Sirius inForm

Powerful instrument for bio-relevant dissolution and solubility analysis of formulations and dosage forms.

Features and Benefits




Robotics. Fully automated x, y and z axis on both arms.

Automation allows you to run complicated assays that would be hard to do manually.

Enclosure. The instrument is built inside an enclosure that prevents accidental contact with moving parts.

Protects robotics from damage. Enhances safety for users.

Platform. The platform can be modified for customised installations, e.g. novel spectroscopy.

Versatility. Opportunity to introduce novel assays.



Dissolution. Dissolution with temperature and pH control, ability to dilute and add biorelevant reagents (e.g. FaSSIF), and to remove aliquots during experiment.

Allows dissolution to be studied under conditions that mimic those found in the body and environment.

Biphasic dissolution. As above, with lipid phase added.

Makes it possible to run dissolution in small volumes under sink conditions. Provides a way to model passive absorption and  ion-pair partitioning. Provides good discrimination between formulations.

pH-metric dissolution. Uses pH-stat to measure dissolution kinetics through pH control. Useful for ionisable systems when solution is less that 2 units away from pKa.

Makes it easy to see how dissolution rates are affected by ionisation. Method is unaffected by turbidity.

Lipolysis. Study digestion of lipid-based formulations; measure API released during digestion.

A way to characterise lipid-based formulations in in vitro experiments.

Supersaturation, precipitation. Controlled supersaturation experiments by pH-shift and solvent quench methods. Determine induction times and precipitation rates.

A good way to investigate the effectiveness of formulations for enhancing solubility by stabilising amorphous forms.

pKa. Measure aqueous pKa, and pKa in presence of media ingredients. pH-metric and pH-UV methods provided.

Useful for measuring molar extinction coefficients (MECs), which are required for determining concentrations and weights released in dissolution assays.

Solubility. Measure solubility of ionisable drugs by CheqSol and Curve-Fitting methods. Extrapolate a pH-solubility profile.

Sirius methods provide valuable insights, such as learning whether compounds precipitate in  LLPS form with the potential for solubility enhancement.



Assay conditions. Assays are performed in solution, 20 - 80 mL. Solutions prepared in vials via automated dispensers and temperature-controlled between 10 - 70°C.

Large enough for high-accuracy measurement. Small enough for robotics and to conserve reagents and samples.

Sample introduction - solids. The instrument is supplied with a range of baskets, boats and tablet disc holders. Samples awaiting analysis are placed in a rack. They are picked up automatically and lowered into solution at the start of UV data collection.

Versatile - samples can be powders, granules or whole dosage forms. Data can be collected from time = 0.

Tablet press. Sirius inForm is supplied with hand-operated screw press to make tablets of API powder with 3, 6 or 8 mm diameter.

Tablets dissolve more slowly than powders. No problems with turbidity. Dissolution from tablets is used to determine IDR.

Sample introduction -liquids. Liquid samples can be added automatically. Aliquots (10μL-5mL) are aspirated from 2 or 4 mL vials via a septum-piercing needle and dispensed art the start of UV data collection.

Versatile - samples can be solutions, suspensions and low viscosity lipid based formulations. Data can be collected from time = 0.

Sample extraction and filtration. Aliquots of dissolution media can be removed during experiments and stored in vacuum-filtered 96-well plate for ex-situ analysis, e.g. by HPLC.

A good way to measure concentrations when solutions are too turbid for in-situ UV.