Table 1.

Fluorescence lifetimes of free (τ₁) and protein-bound NADH (τ₂) and the ratio of their relative contribution (a₁:a₂) at the three different cell confluences (25,000, 100,000, and 1,000,000) for n = 6 experimental control days with the averages and SD for any given imaging session (16 data points) and the combined average and SD for all imaging sessions (96 data points)

Confluence	25,000			100,000			1,000,000
Confluence	τ₁ (ns) ± 0.05	τ₂ (ns) ± 0.1	Ratio (a₁:a₂)	τ₁ (ns) ± 0.05	τ₂ (ns) ± 0.1	Ratio (a₁:a₂)	τ₁ (ns) ± 0.05	τ₂ (ns) ± 0.1	Ratio (a₁:a₂)
n = 1	0.427	3.137	1.223	0.366	2.548	1.917	0.353	1.725	2.750
n = 2	0.388	2.920	1.015	0.393	2.588	1.743	0.355	1.735	2.900
n = 3	0.428	3.209	0.998	0.420	2.674	1.797	0.350	1.753	2.929
n = 4	0.455	3.190	1.167	0.420	2.586	2.051	0.346	1.720	2.875
n = 5	0.404	3.114	1.350	0.398	2.559	1.844	0.339	1.708	2.300
n = 6	0.433	3.067	1.298	0.388	2.434	1.972	0.358	1.700	2.458
Average	0.423	3.106	1.175	0.398	2.565	1.888	0.350	1.723	2.702
SD	0.023	0.105	0.145	0.021	0.078	0.115	0.007	0.019	0.262