ELECTRODE POSITIONING BY ACCESS ADMITTANCE

这个子项目是许多利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 通过自参考技术检测到的化学信号不可避免地是距离依赖性的，这是由分析物通过细胞外基质的扩散引起的。 显然，这需要在离电池特定距离处可重复地放置电极。 不幸的是，探针的手动放置可能相当困难，并且限于细胞的x-y平面中的高对比度边界。 提供用于确定距离的仪器方法将不仅允许从z轴分析细胞，还将另外提供用于量化进行测量的距离的可再现手段，允许比较单个细胞上或多个细胞之间的多个点。 我们的目标是实现阻抗反馈来测量和控制样品-探针距离。 在短期内，该技术将应用于通量测量的距离控制。 从长远来看，这项技术将使我们能够将扫描显微镜添加到我们的分析工具箱。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Chemical signals detected by the self-referencing technique are inevitably distance dependent, resulting from diffusion of the analyte through the extracellular matrix. Obviously this necessitates the reproducible placement of electrodes at specific distances from the cell. Unfortunately, manual placement of the probe can be quite difficult and is limited to the high contrast boundary in the x-y plane of the cell. Providing an instrumental method for determining distance would not only allow analysis of the cell from the z axis, it would additionally provide a reproducible means for quantifying the distance at which measurements are taken, allowing comparison of multiple points on a single cell or among multiple cells. Our goal is the implementation of impedance feedback to measure and control the sample-probe distance. In the short-term this technology will be applied to the control of distance for flux measurements. In the long-term this technology will allow us to add scanning microscopy to our analytical toolbox.