Two major approaches to cryopreservation are known, ., conventional freeze-thaw procedures and vitrification, which is defined as a glass-like solidification (Karlsson & Toner, 1996). While freeze-thaw procedures minimize the probability of intracellular ice formation, vitrification attempts to prevent ice formation throughout the entire sample during the cooling and warming process (Kuleshova et al., 2007). Recently, the potential of vitrification has been tested for tissue-engineered constructs. Since tissue-engineered products consist of multicellular layers and often include biomaterials with varying coefficients of expansion compared with cells, cryopreservation using conventional freezethaw procedures with slow cooling rates has achieved limited success. Accordingly, vitrification could be an attractive alternative technology
