A question that keeps appearing in microscopy forums is: “Can I use an OpenFlexure microscope to image HeLa cells inside a mammalian CO₂ incubator?” It is a sensible question. Open-source hardware is attractive when budgets are tight, live-cell imaging is core to the project, and the existing shared research microscope is always booked.
This guide answers the question for UK labs. It explains what you actually need to image HeLa cells live, what OpenFlexure can deliver, and where commercial systems such as the EVOS M3000, M5000 and M7000 become the faster, more reliable option.
What Live HeLa Cell Imaging Actually Requires
HeLa cells are a hardy, fast-growing line, but they still need the same environment under the microscope as any mammalian culture:
- 37 °C temperature — maintained with a heated stage or incubator enclosure.
- 5% CO₂ — keeps bicarbonate-buffered media at the right pH.
- Humidity control — prevents evaporation during long time-lapses.
- Inverted optics — cells are imaged through the bottom of a dish or flask.
- Gentle illumination — LED sources reduce phototoxicity compared to mercury lamps.
- Sensitive camera — CMOS sensors that work at short exposures keep cells alive longer.
The hardware challenge is not the optics alone; it is keeping the cells alive for minutes, hours or days while you image them.
OpenFlexure as a DIY Live-Cell Microscope
OpenFlexure is a 3D-printed, open-source microscope built around a flexure translation stage. It was designed for low-cost microscopy in resource-limited settings, but the community has adapted it for fluorescence and live-cell work.
Advantages for DIY live-cell imaging
- Low cost — the base microscope can be printed and assembled for a fraction of a commercial system.
- Open design — you can modify the optics, camera and enclosure for incubator use.
- Web-based control — Raspberry Pi server lets you control the microscope from outside the incubator.
- Good for education and proof-of-concept — teaches optics and imaging from first principles.
Practical challenges for HeLa incubator imaging
- Humidity protection — electronics, 3D-printed plastics and cameras must survive a warm, humid incubator.
- Thermal drift — plastic stages expand more than metal ones, causing focus drift during time-lapse.
- No integrated CO₂ control — you need a custom gas line and chamber or rely on the incubator atmosphere.
- Fluorescence adds cost — filter cubes, excitation LEDs and a decent camera raise the price significantly.
- Support is community-based — debugging is slower than calling a vendor engineer.
Bottom line: OpenFlexure can image HeLa cells in a CO₂ incubator, but it is a build-and-validate project, not a turnkey solution. A 2026 preprint documents exactly this adaptation for affordable live-cell imaging.
When a Commercial Benchtop System Makes More Sense
If the goal is reliable, multi-user, publication-quality data, a commercial inverted system is usually the better investment. The EVOS line is the most direct comparison because it is also all-in-one and designed for cell-culture labs.
| Requirement |
DIY / OpenFlexure |
EVOS M7000 |
| Temperature / CO₂ / humidity |
Custom enclosure or incubator atmosphere only |
On-stage incubator (OSI-2) with active control |
| Focus stability over hours |
Depends on build quality; drift likely |
Motorised focus with Z-stack repeatability |
| Multi-well time-lapse |
Requires custom scripting and stage |
Built-in plate scanning and scheduled acquisition |
| Fluorescence filters / camera |
User-selected; no vendor guarantee of sensitivity |
Integrated LEDs, filter cubes and high-QE camera |
| Vendor support / warranty |
Community forums |
Thermo Fisher service and parts |
For labs that only need occasional phase-contrast checks, EVOS M3000 or M5000 with a simple on-stage incubator is the middle ground: you keep the all-in-one convenience and avoid the build time, without paying for full automation you do not need.
EVOS M3000, M5000 and M7000 for Live HeLa Imaging
Thermo Fisher’s EVOS systems are common in UK cell-culture labs because they sit on the bench, do not need a darkroom, and handle live cells directly.
EVOS M3000
Entry-level benchtop fluorescence and transmitted-light imaging. Good for routine morphology checks, GFP/RFP snapshots, and teaching labs that want an inverted system without a research-microscope price tag.
EVOS M3000 Review
EVOS M5000
Four-colour fluorescence with automated XY stage and larger monitor. Add the EVOS Onstage Incubator (OSI-2) for HeLa time-lapse in dishes or multiwell plates.
EVOS M5000 Review
EVOS M7000
Automated inverted system with on-stage incubator, Z-stacks, time-lapse and multi-well scanning. The default choice when live-cell imaging is central to the project and you need reproducible, multi-user data.
EVOS M7000 Review
Frequently Asked Questions
Can I use a DIY microscope to image HeLa cells in a CO₂ incubator?
Yes. Projects like OpenFlexure have been adapted for live-cell imaging inside mammalian CO₂ incubators. You need stable temperature, humidity and 5% CO₂, an inverted or stage-top optical path, a camera capable of low-light imaging, and protection of electronics from humidity. It is a build-and-tune project rather than a plug-and-play solution.
What makes live-cell imaging harder than fixed-cell imaging?
Live cells need stable temperature (37 °C), humidity and CO₂ to keep pH stable in bicarbonate-based media. They are also sensitive to light dose, so you need gentle LED illumination and a sensitive camera to avoid phototoxicity during time-lapse acquisition.
Do I need fluorescence for HeLa live-cell imaging?
Not necessarily. Phase contrast or label-free imaging works for morphology, growth and migration. Fluorescence is needed if you are tracking a GFP reporter, a stained organelle, or doing FRET/trafficking assays.
How does OpenFlexure compare to an EVOS M7000 for live-cell work?
OpenFlexure is low-cost, open-source and highly customisable, but you build and validate it yourself. EVOS M7000 is a commercial inverted system with integrated CO₂ on-stage incubator, automated multi-well time-lapse, Z-stacks and vendor support. OpenFlexure suits budget-limited or educational projects; EVOS suits labs that need reliable, repeatable, multi-user experiments.
What is the cheapest way to start live-cell imaging in a UK lab?
For a one-off project, adapting a USB camera onto an existing inverted tissue-culture microscope with a stage-top incubator is often cheapest. For a dedicated benchtop system, EVOS M3000 or M5000 with an on-stage incubator add-on removes the need for a separate research microscope. For a true DIY route, OpenFlexure with a Raspberry Pi HQ camera and custom incubator enclosure is the lowest hardware cost, but requires significant build time.
What control software do DIY live-cell microscopes use?
OpenFlexure uses its own Python-based server and web interface. µManager (Micro-Manager) is a popular open-source acquisition platform that works with many cameras and stages. These can be scripted for time-lapse, but lack the integrated analysis and multi-well automation of commercial platforms.