XPS Detects a Hidden Source of Contaminants in the Lab

Disposable elastic gloves are ubiquitous in scientific laboratories and are also widely used in many industries during handling of critical surfaces. Disposable gloves are typically made from nitrile or latex rubber and offer their users protection from various aqueous acids and bases, biological and medical fluids, organic solvents, and other potentially harmful substances. A second major use of disposable gloves is to protect manufactured products and analytical samples from contamination caused by the transfer of skin cells, oils, salts, cosmetics, hand lotions, or other residues resulting from contact with bare hands.

However, disposable gloves themselves can also be an overlooked potential source of contamination on handled surfaces. In addition to the primary polymer structure, many types of common laboratory gloves also contain a variety of inorganic salt additives used in the glove formulation. Silicone-containing mold-release agents that allow powder-free gloves to be easily stripped from the glove formers during fabrication may be present on glove surfaces. Post-forming processes such as chlorination are often used to oxidize the outer glove surface to reduce surface tackiness. Furthermore, the inner surface on disposable gloves may have polymeric surface coatings for improved donning properties. These inner coatings or other bulk glove components may permeate the glove material and segregate to the outer glove surface after exposure to certain solvents. Contact with solvents during a rinsing of items may also transfer glove components to the surfaces of those items.

Contamination resulting from surface residues on gloves can adversely affect materials used in industries where surface cleanliness is essential for optimum product performance and can also interfere with the analysis of samples depending on the specificity and sensitivity of the analytical technique. Therefore, it is important to know if the various components within a particular glove material are leached out by certain solvents or if manufacturing residues present on the surfaces of gloves are easily transferred to other materials.

X-ray photoelectron spectroscopy (XPS) is a qualitative and quantitative surface sensitive technique that can be used to evaluate the elemental and chemical surface composition of disposable gloves and to determine if contamination transfer occurs from gloves to other surfaces in a specific application. In this study, an XPS instrument was used to characterize the outer and inner surface compositions of a variety of common laboratory gloves. Changes in the surface composition of the gloves following exposure to several common laboratory solvents were also investigated. The transfer of surface components from the gloves to clean aluminum foil surfaces by light touching was also evaluated.

Read XPS Surface Characterization of Disposable Laboratory Gloves and the Transfer of Glove Components to Other Surfaces to learn about experiment details and results including XPS spectral images and tabulated analysis.