IEEE Trans Biomed Circuits Syst. 2011 Jun;5(3):223-30. doi: 10.1109/TBCAS.2010.2089794.
We present the design and implementation of a prototype complementary metal-oxide semiconductor (CMOS) conductometric integrated circuit (IC) for colony growth monitoring and specific sensing of Escherichia coli (E. coli) bacteria. The detection of E. coli is done by employing T4 bacteriophages as receptor organisms. The conductometric system operates by measuring the resistance of the test sample between the electrodes of a two-electrode electrochemical system (reference electrode and working electrode). The CMOS IC is fabricated in a TSMC 0.35-μm process and uses a current-to-frequency (I to F) conversion circuit to convert the test sample resistance into a digital output modulated in frequency. Pulsewidth control (one-shot circuit) is implemented on-chip to control the pulsewidth of the output digital signal. The novelty in the current work lies in the ability of the CMOS sensor system to monitor very low initial concentrations of bacteria (4×10(2) to 4×10(4) colony forming unit (CFU)/mL). The CMOS system is also used to record the interaction between E. coli and its specific receptor T4 bacteriophage. The prototype CMOS IC consumes an average power of 1.85 mW with a 3.3-V dc power supply.
我们提出了一种互补金属氧化物半导体（CMOS）导电集成电路（IC）的设计和实现，用于菌落生长监测和特定的大肠杆菌（E. coli）细菌感应。通过使用 T4 噬菌体作为受体生物来进行大肠杆菌的检测。导电系统通过测量两个电极（参考电极和工作电极）之间测试样品的电阻来工作。CMOS IC 是在 TSMC 0.35-μm 工艺中制造的，并使用电流到频率（I 到 F）转换电路将测试样品电阻转换为调制频率的数字输出。在芯片上实现了脉宽控制（单稳态电路），以控制输出数字信号的脉宽。当前工作的新颖之处在于 CMOS 传感器系统能够监测非常低的初始细菌浓度（4×10(2) 到 4×10(4) 集落形成单位（CFU）/mL）。CMOS 系统还用于记录大肠杆菌与其特定受体 T4 噬菌体之间的相互作用。原型 CMOS IC 消耗平均功率为 1.85 mW，采用 3.3-Vdc 电源。
