Table 2.

OP biosensors based on nonconducting polymer immobilized AChE.

Mode of detection	Transducer	Enzyme immobilization method	Minimum detection limit	Linearity	Substrate/enzyme inhibitor	Time of incubation (min)	Storage stability (days)	Reference
Amperometric	MWCNTs/PAN/Pt electrode	Affinity Bonding	5.0 × 10−9  μM	3.6 × 10−8–3.6 × 10−5  μM	Paraoxon	20	120	[26]
Amperometric	PAN/AuNPs/Pt electrode	Covalent Bonding	0.026 × 10−5  μM	3.6 × 10−7–3.6 × 10−4  μM	Paraoxon	20	30	[27]
Amperometric	MSF/PVA/GCE	Entrapment	0.2 × 10−3  μM	0.2 × 10−3–44.8 × 10−3  μM	Monocrotophos	10	30	[35]
Amperometric	PVA/SbQ/SPE	Entrapment	1.91 × 10−2  μM 1.24 × 10−3  μM	NR	Paraoxon and chlorpyrifos-ethyl oxon	10	Nr	[36]
Amperometric	PVA/SbQ/Pt Electrode	Entrapment	7.2 × 10−5, 0.18, and 0.049 μM	NR	Paraoxon, maneb, and thifensulfuron methyl	30	30	[30]
Amperometric	PAMAM-Au/CNTs/GCE	Electrostatic interaction	4.0 × 10−3  μM	4.8 × 10−3–9.0 × 10−2  μM	Carbofuran	9	21	[37]
Amperometric	MSF/PVA/GCE	Entrapment	0.05 ppb (0.2 nM)	0.05–10 ppb	Monocrotophos	10	30	[38]
Amperometric	Nylon Net	Covalent bonding	1.3–3.9 ppb	NR	Paraoxon	30	15–20	[39]
Amperometric	PBA/SbQ/Pt Electrode	Crosslinking	25 ppb–1.5 ppm	NR	Chlorpyrifos	15	NR	[40]

Note: NR: not reported.