I wasnt sure how the phrase the headline question really nor if this is the right place to ask it, but i'm primarily interested in the chemical synthesis aspect and the experience of chemists regarding this subject.
In the antimicrobial literature specific liposome or nano particle encapsulations of antibiotics have been shown over and over again to show immense potential for quite a long time by now, enhancing efficacy, pharmacokinetics while at the same time reducing toxicities. My question basically is, why is this not being used really? Advanced liposomes can be found in some vaccines for example and the likes of it. But we continue to pump e.g. Aminogylcosides like Gentamicin into people which while very effective against certain hard to treat organisms can fail due to 1. pharmacokinetic limitations (low intracellular penetration etc.) and 2. toxicity and damage.
Im not interested in the discussion about efficacy for treatment in people, as that wouldnt be on the subject of chemistry and that has already been shown, but rather what is it that makes it so hard about this being available? I found literature ranging from 20 years ago showing specific PH sensitive liposome encapsulations of Gentamicin vastly increased efficacy against gram negative intracellular infections in vitro and in vivo and immensely reduced toxicity towards human cells - yet its just nowhere to be seen.
Is it that hard to synthesize/make these compounds? Does it cost a castle made of gold to produce a single vial of it? I would like to hear chemists views on the complexity/cost ratio of the production if possible. I do no have an advanced background in chemistry but it is just hard for me to imagine it would take half the world to produce some specifically charged or ph sensitive liposomes - especially if the science on what and how has already been done.