The process of complex coacervation keeps viruses in vaccine solutions stable by crowding them tightly together, reducing the need for refrigeration.
Graphic Credit: Caryn Heldt and Sarah Perry
Half of vaccines are wasted annually because they aren’t kept cold. Chemical engineers have discovered a way to stabilize viruses in vaccines with proteins instead of temperature.
Ever receive a vaccination that seemed to burn while it was injected? The vaccine solution likely contained a lot of salt or sugar — natural preservatives that help keep it stable, in addition to the cold temperature at which it was kept.
The viruses in vaccines, which train our cells to identify and vanquish viral invaders, must be kept cold to keep them from bursting apart. The typical shipping temperature for vaccines ranges from 2 to 8 degrees Celsius (35 to 47 degrees Fahrenheit).
Viruses are kept cold for the same reason we refrigerate food items. “You wouldn’t take a steak and leave it out on your counter for any length of time and then eat it,” said Caryn Heldt, director of the Health Research Institute at Michigan Technological University and professor of chemical engineering. “A steak has the same stability issues — it has proteins, fats, and other molecules that, in order to keep them stable, we need to keep them cold.”
Like proteins, viruses unfold when it’s hot or there’s space to move around. Heat provides energy for viruses to shake themselves apart, and not being crowded gives them the room to fall apart. Stable vaccines need cold or crowding.
But what if cold storage isn’t available? What if someone accidentally leaves the package on the counter? What if the power goes out?
Heldt, together with Sarah Perry, professor of chemical engineering at the University of Massachusetts Amherst, has developed a way to mimic the body’s environment in vaccines using a process called complex coacervation. Rather than relying on refrigeration, Perry and Heldt tap the other method to keep viruses stable — crowding.
To keep the viruses in vaccines stable, everyone along the supply chain, from manufacturing facility to shipping company to doctor’s office, must maintain the cold temperature. This cooperative effort is known as the cold chain. If a vaccine is kept above that temperature range for even an hour, it may become ruined and unusable.
The World Health Organization estimates that up to 50% of vaccines are wasted every year because the cold chain and ideal temperature for storage cannot be maintained.
The human body is a crowded place. Cells of varying shapes and sizes jockey for position. This includes viruses, which do their nefarious work by hostile takeover. Viruses invade our cells, commandeering them to replicate. Unchecked, virus copies explode out of the cells like darts through a balloon. Then all of those replicas go and do the same to other cells — and before you know it, you’re sick.
Heldt researches vaccine manufacturing techniques and the COVID-19 pandemic has served as a masterclass. But SARS-CoV-2 isn’t the only virus in the world — there is still need for other vaccines and storage methods that don’t rely on refrigeration.
“The conditions for a vaccine that make it good to be injected into someone’s body are almost the opposite of what makes a virus stable,” Heldt said. “There’s a really hard trade-off of keeping the virus stable to get good immune response, while having the right components in the vaccine that are safe to inject.”
Heldt and Perry use polypeptides — synthetic proteins — that have positive or negative charges. When these charged peptides are put in solution, they stick together and form a separate liquid phase, a process called complex coacervation. The liquid wraps around virus capsids, holding the virus material together like a burrito’s tortilla.
The Latest Updates from Bing News & Google News
Go deeper with Bing News on:
- Post-synthesis nanostructuration of BSA-Capsaicin nanoparticles generated by sucrose excipienton April 6, 2021 at 5:30 am
The stability of the BSA-capsaicin NPs was associated to complex capsaicin/amino acid/water, in which GLY/GLN, ALA/HIS, ARG, THR, TYR, and Iso/CYS amino acids are involved in the restructuration ...
- International journal of biological macromoleculeson April 4, 2021 at 5:01 pm
Facile and rapid in-situ synthesis of chitosan-ZnO nano-hybrids applicable in medical purposes; a novel combination of biomineralization, ultrasound, and bio-safe morphology-conducting agent.
- Ultrasonics sonochemistryon March 31, 2021 at 5:00 pm
Thermosonication as an alternative method for processing, extending the shelf life, and conserving the quality of pulque: A non-dairy Mexican fermented beverage. Ultrasound freeze-thawing style ...
- British Airways considers selling its headquarters after homeworking switchon March 19, 2021 at 1:38 am
Banking giant Lloyds said it would cut office space by 20% within three years, with HSBC aiming for a 40% reduction. The BA complex, Waterside, is near Heathrow Airport, west of London, and is also ...
- 'No silver bullet': torch relay struggles highlight hurdles for pandemic Olympicson March 19, 2021 at 1:08 am
The withdrawal by Akiyama and more than a dozen celebrities from the relay, which starts Thursday, underscores the challenges facing organisers of one of the world's most complex events, hosted by a ...
Go deeper with Google Headlines on:
Go deeper with Bing News on:
- UAE's largest 'freezer farm' to hold 11 million Covid vaccine doseson April 12, 2021 at 8:46 am
The Consortium has developed the largest ‘freezer farm’ in the UAE to boost storage and global distribution of vaccines. The farm complements the facility’s existing static capacity to store over 120 ...
- From checkout lines to vaccine lines: Vacant big-box stores get new life as mass vaccination siteson April 12, 2021 at 8:30 am
About 45,000 vaccines have been administered there since January ... The former Carson’s in Aurora was purchased by Storage of America about a year ago, and the company plans to turn it into a ...
- Vaccine seized from medical spa due to storage problemson April 12, 2021 at 8:12 am
... vaccine have been confiscated from a Colorado Springs medical spa after county health officials observed problems in vaccine storage on Friday, prompting the state health department to investigate ...
- COVID-19 vaccines in California: Everything you need to knowon April 12, 2021 at 8:09 am
The vaccine, made by Janssen, J&J's vaccine arm, is safe and effective, and it's considered flexible. It's a single dose, and it doesn't require special storage. The vaccine is authorized for people ...
- Arizona has paid Arizona State University more than $20 million for expenses running COVID-19 vaccine and test siteson April 12, 2021 at 6:30 am
They also have to manage storage, preparation and administration of the vaccine as well as all necessary supplies. Robert Fisher: The clues he left behind Here's the latest on tax deadlines, ...