For remote Hg2+ detection, an array of nanotips was covalently functionalised using a versatile photochemical approach. After chemical etching of an optical fiber bundle to generate the nanotip array, a protected n-propyl amine was grafted onto the tip surface by silanisation and thereafter photodeprotected by irradiation at 365 nm. The new rhodamine-based probe 9 developed for detection of Hg2+ was linked to the liberated amino group using the HOBt/DCC protocol. The optical fiber bundles functionalised with 9 exhibited a high selectivity toward Hg2+in situ, in full analogy to its precursor 4 in solution. Titration of the functionalised optical fiber bundles using a remote detection mode showed a detection range from 10−5 to 5 × 10−3 M for mercury ions in aqueous medium.
A highly selective and sensitive fluorescent probe for Hg2+ imaging in live cells based on a rhodamine–thioamide–alkyne scaffold
作者:Weiying Lin、Xiaowei Cao、Yundi Ding、Lin Yuan、Lingliang Long
DOI:10.1039/b927373e
日期:——
A new fluorescence turn-on probe for Hg2+ imaging in living cells was judiciously designed based on the interactions of Hg2+ to both thiol and alkyne moieties in a rhodamine scaffold, and the likely novel sensing mechanism has been proposed.
A novel on/off fluorescent rhodamine-based hexapodal Fe3+ probe (L) containing a cyclotriphosphazene core was synthesized by an azide-alkyne "click-reaction". The synthesized compounds (1-5 and L) were characterized by FT-IR; H-1, C-13, and P-31 NMR; and MALDI MS spectrometry. The optical sensor features for the Fe3+ complex of L were investigated by UV-vis and fluorescence spectroscopy. The stoichiometry of L-Fe3+ complex was found to be 1:3 (ligand/metal ion), and the detection limit of L was determined as 4.8 mu M (0.27 mg L-1) for Fe3+ ions. The reusability of the sensor was tested by the addition of ethylenediamine to L-Fe3+ complex solutions followed by the addition of Fe3+ solution.