Wooten S L, Petersen J N, Van Wie B J
Chemical Engineering Department, Washington State University, Pullman 99164-2710.
J Biomech Eng. 1991 Feb;113(1):11-20. doi: 10.1115/1.2894078.
To obtain more efficient operation of a COBE Model 2997 clinical cell separator using either a Single Stage II (SS II) or a Dual Stage separation chamber, modifications were made to allow complete computer control. Product cell density was detected using an optical sensor and controlled by automatic feedback through a microcomputer interface. Control was accomplished by automatically adjusting the red blood cell (RBC) and plasma product flow rates using a proportional-integral (PI) algorithm. Results show that, using either chamber, the product cell density can be maintained at a preselected value for extended periods of time without operator intervention. This system allowed investigation of optimal operating regions for plateletpheresis and leukapheresis procedures. The effects of centrifuge rpm and controller set point on centrifuge operation were investigated using a second order factorial experimental design. Theoretical significance of model parameters was assessed with the aid of a hindered settling model and simple reasoning about the interface position relative to the collection port. The results suggest that, in either chamber, the optimum operating region for plateletpheresis procedures occurs at moderate controller set points and high centrifuge rpm. The resultant operating efficiency and product purity values are approximately 63 percent and 0.65 respectively in the SS II chamber and approximately 70 percent and 0.70 respectively in the Dual Chamber. In the SS II, the optimum operating region for leukapheresis procedures occurred at high controller set point values for any centrifuge rpm above 1200 with an operating efficiency near 100 percent. However, in the Dual Chamber, the optimum operating region for leukapheresis procedures occurred at high controller set points and high centrifuge rpm's, again providing an operating efficiency near 100 percent.
为了使用单级II型（SS II）或双级分离室更高效地操作COBE 2997型临床细胞分离器，进行了改进以实现完全计算机控制。使用光学传感器检测产品细胞密度，并通过微机接口进行自动反馈控制。通过使用比例积分（PI）算法自动调节红细胞（RBC）和血浆产品流速来实现控制。结果表明，使用任一分离室，产品细胞密度都可以在无需操作员干预的情况下长时间维持在预选值。该系统允许研究血小板单采和白细胞单采程序的最佳操作区域。使用二阶析因实验设计研究了离心机转速和控制器设定点对离心机操作的影响。借助受阻沉降模型和关于界面相对于收集端口位置的简单推理评估了模型参数的理论意义。结果表明，在任一分离室中，血小板单采程序的最佳操作区域出现在中等控制器设定点和高离心机转速下。在SS II分离室中，所得操作效率和产品纯度值分别约为63%和0.65，在双级分离室中分别约为70%和0.70。在SS II中，对于任何高于1200的离心机转速，白细胞单采程序的最佳操作区域出现在高控制器设定点值，操作效率接近100%。然而，在双级分离室中，白细胞单采程序的最佳操作区域出现在高控制器设定点和高离心机转速下，操作效率同样接近100%。
