文档介绍：Molecular Principles of Biomaterials Spring 2003
Lecture 18: Biosensors
Last time: engineering intracellular delivery
Drug targeting
Today: biosensor device classes
Detection methods
Overview of biosensor technology
Classes of biosensor devices
External analysis/detection
o Large instruments
o Objectives
Maximum sensitivity
Highest throughput
o Samples probed
Biochemical
Cell populations
Intracellular (single cells)
Field detection
o Usually simpler, need to be more robust
In vivo detection
o Usually catheter/needle-based for minimal invasiveness, with detector outside body
Classes of sensor mechanisms1
Capture-based
Binding of labeled analyte to capture reagent
Binding of unlabeled analyte to capture reagent triggers detectable signal
Catalysis2
Enzymatic reaction generates a detectable product
o Change in proton concentration, release of O2, NH3, CO2
o Release of metals, halides
o Ion/electron transfer
o Change in optical properties (. production of a colored product)
Cell-based
Single-cell-based
o Binding of analyte to cell surface receptor triggers detectable signal
Tissue-based biosensors3
o Binding of analyte to one cell type triggers cell-cell interactions and signaling cascades that can be
detected
Lecture 18 – Biosensors 1 of 6