Ionic liquids are salts that stay liquid at room temperature
| Photo Credit:
Getty Images
The quest for oral insulin — as an alternative to painful injections for millions of diabetics around the world — has long eluded success remained elusive.
Why?
Because of the body’s defence mechanism, which acts like a security guard who refuses to let in even a friend. The mucus lining of the gut regulates how substances enter the body by changing its flow and stickiness. This film is designed by nature to selectively absorb nutrients while blocking pathogens. In the process, gastrointestinal enzymes rapidly degrade insulin.
To get past this barrier, you need “smart carriers” to smuggle in drugs .
Recent studies suggest that ionic liquids (ILs) — salts that stay liquid at room temperature — can help by stabilising drugs and improving their ability to penetrate mucus.
A team from IIT-Guwahati (Nayanjyoti Kakati, Nabendu Paul, Saurabh Dubey, Jiwajyoti Mahanta, Anushka Raj Lakshmi, Tamal Banerjee, and Dipankar Bandyopadhyay) has gone a step ahead by using an ionic liquid — choline bicarbonate-maleic acid (CBMA) — as a smart carrier.
The IL promotes the aggregation of mucin — the main component of mucus — and disrupts its normal network structure, creating pathways for drugs. In simpler terms, it’s like clumping wires of a net together to enlarge some holes.
Becoming porous
At a deeper level, the chemistry is elegant. Mucus usually maintains an ordered structure because its negatively charged components (such as sialic acid residues) repel each other. The IL interacts with these negative sites, shielding them and reducing their repulsion. This allows mucin components to come closer to each other and aggregate — opening up alternative pathways through which drugs can slip in.
“The investigation sheds light on the interaction between choline bicarbonate–maleic acid-based ionic liquid and mucin polymer, offering valuable molecular-level insights for the development of oral and site-specific therapeutic drugs,” the researchers explain in their write-up for Advanced Science News.
In lab-simulated human intestines, the researchers showed that ILs enhance both the stability of bovine serum albumin (a standard model protein drug) and its ability to cross the mucus barrier — pointing to a promising strategy for oral protein drug delivery. Such an approach could let patients take protein-based medicines like insulin or therapeutic antibodies in pill form, rather than relying on injections.
The IIT-Guwahati work adds to a growing body of research on oral insulin. Another work in this direction is by a group of scientists, many of them from NSGM Institute of Pharmaceutical Sciences, who demonstrated a prolonged retention of insulin-loaded chitosan-coated solid lipid nanoparticles.
Since chitosan tends to stick to intestinal mucus, the insulin molecules that piggy-ride on it remain at the absorption site longer, giving them more opportunity to cross the mucus barrier and enter the body.
Published on August 25, 2025
