Effect of sample drying on micropatterning efficiency and improved micropatterning of S2 cells by fibrinogen anchors. (A and B) Sample drying during or after the micropatterning process affects micropatterning efficiency. (A) Drying of the pattern during or after the micropatterning process negatively impacts the micropatterning efficiency. Left: PLL-PEG–coated glass was processed for LIMAP patterning of fibrinogen-GFP (50 µg/ml). Middle: After imaging the pattern, the sample was dried, then rehydrated and imaged again in the same conditions. Right: PLL-PEG–coated glass was processed for LIMAP patterning of fibrinogen-GFP as before, but the sample was allowed to dry after the adsorption process. Two different dynamic ranges for visualization were used for each sample (top versus bottom line) so that each lane could be represented with the same dynamic range. (B) Protein adsorption to the non-micropatterned region is also increased upon drying during/after the micropatterning process. Sample was treated as in A, but nonpatterned regions were imaged. (C) Fibrinogen–Con A enhances the micropatterning of S2 cells. Con A (doped with 10% rhodamine–Con A) or fibrinogen–Con A (doped with 10% fibrinogen–Alexa546) was micropatterned at 50 µg/ml onto PLL-PEG–coated glass using deep UV and a chromium mask. Coverslips were washed, and S2 cells were added for 1 h before addition of SiR-tubulin, to label cells, for 30 min. After washing, cells and micropatterns were imaged by spinning-disc confocal microscopy. Micropatterning efficiency of S2 cells is lower on Con A compared with fibrinogen–Con A. Dashed line, region exposed to deep UV. Scale bars, 10 µm (A and B), and 100 µm (C).