With the development of tissue engineering and regeneration medicine, decellularized extracellular matrix (dECMs) has raised a lot of attention as they can provide a natural biochemical environment, availability, and lack of immunogenicity in host tissues. In addition, biologically active molecules, such as growth factors and cytokines can be maintained in the decellularized matrix. Therefore, extracellular matrix (ECM)-based scaffolds are considered as the most similar scaffold to the original tissue. ECMs have been widely used in the field

Time–temperature indicators (TTIs) are cost‐efficient tools that may be used to predict food quality. In this paper, a diffusion TTI was used to predict fruit quality during storage. Both the color changing characters of TTI and the quality parameters, including weight loss, soluble solids content, vitamin C content, titratable acidity, and antioxidant capacity of three kinds of fruits (kiwifruit, strawberry, and mango), were investigated for storage temperatures (5, 10, 15, and 20 °C). The relationships between the color changing properties and fruit quality parameters have been built based on the activation energy (Ea). The results showed that the storage temperature and time had significant effects on the color changing of TTI and fruit quality. The RGB value of TTI decreased with time, and the higher the storage temperature, the faster the RGB value reduced. Also, the higher the storage temperature, the faster the fruit quality changed and the poorer they were. Furthermore, all of the differences of Ea between TTI color response and fruit quality change are less than 25 kJ/mol, which indicates that the TTI can be used to predict these fruit quality. Finally, prediction models were built and validated based on the RGB values of TTI. It provides the possibility for low‐cost quality monitoring and has more application potential in food quality predicting. Practical Application By monitoring the color change of diffuse time–temperature indicator (TTI) and the quality change of fruit, the feasibility of TTI for fruit quality monitoring was determined and the quality prediction model was established. The diffusion TTI and fruit quality prediction model can realize the monitoring and predicting of fruit quality based on the TTI, which provides a basis for the combination of TTI Quick Response Code and fruit quality monitoring, with a view to achieving fruit quality status by scanning the Quick Response Code of TTI with mobile phones in the future. This method may provide a new solution to monitor the fruit quality during storage and distribution based on visualization technology that can simplify the methods of detecting fruit quality and achieve fast quality detection. It provides the possibility for low‐cost quality monitoring and has more application potential in food quality predicting. Further studies on diffusion TTI are needed to develop its application in more field of food and make the diffusion TTI an intelligent mean for food quality monitoring and predicting.

The successful rewarming of cryopreserved organs has always been a big challenge for the cryopreservation technology aimed at improving the shortage of available organs for transplantation. The traditional water bath rewarming produces more obvious devitrification and thermal stress damages, resulting in negative effects on the organ structure and physiological function. Nanowarming technology via induction heating of iron oxide nanoparticles for rewarming large-volume frozen biosamples is a promising strategy to overcome related problems. In this study, Fe 3 O 4 nanoparticles modified with carboxylic acid are used for nanowarming to rewarm the whole frozen kidney. The key steps including loading and elution of the cryoprotectant and magnetic nanoparticles (mNPs), vitrification of large-volume samples, and nanowarming of the whole kidney are explored in detail to achieve whole kidneys with a more integrated structure. Compared with water bath thawing, the nanowarming method could reduce the maximum thermal stress of the whole kidney by 2 orders of magnitude and has enough rewarming rate to avoid the devitrification phenomenon, so as to obtain a lower cell apoptosis rate, a more integrated vascular network, and a lower residual amount of mNPs inside the kidneys after elution. The optimization of the nanowarming method for the whole kidney could provide effective guidance for the large organ cryopreservation in clinical transplantation.

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Cryopreservation is currently a key step in translational medicine that could provide new ideas for clinical applications in reproductive medicine, regenerative medicine, and cell therapy. With the advantages of a low concentration of cryoprotectant, fast cooling rate, and easy operation, droplet-based printing for vitrification has received wide attention in the field of cryopreservation. This review summarizes the droplet generation, vitrification, and warming method. Droplet generation techniques such as inkjet printing, microvalve printing, and acoustic printing have been applied in the field of cryopreservation. Droplet vitrification includes direct contact with liquid nitrogen vitrification and droplet solid surface vitrification. The limitations of droplet vitrification (liquid nitrogen contamination, droplet evaporation, gas film inhibition of heat transfer, frosting) and solutions are discussed. Furthermore, a comparison of the external physical field warming method with the conventional water bath method revealed that better applications can be achieved in automated rapid warming of microdroplets. The combination of droplet vitrification technology and external physical field warming technology is expected to enable high-throughput and automated cryopreservation, which has a promising future in biomedicine and regenerative medicine.