The global cold chain is functioning but often ineptly, with consequences for food and vaccine supply worldwide. As ever, science is seeking to provide solutions.
Rwanda and climate change loomed large last year but the visit to the East African state by former minister and COP26 President Alok Sharma won little attention, though it involved a commitment to combat emissions from cooling technologies that make a substantial contribution to global levels overall.
World population growth, pandemic concerns and temperature rises mean demand for such tech to facilitate food and medicine supply will only increase. Logistics require products can be frozen for transportation via the long-established infrastructure of the international cold chain.
It’s a system that is increasingly failing because the half-century-old network is both costly and shockingly inefficient: World Health Organisation estimates suggest 50% of all vaccines are being discarded as spoilt; likewise, Africa Centre of Excellence for Sustainable Cooling and Cold-chain (ACES) Co-director, University of Birmingham Professor Toby Peters stated this applied in equal proportion to the fruit and vegetables transported and stored in sub-Saharan Africa.
Our goal is to make the transportation of vaccines and other life-saving biological materials more efficient and cost-effective, while also reducing the carbon footprint of this critical supply chain
Dr Asel Sartbaeva, CEO, EnsiliTech
Small wonder that the IoT for cold chain monitoring market is tipped to reach nearly US$ 18 billion by 2031 (Future Market Insights report 2023). But work is underway, especially in the life sciences to seek alternatives to current methods of freezing and cooling.
Refrigeration expert B Medical Systems is focused on servicing cell and gene therapy products fuelled by advances in stem cell research. However, as Marnick Dewilde, Chief Sales Officer Medical Refrigeration and Blood Management Solutions at B Medical Systems, observed recently, therapeutic effectiveness depends upon storage at constant, extreme low temperature.
Cryopreservation, freezing products at -196°C with the aid of liquid nitrogen, has been the favoured option. But this has implications for supply and availability, says Dewilde, because “cryopreservation is a very complex and expensive procedure that can limit the availability of these advanced therapies to only a small number of patients who need them”.
Yet a question remained as to how low temperatures needed to be and whether certain products could cope at a higher level. While product integrity remains sacrosanct, a variation upwards in temperature would offer both financial and practical benefits for individual businesses and patients. Lately, evidence had revealed some substances could remain stable even at temperatures just above -90°C, temperatures within the scope of so-called Ultra-Low Freezers (ULTs). Dewilde cites the example of one study of the stability of peripheral blood stem cells (PSBCs), comparing storage in liquid nitrogen and in ULTs, that revealed little difference after five years [1]. Additionally, studies comparing responses to freezing at -85°C and -196°C for dental pulp cells [2] and pancreatic islets [3] “found no loss of differentiation ability and functionality of the cell samples after more than six months storage at either temperature”, reports Dewilde.
Meanwhile, a more radical departure from traditional freezing and cooling is being pioneered by the one-time University of Bath spinout, EnsiliTech. It recently secured £1.2 million to assist in the development of its refrigeration-free method for vaccine transportation.
The patented platform relies on ensilication – using silica to form a protective, inorganic cage around biological material, rendering it stable and intact despite variations in external humidity and temperature. When required, the cage is broken and the active ingredient can be accessed in an unadulterated form.
Co-founder and CEO of EnsiliTech, Dr Asel Sartbaeva [pictured], commented: “Our goal is to make the transportation of vaccines and other life-saving biological materials more efficient and cost-effective, while also reducing the carbon footprint of this critical supply chain.”
Like its food equivalent, the vaccine cold chain dates back 50 years, in this case to the WHO Extended Programme of Immunisation. While successful in richer countries with better infrastructure and technology, inoculation rates in the poorest nations remain alarmingly low.
“The vaccine cold chain is costly, wasteful and after 50 years,” concludes EnsiliTech, “has become an obsolete technology, requiring an overhaul on how biologicals are stored and transported.”
Ensilication maintains the integrity of vaccines and other biological materials at temperatures ranging from -20°C to +80°C, says the company. Given that most vaccines need to be stored at sub-zero temperatures, and some at ultra-low temperatures, its potential for ‘democratising access to therapeutics and biologicals’ is apparent. Lack of reliable refrigeration continues to be a key obstacle to ensuring equity in healthcare and food supply. Seeking refinements and alternatives to traditional freezing technology offers a plausible response to aspects of that challenge, and aids both environmental and industrial efficiency gains.
Current levels of interest from the likes of the Science Angel Syndicate, Innovate UK and the Fink Family Office in EnsiliTech are likely to prove indicative of a wider investment trend over the decade.
References:
1 onlinelibrary.wiley.com/doi/10.1111/j.1537-2995.2009.02482.x
2 sciencedirect.com/science/article/abs/pii/S001122400900073X?via%3Dihub
3 journals.sagepub.com/doi/10.1177/0963689721999617
