An exploratory study on isochoric supercooling preservation of the pig liver

This study was motivated by the increasing interest in finding ways to preserve organs in a supercooled state for transplantation. Previous research with small volumes suggests that the isochoric (constant volume) thermodynamic state enhances the stability of supercooled solutions.The primary objective of this study was to investigate the feasibility of storing a large organ, such as the pig liver, in a metastable isochoric supercooled state for clinically relevant durations. To achieve this, we designed a new isochoric technology that employs a system consisting of two domains separated by an interior boundary that can transfer heat and pressure, but not mass. The liver is preserved in one of these domains in a solution with an intracellular composition, which is in osmotic equilibrium with the liver. Pressure is used to monitor the thermodynamic state of the isochoric chamber. In this feasibility study, two pig livers were preserved in the device in an isochoric supercooled state at -2°C. The experiments were terminated voluntarily, one after 24 h and the other after 48 h of supercooling preservation. Pressure measurements indicated that the livers did not freeze during the isochoric supercooling preservation. This is the first proof that organs as large as the pig liver can remain supercooled for extended periods of time in an isotonic solution in an isochoric system, despite an increased probability of ice nucleation with larger volumes. To serve as controls and to test the ability of pressure monitoring to detect freezing in the isochoric chamber, an experiment was designed in which two pig livers were frozen at -2°C for 24 h and the pressure monitored. Histological examination with H&E stains revealed that the supercooled liver maintained a normal appearance, even after 48 h of supercooling, while tissues in livers frozen to -2°C were severely disrupted by freezing after 24 h

An exploratory study on isochoric supercooling preservation of the pig liver

This study was motivated by the increasing interest in finding ways to preserve organs in a supercooled state for transplantation. Previous research with small volumes suggests that the isochoric (constant volume) thermodynamic state enhances the stability of supercooled solutions. The primary objective of this study was to investigate the feasibility of storing a large organ, such as the pig liver, in a metastable isochoric supercooled state for clinically relevant durations. To achieve this, we designed a new isochoric technology that employs a system consisting of two domains separated by an interior boundary that can transfer heat and pressure, but not mass. The liver is preserved in one of these domains in a solution with an intracellular composition, which is in osmotic equilibrium with the liver. Pressure is used to monitor the thermodynamic state of the isochoric chamber. In this feasibility study, two pig livers were preserved in the device in an isochoric supercooled state at -2°C. The experiments were terminated voluntarily, one after 24 h and the other after 48 h of supercooling preservation. Pressure measurements indicated that the livers did not freeze during the isochoric supercooling preservation. This is the first proof that organs as large as the pig liver can remain supercooled for extended periods of time in an isotonic solution in an isochoric system, despite an increased probability of ice nucleation with larger volumes. To serve as controls and to test the ability of pressure monitoring to detect freezing in the isochoric chamber, an experiment was designed in which two pig livers were frozen at -2°C for 24 h and the pressure monitored. Histological examination with H&E stains revealed that the supercooled liver maintained a normal appearance, even after 48 h of supercooling, while tissues in livers frozen to -2°C were severely disrupted by freezing after 24 h

Isochoric Supercooling Organ Preservation System.

This technical paper introduces a novel organ preservation system based on isochoric (constant volume) supercooling. The system is designed to enhance the stability of the metastable supercooling state, offering potential long-term preservation of large biological organs at subfreezing temperatures without the need for cryoprotectant additives. Detailed technical designs and usage protocols are provided for researchers interested in exploring this field. The paper also presents a control system based on the thermodynamics of isochoric freezing, utilizing pressure monitoring for process control. Sham experiments were performed using whole pig liver sourced from a local food supplier to evaluate the systems ability to sustain supercooling without ice nucleation for extended periods. The results demonstrated sustained supercooling without ice nucleation in pig liver tissue for 24 and 48 h. These findings suggest the potential of this technology for large-volume, cryoprotectant-free organ preservation with real-time control over the preservation process. The simplicity of the isochoric supercooling device and the design details provided in the paper are expected to serve as encouragement for other researchers in the field to pursue further research on isochoric supercooling. However, final evidence that these preserved organs can be successfully transplanted is still lacking

Isochoric Supercooling Organ Preservation System

This technical paper introduces a novel organ preservation system based on isochoric (constant volume) supercooling. The system is designed to enhance the stability of the metastable supercooling state, offering potential long-term preservation of large biological organs at subfreezing temperatures without the need for cryoprotectant additives. Detailed technical designs and usage protocols are provided for researchers interested in exploring this field. The paper also presents a control system based on the thermodynamics of isochoric freezing, utilizing pressure monitoring for process control. Sham experiments were performed using whole pig liver sourced from a local food supplier to evaluate the system’s ability to sustain supercooling without ice nucleation for extended periods. The results demonstrated sustained supercooling without ice nucleation in pig liver tissue for 24 and 48 h. These findings suggest the potential of this technology for large-volume, cryoprotectant-free organ preservation with real-time control over the preservation process. The simplicity of the isochoric supercooling device and the design details provided in the paper are expected to serve as encouragement for other researchers in the field to pursue further research on isochoric supercooling. However, final evidence that these preserved organs can be successfully transplanted is still lacking