Resorcinol–formaldehyde aerogel coating for in‐tube solid‐phase microextraction of estrogens

Abstract

Resorcinol-formaldehyde aerogel coating was in situ prepared on the surface of basalt fibers. The aerogel coating is uniformly modified onto basalt fibers, and it is very porous according to the characterization by using scanning electron microscopy. An extraction tube was prepared for in-tube solid-phase microextraction by placing the aerogel-coated basalt fibers into a polyetheretherketone tube. To evaluate the extraction performance toward five estrogenic compounds, the tube was connected with high performance liquid chromatography, the important extraction and desorption conditions were investigated. An online analytical method for detection of estrogens was developed and presented low limits of detection (0.005-0.030 µg/L), wide linear ranges (0.017-20, 0.033-20, and 0.099-20 µg/L), good linearity (r > 0.9990), and satisfactory repeatability (relative standard deviation < 2.7%). The method was successfully applied to detect trace estrogens in real water samples (bottled pure water and bottled mineral water), satisfactory recoveries were ranged from 80 to 125% with two spiking levels of 2 and 6 µg/L. K E Y W O R D Saerogels, estrogens, high performance liquid chromatography, online analysis, solid-phase microextraction

Cryoaerogels and Cryohydrogels as Efficient Electrocatalysts

“…[13][14][15][16] For that, especially thin films or coatings from these materials on electrodes are of special interest. [17][18][19] These materials are mainly prepared by drop-casting (and subsequent drying) of a slurry on the electrode that is consisting of the aerogel, solvents, and a binding substance such as Nafion. [20][21][22][23] However, the monolithic structure is destroyed by mixing the slurry beforehand, so that the resulting coating consists of smaller aerogel fragments, that are covered and connected by the binding material.…”

Structural Diversity in Cryoaerogel Synthesis

“… 8 − 10 Owing to the good accessibility of the surface, thin films or coatings from these materials experience an increasing interest. 11 − 13 In most cases, the aerogel coating is prepared by dropcasting and drying a slurry consisting of an aerogel material, solvents, and a binding substance like Nafion. 14 − 17 Because of mixing the slurry, however, the monolithic network is broken into smaller segments.…”

“…Because of their unique physical properties such as high specific surface areas and open-pore structures, aerogels are highly investigated. Recently, those materials gained high interest in applications such as in catalyzed syntheses , as well as in electrocatalytic − and photocatalytic reactions. , Furthermore, a variety of sensing applications were reported. − Owing to the good accessibility of the surface, thin films or coatings from these materials experience an increasing interest. − In most cases, the aerogel coating is prepared by dropcasting and drying a slurry consisting of an aerogel material, solvents, and a binding substance like Nafion. − Because of mixing the slurry, however, the monolithic network is broken into smaller segments. In the resulting coating, these parts are later covered and connected using the binder.…”