Bioconjugates properties

Besides the chemoenzymatic approaches described above, where functional groups are added to allow for conjugation with other macromolecules, enzymes demonstrate other possibilities to obtain peptide- and protein-polymer conjugates, which are normally difficult to obtain by common chemical synthetic strategies. Enzyme responsiveness can be used to modulate bioconjugate properties in order to create hybrid materials with... 

Akcan M, Stroud MR, Hansen SJ, Clark RJ, Daly NL, Craik DJ, Olson JM (2011) Chemical re-engineering of chlorotoxin improves bioconjugation properties for tumor imaging and targeted therapy. J Med Chem 54 782-787... 

The syntheses, photophysical and electrochemical properties of [Ir(ppy)2(phen-NS-5)]PF6, (181), [Ir(ppy)2(phen-NHCOCH2I-5)]PF6, (182), and [Ir(ppy)2(phen-NH2-5)]PF6 are reported.342 Complexes (181) and (182) have been used to label amine- and sulfhydryl-modified oligonucleotides and human serum albumin to give luminescent bioconjugates. 

Luschtinetz F, Dosche C, Kumke MU (2009) Influence of streptavidin on the absorption and fluorescence properties of cyanine dyes. Bioconjugate Chem 20 576-582... 

Reddington MV (2007) Synthesis and properties of phosphonic acid containing cyanine and squaraine dyes for use as fluorescent labels. Bioconjugate Chem 18 2178-2190... 

Licha K, Hessenius C, Becker A, Henklein P, Bauer M, Wisniewski S, Wiedenmann B, Semmler W (2001) Synthesis, characterization, and biological properties of cyanine-labeled somatostatin analogues as receptor-targeted fluorescent probes. Bioconjugate Chem 12 44—50... 

Oswald B, Patsenker L, Duschl J, Szmacinski H, Wolfbeis OS, Terpetschnig E (1999) Synthesis, spectral properties, and detection limits of reactive squaraine dyes, a new class of diode laser compatible fluorescent protein labels. Bioconjugate Chem 10 925-931... 

Lin Y, Weissleder R, Tung CH (2002) Novel near-infrared cyanine fluorochromes synthesis, properties, and bioconjugation. Bioconjugate Chem 13 605-610... 

Li, Y. L. and Glazer, A. N. (1999). Design, synthesis, and spectroscopic properties of peptide-bridged fluorescence energy-transfer cassettes. Bioconjug. Chem. 10, 241-245. 

D. Zanini and R. Roy, Chemoenzymatic synthesis and lectin binding properties of dendritic /V-acetyllactosaniine, Bioconjug. Chem., 8 (1997) 187-192. 

Ultimately, this section is meant to function as a ready-reference database for learning or review of bioconjugate chemistry. In this regard, a reaction can be quickly found, a short discussion of its properties and use read, and a visual representation of the chemistry of bond formation illustrated. What this section is not meant to be is an exhaustive discussion on the theory or mechanism behind each reaction, nor a review of every application in which each chemical reaction has been used. For particular applications where the chemistries are employed, cross-references are given to other sections in this book or to outside literature sources. 

The advantage of the click reaction for bioconjugation is that the reactant pair is not reactive with any other functional group encountered in biological systems. This property of... 

Of all the fullerene forms, the nearly spherical properties of C o have attracted the greatest attention, especially in the field of bioconjugation. In addition to its physical properties, C o fullerenes have unique photo-optical and electro-chemical properties, which make them useful as carriers for biomedical research applications. For instance, upon exposure to light C o will generate singlet oxygen, which can be used in vivo to cleave biological molecules, particularly DNA and RNA. Studies indicate that irradiation of Cgo in solution can be used to destroy virus contamination (Kasermann and Kempf, 1997). Solutions of Buckminsterfullerene are a deep purple color, whereas other sizes of fullerenes display a variety of other colors. 

Noguchi, A., Takahashi, T., Yamaguchi, T., Kitamura, K., Takakura, Y., Hashida, M., and Sezaki, H. (1992) Preparation and properties of the immunoconjugate composed of anti-human colon cancer monoclonal antibody and mitomycin C—Dextran conjugate. Bioconjugate Chem. 3, 132-137. 

It is the responsibility of the reader to become familiar with patents that may cover particular compounds, compositions, reactions, or their use in bioconjugation applications. If patents or patent applications exist, it is important that permission or a license be obtained to use it before exploiting any intellectual property for commercial use. 

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. 

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. 

Wolfert MA, Dash PR, Nazarova O, et al. Polyelectrolyte vectors for gene delivery influence of cationic polymer on biophysical properties of complexes formed with DNA. Bioconjug Chem 1999 10(6) 993-1004. 

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