The cryo 25° knife is designed for
sectioning frozen hydrated specimens.
The 25° angle results in the least possible compression and the best structure
preservation (H.M. Han et al., Journal of
Microscopy, Vol. 230, Pt. 2, pp. 167 – 171,
Please note: best results are achieved
at low humidiy, when the cryo-ultramicrotome is placed in a glovebox and the
sections attached by electrostatic force
(J. Pierson et al., Journal of Structural
Biology 169, pp. 219 – 225, 2010).
High resolution electron micrograph of vitreous section of keratin intermediate filaments in the midportion of stratum corneum of human epidermis. The fine structure of the keratin filaments is well resolved and their molecular organisation is seen in favourable cases (inset). Ashraf Al-Amoudi, Laboratoire d'Analyse Ultrastructurale, Lausanne.