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Space- and time-resolved spectrophotometry in microsystems.

ABSTRACT: This work describes a simple optical method for obtaining, in a single still-capture image, the continuous absorbance spectra of samples at multiple locations of microsystems. This technique uses an unmodified bright-field microscope, an array of microlenses, and a diffraction grating to disperse the light transmitted by samples of 10- to 500-microm dimensions. By analyzing in a single image the first-order diffracted light, it is possible to collect the full and continuous absorbance spectra of samples at multiple locations (to a spatial resolution of approximately 8 microm) in microwells and microchannels to examine dynamic chemical events (to a time resolution of <10 ms). This article also discusses the optical basis of this method. The simultaneous resolution of wavelength, time, and space at a scale <10 microm provides additional capabilities for chemical and biological analysis.

SUBMITTER: Damean N

PROVIDER: S-EPMC1177425 | biostudies-literature | 2005 Jul

REPOSITORIES: biostudies-literature

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Space- and time-resolved spectrophotometry in microsystems.

Damean Nicolae N Sia Samuel K SK Linder Vincent V Narovlyansky Max M Whitesides George M GM

Proceedings of the National Academy of Sciences of the United States of America 20050708 29

This work describes a simple optical method for obtaining, in a single still-capture image, the continuous absorbance spectra of samples at multiple locations of microsystems. This technique uses an unmodified bright-field microscope, an array of microlenses, and a diffraction grating to disperse the light transmitted by samples of 10- to 500-microm dimensions. By analyzing in a single image the first-order diffracted light, it is possible to collect the full and continuous absorbance spectra of ...[more]

PMID: 16006503

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