale systems, sensor accuracy, resolution, and errors from relatively high levels of friction inside(More)
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