Multiuse Al-MOF Chemosensors for Visual Detection and Removal of Mercury Ions in Water and Skin-Whitening Cosmetics

Abstract

Water and cosmetics containing mercury can cause damage to the skin and body. There is a great need for in situ monitoring and removal of mercury ion concentrations with a highly selective, sensitive, accurate, rapid, and simple protocol in water and skin-whitening cosmetic products. In situ recognition is an easy and inexpensive approach for recognition and uptake of Hg 2+ ions in skin-lightening cosmetics and water. Our system is based on the fabrication of a sticklike structure of the newly developed metal−organic framework (MOF) via a solvothermal protocol. The rodlike structure of the Al-MOF has a tremendously high surface area which is a powering point that supported it as a microporous substrate for loading a Hg 2+ ion chromophore (bis(4-(dimethylamino)phenyl)methanethione). The thioketone derivative chromophore based on an Al-MOF microporous carrier allows visual monitoring of toxic mercury in a few seconds. The proposed chemosensors have a color change from yellow to a green color that is extremely noticeable by the naked eye. Our designated chemosensors sensitivity (0.8 ppb) toward mercury ions was found to be lower than the WHO permissible drinking water limits which made it a good choice for in situ pretests of drinking water. Moreover, superior adsorption characteristics of the fabricated thioketone Al-MOF (TAM) nanorods as adsorbent were achieved. A high adsorption capacity was observed (1110 mg/g) in solution for capturing of mercury ions. Our developed protocol is built on the use of a small amount of prepared optical chemosensors, about 20 mg, for all measurements and the potential for multiple uses after a simple regeneration process. Our results revealed that the designed TAM nanorods would be a promising means of visualizing mercury ions in water and cosmetics products.

Development of a Sensitive and Selective Optical Sensor for Measuring Ultra‐Trace Amounts of Fe(II) and Fe(III) Ions in Water

“…The mesoporous silica attracted attention because of its specific surface functionality, porous wall structure, biocompatibility, and hydrophilic design [13–22] . MSNSs (mesoporous silica nanospheres) were created and used as a scaffold for accommodating new ion chromophores in this study (Phimhb).…”

“…In addition, the pore volume of the MSNss was 0.699 cm 3 /g, while the pore volume of the Phimhb sensor was 0.559 cm 3 /g. The Phimhb sensor still has a high surface area because incorporating the chromophore Phimhb molecules into the mesoporous silica surface is physical adsorption (van der Waals adsorption) [13–22] . The fact that the Phimhb chromophore is conserved both outside and inside the nanosphere may explain why Phimhb sensors have smaller pore widths and surface areas.…”

“…Many papers showed that the use of nanomaterials as a scaffold for immobilization of the reagents enhances their selectivity and sensitivity [13–22] . From this point of view, we tried to far away from the routine work and make a chemosensor.…”

“…Optical technologies enable in situ identification with the naked eye by modifying the color without the use of expensive instruments. As a result, numerous investigations on metal ion colorimetric sensing systems have been published [13–22] …”

Matrix effects on the performance and mechanism of Hg removal from groundwater by MoS2 nanosheets

“…Mercury (Hg) is recognized as one of the most remarkably toxic contaminants and widely present in environmental matrices such as soil and groundwater. 1,2 Generally, Hg in the environment is generated from industrial activities, agriculture, and natural sources. [3][4][5][6] In groundwater, Hg mainly exists as inorganic species (an average of 84% of soluble Hg) 7 and Hg pollution occurs via deep-well disposal of liquid wastes, the leachate from a number of contaminated sources such as landlls, sewage, mine tailings, and industrial waste lagoons.…”