Table 1.

Tabulated pH values and nitrite concentrations in artificial saliva samples spiked with different concentrations of nitrite using our PADs compared to standard methods.

Sample No.	Viscosity mPa-s	pH meter values (n=2)	pH from PADs (n=3)	Spiked nitrite concentrations (mg/dL)	UV-Vis (mg/dL nitrite) (n=4)	PADs (mg/dL nitrite) (n=6)
1.	1.54 ± 0.0035	4.965 ± 0.001	5.0-5.4	1.00	0.96 ± 0.02	0.72 ± 0.14
2.	1.54 ± 0.0035	8.015 ± 0.044	7.8	2.33	2.35 ± 0.02	1.94 ± 0.09
3.	1.87 ± 0.0032	7.197 ± 0.018	7.0-7.2	1.33	1.30 ± 0.02	1.14 ± 0.06
4.	1.87 ± 0.0032	6.560 ± 0.020	6.6	2.40	2.44 ± 0.07	1.95 ± 0.14
5.	2.18 ± 0.0035	5.705 ± 0.009	5.4-5.8	2.00	2.08 ± 0.04	1.75 ± 0.12
6.	2.18 ± 0.0035	8.129 ± 0.021	8.0	0.67	0.67 ± 0.00	0.69 ± 0.04
7.	2.73 ± 0.0075	7.216 ± 0.001	7.2-7.4	1.50	1.43 ± 0.01	1.57 ± 0.13
8.	2.73 ± 0.0075	8.041 ± 0.022	8.0	1.67	1.59 ± 0.01	1.84 ± 0.22
9.	4.17 ± 0.0083	6.909 ± 0.028	7.0	0.33	0.34 ± 0.03	0.30 ± 0.09
10.	4.17 ± 0.0083	8.467 ± 0.008	8.0-8.5	0.50	0.51 ± 0.02	0.57 ± 0.09
11.	5.10 ± 0.0894	6.043 ± 0.007	5.8	1.00	1.02 ± 0.01	1.13 ± 0.10
12.	5.10 ± 0.0894	7.897 ± 0.026	7.6-7.8	1.90	1.91 ± 0.03	1.92 ± 0.18
13.	1.54 ± 0.0035	7.164 ± 0.054	7.2	1.10	1.02 ± 0.02	0.95 ± 0.20
14.	1.87 ± 0.0032	7.132 ± 0.028	7.2	1.70	1.54 ± 0.02	1.62 ± 0.16
15.	2.18 ± 0.0035	7.155 ± 0.014	7.2	0.80	0.77 ± 0.01	0.77 ± 0.25
16.	2.18 ± 0.0035	7.155 ± 0.014	7.2	1.60	1.59 ± 0.03	1.64 ± 0.15
17.	2.73 ± 0.0075	7.082 ± 0.012	7.2	0	0	0
18.	2.73 ± 0.0075	7.082 ± 0.012	7.2	1.20	1.15 ± 0.04	1.24 ± 0.11
19.	4.17 ± 0.0083	7.151 ± 0.010	7.2	2.20	2.11 ± 0.08	2.25 ± 0.20
20.	5.10 ± 0.0894	7.082 ± 0.023	7.2	0.95	0.92 ± 0.02	0.92 ± 0.24