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HYPOTHESIS: Porous magnetic silica beads are promising materials for biological and environmental applications due to their enhanced adsorption and ease of recovery. This work aims to develop a new, inexpensive and environmentally friendly approach based on agglomeration of nanoparticles in aqueous droplets. The use of an emulsion as a geometrical constraint is expected to result in the formation of spherical beads with tunable composition depending on the aqueous phase content. EXPERIMENTS: Magnetic silica beads are produced at room temperature by colloidal destabilization induced by addition of CaCl2 to a water-in-oil emulsion containing SiO2 and Fe3O4 nanoparticles. The impact of the salt concentration, emulsification method, concentration of hydrophobic surfactant as well as silica content is presented in this paper. FINDINGS: This method enables the production of spherical beads with diameters between 1 and 9 µm. The incorporation of magnetic nanoparticles inside the bead's structure is confirmed using Energy Dispersive X-ray spectrometry (EDX) and Scanning Transmission Electron Microscopy (STEM) and results in the production of magnetic responsive beads with a preparation yield up to 84%. By incorporating the surfactant Span 80 in the oil phase it is possible to tune the roughness and porosity of the beads.
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Wound contact layer (WCL) dressings are intended to protect tissue during the healing process. A randomised controlled trial was undertaken to compare 2 such dressings. Outpatients with acute wounds were randomly allocated to treatment with either a soft silicone-coated WCL (intervention group, n = 59) or a lipidocolloid-impregnated WCL (control group, n = 62). At the first dressing removal (day 3), 89.8% of patients in the intervention group experienced non-painful dressing removal (defined as a pain rating <30 mm on a 100 mm visual analogue scale), compared with 73.6% of patients in the control group (P = .017) (per protocol population). At day 21, wounds were considered as healed in 66.1% of patients in the intervention group compared with 43.5% in the control group (P = .012) (intention-to-treat population). Both dressings were well tolerated and rated highly in terms of in-use characteristics, although the soft silicone-coated WCL was rated significantly higher than the lipidocolloid-impregnated WCL in terms of its ability to remain in place (P= .016). The results indicate that the soft silicone-coated WCL is suitable for the management of acute wounds as it can minimise dressing-associated pain and support healing.