A guiding light: spectroscopy on digital microfluidic devices using in-plane optical fibre waveguides.
Anal Bioanal Chem
; 407(24): 7467-75, 2015 Sep.
Article
em En
| MEDLINE
| ID: mdl-26232932
ABSTRACT
We present a novel method for in-plane digital microfluidic spectroscopy. In this technique, a custom manifold (.stl file available online as ESM) aligns optical fibres with a digital microfluidic device, allowing optical measurements to be made in the plane of the device. Because of the greater width vs thickness of a droplet on-device, the in-plane alignment of this technique allows it to outperform the sensitivity of vertical absorbance measurements on digital microfluidic (DMF) devices by â¼14×. The new system also has greater calibration sensitivity for thymol blue measurements than the popular NanoDrop system by â¼2.5×. The improvements in absorbance sensitivity result from increased path length, as well as from additional effects likely caused by liquid lensing, in which the presence of a water droplet between optical fibres increases fibre-to-fibre transmission of light by â¼2× through refraction and internal reflection. For interrogation of dilute samples, stretching of droplets using digital microfluidic electrodes and adjustment of fibre-to-fibre gap width allows absorbance path length to be changed on-demand. We anticipate this new digital microfluidic optical fibre absorbance and fluorescence measurement system will be useful for a wide variety of analytical applications involving microvolume samples with digital microfluidics.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Análise Espectral
/
Fibras Ópticas
/
Dispositivos Lab-On-A-Chip
Idioma:
En
Revista:
Anal Bioanal Chem
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Canadá