Fluorescent bioconjugates

The isothiocyanate derivatives of DTT-4,4-dioxide 83 <2002CEJ5072> have been found to give chemically very stable fluorescent bioconjugates to be potentially used for fluorescent markers for biopolymers... 

X. Zhao, R. Tapec-Dytioco, and W. Tan, Ultrasensitive DNA detection using highly fluorescent bioconjugated nanoparticles. J. Am. Chem. Soc. 125, 11474-11475 (2003). 

As discussed in Chapter 3.1.1, reactive cyanine dye derivatives are ideal fluorescent labels for tumour-specific carriers or vehicles, such as antibodies, proteins and peptides. In the literature, a variety of approaches can be found, where such dyes were employed in the design of fluorescent bioconjugates with enhanced selectivity for tumour-associated antigens. 

Fluorescent bioconjugates were prepared by in situ incorporation of the fluorescent probe during the synthesis of the polymer by copolymerization of fluorescent monomers with polyfethylene glycol) methyl ether methacrylate (PEGMA475) or with dimethyl aminoethyl methacrylate (DMAEMA). Both the hostasol methacrylate monomer (/<5) and novel fluorescent methacrylate monomer derived from rhodamine B (Scheme 1) were employed. 

With both copolymerized fluorescent monomers the obtained fluorescent bioconjugates could be detected by SECrHPLC with fluorescence detection (at appropriate and for each fluorescent monomer) (Figure 5). This confirmed that the fluorescent probes had been incorporated in situ into the synthetic polymer-protein conjugate during the polymerization. In addition, SEC-FL-HPLC analysis revealed the absence of unreacted fluorescent monomers in the bioconjugate samples. 

Scheme 3. Synthesis of the lysozyme fluorescent bioconjugate by living radical polymerization.

Zhao, X., Tapec-Dytioco, R. and Tan, W. (2003) Ultrasensitive DNA detection using highly fluorescent bioconjugated nanopartides. Journal of the American Chemical Society, 125,11474-5. 

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