Journal: Biomicrofluidics

Article Title: Microliter-bioreactor array with buoyancy-driven stirring for human hematopoietic stem cell culture

doi: 10.1063/1.3380627

Figure Lengend Snippet: (a) Schematic of an individual microliter-bioreactor stirred by buoyancy-driven thermoconvection. A microfabricated heater on a silicon substrate is in direct contact with the external bottom of the well (∼32 mm2) and produces a local temperature hot spot, TH. The thermoelectric cooler, which is beneath the silicon wafer, maintains the overall bioreactor temperature near the incubator temperature, TC. (b) Schematic of the microliter-bioreactor array. A conventional 96-well plate is in contact with an electrical circuit microfabricated on a silicon wafer. An aluminum block between the silicon wafer and the thermoelectric cooler enhances temperature homogeneity. A PT100 temperature probe and PID controller maintain the thermoelectric cooler’s temperature at TC. (c) Top view of the microfabricated electrical circuit. It is composed of five rows with six parallel heaters, which correspond to the position of the wells (dashed red line) of the 96-well plate. Each microheater is serpentine shaped (see enlargement) to maximize the resistance. A different voltage (1.01–1.60 V) is applied to each row to perform cell cultures at five different stirring conditions.

Article Snippet: A thermoelectric cooler (CP-031; TE Technology, Traverse City, MI), paired with an aluminum block (8 mm thick), is in contact with the backside of the silicon substrate and set to T C . The temperature T C is regulated with a temperature probe (PT100, 10 mm, class A; RS Components, Milano, Italy) on the upper surface of the thermoelectric cooler and a Proportional-Integral-Devide (PID) controller (model 998, Watlow Electric Manufacturing Co., St Louis, MO).

Techniques: Blocking Assay