Single File Flow of Biomimetic Beads for Continuous SERS Recording in a Microfluidic Device

Figure 6

(a) TEM image of a AuNS targeted PS bead, little particles can be observed on the curvature, which are identified as AuNS in the inset magnifications. (b) Sketch of the objective of the μ-Raman over the microchannel. (c) Optical microscope images of the microfluidic device. A PS bead is caught just before entering on the sampling area (left). The elongated shape of the laser spot allows getting SERS signals from the AuNS-PS bead for a prolonged period (right). (d) Raman spectrum recorded at 815 s, where both the SERS-AuNS signal at 688 cm⁻¹ and the PDMS peak at 710 cm⁻¹ are observed. (e) Signals recorded at the fixed Raman shift of 688 cm⁻¹ during the flowing of the nanoparticles in the microchannel.

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