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Published on: February 1, 2018
Penicillin biosensor based on a capacitive field-effect structure functionalized with a dendrimer/carbon nanotube
José R Siqueira1, Maryam H Abouzar, Arshak Poghossian
1Instituto de Física de São Carlos, USP, CP 369, 13560-970 São Carlos, Brazil.
Biosensors & Bioelectronics
|August 5, 2009
Summary
This study developed a novel penicillin biosensor using functionalized silicon-based sensors with carbon nanotubes and dendrimers. The enhanced sensor shows high sensitivity and improved performance for detecting penicillin concentrations.
Area of Science:
- Materials Science
- Biosensors
- Nanotechnology
Background:
- Silicon-based biosensors offer advantages for miniaturized, robust biological recognition.
- Functionalization with nanomaterials like carbon nanotubes and dendrimers can enhance sensor capabilities.
Purpose of the Study:
- To functionalize field-effect (bio-)chemical sensors with layer-by-layer (LbL) films of single-walled carbon nanotubes (SWNTs) and polyamidoamine (PAMAM) dendrimers.
- To develop a penicillin biosensor based on an electrolyte-insulator-semiconductor (EIS) structure modified with carbon nanotubes (EIS-NT).
Main Methods:
- Fabrication of an EIS-NT structure and modification with penicillinase enzyme.
- Characterization using atomic force microscopy (AFM) and field-emission scanning electron microscopy (FESEM).
- Performance evaluation via capacitance-voltage (C/V) and constant-capacitance (ConCap) measurements.
Main Results:
- LbL films exhibited high porosity due to SWNT and dendrimer interpenetration.
- EIS-NT structures demonstrated high pH sensitivity (ca. 55 mV/pH).
- The penicillin biosensor showed a dynamic response to penicillin concentrations (5.0 µM to 25 mM) with a sensitivity of ca. 116 mV/decade.
Conclusions:
- The nanostructured PAMAM/SWNT LbL film significantly enhanced sensor sensitivity and overall performance.
- The developed EIS-NT-penicillinase biosensor is effective for penicillin detection.
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