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Sensitive Electrochemical Immunosensor for Detection of Nuclear Matrix Protein-22 based on NH2-SAPO-34 Supported Pd/Co Nanoparticles.

Wu D, Wang Y, Zhang Y, Ma H, Yan T, Du B, Wei Q - Sci Rep (2016)

Bottom Line: The reduced graphene oxide-NH (rGO-NH) with good conductivity and large surface area was used to immobilize primary antibody (Ab1).Good reproducibility and stability have showed satisfying results in the analysis of clinical urine samples.This novel and ultrasensitive immunosensor may have the potential application in the detection of different tumor markers.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P.R. China.

ABSTRACT
A novel sandwich-type electrochemical immunosensor using the new amino group functionalized silicoaluminophosphates molecular sieves (NH2-SAPO-34) supported Pd/Co nanoparticles (NH2-SAPO-34-Pd/Co NPs) as labels for the detection of bladder cancer biomarker nuclear matrix protein-22 (NMP-22) was developed in this work. The reduced graphene oxide-NH (rGO-NH) with good conductivity and large surface area was used to immobilize primary antibody (Ab1). Due to the excellent catalytic activity toward hydrogen peroxide, NH2-SAPO-34-Pd/Co NPs were used as labels and immobilized secondary antibody (Ab2) through adsorption capacity of Pd/Co NPs to protein. The immunosensor displayed a wide linear range (0.001-20 ng/mL) and low detection limit (0.33 pg/mL). Good reproducibility and stability have showed satisfying results in the analysis of clinical urine samples. This novel and ultrasensitive immunosensor may have the potential application in the detection of different tumor markers.

No MeSH data available.


Related in: MedlinePlus

The cyclic voltammetry for each immobilized step in a PBS of pH 7.0 buffer solution containing 5 mmol/L K3[Fe(CN)6] on the response of the immunosensor to 10 ng/mL NMP-22. The bare GCE (a), rGO-NH/GCE (b), GA/rGO-NH/GCE (c), Ab1/GA/rGO-NH/GCE (d), BSA/Ab1/GA/rGO-NH/GCE (e), NMP-22/BSA/Ab1/GA/rGO-NH/GCE (f) and NH2-SAPO-34-Pd/Co-Ab2/NMP-22/BSA/Ab1/GA/rGO-NH/GCE (g).
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f4: The cyclic voltammetry for each immobilized step in a PBS of pH 7.0 buffer solution containing 5 mmol/L K3[Fe(CN)6] on the response of the immunosensor to 10 ng/mL NMP-22. The bare GCE (a), rGO-NH/GCE (b), GA/rGO-NH/GCE (c), Ab1/GA/rGO-NH/GCE (d), BSA/Ab1/GA/rGO-NH/GCE (e), NMP-22/BSA/Ab1/GA/rGO-NH/GCE (f) and NH2-SAPO-34-Pd/Co-Ab2/NMP-22/BSA/Ab1/GA/rGO-NH/GCE (g).

Mentions: The stepwise modified process of electrode was characterized by cyclic voltammetry (CV). CV can also characterize the modification process of the immunosensor besides electrochemical impedance spectroscopy, and each immobilization step was shown in Fig. 4. It could be seen that a pair of well-defined redox peak was observed on GCE (curve a), and this quasi-reversible one-electron redox peak was attributed to the transformation between Fe(CN)64− and Fe(CN)63−. The redox peak current increased strongly after rGO-NH was dropped onto the electrode surface (curve b), which suggested the rGO-NH had good conductivity and strong ability of electron transfer. The redox peak current decreased significantly after GA was dropped onto the rGO-NH modified electrode (curve c), which could be attributed to the large impedence of GA. The redox peak current decreased gradually when Ab1 (curve d), BSA (curve e) and NMP-22 (curve f) as the non-conductive bioactive substances were modified layer by layer on the electrode. The results suggested that the non-conductive bioactive substances were immobilized onto the electrode successfully and blocked electron exchange between the redox probe and the electrode. The redox peak current decreased to the minimum (curve g) when NH2-SAPO-34-Pd/Co-Ab2 were immobilized, indicated the formation of hydrophobic immunocomplex layer could embarrass electron transfer. As a result, the immunosensor was modified successfully.


Sensitive Electrochemical Immunosensor for Detection of Nuclear Matrix Protein-22 based on NH2-SAPO-34 Supported Pd/Co Nanoparticles.

Wu D, Wang Y, Zhang Y, Ma H, Yan T, Du B, Wei Q - Sci Rep (2016)

The cyclic voltammetry for each immobilized step in a PBS of pH 7.0 buffer solution containing 5 mmol/L K3[Fe(CN)6] on the response of the immunosensor to 10 ng/mL NMP-22. The bare GCE (a), rGO-NH/GCE (b), GA/rGO-NH/GCE (c), Ab1/GA/rGO-NH/GCE (d), BSA/Ab1/GA/rGO-NH/GCE (e), NMP-22/BSA/Ab1/GA/rGO-NH/GCE (f) and NH2-SAPO-34-Pd/Co-Ab2/NMP-22/BSA/Ab1/GA/rGO-NH/GCE (g).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4834490&req=5

f4: The cyclic voltammetry for each immobilized step in a PBS of pH 7.0 buffer solution containing 5 mmol/L K3[Fe(CN)6] on the response of the immunosensor to 10 ng/mL NMP-22. The bare GCE (a), rGO-NH/GCE (b), GA/rGO-NH/GCE (c), Ab1/GA/rGO-NH/GCE (d), BSA/Ab1/GA/rGO-NH/GCE (e), NMP-22/BSA/Ab1/GA/rGO-NH/GCE (f) and NH2-SAPO-34-Pd/Co-Ab2/NMP-22/BSA/Ab1/GA/rGO-NH/GCE (g).
Mentions: The stepwise modified process of electrode was characterized by cyclic voltammetry (CV). CV can also characterize the modification process of the immunosensor besides electrochemical impedance spectroscopy, and each immobilization step was shown in Fig. 4. It could be seen that a pair of well-defined redox peak was observed on GCE (curve a), and this quasi-reversible one-electron redox peak was attributed to the transformation between Fe(CN)64− and Fe(CN)63−. The redox peak current increased strongly after rGO-NH was dropped onto the electrode surface (curve b), which suggested the rGO-NH had good conductivity and strong ability of electron transfer. The redox peak current decreased significantly after GA was dropped onto the rGO-NH modified electrode (curve c), which could be attributed to the large impedence of GA. The redox peak current decreased gradually when Ab1 (curve d), BSA (curve e) and NMP-22 (curve f) as the non-conductive bioactive substances were modified layer by layer on the electrode. The results suggested that the non-conductive bioactive substances were immobilized onto the electrode successfully and blocked electron exchange between the redox probe and the electrode. The redox peak current decreased to the minimum (curve g) when NH2-SAPO-34-Pd/Co-Ab2 were immobilized, indicated the formation of hydrophobic immunocomplex layer could embarrass electron transfer. As a result, the immunosensor was modified successfully.

Bottom Line: The reduced graphene oxide-NH (rGO-NH) with good conductivity and large surface area was used to immobilize primary antibody (Ab1).Good reproducibility and stability have showed satisfying results in the analysis of clinical urine samples.This novel and ultrasensitive immunosensor may have the potential application in the detection of different tumor markers.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P.R. China.

ABSTRACT
A novel sandwich-type electrochemical immunosensor using the new amino group functionalized silicoaluminophosphates molecular sieves (NH2-SAPO-34) supported Pd/Co nanoparticles (NH2-SAPO-34-Pd/Co NPs) as labels for the detection of bladder cancer biomarker nuclear matrix protein-22 (NMP-22) was developed in this work. The reduced graphene oxide-NH (rGO-NH) with good conductivity and large surface area was used to immobilize primary antibody (Ab1). Due to the excellent catalytic activity toward hydrogen peroxide, NH2-SAPO-34-Pd/Co NPs were used as labels and immobilized secondary antibody (Ab2) through adsorption capacity of Pd/Co NPs to protein. The immunosensor displayed a wide linear range (0.001-20 ng/mL) and low detection limit (0.33 pg/mL). Good reproducibility and stability have showed satisfying results in the analysis of clinical urine samples. This novel and ultrasensitive immunosensor may have the potential application in the detection of different tumor markers.

No MeSH data available.


Related in: MedlinePlus