Fig. 4

Polylactic Acid (PLA) and sapphire material sample preparation. Two pieces cut from a spool of PLA printing filament ∼4 cm in length were placed on a Pyrex baking dish under a sapphire wafer (a) and then heated with a hot plate until melted (b). After melting, PLA pieces were removed from the Pyrex dish and sapphire wafers, then cut into coupons for biopanning trials (c), or cut into smaller pieces used for binding quantification (d) with equally sized sapphire pieces (e)