“Off-On” based fluorescent chemosensor for Cu2+ in aqueous media and living cells

Abstract

a b s t r a c tA novel Cu 2+ -specific "off-on" fluorescent chemosensor of naphthalimide modified rhodamine B (naphthalimide modified rhodamine B chemosensor, NRC) was designed and synthesized, based on the equilibrium between the spirolactam (non-fluorescence) and the ring-opened amide (fluorescence). The chemosensor NRC showed high Cu 2+ -selective fluorescence enhancement over commonly coexistent metal ions or anions in neutral aqueous media. The limit of detection (LOD) based on 3 × ı blank /k was obtained as low as 0.18 M of Cu 2+ , as well as an excellent linearity of 0.05-4.5 M (R = 0.999), indicating the chemosensor of high sensitivity and wide quantitation range. And also the coordination mode with 1:1 stoichiometry was proposed between NRC and Cu 2+ . In addition, the effects of pH, co-existing metal ions and anions, and the reversibility were investigated in detail. It was also demonstrated that the NRC could be used as an excellent "off-on" fluorescent chemosensor for the measurement of Cu 2+ in living cells with satisfying results, which further displayed its valuable applications in biological systems.

Ultrasensitive colorimetric detection of Cu2+ ion based on catalytic oxidation of l-cysteine

“…As seen from Table S1, methods such as ICP-MS (Wu and Boyle, 1997;Dai et al, 2012) and AAS (Chan and Huang, 2000;Lima et al, 2012) can detect Cu 2 þ ion with high sensitivity and selectivity, but they require large-scale instruments and highly trained operators restricting the practical on-site detection. The fluorometry methods also own good selectivity, but they are often troubled with complicated synthesis (Chan et al, 2010;Yu et al, 2011;Yuan et al, 2013;Zhang et al, 2013). The electrochemistry methods show low detection limit and broad linear range, but possibly with the disadvantages of instability and interference of organics in anodic/catholic stripping voltammetry (Liu et al, 1999;Salaun and van den, Berg, 2006;Lin et al, 2012).…”

“…Methods such as ICP-MS (Wu and Boyle, 1997;Dai et al, 2012) and AAS (Chan and Huang, 2000;Lima et al, 2012) can detect Cu 2 þ ion with high sensitivity and selectivity but with requirements of large instruments. Compared with electrochemical techniques (Liu et al, 1999;Salaun and van den Berg, 2006;Lin et al, 2012) and fluorescence methods (Chan et al, 2010;Yu et al, 2011;Yuan et al, 2013;Zhang et al, 2013) are much simpler with detection by naked eyes and UV-vis spectroscopy (Lou et al, 2011;Liu et al, 2013;Shen et al, 2013;Wang et al, 2014). However, till now, the reported colorimetric methods usually present higher detection limit and cannot easily accomplish real samples analysis.…”

Label-free, Water-soluble Fluorescent Peptide Probe for a Sensitive and Selective Determination of Copper Ions

“…For human beings, an excessive intake of Cu 2+ is harmful, and can cause copper-transport diseases (e.g., Wilson disease and several neurological disorders). [5][6][7][8][9] Therefore, looking for facile techniques that will enable professionals to monitor the concentration of Cu 2+ in environmental, water, and drinking water samples are of considerable significance for protecting the environment and human health. [10][11][12][13][14][15][16][17][18][19][20] A variety of techniques have been developed and used for detecting Cu 2+ at trace quantity levels in various samples.…”

A “turn-on” fluorescent and colorimetric sensor for selective detection of Cu2+ in aqueous media and living cells

“…The cellular toxicity of ionic copper can cause oxidative stress and disorders which are associated with serious neurodegenerative diseases including Menkes disease [13,14], Wilson disease [14], Alzheimer's disease [15] and prion disease [16]. Hence the sensing and recognition of Cu 2+ has attracted considerable attention in recent years, and many fluorescent sensors for copper ions have been developed [17][18][19][20][21][22][23]. Direct complexation strategy is often employed to design and develop fluorogenic probes for Cu 2+ .…”