Nanometer sized sensors with biological transducers

描述(申请人提供)：在过去的二十年里，在复杂生物环境的分析方面取得了重大进展。利用指示剂染料或蛋白质进行荧光成像已发挥了重要作用，但也存在明显的局限性，包括毒性、化学稳定性和体系的扰动。虽然对于有荧光指示剂或离子载体的各种离子和小分子非常有用，但由于缺乏合适的指示剂或缺乏固有的光学或电化学活性，与化学和生物相关的大类分析物难以被检测到。在化学传感应用中使用膜受体、离子通道和分子转运体具有几个潜在的优势，因为许多这样的膜蛋白对小分子和/或基于蛋白质的配体具有高度的选择性，并且通常表现出高亲和力结合，这可能转化为传感器的高灵敏度。在这里，我们提出了一类新的纳米尺寸的仿生化学传感器，嵌入了膜蛋白，用于细胞内、体内和环境标记、跟踪和传感应用。为了实现这样一个传感器平台，我们将从一系列可以化学交联的脂类中创建磷脂微囊，并用重组的膜蛋白对微囊进行功能化。我们传感器平台的主要特点是：a)由可聚合脂质和脂质复合材料自组装形成的磷脂膜；b)结合的生物信号转导元件，例如受体；c)用于启动细胞摄取和传感器定位的外部膜元件；以及d)用于产生光学信号的指示剂或报告元件。这种模块化的传感器几何结构将提供一个通用平台，可用于方便地设计各种传感器。

DESCRIPTION (provided by applicant): The past two decades have witnessed significant advances in the analysis of complex biological environments. Fluorescence imaging utilizing indicator dyes or proteins has played an important role but also suffers from significant limitations including toxicity, chemical stability and perturbation of the system. Though quite useful for a variety of ions and small molecules where fluorescent indicators or ionophores are available, large categories of chemically and biologically relevant analytes elude detection due to a lack of suitable indicators or lack of intrinsic optical or electrochemical activity. The use of membrane receptors, ion channels and molecular transporters in chemical sensing applications presents several potential advantages over traditional reporters as many such membrane proteins are highly selective to small molecule and/or protein based ligands and typically demonstrate high affinity binding that may translate to high sensitivity of the sensor. Here we propose a new class of nanometer-sized, biomimetic chemical sensors with embedded membrane proteins for intracellular, in vivo and environmental labeling, tracing and sensing applications. To realize such a sensor platform, we will create phospholipid vesicles from a series of lipids that can be chemically crosslinked and we will functionalize the vesicles with reconstituted membrane proteins. The key features of our sensor platform are: a) a phospholipid membrane formed from self assembly of polymerizable lipids and lipid composites; b) incorporated biological signal transduction elements, e.g. receptors; c) external membrane elements that serve to initiate cellular uptake and localization of the sensor; and d) indicator or reporter elements that serve to generate an optical signal. This modular sensor geometry will provide a general platform that can be utilized to readily design a wide variety of sensors.