Determination of free cholesterol based on a novel flow‐injection chemiluminescence method by immobilizing enzyme

Hu, Yufei; Zhang, Zhujun

doi:10.1002/bio.1042

Cited by 22 publications

(15 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…17%) when in the concentration of 0.01 mg L -1 , the interference was not observed in the analysis of real samples, according to the results presented in the next section. This agreed with previous studies, 32 in which the catalytic effect of zinc on the luminol oxidation was not observed in the presence of excess of another catalyst as employed in this work. Other species did not cause any interference on the determination of cholesterol.…”

Section: Effect Of Concomitant Speciessupporting

confidence: 83%

A multicommuted flow procedure for the determination of total and free cholesterol in eggs and human blood serum by chemiluminescence

Leite¹,

Vieira²,

Fatibello‐Filho³

et al. 2010

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

Um sistema de análises em fluxo com multicomutação com detecção por quimiluminescência foi desenvolvido para a determinação de colesterol livre e total sem alterações no módulo de análises. Colesterol estearase e colesterol oxidase foram imobilizadas em esferas de vidro via glutaraldeído/3-aminopropiletoxisilano e mini-colunas contendo as enzimas foram usadas para tratamento das amostras em linha. Ésteres de colesterol foram clivados a colesterol e ácidos graxos na coluna empacotada com colesterol estearase. No reator contendo colesterol oxidase, o analito foi convertido a 4-colesten-3-ona e peróxido de hidrogênio. A detecção foi baseada na quimiluminescência produzida por H 2 O 2 no sistema hexacianoferrato(III)-luminol. Os efeitos de variáveis químicas e hidrodinâmicas sobre o sinal de quimiluminescência foram avaliados. As curvas analíticas foram lineares entre 250 e 2500 mg L -1 e 500 e 4000 mg L -1 , para colesterol livre e total, respectivamente. Limites de detecção para ambos os analitos foram estimados em 60 mg L -1 (99,7% de confiança). A frequência de amostragem foi de 55 h -1 e o consumo de reagentes foi de 350 mg de luminol e 2,6 mg de hexacianoferrato(III) de potássio por determinação. O procedimento desenvolvido foi aplicado à determinação de colesterol em ovos e soro sanguíneo humano gerando resultados concordantes com o procedimento espectrofotométrico de referência com nível de confiança de 95%.A multicommuted flow-based procedure with detection by chemiluminescence for the determination of total and free cholesterol without changes in the flow manifold is proposed. Cholesterol esterase and cholesterol oxidase were both immobilized on glass beads via glutaraldehyde/(3-aminopropyl)-triethoxysilane and mini-columns containing the enzymes were used for online sample treatment. Cholesterol esters were cleaved to cholesterol and fatty acids at the packed reactor containing cholesterol esterase. The reactor containing cholesterol oxidase converted cholesterol to cholest-4-en-3-one also yielding hydrogen peroxide. Detection was based on the chemiluminescence produced by H 2 O 2 in the hexacyanoferrate(III)-luminol system. Influence of both chemical and hydrodynamic variables on the chemiluminescence signals were investigated. The analytical curves were linear from 250 to 2500 mg L -1 and from 500 to 4000 mg L -1 , for free and total cholesterol, respectively. Detection limits for both analytes were estimated as 60 mg L -1 at 99.7% confidence level. The sampling rate was 55 h -1 and reagent consumption was 350 mg of luminol and 2.6 mg of potassium hexacyanoferrate(III) per determination. The procedure developed was successfully applied for determination of cholesterol in eggs and in human blood serum with results in agreement with the reference spectrophotometric method at the 95% confidence level.

show abstract

Section: Effect Of Concomitant Speciessupporting

confidence: 83%

A multicommuted flow procedure for the determination of total and free cholesterol in eggs and human blood serum by chemiluminescence

Leite¹,

Vieira²,

Fatibello‐Filho³

et al. 2010

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

show abstract

“…For example, when using alcohol oxidase, we will detect the blood alcohol concentration. The use of ascorbate oxidase will detect the ascorbate concentration in foods; the use of cholesterol oxidase will detect the blood cholesterol concentration for medical checkup; the use of choline oxidase will detect the blood choline concentration for mental condition check; and the use of pyruvate oxidase will detect the blood pyruvate concentration for freshness check of preserved blood [1]–[3], [6]. The second one is that our method will contribute to facilitate medical and biological researches at a single-cell level.…”

Section: Discussionmentioning

confidence: 99%

“…Because these effects are dependent on the cellular level of H 2 O 2 , the measurement of low concentration of H 2 O 2 is important for the study on the association of H 2 O 2 with diseases. In addition, because H 2 O 2 is generated by an oxidase-mediated reaction, its determination is a basis for the assay of various oxidases and their substrates such as glucose, lactate, glutamate, urate, xanthine, choline, cholesterol and NADPH [1]–[3], [6].…”

Section: Introductionmentioning

confidence: 99%

Highly Sensitive Determination of Hydrogen Peroxide and Glucose by Fluorescence Correlation Spectroscopy

Watabe¹,

Sakamoto

Morikawa

et al. 2011

PLoS ONE

View full text Add to dashboard Cite

BackgroundBecause H2O2 is generated by various oxidase-catalyzed reactions, a highly sensitive determination method of H2O2 is applicable to measurements of low levels of various oxidases and their substrates such as glucose, lactate, glutamate, urate, xanthine, choline, cholesterol and NADPH. We propose herein a new, highly sensitive method for the measurement of H2O2 and glucose using fluorescence correlation spectroscopy (FCS).Methodology/Principal FindingsFCS has the advantage of allowing us to determine the number of fluorescent molecules. FCS measures the fluctuations in fluorescence intensity caused by fluorescent probe movement in a small light cavity with a defined volume generated by confocal illumination. We thus developed a highly sensitive determination system of H2O2 by FCS, where horseradish peroxidase (HRP) catalyzes the formation of a covalent bond between fluorescent molecules and proteins in the presence of H2O2. Our developed system gave a linear calibration curve for H2O2 in the range of 28 to 300 nM with the detection limit of 8 nM. In addition, by coupling with glucose oxidase (GOD)-catalyzed reaction, the method allows to measure glucose in the range of 80 nM to 1.5 µM with detection limit of 24 nM. The method was applicable to the assay of glucose in blood plasma. The mean concentration of glucose in normal human blood plasma was determined to be 4.9 mM.Conclusions/SignificanceIn comparison with commercial available methods, the detection limit and the minimum value of determination for glucose are at least 2 orders of magnitude more sensitive in our system. Such a highly sensitive method leads the fact that only a very small amount of plasma (20 nL) is needed for the determination of glucose concentration in blood plasma.

show abstract

“…4 Although the third generation electrochemical biosensors were believed to be the ideal sensors, few reports revealed the direct electrochemistry of Chox. [5][6][7] Chox, a flavin adenosine dinucleotide containing enzyme, which can catalyze the oxidation of cholesterol according to the following equation: cholesterol + O 2 / cholest-4-en-3-one + H 2 O 2 (1)…”

Section: Introductionmentioning

confidence: 99%

Selective determination of cholesterol based on cholesterol oxidase-alkaline phosphatase bienzyme electrode

Zhang

Liu

Zheng

2012

Analyst

View full text Add to dashboard Cite

A bienzyme electrode for the determination of cholesterol was prepared by the co-immobilization of cholesterol oxidase and alkaline phosphatase (ALP) on the carbon nanotubes modified electrode surface. The parameters influenced the performance of the bienzyme electrode such as the pH of the base solution; the concentration of DPP and the incubation time, were optimized. A linear calibration graph in the 0.05-2.0 mM concentration range with the sensitivity of 4.65 μA mM(-1) was obtained. In addition, this work provides a new interferent-depleted method and universal protocol for the design of multi-enzyme biosensors.

show abstract

Determination of free cholesterol based on a novel flow‐injection chemiluminescence method by immobilizing enzyme

Cited by 22 publications

References 45 publications

A multicommuted flow procedure for the determination of total and free cholesterol in eggs and human blood serum by chemiluminescence

A multicommuted flow procedure for the determination of total and free cholesterol in eggs and human blood serum by chemiluminescence

Highly Sensitive Determination of Hydrogen Peroxide and Glucose by Fluorescence Correlation Spectroscopy

Selective determination of cholesterol based on cholesterol oxidase-alkaline phosphatase bienzyme electrode

Contact Info

Product

Resources

About