A novel approach for the selective analysis of l-lysine in untreated human serum by a co-crosslinked l-lysine–α-oxidase/overoxidized polypyrrole bilayer based amperometric biosensor

Ciriello, Rosanna; Gennaro, Francesca; Frascaro, Silvio; Guerrieri, Antonio

doi:10.1016/j.bioelechem.2018.07.004

Cited by 19 publications

(23 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The modification of the Pt electrode by overoxidized polypyrrole, before choline oxidase (ChO) immobilization by co-crosslinking, could successfully solve this problem. This film is characterized by notable rejection properties towards interferents, as already demonstrated in the case of other enzymes and analytes [26][27][28].…”

Section: Introductionsupporting

confidence: 55%

“…Furthermore, the presence of the underlying overoxidized polypyrrole film guaranteed a notable rejection of interferent compounds, electroactive at the high overpotential required to detect H 2 O 2 , thus allowing the application of the sensor to assay Cholinesterase in real samples as complex as human serum [29]. Electrochemical, XPS, and ESEM characterizations of these biosensors were already described elsewhere [28][29][30][32][33][34][35]. Based on these important achievements, in the present work we wanted to employ such a biosensor to develop a novel PLD assay method.…”

Section: Scheme 1 Fabrication Steps Of the Biosensor (A) And Currentmentioning

confidence: 99%

See 1 more Smart Citation

Assay of Phospholipase D Activity by an Amperometric Choline Oxidase Biosensor

Ciriello

Guerrieri

2020

Sensors

Self Cite

View full text Add to dashboard Cite

A novel electrochemical method to assay phospholipase D (PLD) activity is proposed based on the employment of a choline biosensor realized by immobilizing choline oxidase through co-crosslinking on an overoxidized polypyrrole film previously deposited on a platinum electrode. To perform the assay, an aliquot of a PLD standard solution is typically added to borate buffer containing phosphatidylcholine at a certain concentration and the oxidation current of hydrogen peroxide is then measured at the rotating modified electrode by applying a detection potential of +0.7 V vs. SCE. Various experimental parameters influencing the assay were studied and optimized. The employment of 0.75% (v/v) Triton X-100, 0.2 mM calcium chloride, 5 mM phosphatidylcholine, and borate buffer at pH 8.0, ionic strength (I) 0.05 M allowed to achieve considerable current responses. In order to assure a controlled mass transport and, at the same time, high sensitivity, an electrode rotation rate of 200 rpm was selected. The proposed method showed a sensitivity of 24 (nA/s)⋅(IU/mL)−1, a wide linear range up to 0.33 IU/mL, fast response time and appreciable long-term stability. The limit of detection, evaluated from the linear calibration curve, was 0.005 IU/mL (S/N = 3). Finally, due to the presence of overoxidized polypyrrole film characterized by notable rejection properties towards electroactive compounds, a practical application to real sample analysis can be envisaged.

show abstract

Section: Introductionsupporting

confidence: 55%

Section: Scheme 1 Fabrication Steps Of the Biosensor (A) And Currentmentioning

confidence: 99%

Assay of Phospholipase D Activity by an Amperometric Choline Oxidase Biosensor

Ciriello

Guerrieri

2020

Sensors

Self Cite

View full text Add to dashboard Cite

show abstract

“…Until now, the main application of immobilised LO is instead for Lys assay. Indeed, several Lys biosensors have been described, and in the authors’ laboratory, a novel, highly selective LO (from Trichoderma viride )-based amperometric biosensor has been developed, which proved useful and effective for the selective Lys analysis in pharmaceutical and food samples, and in untreated human serum as well [ 12 , 13 , 14 , 15 ] (see those references for updated information about the Lys biosensors described thus far and for a critical comparison). Particularly, the selectivity problem of the Lys assay required a careful study and control of the kinetic behaviour of the sensing device and, interestingly, during those studies, unexpected anomalies in LO enzyme kinetics were observed.…”

Section: Introductionmentioning

confidence: 99%

Allosteric Enzyme-Based Biosensors—Kinetic Behaviours of Immobilised L-Lysine-α-Oxidase from Trichoderma viride: pH Influence and Allosteric Properties

et al. 2020

Self Cite

View full text Add to dashboard Cite

The present study describes the kinetics of L-lysine-α-oxidase (LO) from Trichoderma viride immobilised by co-crosslinking onto the surface of a Pt electrode. The resulting amperometric biosensor was able to analyse L-lysine, thus permitting a simple but thorough study of the kinetics of the immobilised enzyme. The kinetic study evidenced that LO behaves in an allosteric fashion and that cooperativity is strongly pH-dependent. Not less important, experimental evidence shows that cooperativity is also dependent on substrate concentration at high pH and behaves as predicted by the Monod-Wyman-Changeux model for allosteric enzymes. According to this model, the existence of two different conformational states of the enzyme was postulated, which differ in Lys species landing on LO to form the enzyme–substrate complex. Considerations about the influence of the peculiar LO kinetics on biosensor operations and extracorporeal reactor devices will be discussed as well. Not less important, the present study also shows the effectiveness of using immobilised enzymes and amperometric biosensors not only for substrate analysis, but also as a convenient tool for enzyme kinetic studies.

show abstract

“…However, because most amino acids are electrochemically less active, derivatization methods are also used in HPLC with electrochemical detection (HPLC-ECD) [17]. In the other methods, enzyme-immobilized or chemically modified electrodes for voltammetry have been developed to determine a specific amino acid [18][19][20]. Although these electroanalytical methods allow for the sensitive and selective determination of amino acids, they require complicated procedures such as derivatization with electroactive reagents and the preparation and maintenance of modified electrodes.…”

Section: Introductionmentioning

confidence: 99%

“…Amino acid analysis is an important technique in many pharmaceutical, medical, chemical, food research, and industrial areas [1][2][3]. Thus far, various analytical methods have been proposed to determine amino acids, including high-performance liquid chromatography, capillary electrophoresis, enzyme assay, and chemical sensors [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21]. Usually, because of the weak light-absorptive property of amino acids, pre-or post-column derivatization with an appropriate labeling reagent is performed for determining amino acids with sensitivity and selectivity in HPLC with UV detection (HPLC-UV) and fluorescence detection (HPLC-FL) systems [9,10].…”

Section: Introductionmentioning

confidence: 99%

Voltammetric Determination of Amino Acids Based on the Measurement of Reduction Prepeak of Quinone Caused by Surplus Acid after Neutralization

et al. 2018

View full text Add to dashboard Cite

In the voltammetric reduction of quinone, such as 3,5‐di‐tert‐butyl‐1,2‐benzoquinone (DBBQ), in the presence of HCl, a reduction prepeak of DBBQ caused by HCl can be observed on a voltammogram. Here, we have shown that the prepeak height of DBBQ is linearly decreased with increasing concentrations of amino acid in an electrolyte solution when this voltammetry is performed after neutralization between amino acids and excess HCl. This finding is based on a concept of acid‐base back titration of amino acids with excess HCl where surplus HCl gives a reduction prepeak of DBBQ. In this study, the reduction behaviors of DBBQ in the presence of amino acids and HCl have been provided to develop a novel electroanalytical method for the determining of amino acids. Electrochemical detection of 20 kinds of α‐amino acids, including less electroactive ones, has been achieved using a bare plastic formed carbon working electrode. Moreover, a flow injection analysis with electrochemical detection system using a glassy carbon working electrode is developed based on the present detection principle, and it has been applied to the determination of glutamine in an L‐glutamine granulated powder.

show abstract

A novel approach for the selective analysis of l-lysine in untreated human serum by a co-crosslinked l-lysine–α-oxidase/overoxidized polypyrrole bilayer based amperometric biosensor

Cited by 19 publications

References 30 publications

Assay of Phospholipase D Activity by an Amperometric Choline Oxidase Biosensor

Assay of Phospholipase D Activity by an Amperometric Choline Oxidase Biosensor

Allosteric Enzyme-Based Biosensors—Kinetic Behaviours of Immobilised L-Lysine-α-Oxidase from Trichoderma viride: pH Influence and Allosteric Properties

Voltammetric Determination of Amino Acids Based on the Measurement of Reduction Prepeak of Quinone Caused by Surplus Acid after Neutralization

Contact Info

Product

Resources

About