A Novel Potentiometric Sensor for Determination of Neurotoxin β-N-Oxalyl-L-α, β-Diaminopropionic Acid

Table 1

The composition and potentiometric performance characteristics of the all solid-state contact ODAP-selective membrane sensor.

Parameter	ODAP-sensitive membrane sensor
Membrane composition	%30.0 PVC
	%65.0 o-NPOE
	%2.5 ODAP-ionophore
	%1.5 di-cyclo-hexyl 18-crown-6-NaI
	%1.0 KTpClPB
Detection limit (mol/L)	1.2×10^−6
Linear range (mol/L)	1.0×10^−1--8.0×10^−6
Response time (s)	<6
Linear equation	𝑦=−34.6𝑥+2664.2
Correlation coefficient (𝑟^2)	0.9904
	Interfering	(𝑘^potOdap,interfering)
Selectivity coefficient (𝑘^potOdap,interfering)	K^+	1.88×10^−2
	Na^+	1.20×10^−2
	Ca^2+	3.96×10^−3

𝑘^pot_{Odap,interfering}: near interfering Na⁺, K⁺, and Ca²⁺ ions are reflected to exhibit selectivity to ODAP of sensor. The bigger the selectivity coefficient, 𝑘^pot_{Odap,interfering}, the smaller the sensitivity of the electrode towards ODAP measured.