Table 1.

Properties of different bio-fluids and Phosphate buffered saline (PBS).

Parameter	Sweat	Saliva	Serum	Blood	PBS buffer
Conductivity (S/m)	0.2–1.1	0.4	1.18	0.5-0.6	1.5–2
Viscosity (cP)	0.8–1.0	1.68	1.5	3.2	1.05
pH range	3.5–8.0	4.0–8.0	7.0–7.4	7.35–7.45	7.4