Abstract
Semiconductor quantum dots (QDs)-doped polystyrene (PS) microspheres with high luminescence were prepared using a self-assembly approach. Hydrophobic CdSe/ZnS QDs were first carboxylized by ligand exchange using mercaptocarboxylic acid. PS microspheres were separately encapsulated with polyethyleneimine via electrostatic interactions and then adsorbed with the carboxyl QDs to form QDs-doped microspheres. We then characterized the combinations using optical, electrical, and mechanical approaches and obtained the following findings: (i) microspheres can be fully coated by QD nanoparticles with a coverage rate of 1.0 pmole/cm2, in which QDs were evenly distributed on the surfaces; (ii) the anchored QDs exhibited similar optical property as they performed in isolated suspension; and (iii) the fluorescence of QDs-doped microspheres remained intact after stressed by ultrasound-induced cavitation, demonstrating the robustness of interactions between QDs and microspheres. The self-assembly approach developed in this study offered a facile and controllable strategy for preparation of QDs-encoded microparticles with high luminescence and stability.
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REFERENCES
J. Yang, M.P. Sena, and X. Gao: Quantum dot-encoded fluorescent beads for biodetection and imaging. Rev. Fluoresc. 4, 139 (2009).
A. Rogach, A. Susha, F. Caruso, G. Sukhorukov, A. Kornowski, S. Kershaw, H. Möhwald, A. Eychmüller, and H. Weller: Nano- and microengineering: Three-dimensional colloidal photonic crystals prepared from submicrometer-sized polystyrene latex spheres pre-coated with luminescent polyelectrolyte/nanocrystal shells. Adv. Mater. 12, 333 (2000).
A.L. Rogach, D. Nagesha, J.W. Ostrander, M. Giersig, and N.A. Kotov: “Raisin bun”-type composite spheres of silica and semiconductor nanocrystals. Chem. Mater. 12, 2676 (2000).
X. Gao and S. Nie: Doping mesoporous materials with multicolor quantum dots. J. Phys. Chem. B 107, 11575 (2003).
Y. Gong, M. Gao, D. Wang, and H. Mohwald: Incorporating fluorescent CdTe nanocrystals into a hydrogel via hydrogen bonding: Toward fluorescent microspheres with temperature-responsive properties. Chem. Mater. 17, 2648 (2005).
N. Gaponik, I.L. Radtchenko, G.B. Sukhorukov, H. Weller, and A.L. Rogach: Toward encoding combinatorial libraries: Charge-driven microencapsulation of semiconductor nanocrystals luminescing in the visible and near IR. Adv. Mater. 14, 879 (2002).
N. Joumaa, M. Lansalot, A. Théretz, A. Elaissari, A. Sukhanova, M. Artemyev, I. Nabiev, and J.H. Cohen: Synthesis of quantum dot-tagged submicrometer polystyrene particles by miniemulsion polymerization. Langmuir 22, 1810 (2006).
Y. Li, E.C.Y. Liu, N. Pickett, P.J. Skabara, S.S. Cummins, S. Ryley, A.J. Sutherland, and P. O’Brien: Synthesis and characterization of CdS quantum dots in polystyrene microbeads. J. Mater. Chem. 15, 1238 (2005).
C.N. Allen, N. Lequeux, C. Chassenieux, G. Tessier, and B. Dubertret: Optical analysis of beads encoded with quantum dots coated with a cationic polymer. Adv. Mater. 19, 4420 (2007).
X. Pan, M. Lu, D. Wu, and L. Gai: Synthesis and characterization of double-layer quantum-dots-tagged microspheres. IEEE Trans. Nanobiosci. 8, 13 (2009).
M. Han, X. Gao, J. Su, and S. Nie: Quantum-dot-tagged microbeads for multiplexed optical coding of biomolecules. Nat. Biotech. 19, 631 (2001).
T. Buranda, Y. Wu, and L.A. Sklar: Quantum dots for quantitative flow cytometry. Methods Mol. Biol. 699, 67 (2011).
Y. Wu, S.K. Campos, G.P. Lopez, M.A. Ozbun, L.A. Sklar, and T. Buranda: The development of quantum dot calibration beads and quantitative multicolor bioassays in flow cytometry and microscopy. Anal. Biochem. 364, 180 (2007).
Y. Xiang, H. Zhang, B. Jiang, Y. Chai, and R. Yuan: Quantum dot layer-by-layer assemblies as signal amplification labels for ultrasensitive electronic detection of uropathogens. Anal. Chem. 83, 4302 (2011).
L. Sun, X. Yu, M. Sun, H. Wang, S. Xu, J.D. Dixon, Y.A. Wang, Y. Li, Q. Yang, and X. Xu: Preparation of quantum dots encoded microspheres by electrospray for the detection of biomolecules. J. Colloid Interface Sci. 358, 73 (2011).
A. Sukhanova and I. Nabiev: Fluorescent nanocrystal-encoded microbeads for multiplexed cancer imaging and diagnosis. Crit. Rev. Oncol. Hematol. 68, 39 (2008).
M. Stroh, J.P. Zimmer, D.G. Duda, T.S. Levchenko, K.S. Cohen, E.B. Brown, D.T. Scadden, V.P. Torchilin, M.G. Bawendi, D. Fukumura, and R.K. Jain: Quantum dots spectrally distinguish multiple species within the tumor milieu in vivo. Nat. Med. 11, 678 (2005).
R. Di Corato, N.C. Bigall, A. Ragusa, D. Dorfs, A. Genovese, R. Marotta, L. Manna, and T. Pellegrino: Multifunctional nanobeads based on quantum dots and magnetic nanoparticles: Synthesis and cancer cell targeting and sorting. ACS Nano. 5, 1109 (2011).
Y. Chan, J.P. Zimmer, M. Stroh, J.S. Steckel, R.K. Jain, and M.G. Bawendi: Incorporation of luminescent nanocrystals into monodisperse core-shell silica microspheres. Adv. Mater. 16, 2092 (2004).
C. Graf, S. Dembski, A. Hofmann, and E. Ruhl: A general method for the controlled embedding of nanoparticles in silica colloids. Langmuir 22, 5604 (2006).
M. Kuang, D. Wang, H. Bao, M.Y. Gao, H. Möhwald, and M. Jiang: Fabrication of multicolor-encoded microspheres by tagging semiconductor nanocrystals to hydrogel spheres. Adv. Mater. 17, 267 (2005).
W.C. Chan and S. Nie: Quantum dot bioconjugates for ultrasensitive nonisotopic detection. Science 281, 2016 (1998).
W.W. Yu, L. Qu, W. Guo, and X. Peng: Experimental determination of the extinction coefficient of CdTe, CdSe, and CdS nanocrystals. Chem. Mater. 15, 2854 (2003).
D.E. Gómez, I. Pastoriza-Santos, and P. Mulvaney: Tunable whispering gallery mode emission from quantum-dot-doped microspheres. Small 1, 238 (2005).
H. Mattoussi, A.W. Cumming, C.B. Murray, M.G. Bawendi, and R. Ober: Characterization of CdSe nanocrystallite dispersions by small angle x-ray scattering. J. Chem. Phys. 105, 9890 (1996).
J. Schmitt, P. Mächtle, D. Eck, H. Möhwald, and C.A. Helm: Preparation and optical properties of colloidal gold monolayers. Langmuir 15, 3256 (1999).
L.A. Crum, R.A. Roy, M.A. Dinno, C.C. Church, R.E. Apfel, C.K. Holland, and S.L. Madanshetty: Acoustic cavitation produced by microsecond pulses of ultrasound: A discussion of some selected results. J. Acoust. Soc. Am. 91, 1113 (1992).
D.L. Miller: A review of the ultrasonic bioeffects of microsonation, gas-body activation, and related cavitation-like phenomena. Ultrasound Med. Biol. 13, 443 (1987).
H.D. Liang, J. Tang, and M. Halliwell: Sonoporation, drug delivery, and gene therapy. Proc. Inst. Mech. Eng. Part H 224, 343 (2010).
W.G. Pitt, G.A. Husseini, and B.J. Staples: Ultrasonic drug delivery–a general review. Expert Opin. Drug Delivery 1, 37 (2004).
ACKNOWLEDGMENT
The authors would like to thank Ceramic Transducer Design Co., Ltd. (Taiwan, Republic of China) for the gift of a PZT transducer.
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Lee, YH., Tseng, CS. & Wei, YL. Fabrication and characterization of CdSe/ZnS quantum dots-doped polystyrene microspheres prepared by self-assembly. Journal of Materials Research 27, 2829–2836 (2012). https://doi.org/10.1557/jmr.2012.332
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DOI: https://doi.org/10.1557/jmr.2012.332