DIY microscope set to save thousands of pounds
Top image: the DIY inverted microscope built to study cell motility [Brunel].
UK-based researchers have built a £160 inverted microscope system, using cheap parts they bought online, to measure cell motility.
Tests on a range of cells reveal that the DIY microscope, put together by Brunel University PhD student, Adam Lynch, and colleagues, delivers results on par with instruments costing thousands of pounds.
As Lynch explains, a basic commercial set-up to study cell motility demands an inverted microscope, digital camera, software and a heated stage, which all in, costs several thousand pounds.
Add on motorised stages and auto-focusing software for automated image acquisition, and the cost of the set-up soars to several hundred thousand pounds.
With this in mind, the researchers designed a set-up, based on three inverted USB desktop microscopes, for the cheap time-lapse imaging of cells.
"The frame was constructed using oak, the stage from acrylic and the microscope support base from adjustable kitchen unit legs," explains Lynch. "All three microscopes were identical Veho VMS-004D models... [each using] a CMOS image sensor with 1.3 mega-pixel resolution."
By clamping the microscopes upside down, on the frame, Lynch managed to enhance instrument stability and magnification, observing live samples in liquid.
He then went onto test various lighting sources, settling for an LED strip desk lamp as its low heat emission and intensity reduced stress on cell samples.
"The microscopes' inbuilt LEDs were turned off," he adds. "[And] to further reduce the risk of phototoxicity an accurate timer plug was used to turn the light off between image capturing."
Microscope system: (a) schematic, (b) CAD model, (c) photograph of finished system. [PLOS One/Lynch et al]
Lynch and colleagues also built an incubation chamber that used a soil warming cable to keep samples at a constant physiological temperature.
Made from transparent acrylic, the chamber's edges were fitted with foam to improve insulation, with the chamber secured above the stage with metal clips.
To capture images, the researchers wrote a custom application based on open source software, also using an open source Java-based image processing program to analyse cell motility.
Under this set-up, they went onto track cells from freshwater snails, young mice, as well as human breast cancer epithelial cells.
According to Lynch, their results were comparable to those obtained using standard, much more expensive equipment.
"Although resolution was lower than that of a standard inverted microscope, we found this difference to be indistinguishable at the magnification chosen for [our] cell tracking experiments," he says.
“If money is no object you can do something better but money certainly is an object and really the only way we could get meaningful data without spending a disproportionate amount of time in the lab was this,” he adds.
Lynch estimates the current system costs around £160, but could be made cheaper still.
He and colleagues expect the technology to be used within schools as well as by developing nations.
Research is published in PLOS One
Comparison of cell images between DIY system and a conventional optical microscope:
(a) 310× image taken at 640×480 with a conventional inverted microscope
(b) 206.8× image taken at 640×480 with DIY system and enlarged post acquisition by 149% to match the size
(c) 620× image taken at 1280×960 with a conventional inverted microscope, arrows show intra-cellular detail
(d) 1280×960 image taken with DIY system at full magnification (413.6×) and enlarged post-aquisition by 149% to match the size