Plasmonic micropillars for precision cell force measurement across a large field-of-view.

A plasmonic micropillar platform with self-organized gold nanospheres is reported for the precision cell traction force measurement across a large field-of-view (FOV). Gold nanospheres were implanted into the tips of polymer micropillars by annealing gold microdisks with nanosecond laser pulses. Each gold nanosphere is physically anchored in the center of a pillar tip and serves as a strong, point-source-like light scattering center for each micropillar. This allows a micropillar to be clearly observed and precisely tracked even under a low magnification objective lens for the concurrent and precision measurement across a large FOV. A spatial resolution of 30 nm for the pillar deflection measurement has been accomplished on this platform with a 20× objective lens.