Table 1.
Expression ratios of a weak and a bright spot on the same microarray, measured with three scanners at several PMT voltages
| ScanArray4000 I | ScanArray4000 II | GenePix4000B | |||||
| PMT (R/G) | Weak spot | Bright spot | Weak spot | Bright spot | PMT (R/G) | Weak spot | Bright spot |
| 62/62* | 2.28 | 0.74 | 1.88 | 0.60 | 800/700* | 1.63 | 0.61 |
| 56/62* | 2.43 | 0.76 | 1.79 | 0.58 | 700/700* | 1.68 | 0.55 |
| 50/62 | 2.15 | 0.74 | 1.49 | 0.61 | 500/700 | 1.58 | 0.47 |
| 45/62 | 1.26 | 0.95 | 0.43 | 0.71 | 400/700 | 4.98 | 0.47 |
| 40/62 | 0.55 | 1.41 | 0.16 | 0.76 | 300/700 | 14.14 | 0.98 |
| 62/56* | 2.25 | 0.76 | 1.93 | 0.62 | 800/500* | 1.71 | 0.61 |
| 62/50 | 2.36 | 0.71 | 2.12 | 0.58 | 800/400* | 1.79 | 0.64 |
| 62/45 | 3.37 | 0.62 | 3.75 | 0.50 | 800/300 | 1.75 | 0.62 |
| 62/40 | 92.9 | 0.48 | - | 0.41 | 800/200 | 0.10 | 0.46 |
Data subjected to total intensity normalization are shown. The PMT voltages (PMT) used during scanning are shown for the red (R) and green (G) channel separately as % of maximum voltage (ScanArray4000 I and II) or voltage (GenePix4000B). The PMT voltages leading to intensities within the usable range of the scanners and, hence, reproducible ratios for all spots in the array are indicated (*).