Apparatus for delivering a controlled dosage of a chemical substance

An apparatus for delivering a controlled dosage of a chemical substance to a cell culture, the apparatus comprising:

• a plurality of vessels, each vessel containing a different known concentration of the same chemical substance;
• valving means having a plurality of inlet and a single outlet and having means for selectively connecting in fluid communication a preselected inlet to the single outlet;
• first conduit means for fluidly connecting each vessel to a corresponding inlet of the valving means;
• cell culture means for containing a cell culture, said cell culture means being in fluid connection with the outlet of the valving means and having an initial concentration of the chemical substance;
• second conduit means for fluidly connecting the single outlet of the valving means to the cell culture means;
• means for providing a transport force to the chemical substance in a flow controlled manner for delivering the chemical substance to the cell culture means and being in fluid communication with the outlet of the valving means and the cell culture means;
• and
• control means for controlling the valving means having means for providing input signals and means for providing signals indicative of a desired program of administration such that a preselected inlet is fluidly connected to the outlet for presenting a first preselected known concentration of the chemical substance to the cell culture means, and for controlling the means for providing a transport force to the chemical substance to effect a selected rate of delivery, including means for controlling the concentration of the chemical substance in the cell culture means according to the program of administration corresponding to the equation ##EQU18## wherein t=integration time interval
• V=volume of fluid within the cell culture means in which the chemical substance is being delivered
• R=the rate of delivery of the chemical substance to the cell culture means
• C.sub.i =the initial concentration level of the chemical substance in the integration time interval within the cell culture means
• C.sub.(t) =the final concentration of the chemical substance in the integration time interval within the cell culture means
• C.sub.s =the concentration of the chemical substance being delivered in the integration time interval from the vessels into the cell culture means
• wherein the means for controlling the concentration selects values of R/V and C.sub.s such that the concentration change between C.sub.i and C.sub.(t) is linear and the control means for controlling the valving means selectively switches among the vessels to choose C.sub.s for each integration time interval in response to the desired program of administration.