title: Measuring Subvisible Particles in Protein Formulations Using a Modified Light Obscuration Sensor with Improved Detection Capabilities.
abstract: Although light obscuration is the "gold standard" for subvisible particle measurements in biopharmaceutical products, the current technology has limitations with respect to the detection of translucent proteinaceous particles and particles of sizes smaller and around 2 μm. Here, we describe the evaluation of a modified light obscuration sensor utilizing a novel measuring mode. Whereas standard light obscuration methodology monitors the height (amplitude) of the signal, the new approach monitors its length (width). Experimental evaluation demonstrated that this new detection mode leads to improved detection of subvisible particles of sizes smaller than 2 μm, reduction of artifacts during measurements especially of low concentrations of translucent protein particles, and higher counting accuracy as compared to flow imaging microscopy and standard light obscuration measurements.
authors.affiliation: §Department of Pharmaceutical Sciences, Division of Pharmaceutical Technology, University of Basel, 4056 Basel, Switzerland.
authors.forename: Anacelia
authors.initials: A
authors.lastname: Ríos Quiroz
authors.affiliation: §Department of Pharmaceutical Sciences, Division of Pharmaceutical Technology, University of Basel, 4056 Basel, Switzerland.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Québatte
authors.forename: Fabian
authors.initials: F
authors.lastname: Stump
authors.forename: Christof
authors.initials: C
authors.lastname: Finkler
authors.affiliation: §Department of Pharmaceutical Sciences, Division of Pharmaceutical Technology, University of Basel, 4056 Basel, Switzerland.
authors.forename: Joerg
authors.initials: J
authors.lastname: Huwyler
authors.forename: Roland
authors.initials: R
authors.lastname: Schmidt
authors.forename: Hanns-Christian
authors.initials: HC
authors.lastname: Mahler
authors.forename: Atanas V
authors.initials: AV
authors.lastname: Koulov
authors.forename: Michael
authors.initials: M
authors.lastname: Adler
mesh_terms: D000818:Animals; D002417:Cattle; D008027:Light; D009391:Nephelometry and Turbidimetry / Q000295:instrumentation; D010316:Particle Size; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D012710:Serum Albumin, Bovine