Tricine as a Novel Cryoprotectant with Osmotic Regulation, Ice Recrystallization Inhibition and Antioxidant Properties for Cryopreservation of Red Blood Cells

Exploring the Cryopreservation Mechanism and Direct Removal Strategy of TAPS in Red Blood Cell Cryopreservation

Cryopreservation of red blood cells (RBCs) plays an indispensable role in modern clinical transfusion therapy. Researchers are dedicated to finding cryoprotectants (CPAs) with high efficiency and low toxicity to prevent RBCs from cryopreservation injury. This study presents, for the first time, the feasibility and underlying mechanisms of a novel CPA called tris(hydroxymethyl)aminomethane-3-propanesulfonic acid (TAPS) in RBCs cryopreservation. The results demonstrated that the addition of TAPS achieved a post-thaw recovery of RBCs at 79.12 ± 0.67%, accompanied by excellent biocompatibility (above 97%). Subsequently, the mechanism for preventing RBCs from cryopreservation injury was elucidated. On one hand, TAPS exhibits a significant amount of bound water and effectively inhibits ice recrystallization, thereby reducing mechanical damage. On the other hand, TAPS demonstrates high capacity to scavenge reactive oxygen species and strong endogenous antioxidant enzyme activity, providing effective protection against oxidative damage. Above all, TAPS can be readily removed through direct washing, and the RBCs after washing showed no significant differences in various physiological parameters (SEM, RBC hemolysis, ESR, ATPase activity, and Hb content) compared to fresh RBCs. Finally, the presented mathematical modeling analysis indicates the good benefits of TAPS. In summary, TAPS holds potential for both research and practical in the field of cryobiology, offering innovative insights for the improvement of RBCs cryopreservation in transfusion medicine.

Inulin Can Improve Red Blood Cell Cryopreservation by Promoting Vitrification, Stabilizing Cell Membranes, and Inhibiting Ice Recrystallization

In transfusion medicine, the cryopreservation of red blood cells (RBCs) is of major importance. The organic solvent glycerol (Gly) is considered the current gold-standard cryoprotectant (CPA) for RBC cryopreservation, but the deglycerolization procedure is complex and time-consuming, resulting in severe hemolysis. Therefore, it remains a research hotspot to find biocompatible and effective novel CPAs. Herein, the natural and biocompatible inulin, a polysaccharide, was first employed as a CPA for RBC cryopreservation. The presence of inulin could improve the thawed RBC recovery from 11.83 ± 1.40 to 81.86 ± 0.37%. It was found that inulin could promote vitrification because of its relatively high viscosity and glass transition temperature (Tg'), thus reducing the damage during cryopreservation. Inulin possessed membrane stability, which also had beneficial effects on RBC recovery. Moreover, inulin could inhibit the mechanical damage induced by ice recrystallization during thawing. After cryopreservation, the RBC properties were maintained normally. Mathematical modeling analysis was adopted to compare the performance of inulin, Gly, and hydroxyethyl starch (HES) in cryopreservation, and inulin presented the best efficiency. This work provides a promising CPA for RBC cryopreservation and may be beneficial for transfusion therapy in the clinic.

Advances in Cryopreservatives: Exploring Safer Alternatives

Cryopreservation of cells, tissues, and organs is widely used in the biomedical and research world. There are different cryopreservatives that are used for this process; however, many of them, such as DMSO, are used despite the problems they present, mainly due to the toxicity it presents to certain types of samples. The aim of this Review is to highlight the different types of substances used in the cryopreservation process. It has been shown that some of these substances are well-known, as in the case of the families of alcohols, sugars, sulfoxides, etc. However, in recent years, other compounds have appeared, such as ionic liquids, deep eutectic solvents, or certain polymers, which open the door to new cryopreservation methods and are also less toxic to frozen samples.

A Supramolecular Injectable Methacryloyl Chitosan-Tricine-Based Hydrogel with 3D Printing Potential for Tissue Engineering Applications

Printable hydrogels have attracted significant attention as versatile, tunable, and spatiotemporally controlled biomaterials for tissue engineering (TE) applications. Several chitosan-based systems are reported presenting low or no solubility in aqueous solutions at physiological pH. Herein, a novel neutrally charged, biomimetic, injectable, and cytocompatible dual-crosslinked (DC) hydrogel system based on a double functionalized chitosan (CHT) with methacryloyl and tricine moieties (CHTMA-Tricine), completely processable at physiological pH, with promising three-dimensional (3D) printing potential is presented. Tricine, an amino acid typically used in biomedicine, is capable of establishing supramolecular interactions (H-bonds) and is never explored as a hydrogel component for TE. CHTMA-Tricine hydrogels demonstrate significantly greater toughness (ranging from 656.5 ± 82.2 to 1067.5 ± 121.5 kJ m-3 ) compared to CHTMA hydrogels (ranging from 382.4 ± 44.1 to 680.8 ± 104.5 kJ m-3 ), highlighting the contribution of the supramolecular interactions for the overall reinforced 3D structure provided by tricine moieties. Cytocompatibility studies reveal that MC3T3-E1 pre-osteoblasts cells remain viable for 6 days when encapsulated in CHTMA-Tricine constructs, with semi-quantitative analysis showing ≈80% cell viability. This system's interesting viscoelastic properties allow the fabrication of multiple structures, which couple with a straightforward approach, will open doors for the design of advanced chitosan-based biomaterials through 3D bioprinting for TE.

Dynamic Regulation of the Interfacial pH for Highly Reversible Aqueous Zinc Ion Batteries

An electrolyte additive, with convenient operation and remarkable functions, has been regarded as an effective strategy for prolonging the cycle life of aqueous zinc ion batteries. However, it is still difficult to dynamically regulate the unstable Zn interface during long-term cycling. Herein, tricine was introduced as an efficient regulator to achieve a pH-stable and byproduct-free interface. The functional zwitterion of tricine not only inhibits interfacial pH perturbation and parasitic reactions by the trapping effect of an anionic group (-COO-) but also simultaneously creates a uniform electric field by the electrostatic shielding effect of a cationic group (-NH2+). Such synergy accordingly eliminates dendrite formation and creates a chemical equilibrium in the electrolyte, endowing the Zn||Zn cell with long-term Zn plating/stripping for 2060 h at 5 mA cm-2 and 720 h at 10 mA cm-2. As a result, the Zn||VS2 full cell under a high cathodic loading mass (8.6 mg cm-2) exhibits exceptional capacity retention of 93% after 1000 cycles.

Biophysics in Membrane of Cells

The membrane of a cell, often compared to a dynamic city border, carries out an intricate dance of controlling entry and exit, guarding the valuable life processes occurring inside [...].

Cryopreservation of tissues and organs: present, bottlenecks, and future

Tissue and organ transplantation continues to be an effective measure for saving the lives of certain critically ill patients. The organ preservation methods that are commonly utilized in clinical practice are presently only capable of achieving short-term storage, which is insufficient for meeting the demand for organ transplantation. Ultra-low temperature storage techniques have garnered significant attention due to their capacity for achieving long-term, high-quality preservation of tissues and organs. However, the experience of cryopreserving cells cannot be readily extrapolated to the cryopreservation of complex tissues and organs, and the latter still confronts numerous challenges in its clinical application. This article summarizes the current research progress in the cryogenic preservation of tissues and organs, discusses the limitations of existing studies and the main obstacles facing the cryopreservation of complex tissues and organs, and finally introduces potential directions for future research efforts.