JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY, cilt.76, 2022 (SCI-Expanded)
Diabetes is still one of the leading causes of death worldwide. According to the World Health Organization, around 1.5 million people worldwide died due to diabetes in 2019. It is estimated that 463 million people are living with diabetes all over the world. Many successful studies reported that splendid antihyperglycemic drugs can be developed with the help of new technologies and they can effectively deliver the active molecules by nanocarriers. In particular, recent studies show that some nanostructures namely quantum dots can be taken orally and their blood glucose-reducing effects are noteworthy. In our previous studies insulin was found to lower blood glucose levels when administered orally in liposome formulations. This study, it was aimed to examine whether carbon quantum dots can be used to transport insulin through the oral route and whether can they protect insulin from gastrointestinal enzymes as they can easily pass through both cell membranes and biological walls. It is also aimed to reveal the mechanism by which this effect occurs.First off, fluorescent composite carbon quantum dots (N-doped) smaller than 10 nm were prepared with L- cysteine, treated with insulin, and decorated with poly ethylene glycol 3350 and methylcellulose for oral administration. As a result, these developed carbon quantum dots were administered orally to diabetic animals and their blood sugars were reduced by about 60% within 5 h.It was then found that their blood levels were similarly reduced when prepared composite carbon quantum dots were orally administered alone to rats. It is found that although they do not contain any insulin, they in-crease the cellular response and metabolism in the mitochondria, causing glycolysis and thus having an anti -hyperglycemic effect when they are given orally. This is the first study in the literature that evaluated that the fine structure of the carbon quantum dot is important for having an antihyperglycemic effect and the l-quantum dot structure will be more effective.