The chemicals tetraethylorthosilicate (TEOS), n-cetyltrimethylammonium bromide (CTABr), sodium hy... more The chemicals tetraethylorthosilicate (TEOS), n-cetyltrimethylammonium bromide (CTABr), sodium hydroxide (NaOH), Safranine O, (3-mercaptopropyl) trimethoxysilane, 2,2'-dipyridyl disulfide, O-(2-Mercaptoethyl)-O’-methyl-hexa(ethylene glycol), GSH and selected amino acids (Cys, Hcy, Ala, Arg, Asn, Asp, Glu, Gln, Gly, His, Thr, Trp, Tyr and Val) were provided by Sigma-Aldrich. Human serum from male AB plasma, USA origin were provided by Sigma-Aldrich. Analyticalgrade solvents were from Scharlab (Barcelona, Spain). All reagents were used as received.
The sensing behaviour toward metal cations and biothiols of two 2,4,5-triarylimidazole probes (3a... more The sensing behaviour toward metal cations and biothiols of two 2,4,5-triarylimidazole probes (3a and 3b) is tested in acetonitrile and in acetonitrile-water. In acetonitrile the two probes present charge-transfer absorption bands in the 320-350 nm interval. Among all cations tested only Cu(II) is able to induce bathochromic shifts of the absorption band in the two probes, which is reflected in marked colour changes. Colour modulations are ascribed to the formation of 1:1 Cu(II)-probe complexes in which the cation interacts with the imidazole acceptor heterocycle. Besides, the two probes present intense emission bands (at 404 and 437 nm for 3a and 3b respectively) in acetonitrile that are quenched selectively by Cu(II). Probe 3a is soluble in acetonitrile-water 1:1 (v/v) and Cu(II) also induces bathochromic shifts of the absorption bands. Moreover, the emission bands of probe 3a in this mixed aqueous solutions is quenched in the presence of Cu(II). The potential use of the 1:1 complex formed between 3a and Cu (II) for the chromo-fluorogenic detection of biothiols (GSH, Cys and Hcy) in aqueous environments is also tested. At this respect, addition of GSH, Cys and Hcy to acetonitrile-water 1:1 v/v solutions of 3a-Cu(II) complex induces a hypsochromic shift of the visible band (reflected in a bleaching of the solutions) with a marked emission increase at 470 nm.
The imidazole derivative 4-(4,5-diphenyl-1H-imidazol-2-yl)-N,N-dimethylaniline (probe 1) formed a... more The imidazole derivative 4-(4,5-diphenyl-1H-imidazol-2-yl)-N,N-dimethylaniline (probe 1) formed a highly coloured and non-emissive 1:1 stoichiometry complex with Cu(II) in water-acetonitrile 1:1 (v/v) solutions.
Cu(ii) coordination with aldehyde-containing probes induced the appearance of NIR bands coupled w... more Cu(ii) coordination with aldehyde-containing probes induced the appearance of NIR bands coupled with remarkable colour changes.
The consumption of illicit drugs has increased exponentially in recent years and has become a pro... more The consumption of illicit drugs has increased exponentially in recent years and has become a problem that worries both governments and international institutions. The rapid emergence of new compounds, their easy access, the low levels at which these substances are able to produce an effect, and their short time of permanence in the organism make it necessary to develop highly rapid, easy, sensitive, and selective methods for their detection. Currently, the most widely used methods for drug detection are based on techniques that require large measurement times, the use of sophisticated equipment, and qualified personnel. Chromo- and fluorogenic methods are an alternative to those classical procedures.
The development of easy and affordable methods for the detection of cyanide is of great significa... more The development of easy and affordable methods for the detection of cyanide is of great significance due to the high toxicity of this anion and the potential risks associated with its pollution. Herein, optical detection of cyanide in water has been achieved by using a hybrid organic-inorganic nanomaterial. Mesoporous silica nanoparticles were loaded with [Ru(bipy)3] 2+ , functionalized with macrocyclic Nickel(II) complex subunits, and capped with a sterically hindering anion (hexametaphosphate). Cyanide selectively induces demetallation of Nickel(II) complexes and the removal of capping anions from the silica surface, allowing the release of the dye and the consequent increase of fluorescence intensity. The response of the capped nanoparticles in aqueous solution is highly selective and sensitive towards cyanide with a limit of detection of 2 μM.
Mesoporous silica nanoparticles loaded with rhodamine B and capped with acetylcholinesterase are ... more Mesoporous silica nanoparticles loaded with rhodamine B and capped with acetylcholinesterase are able to be selectively opened and deliver their cargo in the presence of nerve agent simulant diisopropyl fluorophosphate (DFP).
Trivalent cations induced a dehydration reaction of a chemodosimeter in water that is coupled wit... more Trivalent cations induced a dehydration reaction of a chemodosimeter in water that is coupled with colour and emission changes.
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 19, 2016
Three different mesoporous silica nano-sized materials (SC1, SC2, and SC3), loaded with [Ru(bipy)... more Three different mesoporous silica nano-sized materials (SC1, SC2, and SC3), loaded with [Ru(bipy)3 ](2+) dye (bipy=bipyridine) and functionalized on the external surface with three macrocyclic copper(II) complexes (C1, C2, and C3), were synthesized and characterized. When SC1, SC2, and SC3 were suspended in water, the entrapped [Ru(bipy)3 ](2+) dye was free to diffuse from the inner pores to the solution. However, addition of anions induced certain degrees of pore blockage, with subsequent dye release inhibition. Small monovalent and divalent anions were unable to induce complete pore blockage, whereas bulky and highly charged anions induced marked reductions in [Ru(bipy)3 ](2+) delivery. The best [Ru(bipy)3 ](2+) delivery inhibitors were ATP and hexametaphosphate anions. Inhibition was ascribed to the interaction of the anions with the grafted Cu(II) complexes on the surface of the SC1, SC2, and SC3 supports. The hexametaphosphate anion was selected to prepare two capped materials ...
Silica nanoparticles functionalized with thiol reactive units and bulky polar polyamines were use... more Silica nanoparticles functionalized with thiol reactive units and bulky polar polyamines were used for the selective colorimetric detection of formaldehyde. The reaction of thiols groups in the nanoparticles surface with a squaraine dye resulted in loss of the π-conjugation of the chromophores, and the subsequent bleaching of the solution. However, when formaldehyde was present in the suspension, the thiol-squaraine reaction was inhibited and a chromogenic response was observed. A selective response to formaldehyde was observed only when the thiol and polyamine groups were anchored to the silica surface. The observed selective response was ascribed to the fact that bulky polyamines generate a highly polar environment around thiols, which were only able to react with the small and polar formaldehyde, but not with other aldehydes. The sensing nanoparticles showed a limit of detection (LOD) for formaldehyde of 36 ppb in water.
Synthesis and evaluation of the chromo-fluorogenic recognition ability of imidazoquinoline deriva... more Synthesis and evaluation of the chromo-fluorogenic recognition ability of imidazoquinoline derivatives toward ions, Dyes and Pigments (2015),
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 10, 2015
Cu(II) -macrocycle functionalized hexametaphosphate-capped silica mesoporous nanoparticles have b... more Cu(II) -macrocycle functionalized hexametaphosphate-capped silica mesoporous nanoparticles have been prepared and used for the selective and sensitive detection of hydrogen sulfide in aqueous environments. The possibility of using different metal complexes combined with different capping anions and choice of different dyes or other sensing molecules as indicators makes this new protocol highly appealing for the preparation of new sensing systems for sulfide detection in different environments.
Mesoporous silica nanoparticles loaded with safranin O and capped with disulfide-containing oligo... more Mesoporous silica nanoparticles loaded with safranin O and capped with disulfide-containing oligo(ethylene glycol) chains were used for the selective and sensitive fluorimetric detection of glutathione.
A new fluorescent turn-on probe for the selective detection of hydrogen sulfide in water and livi... more A new fluorescent turn-on probe for the selective detection of hydrogen sulfide in water and living cells based on a 8-hydroxyquinoline fluorophore functionalized with a 2,6-dinitrophenyl ether moiety has been developed.
The accuracy of the Content should not be relied upon and should be independently verified with p... more The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions 2,4-dinitrophenyl ether-containing chemodosimeters for the selective and sensitive 'in vitro' and 'in vivo' detection of hydrogen sulfide
A simple chemodosimeter based on a sulfonyl azide dye (1-Az), which displayed a highly selective ... more A simple chemodosimeter based on a sulfonyl azide dye (1-Az), which displayed a highly selective response toward hydrogen sulfide anion in mixed aqueous media, was synthesised and characterised. Addition of hydrogen sulfide to acetonitrile/HEPES 1:1 solutions of 1-Az induced a clear colour change from red-orange to yellow, which was easily detected by the naked eye, and by an enhancement in the emission intensity. Other common anions, thiol-containing
The chemicals tetraethylorthosilicate (TEOS), n-cetyltrimethylammonium bromide (CTABr), sodium hy... more The chemicals tetraethylorthosilicate (TEOS), n-cetyltrimethylammonium bromide (CTABr), sodium hydroxide (NaOH), Safranine O, (3-mercaptopropyl) trimethoxysilane, 2,2'-dipyridyl disulfide, O-(2-Mercaptoethyl)-O’-methyl-hexa(ethylene glycol), GSH and selected amino acids (Cys, Hcy, Ala, Arg, Asn, Asp, Glu, Gln, Gly, His, Thr, Trp, Tyr and Val) were provided by Sigma-Aldrich. Human serum from male AB plasma, USA origin were provided by Sigma-Aldrich. Analyticalgrade solvents were from Scharlab (Barcelona, Spain). All reagents were used as received.
The sensing behaviour toward metal cations and biothiols of two 2,4,5-triarylimidazole probes (3a... more The sensing behaviour toward metal cations and biothiols of two 2,4,5-triarylimidazole probes (3a and 3b) is tested in acetonitrile and in acetonitrile-water. In acetonitrile the two probes present charge-transfer absorption bands in the 320-350 nm interval. Among all cations tested only Cu(II) is able to induce bathochromic shifts of the absorption band in the two probes, which is reflected in marked colour changes. Colour modulations are ascribed to the formation of 1:1 Cu(II)-probe complexes in which the cation interacts with the imidazole acceptor heterocycle. Besides, the two probes present intense emission bands (at 404 and 437 nm for 3a and 3b respectively) in acetonitrile that are quenched selectively by Cu(II). Probe 3a is soluble in acetonitrile-water 1:1 (v/v) and Cu(II) also induces bathochromic shifts of the absorption bands. Moreover, the emission bands of probe 3a in this mixed aqueous solutions is quenched in the presence of Cu(II). The potential use of the 1:1 complex formed between 3a and Cu (II) for the chromo-fluorogenic detection of biothiols (GSH, Cys and Hcy) in aqueous environments is also tested. At this respect, addition of GSH, Cys and Hcy to acetonitrile-water 1:1 v/v solutions of 3a-Cu(II) complex induces a hypsochromic shift of the visible band (reflected in a bleaching of the solutions) with a marked emission increase at 470 nm.
The imidazole derivative 4-(4,5-diphenyl-1H-imidazol-2-yl)-N,N-dimethylaniline (probe 1) formed a... more The imidazole derivative 4-(4,5-diphenyl-1H-imidazol-2-yl)-N,N-dimethylaniline (probe 1) formed a highly coloured and non-emissive 1:1 stoichiometry complex with Cu(II) in water-acetonitrile 1:1 (v/v) solutions.
Cu(ii) coordination with aldehyde-containing probes induced the appearance of NIR bands coupled w... more Cu(ii) coordination with aldehyde-containing probes induced the appearance of NIR bands coupled with remarkable colour changes.
The consumption of illicit drugs has increased exponentially in recent years and has become a pro... more The consumption of illicit drugs has increased exponentially in recent years and has become a problem that worries both governments and international institutions. The rapid emergence of new compounds, their easy access, the low levels at which these substances are able to produce an effect, and their short time of permanence in the organism make it necessary to develop highly rapid, easy, sensitive, and selective methods for their detection. Currently, the most widely used methods for drug detection are based on techniques that require large measurement times, the use of sophisticated equipment, and qualified personnel. Chromo- and fluorogenic methods are an alternative to those classical procedures.
The development of easy and affordable methods for the detection of cyanide is of great significa... more The development of easy and affordable methods for the detection of cyanide is of great significance due to the high toxicity of this anion and the potential risks associated with its pollution. Herein, optical detection of cyanide in water has been achieved by using a hybrid organic-inorganic nanomaterial. Mesoporous silica nanoparticles were loaded with [Ru(bipy)3] 2+ , functionalized with macrocyclic Nickel(II) complex subunits, and capped with a sterically hindering anion (hexametaphosphate). Cyanide selectively induces demetallation of Nickel(II) complexes and the removal of capping anions from the silica surface, allowing the release of the dye and the consequent increase of fluorescence intensity. The response of the capped nanoparticles in aqueous solution is highly selective and sensitive towards cyanide with a limit of detection of 2 μM.
Mesoporous silica nanoparticles loaded with rhodamine B and capped with acetylcholinesterase are ... more Mesoporous silica nanoparticles loaded with rhodamine B and capped with acetylcholinesterase are able to be selectively opened and deliver their cargo in the presence of nerve agent simulant diisopropyl fluorophosphate (DFP).
Trivalent cations induced a dehydration reaction of a chemodosimeter in water that is coupled wit... more Trivalent cations induced a dehydration reaction of a chemodosimeter in water that is coupled with colour and emission changes.
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 19, 2016
Three different mesoporous silica nano-sized materials (SC1, SC2, and SC3), loaded with [Ru(bipy)... more Three different mesoporous silica nano-sized materials (SC1, SC2, and SC3), loaded with [Ru(bipy)3 ](2+) dye (bipy=bipyridine) and functionalized on the external surface with three macrocyclic copper(II) complexes (C1, C2, and C3), were synthesized and characterized. When SC1, SC2, and SC3 were suspended in water, the entrapped [Ru(bipy)3 ](2+) dye was free to diffuse from the inner pores to the solution. However, addition of anions induced certain degrees of pore blockage, with subsequent dye release inhibition. Small monovalent and divalent anions were unable to induce complete pore blockage, whereas bulky and highly charged anions induced marked reductions in [Ru(bipy)3 ](2+) delivery. The best [Ru(bipy)3 ](2+) delivery inhibitors were ATP and hexametaphosphate anions. Inhibition was ascribed to the interaction of the anions with the grafted Cu(II) complexes on the surface of the SC1, SC2, and SC3 supports. The hexametaphosphate anion was selected to prepare two capped materials ...
Silica nanoparticles functionalized with thiol reactive units and bulky polar polyamines were use... more Silica nanoparticles functionalized with thiol reactive units and bulky polar polyamines were used for the selective colorimetric detection of formaldehyde. The reaction of thiols groups in the nanoparticles surface with a squaraine dye resulted in loss of the π-conjugation of the chromophores, and the subsequent bleaching of the solution. However, when formaldehyde was present in the suspension, the thiol-squaraine reaction was inhibited and a chromogenic response was observed. A selective response to formaldehyde was observed only when the thiol and polyamine groups were anchored to the silica surface. The observed selective response was ascribed to the fact that bulky polyamines generate a highly polar environment around thiols, which were only able to react with the small and polar formaldehyde, but not with other aldehydes. The sensing nanoparticles showed a limit of detection (LOD) for formaldehyde of 36 ppb in water.
Synthesis and evaluation of the chromo-fluorogenic recognition ability of imidazoquinoline deriva... more Synthesis and evaluation of the chromo-fluorogenic recognition ability of imidazoquinoline derivatives toward ions, Dyes and Pigments (2015),
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 10, 2015
Cu(II) -macrocycle functionalized hexametaphosphate-capped silica mesoporous nanoparticles have b... more Cu(II) -macrocycle functionalized hexametaphosphate-capped silica mesoporous nanoparticles have been prepared and used for the selective and sensitive detection of hydrogen sulfide in aqueous environments. The possibility of using different metal complexes combined with different capping anions and choice of different dyes or other sensing molecules as indicators makes this new protocol highly appealing for the preparation of new sensing systems for sulfide detection in different environments.
Mesoporous silica nanoparticles loaded with safranin O and capped with disulfide-containing oligo... more Mesoporous silica nanoparticles loaded with safranin O and capped with disulfide-containing oligo(ethylene glycol) chains were used for the selective and sensitive fluorimetric detection of glutathione.
A new fluorescent turn-on probe for the selective detection of hydrogen sulfide in water and livi... more A new fluorescent turn-on probe for the selective detection of hydrogen sulfide in water and living cells based on a 8-hydroxyquinoline fluorophore functionalized with a 2,6-dinitrophenyl ether moiety has been developed.
The accuracy of the Content should not be relied upon and should be independently verified with p... more The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions 2,4-dinitrophenyl ether-containing chemodosimeters for the selective and sensitive 'in vitro' and 'in vivo' detection of hydrogen sulfide
A simple chemodosimeter based on a sulfonyl azide dye (1-Az), which displayed a highly selective ... more A simple chemodosimeter based on a sulfonyl azide dye (1-Az), which displayed a highly selective response toward hydrogen sulfide anion in mixed aqueous media, was synthesised and characterised. Addition of hydrogen sulfide to acetonitrile/HEPES 1:1 solutions of 1-Az induced a clear colour change from red-orange to yellow, which was easily detected by the naked eye, and by an enhancement in the emission intensity. Other common anions, thiol-containing
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