Magnetic marker
monitoring

Magnetic Marker Monitoring (MMM) is a real time 3D imaging technique that can be used to track magnetically labelled objects in high temporal and high spatial resolution. Therefore, it represents a promising alternative to explore the behavior of solid dosage forms in the human GI tract without the application of radiation.

A dosage form can be tracked by MMM after it is marked as a permanent magnetic dipole by incorporating small amounts of ferromagnetic material (e.g. iron oxide) and subsequent magnetization. Thereby, the dosage form is labeled as the source of a well defined magnetic field. With the aid of established concepts for magnetic source localization, the 3D localization and orientation as well as the strength of the magnetic source can be reconstructed as a function of time. Therefore, it is also possible to gain quantitative information on the in vivo disintegration and erosion behavior of oral dosage forms.

Magnetic Marker Monitoring was used in the
past to answer various questions:

  • effect  of the volume of co-administered
    fluid on esophageal transit of capsules

  • effect of food on gastric transit

  • relationship between gastric localization
    and drug release behavior of extended
    release formulation

  • effect of the size of oral dosage forms on
    their GI transit behavior

Institute of Pharmacy

 UNiversity of Greifswald 

Germany