Capillary wash of a Cover Pad-mounted sample in Omni-Stainer™ C12

At the heart of our systems is patented capillary gap exchange technology. A borosilicate Coverpad (for slides) or a Support Pad (for coverslips) with spacers creates a capillary chamber over the specimen. Hosting the samples in thin capillary exchange chambers enables microscopy staining automation since a liquid handler supplies reagents to the tops of the chambers. When a new buffer is added to the top, it is drawn into the chamber by the capillary force and laminar flow, instantly displacing the old buffer.

The tissue does not affect liquid flow as long as the tissue thickness is below the gap size, as in the example above (4 micron tissue within the 70 µm channel).

Both instruments can accommodate samples mounted on standard rectangular microscopy coverslips, 22x22 or 18x18 size, 0.17 mm thick.

Coverslip staining is less conventional than staining on slides but it is widely used in a number of applications, such as:
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1. Cell cultures - adherent cell lines are often grown on coverslips as they easily adhere to the glass and form micro-colonies
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2. TIRF - Total Internal Reflection Microscopy illuminates a thin surface layer of approx. ~200nm and therefore requires the sample to be adhered directly to the coverslip
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3. Some cyclic protocols that require on-microscope sample perfusion protocols, such as (classic) CODEX, CycIF, MERFISH, variations of STORM such as Exchange-PAINT - all require coverslip-mounted samples.

Most OCT fresh-frozen or FFPE tissue sample staining protocols are performed on slides. Those include PhenoCycler Fusion (PCF), GeoMx, SignalStar, RNAScope, Immunohistochemistry (IHC), Immunofluorescence (IF), In Situ Hybridization (ISH), Imaging Mass Cytometry (IMC), and many others.

Capillary wash of a Cover Pad-mounted sample
in Omni-Stainer™ C12

Yes. Both instruments can precisely control temperatures ranging from 0 to 100 °C, taking the guesswork and manual relocating of samples out of sample prep. The staining modules are made of heat-conductive aluminum. This enables a variety of protocols, such as FFPE Antigen Retrieval, smRNA-FISH, or CycIF to be performed directly onboard either system.

Capillary wash of a Cover Pad-mounted sample
in Omni-Stainer™ C12

There are many staining automation solutions on the market, with big names from prominent vendors. However, most of those systems are bulky, expensive, not particularly reagent-efficient, and are oriented toward clinical pathology labs. Since they are not designed to be used in a research setting with advanced spatial biology tools, such systems can be difficult to program and adapt to custom protocols. In contrast, Omni-Stainer™ and Spatial Station™ are compact, affordable, extremely flexible and easy to use. In addition, our systems have the unique capability to stain coverslip-mounted samples and precisely control temperature.

The flow chambers and modules are made of chemically inert materials, making them compatible with most aqueous buffers including those containing high-viscosity agents (e.g. dextran sulfate, glycerol), high salt buffers (up to 0.65M salt), detergents, DMF/DMSO, and semi-polar organic solvents (methanol, ethanol, isopropanol, acetone).

Non-polar solvents, such as petrol distillates or xylenes, are not compatible.