Surface assembly of nano-metal organic framework on amine functionalized indium tin oxide substrate for impedimetric sensing of parathion

• Published in: Biosensors & bioelectronics 2015-03, Vol.65, p.226-231
• Main Authors: Deep, Akash, Bhardwaj, Sanjeev Kumar, Paul, A.K., Kim, Ki-Hyun, Kumar, Pawan
• Format: Article
• Language: English
• Subjects: Amination; Antibodies, Immobilized - chemistry; Assembly; Biosensing Techniques - methods; Cadmium - chemistry; Detection; Dielectric Spectroscopy - methods; Electrochemical impedance spectroscopy; Immunosensors; Impedance; Indium tin oxide; Insecticides - analysis; Limit of Detection; Metal organic framework; Metal-organic frameworks; Nanostructure; Nanostructures - chemistry; Organometallic Compounds - chemistry; Oryza - chemistry; Oryza sativa; Parathion; Parathion - analysis; Pesticides; Phthalic Acids - chemistry; Self-assembly; Sensing; Sensors; Tin Compounds - chemistry
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2014.10.045

The present paper reports the assembly and pesticide sensing application of a nanometal organic framework [Cd(atc)(H2O)2]n (‘atc’=2-aminoterephthalic acid). The assembly of the NMOF film has been achieved by sequential dipping of a 2-aminobenzylamine (2-ABA) modified indium tin oxide (ITO) slide in organic linker ‘atc’ and metal ion ‘Cd2+’ solutions. The different structural and morphological characteristics of the NMOF thin film have been characterized. The availability of pendent –COOH functional groups on the assembled NMOF film is exploited to synthesize a pesticide immunosensor by conjugating the NMOF film with anti-parathion antibody. This immunosensor has been explored for the electrochemical impedance spectroscopy (EIS) based analysis of parathion in the concentration range of 0.1–20ng/mL. The proposed detection is specific with respect to other organophosphate compounds, e.g. malathion, paraoxon, fenitrothion, monochrotophos and dichlorovos. The proposed sensor shows the detection limit of 0.1ng/mL and it is applicable for analysis of parathion in a rice sample. The sensor's performance is validated by comparting the obtained results with gas chromatographic data. •NMOF films for developing a conductometric sensing platform.•Bioconjugation of NMOF thin films with anti-parathion antibody.•Demonstration of impedimentric sensing with NMOF.•Highly sensitive and specific detection of parathion.