You may have come across gelatin in the form of jelly or in chewy sweets, but did you know it is widely used across the research and healthcare industries too? From forming the soft capsules of medicines to perfecting the texture of ointments and cosmetics, gelatin is hidden in many products we use daily.

Gelatin is made by slowly heating collagen, a protein responsible for tissue elasticity (stretchiness) that is taken from the skin, tendons, ligaments and bones of pigs, cows, fish, birds and even rats. When heated for long periods of time, collagen becomes the thick, jelly-like substance known as gelatin.

The global demand for gelatin is estimated to be around 650 kilotons a year, the majority of which is made from pig or cow skin. This production is estimated to use an unbelievable 65 million animals each year, but is there a better, more ethical way?

Animal-free alternatives for research

Plant-based setting agents such as pectin or Carrageenan are long-established alternatives to gelatin in food, providing an easy swap to make foods vegetarian or vegan. However, making the switch in the research industry is not quite so easy.

Gelatin is favoured in many types of research experiments because its consistency can be changed by temperature, so it is regularly used to grow cells and carry out various experiments. However, as this is an animal-derived product, we don’t know how it might affect the results of experiments using human cells.

Artificial gelatins are available to buy on the market, however the ability to respond to temperature can be difficult to mimic in a synthetic material. In addition, most synthetic gelatins are made using animal-derived base products which may still interfere with experimental results, so there is need to create a completely animal-free version.

ThermoPIGs

Dr Sam Aspinall at the University of Hertfordshire is developing new animal-free synthetic gelatins called Thermoresponsive Polymers Imitating Gelatins – or ThermoPIGs, to replace animal-derived gelatins in research and other applications.

ThermoPIGs are made using gel-like substances called polymers. Importantly, they are thermoresponsive (responsive to temperature) in the same way as animal-derived gelatin, with the potential to offer a direct replacement in cell culture and experiments.

Various synthetic gelatin formulations will be tested to see which ones act most similarly to animal-derived gelatin, including their ability to form stiff gels at room temperature and melt when heated. In addition, as they don’t contain animal-derived biomaterials, ThermoPIGs offer many other benefits including a lower risk of bacterial contamination, more consistent and predictable results, and the ability to carry out experiments using only animal-free materials that can be more easily translated into clinical research.

ThermoPIGs can respond to temperature changes in the same way as gelatin, changing from a gel at lower temperatures to a liquid at higher temperatures, making them a favourable alternative.

Improving research quality

Aside from replacing gelatin use when growing cells, Dr Aspinall aims to use ThermoPIGs to transport cells at room temperature, which could have a significant positive impact on the research industry. Currently, cells are frozen when they’re shipped to researchers from suppliers, but this can change their properties, make them less viable and sometimes cause misleading experimental results.

Dr Aspinall will test whether ThermoPIGs can keep cells stable for days at a time and therefore could be used for shipping human cells at room temperature. If the cells remain stable and viable, this could remove the need to freeze cells for shipping, leading to better quality research with more reliable results.

Impact and future goals

ThermoPIGs are an innovative product with the potential to replace gelatin use across several industries, improving research quality while reducing the number of animals used in its production each year.

Following further testing of the most promising candidate formulas, Dr Aspinall aims to increase production capacity and commercialise the product for large-scale distribution, increasing its awareness and promoting its use around the world.