How important it is to maintain sink conditions during drug release studies from nanoparticles? What should be the concentration of pure drug and drug in nanoparticles in the buffer to start with? Is there a way to decide that? I have drug incorporated in polymeric nanoparticles.
It depends on you analytic in particular the quantification limiti. Use an a mount that allow you to quantify significantly. In my opinion sink conditions are essential for the reliability of the results.
It depends on you analytic in particular the quantification limiti. Use an a mount that allow you to quantify significantly. In my opinion sink conditions are essential for the reliability of the results.
Maintain the sink conditions is one of the most important factors during drug release stydies. You should be give the drug release rate profile of the pure drug both in the same concentration as is in nanoparticles and in the same experimental conditions..
I guess you already know what skin condition it is.
In case of hydrophobic drug, a few amount of surfactant is mixed in PBS or water because this drug can't be dissolve in water.
If you use hydrophobic drug, it's difficult to detect your drug using HPLC.
You just follow up another paper's method.
Well I think sink condition is only require when your external medium get saturated with released drug otherwise it is not significant. In many research paper you will find that sink condition was maintained but it may not have significant role in it. Quantity of you sample should be sufficient enough so that you can detect easily through your developed analytical method.
Hi, I think you have got your answer but would like to add a small point from our experience. In terms of concentration it would be better if you take minmum 200 microliter of 100-200 micromolar concentrated solution( even better if you take more concentrated) inside of the dialysis bag and you can dialyse it against 10 mL of respective buffer solution or you can even reduce this 10ml bufffer to 5 mL. After taking aliqotes at predetermined time points you can evaporate the buffer solution add DMSO to make the drug completely soluble followed by quantifying.
Thanks. Your suggestions are quite helpful. I found few papers where they said sink conditions are not absolutely necessary for nanoparticles.
If your drug is not soluble in aqueous media, sink condition is must...
Sink condition defined in USP as the volume of medium at least three times that required in order to form a saturated solution of drug substance. it is important to maintain sink conditions during the release. if sink condition is not applied and you got the drug not released, then how do you know that the no-release is because of the solution saturation (false no-release) of because of that the drug really has slow release from the nanoparticles.
if you have 10 mg of the drug and this 10 mg needs 1 ml medium to dissolve then sink condition is at least 3 ml. Note that sink condition is related to the release medium not only to your drug. For example, it might be 3 ml water is the sink condition for a drug and 10 ml PBS is the sink condition for the same drug.
- Badges
- Science topic
- Similar topics
- Chemistry
- Nanotechnology
- Nanoparticle Research