Essity (Sweden)

ABSTRACTContact dermatitis is an inflammatory disease characterised by skin redness and swelling, oozing of fluid or pus and pain, caused by direct skin contact with an irritant or allergen. Its prevalence has skyrocketed worldwide, probably because human skin is in daily contact with an increasing gamut of irritants and allergens, which should require systematic surveillance. Large‐scale testing is feasible by using organotypic and in silico skin models, which are becoming commonplace in industry and academic labs. In this work, we summarise the literature on models of contact dermatitis and provide insights on advantages, limitations and options for improvement.

Cytokines are a large group of small proteins secreted by immune and non-immune cells in response to external stimuli. Much attention has been given to the application of cytokines’ detection in early disease diagnosis/monitoring and therapeutic response assessment. To date, a wide range of assays are available for cytokines detection. However, in specific applications, multiplexed or continuous measurements of cytokines with wearable biosensing devices are highly desirable. For such efforts, various nanomaterials have been extensively investigated due to their extraordinary properties, such as high surface area and controllable particle size and shape, which leads to their tunable optical emission, electrical, and magnetic properties. Different types of nanomaterials such as noble metal, metal oxide, and carbon nanoparticles have been explored for various biosensing applications. Advances in nanomaterial synthesis and device development have led to significant progress in pushing the limit of cytokine detection. This article reviews currently used methods for cytokines detection and new nanotechnology-based biosensors for ultrasensitive cytokine detection.

The main aims of this study were to describe the effects of incontinence pad composition on skin wetness, the skin/pad microclimate, and skin barrier function. We also evaluated the potential utility of our methods for future clinical investigation of absorbent pad design. Single-blind, quasi-experimental, open cohort design. Twenty healthy older volunteers (mean age = 72.8 years, SD = 5.8 years; 8 male and 12 female) tested 2 absorbent pad types, with acquisition layers of different compositions (A and B) applied to different sites on the volar aspect of the forearms. One type A pad served as control (A dry) versus 3 pad samples wetted with 3 volumes of saline (A 15 mL, A 35 mL, and B 15 mL). The study was conducted within the clinical laboratory of a university nursing research group in the United Kingdom. Skin barrier function was assessed by measuring transepidermal water loss (TEWL), stratum corneum (SC) hydration by corneometry, and skin surface pH using a standard skin pH electrode. Skin water loading (excess water penetration into the skin) was quantified by measuring TEWL and creating a desorption curve of the water vapor flux density. Calculating the area under the curve of the desorption curve to give skin surface water loss reflected excess water penetration into the skin. In a subgroup of the sample, the temperature and relative humidity (microclimate) at the interface between the skin and test pads were measured using a wafer-thin sensor placed between the skin and pad sample. Proinflammatory cytokine release from the SC was assessed using a noninvasive lipophilic film. The main outcome measures in this study were the differences in biophysical measurements of skin barrier function (TEWL, corneometer, and pH) before and after the application of the different pads. Mean ± SD baseline TEWL across all test sites was 10.4 ± 4.4 g/h/m. This increased to 10.6 ± 3.8 g/h/m at the control site, 15.3 ± 6.3 g/h/m for the A 15-mL pad, 15.3 ± 3.9 g/h/m for the A 35-mL pad, and 15.6 ± 3.2 g/h/m for the B 15-mL pad. The mean baseline skin surface pH was 5.9 ± 0.04; cutaneous pH increased to a mean of 6.1 ± 0.06 following all pad applications (P = .16). Mean SC hydration remained unchanged at the control site (A dry). In contrast, SC hydration increased following the application of all wetted pads. Target cytokines were detected in all samples we analyzed. The IL-1RA/IL-1α ratio increased following pad application, except for the wettest pad. Study findings suggest that absorbent pad design and composition, particularly the acquisition layer, affect performance and may influence skin health. Based on our experience with this study, we believe the methods we used provide a simple and objective means to evaluate product performance that could be used to guide the future development of products and applied to clinical settings.

The production of porous wheat gluten (WG) absorbent materials by means of extrusion processing is presented for the future development of sustainable superabsorbent polymers (SAPs). Different temperatures, formulations, and WG compositions were used to determine a useful protocol that provides the best combination of porosity and water swelling properties. The most optimal formulation was based on 50 wt.% WG in water that was processed at 80 °C as a mixture, which provided a porous core structure with a denser outer shell. As a green foaming agent, food-grade sodium bicarbonate was added during the processing, which allowed the formation of a more open porous material. This extruded WG material was able to swell 280% in water and, due to the open-cell structure, 28% with non-polar limonene. The results are paving the way towards production of porous bio macromolecular structures with high polar/non-polar liquid uptake, using extrusion as a solvent free and energy efficient production technique without toxic reagents.