A compelling vision in nanomedicine is the use of self directed nanoparticles that can accumulate in areas of disease to perform designed functions, such as molecular delivery or destruction, endosomal release of genes or siRNA, and selective cell or tumor destruction with nano to macroscale spatiotemporal control and precision. These functions are increasingly achieved by gold nanoparticles (GNPs, such as sphere, shell or rod) that can be activated with a laser "switch". A defining aspect of this "switch" is GNP absorption of laser light and the ensuing heat generation and temperature change that can be confined or propagated through multiple scales from the nanoparticle surface up through bulk biological cells and tissues. In this critical review, we discuss the fundamental mechanisms of laser GNP heat generation, the measurement and modelling of the ensuing thermal response, and a number of the evolving biological applications dependent on this new technology (181 references).

The ability to replace organs and tissues on demand could save or improve millions of lives each year globally and create public health benefits on par with curing cancer. Unmet needs for organ and tissue preservation place enormous logistical limitations on transplantation, regenerative medicine, drug discovery, and a variety of rapidly advancing areas spanning biomedicine. A growing coalition of researchers, clinicians, advocacy organizations, academic institutions, and other stakeholders has assembled to address the unmet need for preservation advances, outlining remaining challenges and identifying areas of underinvestment and untapped opportunities. Meanwhile, recent discoveries provide proofs of principle for breakthroughs in a family of research areas surrounding biopreservation. These developments indicate that a new paradigm, integrating multiple existing preservation approaches and new technologies that have flourished in the past 10 years, could transform preservation research. Capitalizing on these opportunities will require engagement across many research areas and stakeholder groups. A coordinated effort is needed to expedite preservation advances that can transform several areas of medicine and medical science.

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Vitrification, a kinetic process of liquid solidification into glass, poses many potential benefits for tissue cryopreservation including indefinite storage, banking, and facilitation of tissue matching for transplantation. To date, however, successful rewarming of tissues vitrified in VS55, a cryoprotectant solution, can only be achieved by convective warming of small volumes on the order of one mL. Successful rewarming requires both uniform and fast rates in order to reduce thermal mechanical stress and cracks, and to prevent rewarming phase crystallization. Here we present a scalable nanowarming technology for 1 to 80 mL samples using radiofrequency-excited mesoporous silica coated iron oxide nanoparticles in VS55. Advanced imaging including Sweep Imaging with Fourier Transform and micro computed tomography were used to verify loading and unloading of VS55 and nanoparticles and successful vitrification of human dermal fibroblast cells, porcine arteries, and porcine aortic heart valve leaflet tissue. Nanowarming was then used to demonstrate uniform and rapid rewarming at > 130 °C/min in both physical (1 to 80 mL) and biological systems (1 to 50 mL). Nanowarming yielded viability that matched control and/or exceeded gold standard convective warming in 1 to 50 mL systems, and improved viability compared to slow warmed (crystallized) samples. Finally, biomechanical testing displayed no significant biomechanical property changes in blood vessel length or elastic modulus after nanowarming compared to untreated fresh control porcine arteries. In aggregate, these results demonstrate new physical and biological evidence that nanowarming can improve the outcome of vitrified cryogenic storage of tissues in larger sample volumes.