重金属离子的灵敏、准确、简单、快速、价廉的现场检测是重大需求，但由于需要大型仪器和专业人员、灵敏度有限、步骤繁多、重现性差、分析周期长、成本高昂等不同原因，现有方法尚难满足。本项目以核酸适配体为特异性识别元件，以DNA三维纳米结构为偶联媒介，设计并合成功能化生物纳米材料，将靶标重金属离子固载于电极表面纳米尺度之内，形成吸附状态，以kV/s～MV/s扫描速度的快速扫描伏安法为激发源，创立快速扫描吸附伏安法。在既定工作条件下，峰电流与扫描速度成正比，电化学信号增强万倍至千万倍，可检测pmol/L～fmol/L级重金属离子。基于在线电位预补偿原理，设计一体化快速扫描电路系统，实时消除欧姆降和充电电流影响，结合丝网印刷电极，开发手持式设备，构建纳米生物电化学传感平台，实现重金属离子的超灵敏、准确、简单、快速、价廉的现场检测，并可实际应用于生物、环境样品分析。具有重要科学意义、社会效益和应用前景。

There is a great demand for sensitive, accurate, simple, rapid and low-cost on-site detection of heavy metal ions. However, existing methods cannot fully satisfy the requirement due to various reasons such as the need of large apparatus and professionals, limited sensitivity, complicated procedure, poor repeatability, long analytical cycle and high cost, etc. In this proposal, functionalized bionanomaterials are designed and synthesized using aptamers for heavy metal ions as specific recognition device and DNA three-dimensional nanostructure as coupling media. Thus, adsorption state of target heavy metal ions can be formed by their immobilization on the surface of the electrode in nanometer scale. Then, fast scan adsorptive voltammetry can be established when fast scan voltammetry is used as excitation source with kV/s～MV/s potential scan rates. Under the given working conditions, peak currents are proportional to potential scan rates, electrochemical signals increase about thousands to millions times, and pmol/L～fmol/L heavy metal ions could be detected. Afterwards, integrated fast scan circuit system is designed based on the principle of on-line potential pre-compensation, which can eliminate the distortion of the ohmic drop and charge current in real time. Based on it, handheld devices can be developed in combination with screen-printed electrode, and nano-bio electrochemical sensing platform can be set up. Hence, ultrasensitive, accurate, simple, rapid, low-cost on-site detection methods for heavy metal ions can be achieved. And, it could be practically applied to biological and environmental samples analysis. Thus, this proposal has important scientific significance, social benefits and application prospects.