RESUMO
A new spectrofluorimetric method was developed for determination of trace amount of bilirubin. Using oxytetracycline-Eu(3+) as a fluorescent probe, in the buffer solution of pH = 7.3, bilirubin can reduce remarkably the fluorescence intensity of the oxytetracycline-Eu(3+) complex at λ = 612 nm and the reduced fluorescence intensity was in proportion to the concentration of bilirubin. Optimum conditions for the determination of bilirubin were also investigated. The linear range and limit of detection for the determination of bilirubin were 5.0 × 10(-7) , 3.0 × 10(-5) and 7.7 × 10(-8) mol L(-1) , respectively. This method is simple, practical and relatively free of interference from coexisting substances and can be successfully applied to assess bilirubin in serum samples and compared with the modified Jendrassik-Grof method in clinical analysis. The quenching mechanism of the fluorescence intensity in the system is also discussed.
Assuntos
Bilirrubina/análise , Európio/química , Corantes Fluorescentes/química , Oxitetraciclina/química , Soro/química , Espectrometria de Fluorescência , Bilirrubina/química , HumanosRESUMO
A new spectrofluorimetric method was developed for the determination of trace amounts of histamine in human urine and serum samples. In NaAc-HAc buffer solution of pH 4.0, histamine can react with the acetylacetone-formaldehyde system to produce a fluorescent derivative which emits yellow-green fluorescence at 476 nm, according to the Hantzsch reaction, and the enhanced fluorescence intensity is in proportion to the concentration of histamine. Optimum conditions for the determination of histamine were also investigated. The dynamic range and detection limit for the determination of histamine is 5.96 x 10(-8)-1.50 x 10(-5 )mol/L and 4.35 x 10(-8)mol/L, respectively. This method is practical and can be successfully applied to determination of histamine in human urine and serum samples. A proposal of the reaction pathway is suggested.
Assuntos
Histamina/sangue , Histamina/urina , Espectrometria de Fluorescência/métodos , Fluorescência , Formaldeído/química , Humanos , Concentração de Íons de Hidrogênio , Pentanonas/química , Sensibilidade e Especificidade , Espectrometria de Fluorescência/instrumentaçãoRESUMO
Superoxide dismutase (SOD) can enhance the characteristic fluorescence of europium in europium (Eu(3+))-tetracycline (TC) system. According to this, a new spectrofluorimetric determination of SOD was developed. Under the optimum conditions, Eu(3+)-TC formed a ternary complex in close proximity with SOD and then intra-molecular energy transfer from TC-SOD complex to Eu(3+), which resulted in the enhancement of characteristic peak of Eu(3+) at 612 nm. The enhanced fluorescence intensity is in proportion to the concentration of SOD, and the linear range was 0.0553-38.71 microg mL(-1) with the limit of detection of 5.53 ng mL(-1). The developed method was practical, simple, sensitive and relatively free from interference coexisting substances and has been successfully applied to the determination of SOD in the plant and blood samples. The mechanism of fluorescence enhancement between Eu(3+)-TC complex and SOD was also studied.
Assuntos
Európio/metabolismo , Sondas Moleculares/metabolismo , Superóxido Dismutase/análise , Tetraciclina/metabolismo , Animais , Alho/enzimologia , Humanos , Indicadores e Reagentes , Espectrometria de Fluorescência , Superóxido Dismutase/sangue , Suínos , Fatores de TempoRESUMO
A new fluorescent reagent 1,5-bis(4,6-dichloro-1,3,5-triazinylamino)naphthalene (DTAN) was synthesized. The optimum conditions of fluorescent reaction of this reagent with aniline (PA) were also investigated. Based on this reaction, a new spectrofluorimetric method was developed for the determination of aniline. The fluorescent intensity was directly proportional to the concentration of aniline in the ranges 0.05-2.0 microg mL(-1) and 2.0-50 microg mL(-1) with the detection limits of 34 ng mL(-1) and 90 ng mL(-1). This method is simple, practical and can afford good precision and accuracy and can be successfully applied to assess aniline in water samples. A possible mechanism of the change of fluorescence intensity introduced by putting the aniline into the system is also discussed.
Assuntos
1-Naftilamina/análogos & derivados , Compostos de Anilina/análise , Triazinas/síntese química , 1-Naftilamina/síntese química , 1-Naftilamina/química , Concentração de Íons de Hidrogênio , Esgotos/química , Espectrometria de Fluorescência , Temperatura , Fatores de Tempo , Triazinas/química , Água/químicaRESUMO
A new fluorescent reagent, 1,5-bis(4,6-dichloro-1,3,5-triazinylamino)naphthalene, containing two active chlorines, was synthesized by a one-step reaction. Under the optimum conditions for the determination of dopamine, the enhanced fluorescence intensity is proportional to the dopamine concentration. The fluorescence intensity was measured at lambda(ex/em) = 400/460 nm, with and without dopamine. The linear range and detection limit for the determination of dopamine were 1.0 x 10(-7) mol/L-5.0 x 10(-5) mol/L and 4.0 x 10(-8) mol/L. This method is simple, practical, can afford good precision and accuracy and can be successfully applied to assess dopamine in injections and human serum samples.
Assuntos
1-Naftilamina/análogos & derivados , Dopamina/sangue , Corantes Fluorescentes/síntese química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Triazinas/síntese química , 1-Naftilamina/síntese química , Humanos , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
A new spectrofluorimetric method was developed for the determination of trace amounts of dopamine (DA). Using chlorosulfonylthenoyltrifluoroacetone (CTTA)-europium ion (Eu(3+)) as a fluorescent probe, in a buffer solution at pH = 10.0, DA can remarkably enhance the fluorescence intensity of the CTTA-Eu(3+) complex at lambda = 612 nm; the enhanced fluorescence intensity of Eu(3+) is proportional to the concentration of DA. Optimum conditions for the determination of DA were also investigated. The linear range and detection limit for the determination of DA were 5.0 x 10(-8) approximately 1.6 x 10(-5) mol/l and 3.2 x 10(-8) mol/l. This method is simple, practical and relatively free of interference from coexisting substances, and can be applied to assess DA in injection and human serum samples with good precision and accuracy.
Assuntos
Dopamina/análise , Espectrometria de Fluorescência/métodos , Análise Química do Sangue/métodos , Dopamina/sangue , Európio , Corantes Fluorescentes , Humanos , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Tensoativos , Temperatura , Tenoiltrifluoracetona/análogos & derivadosRESUMO
A new spectrofluorimetric method was developed for the determination of trace amounts of bile acid (BA). Using europium ion (Eu(3+))-doxycycline (DC) as a fluorescent probe, in a buffer solution of pH=7.0, BA can remarkably reduce the fluorescence intensity of the DC-Eu(3+) complex at lambda=612 nm; the reduced fluorescence intensity of the Eu(3+) is proportional to the concentration of BA. Optimum conditions for the determination of BA were also investigated. The linear range and detection limit for the determination of BA were 5.0 x 10(-8) mol/L to 5.5 x 10(-7) mol/L and 1.1 x 10(-8) mol/L, respectively. This method is practical and relatively free of interference from coexisting substances, and can be successfully applied to assess BA in serum samples.
Assuntos
Ácidos e Sais Biliares/sangue , Técnicas de Laboratório Clínico , Európio , Compostos Organometálicos/química , Tetraciclinas/química , Humanos , Espectrometria de FluorescênciaRESUMO
A new spectrofluorimetric method was developed for the determination of trace amounts of 5-hydroxytryptamine (5-HT). Using chlorosulphonylthenoyltrifluoroacetone (CTTA)-europium (Eu(3+)) ion as a fluorescent probe in a buffer solution at pH 11.0, 5-HT can remarkably enhance the fluorescence intensity of the CTTA-Eu(3+) complex at lambda = 612 nm; the enhanced fluorescence intensity of Eu(3+) is proportional to the concentration of 5-HT. Optimum conditions for the determination of 5-HT were also investigated. The linear range and detection limit for the determination of 5-HT were 1.0 x 10(-7)-1.2 x 10(-5) mol/L and 8.5 x 10(-8) mol/L, respectively. This method is simple, practical and relatively free of interference from coexisting substances, and can be applied to assess 5-HT in urine samples.
Assuntos
Európio/química , Corantes Fluorescentes/química , Compostos Organometálicos/química , Serotonina/análise , Tenoiltrifluoracetona/análogos & derivados , Tenoiltrifluoracetona/química , Aminoácidos/química , Humanos , Concentração de Íons de Hidrogênio , Metais/química , Valores de Referência , Sensibilidade e Especificidade , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos , Tensoativos/química , Temperatura , Fatores de TempoRESUMO
A new spectrofluorometric method has been developed for the determination of trace amounts of coenzyme A (CoA). Using europium (Eu3+)-tetracycline (TC) complex as a fluorescent probe in the buffer solution of pH 6.80, CoA could remarkably enhance the fluorescence intensity of the Eu3+-TC complex at lambda = 612 nm after adding H(5)IO(6) and the enhanced fluorescence intensity is in proportion to the concentration of CoA. Optimum conditions for the determination of CoA were also investigated. The dynamic range for the determination of CoA is 6.08 x 10(-8) - 1.84 x 10(-5) mol L(-1) with detection limit of 4.62 x 10(-8) mol L(-1). This method is simple, practical and relatively free of interference from coexisting substances and can be successfully applied to determination of CoA in injection, human serum and pig liver samples. Moreover, the enhancement mechanisms of the fluorescence intensity in the Eu3+-TC system and the CoA-Eu3+-TC system have been also discussed.
Assuntos
Coenzima A/análise , Coenzima A/sangue , Fígado/química , Espectrometria de Fluorescência/instrumentação , Suínos , Animais , Coenzima A/química , Európio/química , Humanos , Concentração de Íons de Hidrogênio , Espectrometria de Fluorescência/métodos , Espectrofotometria Atômica , Tetraciclina/químicaRESUMO
A new spectrofluorimetric method was developed for the determination of trace amount of 5-hydroxytryptamine (5-HT) in human urine and serum samples. In the NaAc-HAc buffer solution of pH=5.80, 5-HT can react with formaldehyde-acetylacetone system to form a new compound which sends yellow green fluorescence at 533 nm and the enhanced fluorescence intensity is in proportion to the concentration of 5-HT. Optimum conditions for the determination of 5-HT were also investigated. The dynamic range and detection limit for the determination of 5-HT are 5.35 x 10(-7) approximately 1.07 x 10(-4) mol/L and 2.08 x 10(-7) mol/L, respectively. The developed method is simple, practical and can be successfully applied to determination of 5-HT in human urine and serum samples. Moreover, the enhancement mechanisms of the fluorescence intensity in the 5-HT - formaldehyde-acetylacetone system have been also discussed.
Assuntos
Serotonina/sangue , Serotonina/urina , Espectrometria de Fluorescência/métodos , Calibragem , Formaldeído/química , Humanos , Concentração de Íons de Hidrogênio , Estrutura Molecular , Pentanonas/química , Reprodutibilidade dos Testes , Serotonina/químicaRESUMO
A new spectrofluorimetric method was developed for the determination of trace amounts of coenzyme A (CoA). In the presence of periodic acid (H5IO6), CoA can remarkably enhance the fluorescence intensity of the Tb3+-ciprofloxacin (CIP) complex at 545 nm in a buffer solution at pH 5.4; the enhanced fluorescence intensity of the Tb3+ ion is proportional to the concentration of CoA. The optimal conditions for the determination of CoA were also investigated. The linear range and the detection limit for the determination of CoA were 6.08x10(-6)-1.64x10(-5) and 2.1x10(-8) mol L-1, respectively. This method is simple, practical and relatively free of interference from coexisting substances, and can be successfully applied to assess CoA in injection and biological samples. Moreover, the enhancement mechanism of the fluorescence intensity of the CoA-Tb3+-CIP system in the presence of H5IO6 is also discussed.
Assuntos
Ciprofloxacina/química , Coenzima A/análise , Íons/química , Ácido Periódico , Espectrometria de Fluorescência/métodos , Térbio/análise , Animais , Coenzima A/química , Coenzima A/metabolismo , Concentração de Íons de Hidrogênio , Fígado/metabolismo , Estrutura Molecular , Suínos , Térbio/química , Fatores de TempoRESUMO
BACKGROUND: Alkaline phosphatase (ALP) is an important target for clinical analysis. 8-Quinolyl phosphate (QP) was developed as a new substrate for the fluorimetric determination of ALP activity. METHODS: QP is a strong fluorescent substance and the product of the enzyme reaction is 8-hydroxyquinoline (HQ), which has no fluorescence. Under the optimal conditions for the determination of ALP, the decreased fluorescence intensity via the enzyme reaction is proportional to ALP activity. The fluorescence intensity was measured at lambdaex/lambdaem=318/495 nm before and after the enzyme reaction. RESULTS: QP reacted with ALP in the buffer solution of pH=9.5 and incubated for 20 min at 37.0 degrees C were selected as the optimal conditions for the determination of ALP. The linear range and detection limit for the determination of ALP are 1.0-16.0 and 0.229 U/l, respectively. With this method, ALP could be applied to assess ALP in human serum and the results were evaluated by comparison with a standard colorimetric assay using p-nitrophenyl phosphate as ALP substrate. CONCLUSIONS: This method is simple, practical and can be used as an alternative to assess ALP in clinical analysis.
Assuntos
Fosfatase Alcalina/análise , Fosfatase Alcalina/metabolismo , Organofosfatos/metabolismo , Quinolinas/metabolismo , Fluorometria , Fatores de Troca do Nucleotídeo Guanina , Humanos , Concentração de Íons de Hidrogênio , Estrutura Molecular , Organofosfatos/química , Proteínas Proto-Oncogênicas , Quinolinas/química , Fatores de Troca de Nucleotídeo Guanina Rho , Especificidade por Substrato , TemperaturaRESUMO
A new fluorescent reagent, 2-hydroxy-1-naphthaldehydene-8-aminoquinoline (HNAAQ), was synthesized. The fluorescent reaction of this reagent with mercury was also studied. Based on this chelation, a highly sensitive spectrofluorometric method was developed for the determination of trace amounts of mercury in a water-ethanol (5 + 1, v/v) medium at pH 8.0. Under these conditions, the Hg-HNAAQ complex has excitation and emission maxima at 406 and 445 nm, respectively. The linear range of the method is from 0 to 16 microg L(-1) and the detection limit is 0.056 microg L(-1) of mercury. The interference of other ions was studied. In order to enhance the selectivity in the determination of mercury by the present method, we also applied the separation of mercury by distillation. Thus, the selectivity of the method could be increased remarkably. The procedure can be easily performed, and affords good precision and accuracy. This method has been successfully applied to the determination of mercury in waste water and prawns.
RESUMO
A new spectrofluorimetric method was developed for the determination of trace amounts of lecithin using the ciprofloxacin (CIP)-terbium (Tb3+) ion complex as a fluorescent probe. In a buffer solution at pH = 5.60, lecithin can remarkably reduce the fluorescence intensity of the CIP-Tb3+ complex at lambda = 545 nm. The reduced fluorescence intensity of the Tb3+ ion is proportional to the concentration of lecithin. Optimum conditions for the determination of lecithin were also investigated. The linear range and detection limit for the determination of lecithin were 1.0 x 10(-6) - 3.0 x 10(-5) mol L(-1) and 3.44 x 10(-7) mol L(-1), respectively. This method is simple, practical, and relatively free of interference from coexisting substances. Furthermore, it has been successfully applied to assess lecithin in serum samples.
Assuntos
Fosfatidilcolinas/análise , Fosfatidilcolinas/química , Espectrometria de Fluorescência/métodos , Concentração de Íons de Hidrogênio , Sensibilidade e Especificidade , Térbio/química , Fatores de TempoRESUMO
BACKGROUND: Lecithin is found throughout biological systems. A new spectrofluorimetric method was developed for the determination of trace amounts of lecithin. METHODS: Optimum conditions for the determination of lecithin were investigated. RESULTS: Using norfloxacin (NF)-terbium ion (Tb3+) as a fluorescent probe, in a buffer solution at pH=6.80, lecithin reduced the fluorescence intensity of the NF-Tb3+ complex at lambda=545 nm; the reduced fluorescence intensity of the Tb3+ ion is proportional to the concentration of lecithin. The linear range and detection limit for the determination of lecithin were 1.08 x 10(-6)-3.02 x 10(-5) mol/l and 2.54 x 10(-7) mol/l. CONCLUSION: This method is simple, practical and relatively free of interference from coexisting substances, and can be successfully applied to assess lecithin in serum samples.
Assuntos
Norfloxacino/sangue , Fosfatidilcolinas/sangue , Fosfatidilcolinas/química , Térbio/sangue , Cátions/química , Corantes Fluorescentes/análise , Corantes Fluorescentes/química , Concentração de Íons de Hidrogênio , Norfloxacino/química , Fosfatidilcolinas/biossíntese , Sensibilidade e Especificidade , Espectrometria de Fluorescência , Térbio/química , Fatores de TempoRESUMO
A new spectrofluorimetric method was developed for determination of trace amount of heparin (Hep). Using lomefloxacin (LOM)-terbium ion (Tb3+) as a fluorescent probe, in the buffer solution of pH 8.70, Hep can remarkably enhance the fluorescence intensity of the LOM-Tb3+ complex at lambda = 545 nm and the enhanced fluorescence intensity of Tb3+ ion is in proportion to the concentration of Hep. Optimum conditions for the determination of Hep were also investigated. The linear range for the determination of Hep was 0.6-2.0 microg/ml and the detection limit was 45.22 ng/ml. This method is simple, practical and relatively free of interference from coexisting substances and can be successfully applied to assess Hep in biological samples. By the Rosenthanl graphic method, the association constant of Hep with the probe is 4.56 x 10(4) l/mol and binding numbers is 18.2. Moreover, the enhancement mechanism of the fluorescence intensity in the LOM-Tb3+ system and the LOM-Tb3+-Hep system have also been discussed.
Assuntos
Corantes Fluorescentes/análise , Fluoroquinolonas/química , Heparina/análise , Quinolonas/química , Térbio/química , Corantes Fluorescentes/química , Heparina/sangue , Heparina/química , Humanos , Concentração de Íons de Hidrogênio , Injeções , Espectrometria de Fluorescência , Fatores de TempoRESUMO
A new spectrofluorimetric method was developed for determination of trace amount of Coenzyme II (NADP). Using europium ion-doxycycline (DC) as a fluorescent probe, in the buffer solution of pH 8.44, NADP can remarkably enhance the fluorescence intensity of the Eu(3+)-DC complex at lambda=612 nm and the enhanced fluorescence intensity is in proportion to the concentration of NADP. Optimum conditions for the determination of NADP were also investigated. The dynamic range for the determination of NADP is 3.3 x 10(-7) to 6.1 x 10(-6) mol l(-1) with detection limit of 6.8 x 10(-8) mol l(-1). This method is simple, practical and relatively free interference from coexisting substances and can be successfully applied to determination of NADP in synthetic water samples and in serum samples. Moreover, the enhancement mechanisms of the fluorescence intensity in the Eu(3+)-DC system and the Eu(3+)-DC-NADP system have been also discussed.
Assuntos
Doxiciclina/química , Európio/química , Indicadores e Reagentes/química , NADP/química , Espectrometria de Fluorescência/métodos , Humanos , Concentração de Íons de Hidrogênio , NADP/sangue , Fatores de Tempo , Água/análiseRESUMO
A new spectrofluorometric method was developed for the determination of trace amounts of heparin (Hep). Using ciprofloxacin (CIP)-terbium (Tb3+) as a fluorescent probe, in a buffer solution of pH 7.20, Hep can remarkably enhance the fluorescence intensity of the CIP-Tb3+ complex at lambda = 545 nm; also, the enhanced fluorescence intensity the Tb3+ ion is proportional to the concentration of Hep. The optimum conditions for the determination of Hep were also investigated. The dynamic range for the determination of Hep is 0.1 - 1.2 microg ml(-1) with a detection limit of 6.89 ng ml(-1). This method is simple, practical and relatively free of interference from coexisting substances, and can be successfully applied to assess Hep in biological samples. By the Rosenthanl graphic method, the association constant and binding numbers of heparin with the probe are 2.44 x 10(5) l mol(-1) and 19.7. Moreover, the enhancement mechanisms of the fluorescence intensity in the CIP-Tb3+ system and the CIP-Tb3+-Hep system have also been considered.
Assuntos
Ciprofloxacina/química , Corantes Fluorescentes/química , Heparina/análise , Térbio/química , Ciprofloxacina/metabolismo , Sensibilidade e Especificidade , Térbio/metabolismoRESUMO
A new spectrofluorimetric method was developed for determination of adenosine disodium triphosphate (ATP). We studied the interactions between oxytetracycline (OTC)-Eu3+ complex and adenosine disodium triphosphate (ATP) by using UV-vis absorption and fluorescence spectra. Using oxytetracycline (OTC)-Eu3+ as a fluorescence probe, under the optimum conditions, ATP can remarkably enhance the fluorescence intensity of the OTC-Eu3+ complex at lambda = 612 nm and the enhanced fluorescence intensity of Eu3+ ion is in proportion to the concentration of ATP. Optimum conditions for the determination of ATP were also investigated. The linear ranges for ATP are 8.00 x 10(-8)-1.50 x 10(-6) mol L(-1) with detection limits of 2.67 x 10(-9) mol L(-1). This method is simple, practical and relatively free interference from coexisting substances and can be successfully applied to determination of ATP in samples. The mechanism of fluorescence enhancement between oxytetracycline (OTC)-Eu3+ complex and ATP was also studied.
Assuntos
Trifosfato de Adenosina/química , Európio/química , Oxitetraciclina/química , Espectrometria de Fluorescência/métodos , Cátions/química , Corantes Fluorescentes/química , Concentração de Íons de Hidrogênio , Fatores de TempoRESUMO
A highly sensitive spectrofluorimetric method is proposed for determination of human serum albumin (HSA) and some quinolone drugs. Using quinolones-terbium (Tb3+) complex as a fluorescent probe, in the buffer solution of pH 7.8, HSA can remarkably enhance the fluorescence intensity of the quinolones-Tb3+ complex at 545 nm and the enhanced fluorescence intensity of Tb3+ ion is in proportion to the concentration of HSA and quinolone drugs. Optimum conditions for the determination of HSA were also investigated. The linear ranges and limits of detection are 8.0 x 10(-9) to 8.0 x 10(-8) mol L(-1), 4.20 x 10(-9) mol L(-1) (for HSA); 1.0 x 10(-6) to 4.0 x 10(-6) mol L(-1), 1.87 x 10(-8) mol L(-1) (for norfloxacin) and 1.0 x 10(-7) to 1.0 x 10(-6) mol L(-1), 4.82 x 10(-8) mol L(-1) (for enoxacine), respectively. This method is simple, practical and relatively free interference from coexisting substances, as well as much more sensitive than most of the existing assays.