Bioconjugated lanthanide luminescent helicates as multilabels for lab-on-a-chip detection of cancer biomarkersElectronic supplementary information (ESI) available: formula of Eu-W8044 (Fig. S1), follow-up and optimization of the bioconjugation reaction (Fig. S2–S4, Table S1), crystal-field sublevels (Table S2), relative emission intensities (Table S3), immunoluminescence assays (Fig. S5, S6). See DOI: 10.1039/b922124g

Autor:	Vanesa Fernández-Moreira, Bo Song, Venkataragavalu Sivagnanam, Anne-Sophie Chauvin, Caroline D. B. Vandevyver, Martin Gijs, Ilkka Hemmilä, Hans-Anton Lehr, Jean-Claude G. Bünzli
Předmět:	BIOCONJUGATES RARE earth metals LUMINESCENCE TUMOR markers BIOCHIPS MATRIX-assisted laser desorption-ionization TIME-of-flight mass spectrometry CANCER cells
Zdroj:	Analyst; Jan2010, Vol. 135 Issue 1, p42-52, 11p
Abstrakt:	The lanthanide binuclear helicate [Eu2(LC2(CO2H))3] is coupled to avidin to yield a luminescent bioconjugate EuB1(Q= 9.3%, τ(5D0) = 2.17 ms). MALDI/TOF mass spectrometry confirms the covalent binding of the Eu chelate and UV-visible spectroscopy allows one to determine a luminophore/protein ratio equal to 3.2. Bio-affinity assays involving the recognition of a mucin-like protein expressed on human breast cancer MCF-7 cells by a biotinylated monoclonal antibody 5D10 to which EuB1is attached viaavidin-biotin coupling demonstrate that (i) avidin activity is little affected by the coupling reaction and (ii) detection limits obtained by time-resolved (TR) luminescence with EuB1and a commercial Eu-avidin conjugate are one order of magnitude lower than those of an organic conjugate (FITC-streptavidin). In the second part of the paper, conditions for growing MCF-7 cells in 100–200 µm wide microchannels engraved in PDMS are established; we demonstrate that EuB1can be applied as effectively on this lab-on-a-chip device for the detection of tumour-associated antigens as on MCF-7 cells grown in normal culture vials. In order to exploit the versatility of the ligand used for self-assembling [Ln2(LC2(CO2H))3] helicates, which sensitizes the luminescence of both Euiiiand Tbiiiions, a dual on-chip assay is proposed in which estrogen receptors (ERs) and human epidermal growth factor receptors (Her2/neu) can be simultaneously detected on human breast cancer tissue sections. The Ln helicates are coupled to two secondary antibodies: ERs are visualized by red-emitting EuB4using goat anti-mouse IgG and Her2/neureceptors by green-emitting TbB5using goat anti-rabbit IgG. The fact that the assay is more than 6 times faster and requires 5 times less reactants than conventional immunohistochemical assays provides essential advantages over conventional immunohistochemistry for future clinical biomarker detection. [ABSTRACT FROM AUTHOR]
Databáze:	Complementary Index
Externí odkaz:	Zobrazit plný text záznamu