Potassium chromate k2cro4

The cytotoxicity of CA was conducted using Brine Shrimp Lethality Assay (BSLA) by the method of Meyer et al. [11 (link)] with several modifications. Brine shrimp eggs (Artemia Salina Leach) were permitted to hatch as larvae (nauplii) in artificial sea water under light and good aeration. After 48 h, the larvae were transferred to plate-24 well plates and added with 1.0 ml sea water. The solution of extract was added until the concentration extract in wells of 1000, 500, 250, 125, 50, and 10 µg/ml. Negative control was made by using 2 ml artificial seawater without adding the extract. Potassium chromate K₂CrO₄ (Sigma Aldrich, St. Louis, MO, USA) was used as positive control with concentrations of 5.0, 10.0, 15.0, 20.0, and 25.0 µg/ml in artificial sea water. The numbers of surviving larvae in each well were counted after 24 h. The concentration that killed 50% of the nauplii (LC₅₀) and 95% confidence interval were calculated by Graphad using Probit analysis. The plant samples were weight three times and the procedure was performed in triplicate for each plant sample.

The ELMs were formulated with four different types of emulsifiers: Tween 80 (Polyoxyethylene sorbitan monooleate) from Sigma-Aldrich (Darmstadt, Germany) with an HLB of 15.0, Span 80 (Sorbitan monooleate) from VWR International Prolabo (Radnor, PA, USA) with an HLB of 4.3, PGPR (Polyglycerol polyricinoleate) from Brenntag AG (Essen, Germany) with an HLB of 3.0, and Tween 20 (Polyoxyethylene sorbitan monolaurate) from Sigma-Aldrich (St. Louis, MO, USA) with an HLB of 16.7. The mobile carrier or extractant used was TOPO (tri-n-Octylphosphine oxide), supplied by Avocado Research Chemicals Ltd. (Morecambe, UK). Sunflower oil was used as a solvent or diluent (density = 0.689 g/cm³, viscosity = 0.044 Pa·s).
Analytical grade hydrochloric acid (HCl), acetone (C₃H₆O), sulphuric acid (H₂SO₄), sodium carbonate (Na₂CO₃·10H₂O), and potassium chromate (K₂CrO₄) were purchased from Sigma-Aldrich (St. Louis, MO, USA).

HeLa and HCT116 cells were purchased from the American Type Culture Collection (Manassas, Va.). The HCT116 + Ch3 with reconstituted MLH1 protein expression and functional mismatch repair were described previously [12 ]. These cell lines were grown at 37°C in Dulbecco's Modified Eagle Medium (DMEM) supplemented with 10% fetal bovine serum in a humidified 5% CO₂ atmosphere. Potassium Chromate (K₂CrO₄) was obtained from Sigma (St. Louis, MO) and was dissolved in sterile PBS. K₃CrO₈ (Cr[V]) and Cr(diethylenetriamine)(O₂)₂.H₂O (Cr[IV]) were obtained from N.S. Dalal at Florida State University. Cr[V] was dissolved in sterile KOH and Cr[IV] was dissolved in sterile PBS prior to use.
Head and neck squamous cell carcinoma FaDu (ATCC HTB-43) cells were also used for the study, which the cells were originated from pharynx epithelia. FaDu cells were maintained in EMEM. Norma human lung fibroblast 19Lu cells were purchased from ATCC (CC1-210), and mouse lung fibroblast WT13 cells were kindly donated by Dr. Ding, Division of Pulmonary, Allergy & Critical Car Medicine at UAB. 19Lu cells were cultured in MEM and WT13 cells were in DMEM. These cells were grown at 37°C with 5% CO2 and the medium was supplemented with 10% FBS (Sigma-Aldrich) and 100 units/ml penicillin, 100μg/ml streptomycin.

2-acrylamido-2-methyl-1-propanesulfonic acid, AMPSH (99%, Aldrich, Chile), (3-acrylamidopropyl)trimethylammonium chloride, APTACl solution (75% in water, Aldrich, Chile), dimethylsulfoxide (DMSO) (Merck, Chile), acetone (Merck, Chile), GMA (97%, Aldrich, Chile), (NH₄)₂S₂O₈ (98%, Aldrich, Chile), 4-(dimethylamino)pyridine (DMAP) (98%, Aldrich, Chile), ethanol (Merck, Chile), sodium hydroxide NaOH (Merck, Chile), nitric acid HNO₃ (65%, Merck, Chile), sodium bisulfite NaHSO₃ (98%, Aldrich, Chile), copper(II) nitrate trihydrate Cu(NO₃)₂⋅3H₂O (98,9%, Merck, Chile), potassium chromate K₂CrO₄ (99, 9%, Merck, Chile), and sodium arsenate dibasic heptahydrate Na₂HAsO₄⋅7H₂O (98%, Merck, Chile).