# Table 2 Nikolskii selectivity coefficients Kij for the three cation ISFETs with respect to three cations.

Na+K+$${\mathrm{NH}}_{4}^{+}$$
Na+ ISFET19.13 × 10−41.99 × 10−4
K+ ISFET6.45 × 10−213.16 × 10−1
$${\rm{NH}}_{4}^{+}$$ ISFET2.13 × 10−32.14 × 10−21