Nele Hempel

Nele Hempel

PhD fellow

- solid state pharmaceutics

- amorphous form

- stability

- amorphous solid dispersion

- BCS Class II

Current research

Investigation of the fundamental aspects of microwave activation of pharmaceutical oral dosage forms:

Up to 90% of new drug enteties show poor aqueous solubility, leading to little and fluctuating bioavailability and thus fail marketing. New strategies in drug formulations have to be found to overcome the poor solubility in order to make use of these life-saving drugs. As the amorphous form of a drug shows higher solubility and higher dissolution rates due to higher molecular motionas its crystalline counterpart, this can be used as one approach. Physical instability though restricts the use of the amorphous form and asks for formulation solutions for stabilisation. Amorphous solid dispersions are glass solutions that are formed with polymers, such as PVP. Even though stabilisation increases only few products are marketed as of today, as long-term stability remains challenging. Microwave activation can be used to form in situ amorphous solid dispersions immediately before administration, thus circumvent those stability problems. The amorphous solid dispersion will be generated using microwave energy prior to administration from a solid dosage form- a process called in situ amorphization. The project is set to evaluate parameters, such as the role of water, the frequency of the microwave, the polymer and the drug (including their physicochemical properties as well as their interactions), to determine their impact on a successful in situ amorphization using microwave energy. 

Selected publications

  1. Published

    The Influence of Temperature and Viscosity of Polyethylene Glycol on the Rate of Microwave-Induced In Situ Amorphization of Celecoxib

    Hempel, Nele-Johanna, Dao, T., Knopp, Matthias Manne, Berthelsen, Ragna & Löbmann, Korbinian, 2021, In: Molecules. 26, 1, 8 p., 110.

    Research output: Contribution to journalJournal articleResearchpeer-review

  2. Published

    The Use of Glycerol as an Enabling Excipient for Microwave-Induced In Situ Drug Amorphization

    Hempel, Nele-Johanna, Morsch, F., Knopp, Matthias Manne, Berthelsen, Ragna & Löbmann, Korbinian, 2021, In: Journal of Pharmaceutical Sciences. 110, 1, p. 155-163 9 p.

    Research output: Contribution to journalJournal articleResearchpeer-review

  3. Published

    The influence of drug and polymer particle size on the in situ amorphization using microwave irradiation

    Hempel, Nele-Johanna, Knopp, Matthias Manne, Berthelsen, Ragna, Zeitler, J. A. & Löbmann, Korbinian, Apr 2020, In: European Journal of Pharmaceutics and Biopharmaceutics. 149, p. 77-84 8 p.

    Research output: Contribution to journalJournal articleResearchpeer-review

  4. Published

    Convection-Induced vs. Microwave Radiation-Induced in situ Drug Amorphization

    Hempel, Nele-Johanna, Knopp, Matthias Manne, Berthelsen, Ragna & Löbmann, Korbinian, 2020, In: Molecules. 25, 5, 7 p., 1068.

    Research output: Contribution to journalJournal articleResearchpeer-review

  5. Published

    Characterising glass transition temperatures and glass dynamics in mesoporous silica-based amorphous drugs

    Kissi, E. O., Ruggiero, M. T., Hempel, Nele-Johanna, Song, Z., Grohganz, Holger, Rades, Thomas & Löbmann, Korbinian, 1 Jan 2019, In: Physical Chemistry Chemical Physics. 21, 35, p. 19686-19694 9 p.

    Research output: Contribution to journalJournal articleResearchpeer-review

  6. Published

    A fast and reliable DSC-based method to determine the monomolecular loading capacity of drugs with good glass-forming ability in mesoporous silica

    Hempel, Nele-Johanna, Brede, K., Olesen, N. E., Genina, Natalja, Knopp, Matthias Manne & Löbmann, Korbinian, 18 Apr 2018, In: International Journal of Pharmaceutics. 544, 1, p. 153-57

    Research output: Contribution to journalJournal articleResearchpeer-review

ID: 196980904