Dissolution Rate and Intrinsic Dissolution using the SPA™ Method

SPA™ Dissolution Rate Assay Service

Dissolution Rate or Intrinsic Dissolution Rate (IDR) is a measure of the rate of dissolution of a pure sample where the conditions of surface area, temperature, agitation/stirring speed, medium pH, and ionic strength are all kept
constant.  IDR is important during the development of new drug molecules as it is possible to predict potential problems using very small quantities of material. It has applications in evaluating drug solubility in accordance with the biopharmaceutics classification system (BCS), comparison of the dissolution rate during salt selection or polymorph screening to choose the best candidate, and setting specifications for particle size in order to achieve complete dissolution of the required dose within the typical gastrointestinal transfer time. IDR screening can be applied to promising drug candidates to guide early development efforts to improve a drug’s in vivo characteristics.

Dissolution Rate Earlier

<1mg of API for Dissolution Assays

Data During Polymorph Screen

Actual Microscale Dissolution

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All FREE Whitepapers are available to download today:

SPA™ Technology Whitepaper

Chemistry Agnostic Whitepaper

UPDATED! Comparison SPA™ Assay vs Shake Flask Whitepaper

SPA™ Assisted Modelling Whitepaper.

Why SPA™ Dissolution Rate?

Quickest, Earlier IDR Data Ever!
The accuracy of models fed with real experimental data increases considerably. 

IDR data for generated alongside SPA Solubility Data, a powerful tool for Polymorph screens.   

Using the SPA method
Short Assay Time

The surface area determined for each sample

Constant flow

Buffers used
USP buffers ranging from pH 1.0 up to pH 12.0

Process solvents 

Biorelevant buffers: FaSSGF, FeSSIF, FaSSIF

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Results are fully reported to the client normally within 10 days of the sample arriving in Helsinki, faster turnarounds are available for time-critical projects.

Other Services

SPA™ Solubility Assay

SPA™ solubility is measured from less than 100 μg of solid sample

SPA™ Developability Profile

The development route of an API  and pKa from solubility profile, using the SPA™ Method



Polarized Light Microscopy Service, determine if your sample is crystaline or amorphous