Frequently Asked Questions | XCell™ Lab Controller, XCell ATF® Devices
The XCell™ Lab controller increases process control, process monitoring and throughput relative to the C24 controller. Key features include 2X device capacity, support of the XCell ATF® 1 Device (0.5-2 L), precision pumping, permeate pressure sensor capability and configurable alarms.
Precision pumping delivers precise flow rates, even at high cell densities and viscosities
Permeate pressure recording enables real time filter status and fouling monitoring
Configurable alarms notify the user of key process events
XCell ATF® 1 (SU) device support with working volumes as low as 0.5-2 for reduced development media cost
Importantly, the pumping technology has been upgraded through integration of the flow sensor into a control logic loop. The improved performance maintains a linear relationship between the observed and theoretical flow rate up to viscosity values of 6 cp, improving robustness during development and manufacturing scale-up
XCell™ Lab 控制器也仅代表了完整 XCell ATF® Lab 系统的一部分，后者包括：
Software designed for visual process monitoring and control
Integrated flow and pressure sensors
XCell ATF® devices
Air and vacuum accessories (pump, manifold)
System engineering creates significant setup flexibility. The tablet monitor mounts both on the instrument or a lab shelf. The XCell ATF® 1 single-use device can be mounted to the edge of a benchtop or on top of a bench top. The pressure regulator and relief device can be mounted several different ways and may be located in a different room if required. Each manifold supports up to 4 controllers and each controller supports up to 2 devices, meaning a total of up to 8 XCell ATF® devices can be run on each manifold.
The XCell™ Lab ontroller supports two XCell ATF® devices (the legacy C24 controller supported only one), offering multiple benefits. The two XCell ATF® devices can be connected to either the same or different bioreactors. In either situation, using one less controller and, possibly one less bioreactor (connecting both ATF Devices to the same bioreactor), lab footprint can also be reduced.
Increased throughput: Connecting two XCell ATF® devices to two bioreactors increases throughput per controller. Execute DoE plans faster (relative to legacy C24) with more data acquired in parallel-or execute a larger DoE in the same amount of time.
Precision out-of-phase: Connecting and running two XCell ATF® devices to a single bioreactor provides an improved production scale-up model, minimizing filter oversizing during development. Use of a single controller with centralized data enables the volumes of two devices run out-of-phase to be matched through programming. In legacy systems, two XCell ATF® C24 controllers were required to control two devices connected to one bioreactor. Data on two different controllers necessitated matching flow rates through iterative manual adjustment, which was a tedious and error prone process.
第2个装置也可以简单地连接至生物反应器，以备使用（不运行），当第1个过滤器污染时，可以轻松地切换至第2个过滤器。
2个装置可以按独立、同相或异相模式运行。在大多数情况下，连接至单个生物反应器的2个装置会以异相模式运行，因其可使生物反应器维持恒定的体积。独立和同相模式不太可能使用 - 或仅保留用于非常特殊的应用。
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模式 |
ATF DUAL BOX 状态 |
解释 |
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ATF DUAL (已同步) |
独立 |
每个XCell ATF® 装置独立运作，不需要考虑另一个装置的状态 |
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同相 |
每个装置的压力冲程在相同的时间发生。相似的，每个装置的排气冲程在相同的时间发生。 |
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异相 |
第一个装置的压力冲程匹配第二个装置的排气冲程，反之亦然。生物反应器体积维持恒定。 |
XCell™ Lab 控制器提供三种型号：单装置 (S)、双装置 (D) 以及带 P3 压力传感器的双装置控制器 (D-P)。单装置系统 (S) 可在Repligen现场服务工程师 (FSE) 的协助下，随时升级至双装置系统 (D)，FSE将在客户现场进行升级工作和测试。但是，S或D型号在购买之后，不能升级至D-P型号。
滤液压力传感器可提供实时的过滤器性能和污染特性。该数据可帮助确定何时应该更换过滤器，并优化规模放大预测。如果开发计划包括规模放大，我们建议采购 XCell™ Lab 控制器型号 XC-LAB-D-P。
精确的泵送可在整个强化工艺过程中提供精确的流速，即使在高细胞密度和粘度条件下。使用XCell™ Lab 控制器设置的流速是通过流量控制来实现的，而不是压力。A2B 管线上整合的流量传感器 (XCell ATF® 装置与生物反应器之间的连接) 测量流速和隔膜泵置换体积。控制算法分析流量传感器，然后设置隔膜泵和流速控制。对流速进行修正，以符合用户指定的设定点，优化XCell ATF® 装置反冲和过滤器清洁。通过理论流速和观察流速之间的相关性，已经证实了用户指定设定点与实际流速之间的匹配性，该相关性可在高达6 cP的粘度条件下得以维持(参见下图)。6 cp 对应约 150-200 VCD，具体取决于细胞系。