Wu P, Ozturk S S, Blackie J D, Thrift J C, Figueroa C, Naveh D
Miles Biotechnology, Building 46, 4th and Parker Streets, PO Box 1986, Berkeley, California 94701, USA.
Biotechnol Bioeng. 1995 Mar 20;45(6):495-502. doi: 10.1002/bit.260450606.
On-line optical cell density probes were implemented to continuously monitor the cell densities in mammalian cell bioreactor and to achieve advanced bioreactor controls. We tested cell density probes from six manufacturers in high cell density bioreactors. When externally calibrated, Aquasant and Ingold backscattering probes produced the most linear probe responses (PR) versus cell density (CD), followed by the ASR and Cerex laser probes. Monitek and Wedgewood transmission probes had lower resolutions. All probes were tested in two murine hybridoma fermentations. Cell densities varied between 1 x 10(6) cells/mL to 20 x 10(6) cells/mL and the bioreactors were operated for 5 to 7 weeks. For our bioreactors, Aquasant, Ingold, ASR, Wedgewood, and Monitek probes gave satisfactory responses. Little fouling was observed with any probe at the end of 2 weeks. Fouling was a possibility after 3 weeks in one bioreactor but its effect can be easily corrected. Cell density control and specific perfusion control of bioreactors based on the Aquasant probe were achieved. Implementation of cell density probe based perfusion control, instead of "step perfusion adjustments" based on manual hemacytometer control, will result in smoother operation, healthier cultures, increased medium delivery efficiency, and reduced operational excursions.
在线光学细胞密度探头用于连续监测哺乳动物细胞生物反应器中的细胞密度，并实现先进的生物反应器控制。我们在高细胞密度生物反应器中测试了来自六个制造商的细胞密度探头。外部校准时，Aquasant和Ingold背散射探头的探头响应（PR）与细胞密度（CD）之间的线性关系最佳，其次是ASR和Cerex激光探头。Monitek和Wedgewood透射探头的分辨率较低。所有探头均在两种小鼠杂交瘤发酵中进行了测试。细胞密度在1×10⁶个细胞/mL至20×10⁶个细胞/mL之间变化，生物反应器运行5至7周。对于我们的生物反应器，Aquasant、Ingold、ASR、Wedgewood和Monitek探头给出了令人满意的响应。两周结束时，未观察到任何探头有明显污染。在一个生物反应器中，三周后有污染的可能性，但其影响可以很容易地纠正。基于Aquasant探头实现了生物反应器的细胞密度控制和特定灌注控制。实施基于细胞密度探头的灌注控制，而不是基于手动血细胞计数器控制的“逐步灌注调整”，将导致操作更平稳、培养物更健康、培养基输送效率提高以及操作偏差减少。
