Mercury 2 acetate

All the
experiments were performed in aqueous solution. Citric acid anhydrous
99.5% (Loba Chemie Pvt., Ltd., India) and urea 99.5% (Loba Chemie
Pvt., Ltd., India) were used for CD synthesis. The standard solution
of 1000 mg/L Hg²⁺ was prepared by dissolving mercury(II)
acetate (Sigma-Aldrich, USA) in deionized water and used as a stock
solution. The working standard solution of 0.3–600 mg L^–1 Hg²⁺ was prepared by diluting the stock
solution. Acetate buffer (0.10 M) at pH 6 and 7 was prepared from
acetic acid (Carlo Erba, Italy) and sodium acetate (Sigma-Aldrich,
USA). Phosphate buffer (0.1 M) at pH 6 was prepared from sodium phosphate
(Sigma-Aldrich, USA). All of the solutions were prepared in deionized
water.
In this work, we aimed to quantitatively analyze Hg²⁺ in skincare products. Different products for skin conditions,
particularly whitening cream, were purchased from the online market,
local cosmetic shops, and supermarkets in Nakhon Pathom, Thailand.
For analysis, the exact weight of 0.10 g of the sample was dissolved
in 0.50 mL of 5% (v/v) HNO₃ (Carlo Erba, Italy), and the
volume was made to 25 mL in a volumetric flask by 0.1 M acetated buffer
at pH 7.0, which was then injected to the SIA system. All samples
were analyzed using the proposed flow system and the ICP-MS reference
method.

Mercury(ii) acetate was purchased from Sigma-Aldrich Co. Ltd. Potassium tetrachoroaurate(iii) was purchased from ChemPur. Phenylacetylene was purchased from Acros Organics. Tetrahydrofuran and dichloromethane for the reactions were purified using an Innovative Technology, Inc. PureSolv MD 5 Solvent Purification System before use. All of the other solvents and commercially available reagents were of analytical grade and were used as received. Tetra(n-butyl)-ammonium hexafluorophosphate (Aldrich) was recrystallized three times from absolute ethanol before use. All of the reactions were performed under inert and anhydrous conditions using standard Schlenk techniques unless otherwise specified.