The present application relates to a kind of fecal
bacteria cryopreservation and thawing method and
cryoprotectant.The concentration of permeable protective agent in the fecal
bacteria cryoprotectant is 350-400mg / ml, the concentration of impermeable protective agent is 110-130mg / ml, and the concentration of two-dimensional Ti3C2Tx
nanosheet is 0.2-0.6mg / ml.The present application also provides a method for
cryopreservation and thawing of fecal
bacteria using the
cryoprotectant, comprising the following steps: (1) preparing fecal bacteria; (2) preparing
alginate hydrogel loaded with fecal bacteria; (3)
cryopreservation of fecal bacteria; (4) thawing.The cryoprotectant of the present application contains two-dimensional Ti3C2Tx x
nanosheet, so it has passive ice inhibition and photothermal active ice inhibition function.During the cryopreservation process, two-dimensional Ti3C2Tx x
nanosheet has a significant
inhibitory effect on the formation and growth of
ice crystals.During the thawing process, two-dimensional Ti3C2Tx x nanosheet fully exerts its own
photothermal effect, absorbs the energy of near-
infrared laser and converts it into heat, acts as a high-efficiency space heat source, improves the uniformity of internal rewarming of the sample, and reduces the freezing damage caused by recrystallization and
devitrification.