Magnetic Tweezers
Almost all mechanical parts have been designed and fabricated by Nicolas Beyer @ IPCMS. The magnets: 2 cubes (5 mm) separated by 1 mm. N. Beyer .
Allan deviation (i.e. noise at a given bandwidth) along z (perpendicular to the glass surface) for a 1 micron bead (melted). 126 nm per pixel. 405 Hz. No drift correction.
Software
A custom made software (Labview + CUDA, X64) allows to track tens of molecules at hundreds of Hz and detect sub-nn displacements in real-time. The CUDA C/C++ code we used is based on the code written by Shawn Tabrizi (GitHub) when working in Saleh's Lab at UCSB (based on Vincent Croquette's work). One of our Internship students (Zhenxiang Luo, now at IMEC) helped ST to run it on X64 platforms and we did additional tweaks (e.g. Flat-Field correction). In the next few months, we will fully automize the MT device (injection of beads, recognition of (good) DNA beads, injection of relevant proteins).
Our current GPU is a MSI GeForce GTX 1060 Gaming X 3G allowing to track +50 beads (ROI: 64^2 pixels) at 400 Hz on 800 x 800 pixels images. The analysis is performed in real-time (all directions). As we use a buffered acquisition (using a Silicon Software frame grabber), there is no loss of frames.
Our Software (including a Silicon Software microEnable IV software for high-speed buffered acquisitions (CameraLink, Labview x64)) is available upon request (wilfried.grangeipcms.unistra.fr).
List of parts
| Description | Supplier | Product# |
|---|---|---|
| 95 mm Construction Rail | THORLABS | XT95-750 |
| Custom plate for Construction Rail | ||
| Rail Plate for 95 mm Rails | THORLABS | XT95P12/M |
| Rail Carrier | NEWPORT | CXL95-80 |
| Superluminescent Diode | SUPERLUM | SLD-mCS-261-MP2-SM |
| Fiber Out-coupler | THORLABS | PAF-X-2-B |
| XY Stage for Fiber | THORLABS | ST1XY-A/M |
| Post for Stage | THORLABS | RS75/M |
| Spacer for Post | THORLABS | RS2M |
| Lens tube spacer | THORLABS | SM1T20 |
| FiberPort Adapter | THORLABS | CP08FP/M |
| Translation Stage | PHYSIK INSTRUMENTE | M-126.PD1 |
| Controller for M-126.PD1 | PHYSIK INSTRUMENTE | C-863.11 |
| Rotation Stage | NANOTEC | ST4118M1804-L |
| Controller for ST4118M1804-L | NANOTEC | SMCI33-1 |
| Encoder | NANOTEC | NOE2-05-K10 |
| Power Supply | NANOTEC | NTS-24V-2A |
| XY Stage for Magnets | THORLABS | ST1XY-A/M |
| Post for Stage | THORLABS | TR30/M |
| Magnets | SUPERMAGNETE | W-05-N50-G |
| Custom Adaptor Plate | ||
| Objective | OLYMPUS | UPLFL 100XOI |
| PIFOC | PHYSIK INSTRUMENTE | P-726.1CD |
| PIFOC Controller | PHYSIK INSTRUMENTE | E-625 |
| Broadband Dielec. Mirror | NEWPORT | 10D20BD.1 |
| Mirror Mount | THORLABS | POLARIS-K25S4/M |
| 45 Degrees Adaptor | THORLABS | POLARIS-MA45/M |
| Column | NEWPORT | M-PS-1 |
| Imaging Lens | THORLABS | AC508-200-A |
| Camera | BAUMER | HXC-13 |
| Camera Link Add. Cable | BAUMER | 11008811 |
| Acquisition card | SILICON SOFTWARE | microEnable IV AD4-CL |
| Custom Enclosure System | MiSUMi | |
| 2" Diameter Lens Tubes | THORLABS | SM2LXX |
| Lens Tube Couplers | THORLABS | SM2TXX |
| Misc. Hardware (forks etc) | THORLABS | xx |
| Honeycomb Optical Table Top | STANDA | 1HT08-10-20-001 |
| Vibration Isolation System | STANDA | 1VIS10-05-07-70 |
| Syringe Pump | HARVARD Apparatus | PHD ULTRA 70-3005 |