While many drugs are able to treat some condition or disease exceedingly well, it may be very hard to get that drug to the part of the body where it is most effective. Moreover, releasing a drug in a controlled fashion is another important factor for many medications. When developing drug ferrying particles, researchers end up doing a lot of testing of each batch of particles to see how well they work with a given drug. This is a slow and meticulous process that could benefit from a way to screen out as many of the potential candidate particles as possible.
Researchers at Eindhoven University of Technology and Utrecht University in The Netherlands have now come up with a method of predicting how well a drug works with a common way of encapsulating drugs, as well as how to program the release mechanism to achieve a desired effect. The method will make it easier to narrow down the necessary experiments that will be necessary to conduct to make sure a given encapsulation technique works as desired.
Many, if not most, drugs are hydrophobic, so they’re often encapsulated inside packages that are hydrophobic on the inside and hydrophilic on the outside. When these packages, called micelle, are inside the body and are ready to release the drug they open up, so that their hydrophobic parts point toward the inside and hydrophilic part toward the outside, forming a flower-like structure. The actual drug nestles inside this micelle, but its location within the micelle is important in regards to how fast it will seep out and into the body once the micelle opens up.
The Dutch researchers developed a way of using a novel dye to quickly see how well a micelle releases it in a given solution. The dye can be manipulated easily to study different approaches and to design drug carrying microcapsules accordingly.
Some details from the study abstract in journal Langmuir:
Using Scheutjens–Fleer self-consistent field (SF-SCF) computations, we found that solubilization is regulated by a complex interplay between enthalpic and entropic contributions and that the spatial distribution can be controlled by the concentration and solubility of the guest compound in the dispersion medium. Upon solubilization, a characteristic change in size and mass of the micelles is predicted. This can be used as a fingerprint to indirectly assess the spatial distribution. Based on these findings, we developed two experimental protocols to control and assess the spatial distribution of lyophobic compounds within block copolymer micelles.