High-throughput analysis of the morphology and mechanics of tip growing cells using a microrobotic platform

Abstract

We present a microrobotic platform that combines MEMS-based capacitive force sensing technology, a dual-stage positioning system and a real-time control and acquisition architecture with computer vision automation to manipulate and mechanically characterize growing plant cells. The topography accuracy of the system, using a silicon wafer sample is measured to be 28 nm (1σ, 200Hz). With an SI-traceable stiffness reference we estimate the accuracy of the RT-CFM to be 3.49%. The target locations are selected from an interactive image of the workspace, and the sensing tip is positioned at each location using visual servoing techniques. Topography and stiffness maps were successfully obtained on growing pollen tubes. With the proposed system, cells can be mechanically stimulated at high speeds and with high precision while the intracellular components are visualized using confocal imaging. The system offers a versatile solution for dexterous and highthroughput characterization of biological specimen.

Feeling the force: how pollen tubes deal with obstacles

“…To simulate the natural environment of the pollen tube in vitro , we designed a system that forces the PTs to grow against a mechanical barrier or to squeeze through narrow gaps, while we simultaneously recorded the generated forces in real-time. The system combines a cellular force microscope (CFM) (Vogler et al ., 2013; Felekis et al ., 2011; Felekis et al ., 2014; Felekis et al ., 2015), equipped with a commercially available lateral force sensor, with a LOC for high-throughput pollen germination and guided parallelized PT growth, adapted from previous work by Shamsudhin and colleagues (2016) (Fig. 1A).…”

Feeling the force: how pollen tubes deal with obstacles

“…The system combines a lab‐on‐a‐chip (LOC) for high‐throughput pollen germination and guided parallelized PT growth, adapted from previous work by Shamsudhin et al . (), with a cellular force microscope (CFM) (Felekis et al ., , , ; Vogler et al ., ; Burri et al ., ), equipped with a commercially available lateral force sensor (FT‐S1000‐LAT; FemtoTools AG, Buchs, Switzerland) (Fig. a).…”

“…In order to simulate the natural environment of pollen tubes (PTs) in vitro, we designed a system that forces the PTs to grow against a mechanical barrier or to squeeze through narrow gaps, while we simultaneously recorded the generated forces in realtime. The system combines a lab-on-a-chip (LOC) for highthroughput pollen germination and guided parallelized PT growth, adapted from previous work by Shamsudhin et al (2016), with a cellular force microscope (CFM) (Felekis et al, 2011(Felekis et al, , 2014(Felekis et al, , 2015Vogler et al, 2013;Burri et al, 2016), equipped with a commercially available lateral force sensor (FT-S1000-LAT; FemtoTools AG, Buchs, Switzerland) ( Fig. 1a).…”

Measuring the Mechanical Properties of Plant Cell Walls

“…Automation is a key factor for high-throughput experiments, and to this end, the real-time CFM (RT-CFM) was developed [ 77 , 78 ]. By automating procedures, such as sample selection and mechanical loading, the experiment time is drastically reduced, which allows hundreds of measurements a day, whereas the CFM is limited to a few tens of measurements.…”

“…With the parallel kinematic design of the current system, cumulative guiding errors and backlash are avoided. At the same time, non-linearities, poor accuracy and off-axis motions are compensated for by a parallel metrology approach [ 77 , 78 ].…”