Communication
ChemComm
with different sialylation degrees. The boronolectin 1 performs
excellent recognition of glycosylated structures within cultured
cells both under fixed and in vivo conditions preserving cell
viability. The versatility of the synthesis is compatible with
orthogonal functionalization methodologies envisioning the
immobilization of the probe in surfaces or nanostructures.
To our knowledge, our probe shows the longest fluorescent
emission reported upon sugar interaction with a maximum at
820 nm following excitation at 720 nm or 637 nm with a sensitive
signal in aqueous medium avoiding the use of co-solvents
and yielding a truly fluorogenic response. This outstanding
NIR-boronolectin is a candidate probe to detect glycan abun-
dance in cells or tissues, among other bioanalytical applications.
This work was supported by CONICET (PIP 11420100100002),
ANPCyT (PICT 2010-0362, PICT 2008-1941, PICT 2010-2817) and
UBA (20020100100465). CSL and MALH are PhD fellows from
CONICET. MLU, FCL and CCS are staff members of CONICET.
Notes and references
Fig. 4 MCF-10 cells incubated with: (A) probe 1 (50 mM) and DAPI: exc
637 nm (left), merged image (middle), DIC image (right); (B) pre-incubated
with boroxole 50 mM then with probe 1 (50 mM) and DAPI: exc 637 nm
(left), merged image (middle), DIC image (right); (C) incubated with probe 1
(50 mM), washed and then with ER-tracker Blue-white DPX (1 mM): exc
405 nm (left), 637 nm (middle), merged image (right). For all images:
incubation time 30 min, 37 1C, at pH 4 (acetate buffer).
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Chem. Commun.
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