Synthesis and cell localization of self-assembled dinuclear lanthanide bioprobes.

Lanthanide bioprobes and bioconjugates are ideal luminescent stains in view of their low propensity to photobleaching, sharp emission lines and long excited state lifetimes permitting time-resolved detection for enhanced sensitivity. In this paper, we expand our previous work which demonstrated that self-assembled dinuclear triple-stranded helicates [Ln2(L(C2X))3] behave as excellent cell and tissue labels in immunocytochemical and immunohistochemical assays. The synthetic strategy of the hexadentate ditopic ligands incorporating dipicolinic acid, benzimidazole units and polyoxyethylene pendants is revisited in order to provide a more straightforward route and to give access to further functionalization of the polyoxyethylene arms by incorporating a terminal function X.

Selective breast cancer cell capture, culture, and immunocytochemical analysis using self-assembled magnetic bead patterns in a microfluidic chip.

Separation and subsequent culturing of MCF-7 breast cancer cells on self-assembled protein-coated magnetic beads in a microfluidic chip is demonstrated. The beads were patterned in situ inside a sealed microfluidic channel using magnetic-field-assisted electrostatic self-assembly. Hereafter, they were grafted by exposure to a solution of 5D10 monoclonal antibodies (mAb) and fibronectin (FN), with the first being used for immunospecific cell capture and the latter being used for cell adhesion and growth.

Bioconjugated lanthanide luminescent helicates as multilabels for lab-on-a-chip detection of cancer biomarkers.

The lanthanide binuclear helicate [Eu(2)(L(C2(CO(2)H)))(3)] is coupled to avidin to yield a luminescent bioconjugate EuB1 (Q = 9.3%, tau((5)D(0)) = 2.17 ms).

Monolithic silicon chip for immunofluorescence detection on single magnetic beads.

While fluorescence detection is widely used for bioassays owing to its high sensitivity, a complete fluorescent microscopy setup, comprised of a light source, optical filters, a microscope body, and a camera, still is bulky equipment, compromising its use in a point-of-care environment. Here we propose an integrated monolithic silicon chip for integrated magnetic manipulation and optical detection of fluorescently labeled magnetic beads. Our approach permits microscopeless measurement of the fluorescence of a single microparticle.

Time-resolved lanthanide luminescence for lab-on-a-chip detection of biomarkers on cancerous tissues.

PDMS-based microfluidic devices combined with lanthanide-based immunocomplexes have been successfully tested for the multiplex detection of biomarkers on cancerous tissues, revealing an enhanced sensitivity compared to classical organic dyes.