Production of Quantum Dot Barcodes Using Biological Self‐Assembly

Abstract

A new strategy to produce stable barcodes using biological self‐assembly of streptavidin‐ and biotin‐functionalized quantum dots is reported. Such systems are of potential use in multiplexed immunoassay and nucleic acid hybridization assays.

Quantum dot incorporated Bacillus spore as nanosensor for viral infection

“…This similarity can be attributed to the permeation of QDs into the SMMs. That is, the surface of the QDSMs also had functional groups of carboxylic acids and amines that helped immobilize capture probes on the microspheres surface via carbodiimide or glutaraldehyde chemistry (Li et al, 2009a(Li et al, , 2009bMa et al, 2007;Raez et al, 2007;Rauf et al, 2009;Song et al, 2011). The carboxylic acid (pKa of 3.07; pKa of 6.21) and amino group (pKa of 8.98) concentrations of the QDSMs were 3.39 × 10 -3 and 1.11 × 10 -3 mol•g −1 , respectively, as analyzed by potentiometric titrations (Fig.…”

“…Han et al were the first to apply QD-tagged 1.2 µm polymer microspheres to the multiplexed optical coding of DNA hybridization (Han et al, 2001). Fuelled by their studies, the following three preparation methods for optical QD-encoded microspheres were developed: (i) incorporation of QDs during microsphere synthesis (Joumaa et al, 2006;Li et al, 2005;Vaidya et al, 2007;Wang and Seo, 2008;Yang et al, 2006), (ii) deposition of QDs onto bead surfaces through layer-bylayer adsorption (Li et al, 2009a(Li et al, , 2009bRauf et al, 2009), and (iii) diffusion of hydrophobic QDs into polymeric microspheres. Encoded microspheres are usually prepared by embedding hydrophobic microspheres with hydrophobic QDs via porosity partitioning and entrapment or swelling (Bradley et al, 2005;Gao and Nie, 2004).…”

Suspension arrays based on nanoparticle-encoded microspheres for high-throughput multiplexed detection

“…Moreover, an extra layer is always needed to protect the QDs. Instead of utilizing electrostatic forces, Rauf and coworkers 159,160 deposited multilayer QDs onto microspheres containing magnetic nanoparticles by a biotin–streptavidin system (Fig. 12).…”

“…Schematic illustration for fabricating inorganic nanoparticle–composite microspheres using the LBL method and via the interaction of biological molecules 159 …”

Microfluidic Generation of Multifunctional Quantum Dot Barcode Particles

“…Many encoding strategies have been proposed for these barcode particles; these include incorporation of segmented nanorods, 3 photo-patterning, [4][5][6] as well as the use of photonic crystals, 7,8 fluorescent silica colloids, 9 and semiconductor quantum dots (QDs). [10][11][12][13][14][15][16] In particular, the semiconductor QDs hold immense promise as barcode elements because of their excellent optical properties such as simultaneous excitation of multiple wavelength-and-intensity with a single light source, minimal spectral width, and remarkable photo-stability. In particular, the semiconductor QDs hold immense promise as barcode elements because of their excellent optical properties such as minimal spectral width, and remarkable photo-stability.…”