Evaluation of Drug Release Kinetics in Hydrogels
Owing to their tunable properties, controllable degradation, and ability to protect labile drugs, hydrogels are increasingly investigated as local drug delivery systems. They are applied to the enteral/oral administration route, local parenteral route, and the topical/transdermal route or the ocular route, which are usually more relevant for drug delivery in two dimensions. Evaluation of drug release kinetics is important to validate new drug delivery systems that are based on hydrogels. It can provide guidance for the development of hydrogel drug delivery systems and their clinical translation.
Evaluation Methods
Traditionally, evaluation of drug release kinetics includes investigations on in vitro drug release and release mechanisms. In the in vitro drug release test, drug-loaded hydrogel samples are immersed in a simulated release medium, which partly mimics physiological conditions in terms of pH, temperature, CO2 concentration, ionic strength, enzymatic presence/absence are other parameters. At every time point, supernatant samples are collected for drug concentration analysis. Upon quantification, a cumulative release curve is typically drawn, which corresponds to the amount or percentage of drug release over time. Then, different mathematical models are used to determine the in vitro drug release mechanism of a certain drug.
Alfa Chemistry has many methods for the detection and quantification of drugs released from hydrogel delivery systems. These methods include, but are not limited to, the following:
- HPLC-mass spectrometry (MS)
- Ultraviolet-visible (UV-Vis) absorbance
- Enzyme-linked immunosorbent assay (ELISA)
- High-performance liquid chromatography (HPLC)-UV
- Real-time quantitative polymerase chain reaction (RT-qPCR)
Mathematical models are beneficial to characterize and further explain release mechanisms of drugs. Fitting model equations we use include, but are not limited to, the following:
Where Mt is the total amount of drugs released at a time t, M∞is the total amount of drug cargo to be released, n is the diffusivity exponent, W0 is the initial amount of drugs in the drug delivery systems, Wt is the remaining amount of drugs in the drug delivery systems at time t, and k is the kinetic constant.
Our Advantages
- We offer evaluation services for drug release kinetics in a wide range of hydrogels, ranging from pure hydrogels to composite hydrogels.
- We have professional drug quantification methods to ensure the accuracy of drug release kinetics.
- We provide flexible and targeted technical support 24 hours a day, 7 days a week to reduce your time costs.
- We offer a complete analysis report, including method interpretation, data, result files and other information you need.
Service Process
Please kindly note that our products and services are for research use only.
