TABLE 6.

Examples of impedimetric electrochemical biosensors for detection of whole bacterial cells^a

Bacterium(a)	Transducer	Chemistry	Bioreceptor	LOD	Reference
E. coli O157:H7	Gold	EDC/NHS	Antibody	2 CFU/ml	26
E. coli O157:H7	Nanoporous aluminum oxide membrane	Trimethoxysilane-HA-EDC/NHS	Antibody	10 CFU/ml	27
E. coli O157:H7	Nanoporous aluminum oxide membrane	Silane-PEG	Antibody	10 CFU/ml	92
E. coli K-12	Gold microelectrode, interdigitated	Physisorption	T4 bacteriophage	104–107 CFU/ml	87
E. coli K-12	Boron-doped UNCD microelectrode array	Physisorption	Antibody	NA	93
E. coli O157:H7	Gold microelectrode, interdigitated	Physisorption	Antibody	2.5 × 104 CFU/ml and 2.5 × 107 CFU/ml	94
E. coli	Gold	SAM-EDC/NHS	Antibody	1.0 × 103 CFU/ml	95
E. coli	Gold electrode	SAM-biotin-NeutrAvidin	Biotinyl antibody	10 CFU/ml	96
E. coli	7% gold-tungsten plate wire	Polyethyleneamine-streptavidin	Biotinyl antibody	103–108 CFU/ml	97
E. coli	Gold disk	mSAM	Synthetic glycan	102–103 CFU/ml	98
E. coli	Polysilicon interdigitated electrodes	Glutaraldehyde	Antibody	3 × 102 CFU/ml	99
E. coli O157:H7	Gold	SAM-HA-EDC/NHS	Antibody	7 CFU/ml	100
E. coli	Gold	SAM-PDICT cross-linker	Bacteriophage	8 × 102 CFU/ml	101
E. coli	Graphene paper	Biotin-streptavidin	Antibody	1.5 × 102 CFU/ml	102
E. coli	Screen-printed carbon microarrays	EDC/NHS	Bacteriophage	104 CFU/ml for 50-μl samples	103
Sulfate-reducing bacteria	Glassy carbon	Reduced graphene sheet with chitosan plus 1% glutaraldehyde	Antibody	1.8 × 101–1.8 × 107 CFU/ml	88
Sulfate-reducing bacteria	ITO	Chitosan-reduced grapheme sheet	Bioimprint of bacteria	1.0 × 104–1.0 × 108 CFU/ml	104
Sulfate-reducing bacteria	Foam Ni	Nanoparticle-SAM-EDC/NHS	Antibody	2.1 × 101–2.1 × 107 CFU/ml	105
Salmonella Typhimurium	Gold	SAM-glutaraldehyde	Antibody	NA	89
Salmonella Typhimurium	Electroplated gold on disposable printed circuit board	16-MHDA-EDC-NHS	Monoclonal antibody	10 CFU in 100 ml	106
Salmonella Typhimurium	Gold	Polytyramine-glutaraldehyde	Antibody	NA	107
Campylobacter jejuni	Glassy carbon	Physisorped onto O-carboxymethylchitosan surface-modified Fe3O4 nanoparticles	Monoclonal antibody	1.0 × 103–1.0 × 107 CFU/ml	90
Listeria innocua	Gold	SAM-EDC/NHS	Endolysin (bacteriophage-encoded peptidoglycan hydrolases)	1.1 × 104 and 105 CFU/ml	30
Staphylococcus aureus	Nanoporous alumina	Silane–1% GPMS	Antibody	102 CFU/ml	91
Porphyromonas gingivalis, E. coli	Microfluidic cell with hydrodynamic focusing	No immobilization/impedance reading during flow of cells	None	103 cells/ml	108

^aAbbreviations: EDC, ethyl(dimethylaminopropyl) carbodiimide; PEG, polyethylene glycol; UNCD, ultrananocrystalline diamond; NA, not available; PDICT, 1,4-dithiocyanate; ITO, indium tin oxide; mSAM, mixed self-assembled monolayer; NHS, N-hydroxysuccinimide; SAM, self-assembled monolayer; MHDA, mecaptohexadecanoic acid; GPMS, (3-glycidoxypropyl)trimethoxysilane.