Physicochemical parameters give valuable information about the drug-likeness of the molecules. Solubility and lipophilicity are key factors when considering compound absorption and distribution and such data provides valuable advice, e.g., for preparing pharmaceutical formulations for in vivo PK studies.
Is it advisable to consider the physicochemical properties before stepping further into ADME assays as these parameters not only predict the behaviour of the compound in in vivo but also help in planning reliable test conditions for further in vitro assays.
Plasma protein binding is a crucial ADME parameter as it markedly affects distribution and elimination. Plasma protein binding of small molecules is most often studied with rapid equilibrium dialysis (RED) using plasma from various species. Cut off value of the dialysis membrane is a limiting factor of the RED method and thus larger molecules, such as peptides, can be studied by cross filtration method. Third approach for the determination of plasma protein binding is high-sensitivity binding assay, which could be considered e.g. for poorly soluble or highly bound compounds. In addition to plasma protein binding, binding to different tissues can be determined by rapid equilibrium dialysis, when needed.
It is worth noting that in cases where affinity of the compound towards red blood cells is high, the use of plasma samples in PK calculations will have limitations and PK parameter determination from whole blood should be considered as well as evaluating blood to plasma partitioning.
In addition to early ADME studies, Admescope´s service portfolio contains several assays which can help you through preclinical development and safety metabolism evaluation in clinical phase. Please contact us for more information.
If the ADME properties of you compound appear unsatisfactory, please don´t forget the possibility to optimize your compound with the help of the drug discovery services from our mother company Symeres. Together with Symeres we can provide integrated drug discovery and development services.
Admescope´s customer satisfaction continues to be top-notch
We recently conducted our annual customer satisfaction survey and asked our clients to review our performance during the year 2021.
Quality, competence, flexibility, customer communication and turnaround time were measured in the survey. Admescope continues to be very highly rated by the customers. Our average score stayed in excellent 4.5/5.
We are honoured by your feedback and wish to thank everyone who spent their time to answer the questionnaire.
To express our appreciation for your valuable contribution we donated to UNICEF for each completed satisfaction survey response. If you have any questions regarding the conducted survey, please contact Head of Business Development Dr Miia Kovalainen.