permanent and disposable Microtome blades
Disposable blades are easier to work with and produce better sections. A permanent Microtome blade has a longer lifespan but must be sharpened at regular intervals, usually every 6 months. Disposable blades are divided into two general categories, high profile and low profile.
Low profile blades are generally used for sectioning paraffin blocks. These blades are in smaller size than high profile blades and usually include a cover on the edge of the blades. The dimensions of this type of blade are usually 76mm * 8mm * 0.25mm . High profile disposable blades are heavier and can be used with or without a cover. The dimensions of these blades are usually 76mm * 14mm * 0.3mm.
If the blade edge is uncoated, the sectioning performance is limited in some parts and there will be resistance to sectioning and tissue pressure. Uncoated edges, work better for large disposable blades. blades with edges coated by materials like Teflon, polymer, ceramic or titanium nitride reduce friction between tissue and the blade and perform better sections, especially TiN coated edges increase edge life and for Hard tissue sections are suitable.
Permanent blades are available in 5 standard sizes. Usually made of stainless steel coated with chromium nitrate .
Diamond blades are suitable for sectioning hard tissues such as bone and they are not recommended for sectioning conventional paraffin blocks.