Application of Scanning Electron Microscopy With Energy-Dispersive X-Ray Spectroscopy for Analyzing Ocular Surface Particles on Schirmer Strips

Abstract

Purpose To demonstrate the application of Scanning Electron Microscopy with Energy-Dispersive X-Ray Spectroscopy (SEM/EDS) for analyzing Schirmer strips for particle concentration, size, morphology, and type distribution. Methods A cross-sectional design was used. Patients were prospectively recruited from the Miami Veterans Affairs (VA) Healthcare System eye clinic and underwent a complete ocular surface examination. Size, type and chemical composition of PM Schirmer strips (from the left eye) were analyzed using SEM/EDS. Results Schirmer strips from all six patients showed particle loading, ranging from 1 to 33 particles, while the blank Schirmer strip that served as a control showed no particle loading. The majority of particles were coarse, with an average size of 19.7 μm (95% confidence interval 15 μm to 24.4 μm). All samples contained organic particles (e.g. pollen and mold), and five of the six samples contained non-organic particles. The non-organic particles were composed of silicon, minerals, and metals including gold and titanium. The size of aluminum and iron particles was ≥ 62 μm, whereas the size of two other metals, zinc and gold, were smaller, i.e. < 20 μm. Most metal particles were elongated compared to the organic particles that were round. Conclusion Although SEM/EDS has been extensively used in biomedical research, its novel application to assess the size, morphology and chemical composition of the ocular surface particles, offers an unprecedented opportunity to tease out the role of PM exposure in the ocular surface disease and disorder.

Gross, ultrastructural, and histological characterizations of pecten oculi of the glossy ibis (Plegadis falcinellus): New insights into its scanning electron microscope–energy dispersive X‐ray analysis

“…The present SEM–EDX analysis proposes that the biological plausibility of the element's analysis of the pecten oculi may be affected by the overdose of these elements, as it may lead to oxidative stress and physical eccentricity. With the inflammation state, similar findings were described by (Avula et al, 2017; Elghoul et al, 2021). Recently, we were required to understand the important roles of this element's analysis of the pecten oculi and describe their intense relationship with the visually active hours and the retina characterizations to know the visual strength of the different avian species in the various feeding styles.…”

Ultrastructural characterizations of the pecten oculi of the common ostrich (Struthio camelus): New insight to scanning electron microscope–energy dispersive X‐ray analysis

“…Our SEM–EDX findings suggested that the composition of the different elements of the pecten oculi may refer to the surrounding environmental conditions and the extent to which it contains airborne pollutants. Our SEM–EDX findings suggested that the biologic plausibility of the presence of these elements on the pecten oculi surface can influence the pecten oculi surface health as the overdose of these elements on the pecten oculi surface may lead to oxidative stress and physical abrasions, with inflammatory effects, similar to that reported by Avula et al (2017) and Wolkoff (2010). Future studies will be needed to complete this work, by comparison, the SEM–EDX findings of the pecten oculi with the retina to know more about the vision ability of the different or the same avian species in the different or the same environmental conditions.…”

Use of SEM/EDX methods for the analysis of ambient particulate matter adhering to the skin surface

“…With the exception of a few hazardous substances, data on the skin and systemic toxicity of most air pollutants are limited. The first step in understanding the potential health risks associated JEADV 2022, 36, 1376-1381 Table 1 Classification of particle groups based on their morphology and elemental composition [6][7][8] No Use of SEM/EDX methods for the analysis of ambient particulate matter adhering to the skin surface with skin exposure to AP is to identify relevant chemicals and quantitatively assess the exposure. 2 SEM-ED2X may provide new insights into the link between exposure to AP and APinduced skin damage.…”

“…Based on the literature review on elemental composition, 6,9–13 clustering rules and morphology, the particles were classified into major groups and subgroups that further defined their elemental composition, size, morphology and possible sources. Biogenic and unclassified particles were counted, with no additional chemical or geometrical specification.…”

“…However, it is widely acknowledged that mass alone is not the best metric for risk assessment 4 . This is especially true in the case of skin 5 and exposure assessment of mucous membranes 6 . Other particle properties such as particle surface area, size, number, and chemical composition can be linked to significant health risks.…”