一种新型检测肿瘤组织特征的等效电容测量系统的优化设计和可行性分析

摘要

Different stages of cancer cells and normal cells have significant difference in capacitance.Looking for an inexpensive, non-invasive method for early diagnosis of cancer,a high-resolution bio-tissue capacitance measurement system was designed.The system consisted of DDS module,voltage-current conversion circuit,matching inductor and simulation capacitive and peak detection circuit.When the system was driven by alternating current,the circuit would resonate.The breast equivalent capacitance could be cal-culated by matching inductor and resonant frequency.Different equivalent capacitor values would reflect the pathological stage.When the simulation capacitance was 100~1000 pF,the system capacitance resolution was 8 pF.The system can be used for bio-tissue e-quivalent capacitance measurements,providing a new diagnosis of cancer early warning.%不同阶段的癌细胞和正常细胞有明显的容抗特性差异，为寻找一种廉价、非介入式的、可连续实时检测的癌组织早期诊断方法，设计了并验证一套高分辨率的容抗测量系统。采用DDS 扫频技术、电压电流转换电路、匹配电感以及模拟乳腺容抗负载构成交变电流激励的LC谐振系统，测量谐振频率计算生物组织等效电容值，不同的电容值会反映病理阶段信息。在100～1000 pF的模拟电容负载测量中，测得该系统的电容分辨率达到8 pF。该系统可初步用于人体组织等效容抗测量，为癌组织的早期风险预警提供一种新的方法。