KIT | KIT-Bibliothek | Impressum | Datenschutz

Influence of Refractive Index Differences on the Signal Strength for Raman-Spectroscopic Measurements of Double Emulsion Droplets

Hufnagel, Thomas ; Rädle, Matthias ; Karbstein, Heike P. 1
1 Institut für Bio- und Lebensmitteltechnik (BLT), Karlsruher Institut für Technologie (KIT)

Abstract:

Double emulsions show great potential for encapsulating active substances and protecting them against external influences. However, they tend to become unstable during storage. Research on double emulsions, therefore, focuses on maintaining their microstructure during their shelf life. Optical measurement methods, such as Raman spectroscopy, have hardly been used to date to analyze the microstructure of double emulsions, mainly due to multiple scattering effects. This study investigates the influence of refractive index matching of double emulsion phases by measuring the Raman signal strength of the inner water phase for different refractive index combinations. Ammonium nitrate and glycerol are added to the inner and outer water phase, respectively, to change the refractive indices of both phases. Additionally, polyvinyl alcohol serves as an emulsifier in the outer water phase. The oil phase consists of silicone oil and Dowsil Resin XR 0497 as the emulsifier. The refractive index of the oil phase is kept constant. For individual phase boundaries of single droplets, the refractive index matching plays a minor role. However, if there are many droplets with correspondingly numerous phase boundaries, which leads to multiple scattering during the measurement, the matching has a significant influence on the signal strength of the inner phase. ... mehr


Verlagsausgabe §
DOI: 10.5445/IR/1000151834
Veröffentlicht am 24.10.2022
Originalveröffentlichung
DOI: 10.3390/app12189056
Scopus
Zitationen: 7
Web of Science
Zitationen: 7
Dimensions
Zitationen: 7
Cover der Publikation
Zugehörige Institution(en) am KIT Institut für Bio- und Lebensmitteltechnik (BLT)
Publikationstyp Zeitschriftenaufsatz
Publikationsjahr 2022
Sprache Englisch
Identifikator ISSN: 2076-3417
KITopen-ID: 1000151834
Erschienen in Applied Sciences
Verlag MDPI
Band 12
Heft 18
Seiten Art.-Nr.: 9056
Vorab online veröffentlicht am 08.09.2022
Schlagwörter double emulsion, Raman spectroscopy, refractive index matching, multiple scattering, glass capillary device, microfluidic, Fresnel’s formula, multiple linear regression
Nachgewiesen in Web of Science
Scopus
Dimensions
Relationen in KITopen
KIT – Die Forschungsuniversität in der Helmholtz-Gemeinschaft
KITopen Landing Page