Refine
Year of publication
- 2024 (3)
- 2023 (6)
- 2022 (8)
- 2021 (14)
- 2020 (10)
- 2019 (14)
- 2018 (21)
- 2017 (29)
- 2016 (12)
- 2015 (32)
- 2014 (34)
- 2013 (26)
- 2012 (29)
- 2011 (34)
- 2010 (18)
- 2009 (29)
- 2008 (11)
- 2007 (15)
- 2006 (18)
- 2005 (11)
- 2004 (30)
- 2003 (25)
- 2002 (21)
- 2001 (36)
- 2000 (24)
- 1999 (19)
- 1998 (7)
- 1997 (5)
- 1996 (6)
- 1995 (2)
- 1993 (2)
Document Type
- Article (491)
- Conference Proceeding (46)
- Part of a Book (10)
- Book (2)
- Other (2)
Language
- English (551) (remove)
Keywords
- Biosensor (7)
- LAPS (4)
- field-effect sensor (4)
- hydrogen peroxide (4)
- Field-effect sensor (3)
- Label-free detection (3)
- Light-addressable potentiometric sensor (3)
- biosensors (3)
- capacitive field-effect sensor (3)
- tobacco mosaic virus (TMV) (3)
- Bacillus atrophaeus (2)
- Calorimetric gas sensor (2)
- Capacitive field-effect sensor (2)
- Hydrogen peroxide (2)
- Raman spectroscopy (2)
- Tobacco mosaic virus (TMV) (2)
- acetoin (2)
- capacitive field-effect sensors (2)
- gold nanoparticles (2)
- light-addressable potentiometric sensor (2)
Institute
Layer-by-Layer Assembly of Carbon Nanotubes Incorporated in Light-Addressable Potentiometric Sensors
(2009)
The ideal combination among biomolecules and nanomaterials is the key for reaching biosensing units with high sensitivity. The challenge, however, is to find out a stable and sensitive film architecture that can be incorporated on the sensor’s surface. In this paper, we report on the benefits of incorporating a layer-by-layer (LbL) nanofilm of polyamidoamine (PAMAM) dendrimer and carbon nanotubes (CNTs) on capacitive electrolyte-insulator-semiconductor (EIS) field-effect sensors for detecting urea. Three sensor arrangements were studied in order to investigate the adequate film architecture, involving the LbL film with the enzyme urease: (i) urease immobilized directly onto a bare EIS [EIS-urease] sensor; (ii) urease atop the LbL film over the EIS [EIS-(PAMAM/CNT)-urease] sensor; and (iii) urease sandwiched between the LbL film and another CNT layer [EIS-(PAMAM/CNT)-urease-CNT]. The surface morphology of all three urea-based EIS biosensors was investigated by atomic force microscopy (AFM), while the biosensing abilities were studied by means of capacitance–voltage (C/V) and dynamic constant-capacitance (ConCap) measureaments at urea concentrations ranging from 0.1 mM to 100 mM. The EIS-urease and EIS-(PAMAM/CNT)-urease sensors showed similar sensitivity (∼18 mV/decade) and a nonregular signal behavior as the urea concentration increased. On the other hand, the EIS-(PAMAM/CNT)-urease-CNT sensor exhibited a superior output signal performance and higher sensitivity of about 33 mV/decade. The presence of the additional CNT layer was decisive to achieve a urea based EIS sensor with enhanced properties. Such sensitive architecture demonstrates that the incorporation of an adequate hybrid enzyme-nanofilm as sensing unit opens new prospects for biosensing applications using the field-effect sensor platform.