caa a22 4500 445312009 CHVBK 20180317142633.0 cr unu---uuuuu 170323e20110901xx s 000 0 eng 10.1007/s11095-011-0448-z doi (NATIONALLICENCE)springer-10.1007/s11095-011-0448-z Turbidity Spectroscopy for Characterization of Submicroscopic Drug Carriers, Such as Nanoparticles and Lipid Vesicles: Size Determination [Elektronische Daten] [Mustafa Elsayed, Gregor Cevc] ABSTRACT: Purpose: To apply UV/Vis spectrometry for characterization of submicroscopic drug carriers, such as nanoparticles and lipid vesicles. Methods: We first investigated theoretically, within the framework of the Rayleigh-Gans-Debye approximation (RGDA), parameters affecting turbidity spectrum, τ(λ), of nanosized light scatterers. We then analyzed, within the framework of the RGDA, experimental turbidity spectra (λ = 400-600nm) of extruded unilamellar vesicle (70nm ≤ 2r ≤ 110nm) suspensions to derive vesicle size, using dynamic light scattering results for comparison. We similarly studied the preparations polydispersity and lamellarity and monitored vesicle size changes. Results: Turbidimetry suffices for accurate, fast, and viscosity-independent characterization of submicroscopic particles. Analysis of turbidity spectra, or more precisely wavelength exponent spectra (derivatives of logarithmic turbidity spectra), yielded similar average radii (r = 54.2 ± 0.2nm; 46.0 ± 0.2nm; 35.5 ± 0.1nm) as dynamic light scattering (r = 55.9 ± 1.5nm; 46.1 ± 0.4nm; 36.1 ± 0.4nm). Both methods also revealed similar suspension polydispersity and cholate-induced vesicle size changes in a few nanometer range. Conclusion: Despite its experimental simplicity, the widely accessible turbidimetric method provides accurate size values and is suitable for (continuous) monitoring size stability, or sameness, of submicroscopic drug carriers. Springer Science+Business Media, LLC, 2011 continuous monitoring nationallicence drug delivery nationallicence light scattering nationallicence product quality control nationallicence size distribution nationallicence Elsayed Mustafa IDEA AG, Frankfurter Ring 193a, 80807, Munich, Germany aut Cevc Gregor Advanced Treatments Institute, Tassilostr. 3, 82131, Gauting, Germany aut Pharmaceutical Research Springer US; http://www.springer-ny.com 28/9(2011-09-01), 2204-2222 0724-8741 28:9<2204 2011 28 11095 https://doi.org/10.1007/s11095-011-0448-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11095-011-0448-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Elsayed Mustafa IDEA AG, Frankfurter Ring 193a, 80807, Munich, Germany aut NATIONALLICENCE 700 1- Cevc Gregor Advanced Treatments Institute, Tassilostr. 3, 82131, Gauting, Germany aut NATIONALLICENCE 773 0- Pharmaceutical Research Springer US; http://www.springer-ny.com 28/9(2011-09-01), 2204-2222 0724-8741 28:9<2204 2011 28 11095 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer