Ultrathin, semithin, cryo dry & cryo wet sectioning of both materials and biological samples.
EDEN Instruments in association with MICROSTAR/RMC presents its new range of diamond knives
Sharp and…Precise!
A diamond knife for ultramicrotomy is an extremely sharp and precise diamond blade mounted in a metal holder called “boat”. Diamond knives are used for slicing very thin specimen sections which are magnified with an electron or optical microscope.
A Micro Star edge radius is about 2 nm or 12 carbon atoms. This molecular sharpness is needed in order to cut sections as thin as 25 nm. The sections are examined in the electron microscope at very high magnifications showing details sometimes less than 10 nm, and requiring the diamond knife to be defect free even at that scale.
Quality certified
A certificate of quality is included with every knife indicating the parameters of the final test, such as resin type, speed, section thickness, etc. This is signed and dated by the microtomist performing the test. In the end, the only criterion that defines the quality of a Micro Star diamond knife is its performance in your laboratory.
In details
Micro Star makes seven types of diamond knives and six boat styles. For most ultramicrotomy applications the standard diamond knife (type SU) in the standard boat (style S) is totally satisfactory. For some applications, such as cryo or histology sectioning, you may want to choose a diamond knife and boat designed for that application. See our catalog for detailed specifications and dimensions, or call if you need help in choosing a knife for a particular purpose.
There are two angles important in selecting and using diamond knives, the included angle and the clearance angle. The included angle is measured between the two facets that form the knife edge. The standard included angle in Micro Star knives is 45° used for routine sectioning. Optional angles are 35° and 55°.
Knives types and shapes
TYPE SU | Standard Ultramicrotomy | 25nm – 200nm
For sectioning of biological or materials specimens that will be inspected at the highest magnifications. Recommended for cutting sections with a thickness range from 25 to 200 nm. Available in diamond edge lengths from 1 to 6 mm. Mounted in boat style S or any other requested style.
TYPE CW | Cryo Ultramicrotomy Wet | 50nm – 1µm | -200°C
For sectioning at cryogenic temperatures down to -200° C using liquids, like ethylene glycol, to float the sections. Recommended for cutting sections with a thickness range from 50 nm to 1 µm. Available in diamond edge lengths from 1 to 6 mm. Mounted in boat style W.
TYPE CD | Cryo Ultramicrotomy Dry | 50nm – 1µm | -200°C
For sectioning dry at cryogenic temperatures down to -200° C. Recommended for cutting sections with a thickness range from 50 nm to 1 µm. Available in diamond edge lengths from 1 to 6 mm. Mounted in boat style D.
TYPE TS | Thick-Thin sectioning | 50nm – 2µm
For sectioning thick or alternating thick and thin sections. Recommended for cutting sections with a thickness range from 50 nm to 2 µm. Available in diamond edge lengths from 1 to 6 mm. Mounted in boat style S or any other requested style.
TYPE MT | Materials Science | 50nm – 2µm
For industrial materials sectioning, not tested to the same ultra high standards as the types above, hence its lower price. Recommended for cutting sections with a thickness range from 50 nm to 2 µm. Available in diamond edge lengths from 2 to 7 mm. Mounted in boat style S or any other requested style.
TYPE LC | Light Microscopy Cryo | 0,1µm – 5µm
Sectioning for light microscopy or histology applications at cryogenic temperatures wet or dry. Recommended for cutting sections with a thickness range from 0.1 to 5 µm. Available in diamond edge lengths from 4 to 7 mm. Mounted in boat style W or D for wet or dry sectioning respectively.
S
Standard boat with oval cavity, black anodized. All knives are supplied in this boat unless otherwise requested.
W
For wet cryo sectioning. stainless steel with mate of non glare finish and cylindrical cavity. 6° inclined top.
D
For dry cryo sectioning. Stainless steel non glare finish.
H
Cylindrical cavity, 6° inclined top. Available in black or non glare blue anodizing.
M
Wide oval cavity boat. Black anodized.
K
Large boat with cylindrical cavity and 6° inclined top. Supplied with knives with edges from 7 to 10 mm long.
The following table shows the range of standard sizes and styles available :
| Types | Size (mm) | Angle | Sections thickness range | Applications |
| SU | 1 mm to 8 mm | 45° 35° 55° | 25 nm to 200 nm | Ultramicrotomie standard de routine. |
| CW | 1 mm to 8 mm | 45° 35° | 50 nm to 1 µm | Coupes de spécimens hydratés-congelés. Monté sur un support “bateau” type W. |
| CD | 1 mm to 8 mm | 45° 35° | 50 nm to 1 µm | Coupes sèches de spécimens congelés. Monté sur un support “bateau” type D. |
| TS | 1 mm to 8 mm | 45° 55° | 50 nm to 2 µm | Sections épaisses ou sections alternées fines/épaisses. |
| MT | 2 mm to 8 mm | 45° 55° | 50 nm to 2 µm | Coupes de matériaux industriels. |
| LC | 4 mm to 12 mm | 45° 55° | 0,1 µm to 2 µm | Spécimens congelés à étudier en microscopie optique. Monté sur un support “bateau” type D ou W. |
| LH | 4 mm to 12 mm | 45° 55° | 0,1 µm to 2 µm | Sections examinées en microscopie optique. |