Dear Muhammad Jawad, you can use HPLC method to evaluate drug release from nanoparticles, but also to determine the drug encapsulation efficiency. We have used this method for one of our study, maybe it will be useful for yours too. It's not in my field, but you can find out a lot by searching the literature or maybe you have someone in your lab that is working in this domain.

Usually UV Vis spectrometry is used to note the absorbance of the PBS solvent in which the nanoparticles are suspended but my question is how to we determine the released amount through drug release kinetics and to apply those equations to identify released amount percentage with time

For this, following steps should be followed:

1) Add measured quantity of nanoparticles in PBS at a specific temperature.

2) At regular intervals of time, take some aliquots of PBS containing the released drug and go on measuring it's absorbance using UV-Vis spectroscopy.

3) From absorbance values, calculate the amount of drug released by using the Beer-Lambert formula.

4) As far as the kinetic models are concerned, you can use First Order Kinetic Model, Higuchi's model, etc. Go through the following papers that will definitely help you to solve your queries:

a) https://doi.org/10.1016/j.foodchem.2021.131925

b) https://doi.org/10.1016/j.molliq.2023.122243

c) https://doi.org/10.1021/acsfoodscitech.3c00032

d) https://doi.org/10.1016/j.colsurfa.2024.134876

Best wishes

How can you troubleshoot if your drug is precipitating on the surface of the dialysis membrane?

Dear Dr, please read this answer from my published paper about improving bioavailability of the hydrophobic drug acyclovir..

In Vitro Drug Release Studies: in vitro ACV release studies were carried out using the dried discs of ACV-loaded nanogels with the same dimensions, shape, and weight but different polymeric matrices. The prepared samples were inserted, each one in a solution containing 50 mL of simulated gastric fluid SGF, pH 1.2, for 2 h, followed by simulated intestinal fluid SIF, pH 7.4, for 10 h, within a magnetic stirrer. About 2 mL of release medium was removed manually at 60 min intervals for 12 h and replaced by the same volume of fresh buffer. The assay of ACV concentration in the eliminated supernatant was performed by a UV-spectrophotometer at λmax 256 nm. The cumulative release % was evaluated using the following eq

% cumulative release = At / A actual × 100

where At is the amount of ACV released from hydrogels at time t and Aactual is the actual amount of ACV loaded in nanogels.

Also the release mechanism using distinctive kinetic models are mentioned here in this reference

Article Hyaluronic Acid-Based pH-Sensitive Nanogel: Synthesis, Chara...