1. Multifunctional Analytical Platform on a Paper Strip: Separation, Preconcentration, and Subattomolar Detection
- Author
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Limei Tian, Andrew Brimer, Srikanth Singamaneni, Rajesh R. Naik, Abdennour Abbas, and Joseph M. Slocik
- Subjects
Chlorophyll ,Paper ,business.product_category ,Polymers ,Microfluidics ,Nanotechnology ,Chemical Fractionation ,engineering.material ,Spectrum Analysis, Raman ,Analytical Chemistry ,symbols.namesake ,Microscopy, Electron, Transmission ,Coating ,Spinacia oleracea ,Microfiber ,Polyamines ,Plasmon ,Fluorescent Dyes ,Detection limit ,Nanotubes ,Microchannel ,Plant Extracts ,Chemistry ,Microfluidic Analytical Techniques ,Carotenoids ,Spectrometry, Fluorescence ,symbols ,engineering ,Nanorod ,Gold ,Sulfonic Acids ,business ,Raman scattering - Abstract
We report a plasmonic paper-based analytical platform with functional versatility and subattomolar (10(-18) M) detection limit using surface-enhanced Raman scattering as a transduction method. The microfluidic paper-based analytical device (μPAD) is made with a lithography-free process by a simple cut and drop method. Complex samples are separated by a surface chemical gradient created by differential polyelectrolyte coating of the paper. The μPAD with a starlike shape is designed to enable liquid handling by lateral flow without microchannel patterning. This design generates a rapid capillary-driven flow capable of dragging liquid samples as well as gold nanorods into a single cellulose microfiber, thereby providing an extremely preconcentrated and optically active detection spot.
- Published
- 2013
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