Quantum bioconjugation

Quantum dot bioconjugates for ultrasensitive nonisotopic detection. Science, 281, 2016-2018. 

Jaiswal, J. K., Mattoussi, H., Mauro, J. M. and Simon, S. M. (2003). Long-term multiple color imaging of live cells using quantum dot bioconjugates. Nat. Biotechnol. 21, 47-51. 

Clarke, S. J., Hollmann, C. A., Aldaye, F. A. and Nadeau, J. L. (2008). Effect of ligand density on the spectral, physical, and biological characteristics of CdSe/ZnS quantum dots. Bioconjug. Chem. 19, 562-8. 

Hering, V. R., Gibson, G., Schumacher, R. I., Faljoni-Alario, A. and Politi, M. J. (2007). Energy transfer between CdSe/ZnS core/shell quantum dots and fluorescent proteins. Bioconjug. Chem. 18, 1705-8. 

Ballou B, Lagerholm BC, Ernst LA, Bruchez MP, Waggoner AS (2004) Noninvasive imaging of quantum dots in mice. Bioconjug Chem 15 79-86... 

The following sections discuss many of the major particle types and provide bioconjugation options for the coupling of ligands to the surface of functionalized particles. Some additional nanoparticle constructs, including gold particles, dendrimers, carbon nanotubes, Buckyballs and fullerenes, and quantum dots are discussed more fully elsewhere (see Chapter 7 Chapter 9, Section 10 Chapter 15 and Chapter 24). 

Babu, P., Sinha, S., and Surolia, A. (2007) Sugar-quantum dot conjugates for a selective and sensitive detection of lectins. Bioconjugate Chem. 18, 146-151. 

Medintz, I L., Konnert, J.H., Clapp, A.R., Stanish, I., Twigg, M.E., Mattoussi, H., Mauro, J.M., and Deschamps, J.R. (2004) A fluorescence resonance energy transfer-derived structure of a quantum dot-protein bioconjugate nanoassembly. Proc. Natl. Acad. Sci. USA 101(26), 9612-9617. 

It is difficult to predict the effect of surface functionalization on the optical properties of nanoparticles in general. Surface ligands have only minor influence on the spectroscopic properties of nanoparticles, the properties of which are primarily dominated by the crystal field of the host lattice (e.g., rare-earth doped nanocrystals) or by plasmon resonance (e.g., gold nanoparticles). In the case of QDs, the fluorescence quantum yield and decay behavior respond to surface functionalization and bioconjugation, whereas the spectral position and shape of the absorption and emission are barely affected. 

For both organic dyes and QDs, bioconjugation often leads to a decrease in fluorescence quantum yield and thus typically also in emission lifetime. Parameters that can affect label fluorescence are the chemical nature and the length of the spacer and, at least for organic dyes, the type of neighboring biomolecules like oligonucleotides or amino acids in the bioconjugated form. 

Despite the promising possibilities offered by the different types of nanoparticles, their routine use is still strongly limited by the very small number of commercially available systems and the limited amount of data on their reproducibility (in preparation, spectroscopic properties, and apphcation) and comparability (e.g., fluorescence quantum yields, stability) as well as on their potential for quantification. To date, no attempt has yet been published comparing differently functionalized nanoparticles from various sources (industrial and academic) in a Round Robin test, to evaluate achievable fluorescence quantum yields, and batch-to-batch variations for different materials and surface chemistries (including typical ligands and bioconjugates). Such data would be very helpful for practitioners and would present the first step to derive and establish quality criteria for these materials. 

Wang Q, Xu Y, Zhao X, Chang Y, Liu Y, Jiang L, Sharma J, Seo DK, Yan H (2007) A facile one-step in situ functionalization of quantum dots with preserved photoluminescence for bioconjugation. J Am Chem Soc 129 6380-6381... 

Xing Y et al (2007) Bioconjugated quantum dots for multiplexed and quantitative immuno-histochemistry. Nat Protoc 2 1152-1165... 

Wang D, Rogach AL, Caruso F (2002) Semiconductor quantum dot-labeled microsphere bioconjugates prepared by stepwise self-assembly. Nano Lett 2 857-861... 

Dintz IL, Uyeda HT, Goldman ER, Mattoussi H (2005). Quantum dot bioconjugates for imaging, labelling and sensing. Nature Mater. 4 435 146. 

NANOSCALE SENSING ASSEMBLIES USING QUANTUM DOT-PROTEIN BIOCONJUGATES... 

Goldman, E. R., I. L. Medintz, A. Hayhurst, G. P. Anderson, J. M. Mauro, B. L Iverson, G. Georgiou, and H. Mattoussi. Self-assembled luminescent CdSe-ZnS quantum dot bioconjugates prepared using engineered poly-histidine terminated proteins. Anal. Chim. Acta 534, 63-67 (2005). 

Naval Research Laboratory 4555 Overlook Avenue SW Washington, DC, 20375 Chemistry Division/6112 Ph 202.404.3337 (Greg E. Collins) Greg.collins nrl.navy.mil Optical Sciences Division/5611 Ph 202.767.9473 (Hedi Mattoussi) hedimat ccs.nrl.navy, mil www.nrl.navy.mil Laboratory on a chip for explosive detection, quantum dot-protein bioconjugates, biosensors, UAV radar, and much more in basic research. 

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