Harrington Program of Biomedical Engineering, in the School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ 85287, USA.
Methods. 2013 May 15;61(1):39-51. doi: 10.1016/j.ymeth.2013.04.015. Epub 2013 Apr 26.
There is a critical need for more accurate, highly sensitive and specific assay for disease diagnosis and management. A novel, multiplexed, single sensor using rapid and label free electrochemical impedance spectroscopy tuning method has been developed. The key challenges while monitoring multiple targets is frequency overlap. Here we describe the methods to circumvent the overlap, tune by use of nanoparticle (NP) and discuss the various fabrication and characterization methods to develop this technique. First sensors were fabricated using printed circuit board (PCB) technology and nickel and gold layers were electrodeposited onto the PCB sensors. An off-chip conjugation of gold NP's to molecular recognition elements (with verification technique) is described as well. A standard covalent immobilization of the molecular recognition elements is also discussed with quality control techniques. Finally use and verification of sensitivity and specificity is also presented. By use of gold NP's of various sizes, we have demonstrated the possibility and shown little loss of sensitivity and specificity in the molecular recognition of inflammatory markers as "model" targets for our tuning system. By selection of other sized NP's or NP's of various materials, the tuning effect can be further exploited. The novel platform technology developed could be utilized in critical care, clinical management and at home health and disease management.
目前，人们迫切需要更准确、高灵敏度和高特异性的疾病诊断和管理检测方法。本研究开发了一种新型的、多重的、单传感器，采用快速、无标记的电化学阻抗谱调谐方法。在监测多个靶标时，关键的挑战是频率重叠。在这里，我们描述了规避重叠的方法，通过使用纳米颗粒（NP）进行调谐，并讨论了各种制造和表征方法来开发这种技术。首先，使用印刷电路板（PCB）技术制造传感器，并在 PCB 传感器上电镀镍和金层。还描述了将金 NP 与分子识别元件进行片外偶联（带有验证技术）。也讨论了标准的分子识别元件的共价固定化及其质量控制技术。最后还展示了灵敏度和特异性的应用和验证。通过使用各种大小的金 NP，我们已经证明了这种可能性，并表明在我们的调谐系统中，对炎症标志物等“模型”靶标的分子识别几乎没有灵敏度和特异性损失。通过选择其他尺寸的 NP 或不同材料的 NP，可以进一步利用调谐效果。所开发的新型平台技术可用于重症监护、临床管理以及家庭健康和疾病管理。
