Is protein binding really so important? And what is plasma protein binding equilibrium dialysis?

Simply put, a drug’s efficiency is affected by the degree to which it binds; the less bound a drug is, the more efficiently it can traverse cell membranes or diffuse.

QUINTA-ANALYTICA uses plasma protein equilibrium dialysis and LC-MS / MS to determine this critical binding for its partners.

The highly effective equilibrium method sees Quinta use a device which has two chambers connected by a membrane with pores that allow only molecules up to a certain size to pass through it.  A sample of plasma or protein with analyte is then pipetted into one chamber, and a buffer is placed into the other.  Once the equilibrium has stabilized, due to the free movement of small molecules and ions across the membrane, its concentration in both chambers is then measured and corresponds directly to the amount of substance which is unbound to the proteins

For drugdevelopment it is critical to fully understand and measure this degree of protein binding of small molecules as it directly affects the rate of excretion of the preparation, in some cases, that can be as much as 95-99%, and in-turn, determines the drugs overall efficacy.

Contact us to learn more!

Additional News

  • 3 September 2026

    Quinta-Analytica Expands HPLC Fleet to Strengthen Flexibility and Capacity for Clients

    New Thermo Scientific Vanquish Core joins an HPLC fleet of around 50 systems

  • 7 August 2026

    Quinta-Analytica at CPHI Milan 2026 – Meet Us at Conscio Group Stand 6N25

    Meet Quinta-Analytica at CPHI Milan 2026 as part of the Conscio Group team at Stand 6N25. Discuss your clinical, bioanalytical and analytical projects with our experts and arrange a meeting in advance.

  • 15 July 2026

    Quinta-Analytica Awarded the EcoVadis Gold Medal

    Quinta-Analytica has been awarded the EcoVadis Gold Medal after achieving an overall sustainability score of 84 out of 100. The result represents a substantial increase from 68 points in the previous assessment and places the company in the 97th percentile globally.