Biomedical Engineering Reference
In-Depth Information
Fig. 3.10
Schematics of QD-nanobarcoded microbead system for high-throughput gene expres-
sion analysis.
a
Pseudocolor picture of the microbeads embedded with QDs.
b
Example spectra
of the beads coded with different mixture of QDs.
c
Construction of the nanobarcoded micro-
beads. Each bead has a distinctive ratio of four different QDs, allowing identification by a char-
acteristic spectral nanobarcode. The transcript-specific oligonucleotide probes are conjugated
with the bead surface. Therefore, each spectral-barcoded bead detects a specific oligonucleo-
tide determined by the probe.
d
Gene expression monitoring and quantification sandwich assay.
The nanobarcoded microbead-attached oligo probes capture biotinylated cRNA sample through
hybridization, the cRNA is further sandwiched by the 655-nm streptavidin QDs (or 705, 800 nm)
to be quantified. The gene expression variation is measured by fluorescence levels upon imag-
ing with the Mosaic scanner (Quantum Dot Corp.). Reproduced with permission from Ref. [
35
].
Copyright 2006, American Chemical Society
