Measurement of glucose consumption by hybridoma cells growing in hollow fiber cartridge bioreactors: use of blood glucose self-monitoring devices.

Two different types of blood glucose self-monitoring device, designed for use by diabetics (Accu-Chek Advantage* and Accu-Chek III*), were evaluated for the purpose of monitoring glucose concentration in tissue culture media. The Accu-Chek Advantage* meter was found to systematically overestimate the glucose concentration in a variety of commonly used tissue culture media by 50-90%, in comparison with their formulated glucose concentration. The Accu-Chek III* meter reliably estimated glucose concentrations from 100 to 300 mg/dl and overestimated glucose concentrations above 300 mg/dl. The systematic overestimation of glucose concentration in tissue culture fluids by the Accu-Chek Advantage* meter was further investigated. A standard curve was constructed and the meter reading was found to be linearly related to the actual glucose concentration and the best linear fit was given by the formula y = -43.504 + 1.9246x, where y is the meter reading and x is the actual glucose concentration. Rearranging the equation to make x the subject gave the following algorithm x = (y + 43.504) divided by 1.9246 which could be used to correct the 'raw' meter reading. The mean corrected glucose concentrations deviated from the formulated glucose concentration by less than 3.5% in five media tested, indicating that this meter is more than adequate for monitoring glucose consumption by cells growing in hollow fiber cartridge bioreactors, when used in conjunction with this correction factor.