Gas-Phase Surface Engineering of Polystyrene Beads Used to Challenge Automated Particle Inspection Systems

Abstract

Container challenge sets, used in the qualification and validation of automated visible particle inspection systems in the parenteral drug industry, are prepared by seeding a single standardized polystyrene-divinylbenzene (PS-DVB) bead inside the commercial product to mimic foreign particulates. Due to its low surface energy and wettability, the bead adheres to container walls, hindering its detection by the motion based inspection system. The aim of this research is to modify the surface properties of the bead in such a way that it repulses the inner walls and stays in suspension inside the liquid product. The surface treatment consists of a photoinduced chemical vapor deposition (PICVD) process using syngas and UVC light. Following 2 treatment, newly grafted C-OH, C-O-C, C=O and COOH functional groups on the bead's surface are observed by XPS and FTIR spectroscopy, leading to an increase in the surface energy from 31 ± 1 to 65 ± 2 mJ/m 2 , and a corresponding zeta potential decrease from -38 mV to -61 mV.Finally, treated 100 µm, 200 µm and 500 µm PS-DVB beads suspended in water exhibit higher dispersion stability over time than untreated beads. These results show the potential of syngas PICVD to provide an effective solution to the stability issue of containers challenge sets for the validation of automated particle inspection systems, enabling significant savings of time and money to the parenteral drug industry.

Large-Scale Encapsulation of Magnetic Iron Oxide Nanoparticles via Syngas Photo-Initiated Chemical Vapor Deposition

“…Previously, our group studied the chemistry of syngas photo-initiated chemical vapor deposition (PICVD) on flat surfaces 40 , 41 , 52 and on particulates in a plug-flow configuration 42 , 53 – 55 . Herein, we adapt this process for use in a sub-pilot scale jet-assisted fluidized bed reactor (FB-PICVD) to coat large quantities of MIONPs (grams) in order to improve their dispersion and stability in non-polar (hydrophobic) media.…”

Kinetics, Chemistry, and Morphology of Syngas Photoinitiated Chemical Vapor Deposition

“…Very few researchers have attempted to study the photopolymerization of syngas components, 9,35 and most have focused on carbon monoxide photochemical reactions in the early Earth's atmosphere or with low wavelength VUV lamps. [35][36][37] Previously, our group demonstrated that syngas PICVD could be used to deposit thin films with various functionalities on copper substrates 9 and nanomaterials, [38][39][40][41] but the deposition mechanism and kinetics remain elusive.…”

<p>Hydrogels For Peptide Hormones Delivery: Therapeutic And Tissue Engineering Applications</p>

“…Also, pluronic micelles could concentrate the proteins at the particle surface and the stability and bioactivity of the proteins are higher than the aqueous phase 47. Polystyrene beads are also proposed to be safest particles for protein adsorption 48. Liposomes are reported as good proteins carriers because of their size, aqueous core, biocompatibility and biologically inertness, weak immunogenic nature, and limited toxicity that protect peptides in the GI 49,50.…”