PT  - JOURNAL ARTICLE
AU  - Steve Simmert
AU  - Mohammad Kazem Abdosamadi
AU  - Gero Hermsdorf
AU  - Erik Schäffer
TI  - LED-based interference-reflection microscopy combined with optical tweezers for quantitative three-dimensional single microtubule imaging
AID  - 10.1101/277632
DP  - 2018 Jan 01
TA  - bioRxiv
PG  - 277632
4099  - http://biorxiv.org/content/early/2018/03/07/277632.short
4100  - http://biorxiv.org/content/early/2018/03/07/277632.full
AB  - Optical tweezers combined with various microscopy techniques are a versatile tool for single-molecule force spectroscopy. However, some combinations may compromise measurements. Here, we combined optical tweezers with total-internal-reflection-fluorescence (TIRF) and interference-reflection microscopy (IRM). Using a light-emitting diode (LED) for IRM illumination, we show that single microtubules can be resolved with high contrast. Furthermore, we converted the IRM interference pattern of an upward bent microtubule to its three-dimensional (3D) profile calibrated against the optical tweezers and evanescent TIRF field. In general, LED-based IRM is a powerful method for high-resolution 3D microscopy.OCIS codes (180.3170) Interference microscopy; (120.4570) Optical design of instruments (350.4855); Optical tweezers or optical manipulation.