@article{HitzerBaeuerleDrieschneretal.2017,
  author    = {Hitzer, Patrick and B{\"a}uerle, Tim and Drieschner, Tobias and Ostertag, Edwin and Paulsen, Katharina and Lishaut, Holger van and Lorenz, G{\"u}nter and Rebner, Karsten},
  title     = {Process analytical techniques for hot-melt extrusion and their application to amorphous solid dispersions},
  series = {Analytical and bioanalytical chemistry},
  volume    = {409},
  journal   = {Analytical and bioanalytical chemistry},
  number    = {18},
  publisher = {Springer},
  address   = {Berlin, Heidelberg},
  issn      = {1618-2642},
  doi       = {10.1007/s00216-017-0292-z},
  pages     = {4321 -- 4333},
  year      = {2017},
  abstract  = {Newly developed active pharmaceutical ingredients (APIs) are often poorly soluble in water. As a result the bioavailability of the API in the human body is reduced. One approach to overcome this restriction is the formulation of amorphous solid dispersions (ASDs), e.g., by hot-melt extrusion (HME). Thus, the poorly soluble crystalline form of the API is transferred into a more soluble amorphous form. To reach this aim in HME, the APIs are embedded in a polymer matrix. The resulting amorphous solid dispersions may contain small amounts of residual crystallinity and have the tendency to recrystallize. For the controlled release of the API in the final drug product the amount of crystallinity has to be known. This review assesses the available analytical methods that have been recently used for the characterization of ASDs and the quantification of crystalline API content. Well established techniques like near- and mid-infrared spectroscopy (NIR and MIR, respectively), Raman spectroscopy, and emerging ones like UV/VIS, terahertz, and ultrasonic spectroscopy are considered in detail. Furthermore, their advantages and limitations are discussed with regard to general practical applicability as process analytical technology (PAT) tools in industrial manufacturing. The review focuses on spectroscopic methods which have been proven as most suitable for in-line and on-line process analytics. Further aspects are spectroscopic techniques that have been or could be integrated into an extruder.},
  language  = {en}
}
@article{BaeuerleOstertagDrieschneretal.2018,
  author    = {B{\"a}uerle, Tim and Ostertag, Edwin and Drieschner, Tobias and Lorenz, Anita and Mannhardt, Joachim and Lorenz, G{\"u}nter and Rebner, Karsten},
  title     = {Cleaning in Place Konzept zum Dauerbetrieb optischer Sonden in der Prozessanalytik der Polymerextrusion},
  series = {Zeitschrift Kunststofftechnik = Journal of plastics technology},
  volume    = {14},
  journal   = {Zeitschrift Kunststofftechnik = Journal of plastics technology},
  number    = {5},
  publisher = {Hanser},
  address   = {M{\"u}nchen},
  issn      = {1864-2217},
  doi       = {10.3139/O999.03052018},
  url       = {http://nbn-resolving.de/urn:nbn:de:bsz:rt2-opus4-19240},
  pages     = {348 -- 366},
  year      = {2018},
  abstract  = {Die kontinuierliche Erfassung von Qualit{\"a}tsparametern ist eine zunehmende Anforderung in der Polymerextrusion. Die optische Spektroskopie kann diese Anforderung erf{\"u}llen, da sie neben der Farbe weitere Parameter wie beispielsweise chemische Eigenschaften, Tr{\"u}bungsgrad oder Partikelgr{\"o}ße erfasst. Dabei werden f{\"u}r Inline-Messungen im Extruder optische Sonden eingesetzt. Im laufenden Betrieb bilden sich Ablagerungen auf den Sondenfenstern. Dieser Beitrag pr{\"a}sentiert ein neues Cleaning in Place Konzept, mit dessen Hilfe die Fenster auch w{\"a}hrend der Produktion ohne Unterbrechung gereinigt werden k{\"o}nnen. Auch die Kalibrierung der Messtechnik ist dabei m{\"o}glich. Das verhindert R{\"u}stzeiten und sichert eine kontinuierliche Inline-Messung.},
  language  = {de}
}