Monitoring DNA hybridization using optical microcavities

Optics Letters (Impact Factor: 3.29). 11/2013; 38(22):4690-3. DOI: 10.1364/OL.38.004690
Source: PubMed


The development of DNA analysis methods is rapidly expanding as interest in characterizing subtle variations increases in biomedicine. A promising approach is based on evanescent field sensors that monitor the hybridization process in real time. However, one challenge is discriminating between nonspecific and specific attachment. Here, we demonstrate a hybridization sensor based on an integrated toroidal optical microcavity. The surface is functionalized with ssDNA using an epoxide method, and the evanescent wave of the microresonator excites a fluorescent label on the complementary ssDNA during hybridization. Based on a temporal analysis, the different binding regimes can be identified.

Download full-text


Available from: Andrea Armani, Apr 04, 2014
  • [Show abstract] [Hide abstract]
    ABSTRACT: While many new label-free optical sensing techniques are focusing on increasing the sensitivity or decreasing the limit of detection, the balance between sensitivity, specificity and collection efficiency are critical, particularly for detection in complex media. For example, although high Q optical resonant cavities are inherently sensitive, the collection efficiency of these devices is quite poor, particularly when compared to sensors with larger active sensing areas. By optimizing all three parameters, even further advancements in sensing technologies are possible.
    No preview · Article · Nov 2013 · Proceedings of SPIE - The International Society for Optical Engineering
  • [Show abstract] [Hide abstract]
    ABSTRACT: Optical cavities have successfully demonstrated the ability to detect a wide range of analytes with exquisite sensitivity. However, optimizing other parameters of the system, such as collection efficiency and specificity, have remained elusive. This presentation will discuss some of the recent work in this area, including 3D COMSOL Multiphysics models including mass transfer and binding kinetics of different cavity geometries and covalent attachment methods for a wide range of biological and synthetic moieties. A few representative experimental demonstrations will also be presented.
    No preview · Conference Paper · Mar 2014
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Label-free sensors based on electrical, mechanical and optical transduction methods have potential applications in numerous areas of society, ranging from healthcare to environmental monitoring. Initial research in the field focused on the development and optimization of various sensor platforms fabricated from a single material system, such as fiber-based optical sensors and silicon nanowire-based electrical sensors. However, more recent research efforts have explored designing sensors fabricated from multiple materials. For example, synthetic materials and/or biomaterials can also be added to the sensor to improve its response toward analytes of interest. By leveraging the properties of the different material systems, these hybrid sensing devices can have significantly improved performance over their single-material counterparts (better sensitivity, specificity, signal to noise, and/or detection limits). This review will briefly discuss some of the methods for creating these multi-material sensor platforms and the advances enabled by this design approach.
    Full-text · Article · Apr 2014 · Sensors
Show more