Calcium chloride dehydrate

Alginic acid sodium salt and porcine gelatin (300g Bloom) were obtained from Sigma-Aldrich (St. Louis, MO, USA). Calcium chloride dehydrate was obtained from Fisher (Fair Lawn, NJ, USA). Deionized MilliQ water (18 MΩ) was obtained from an in-house purification system. Adipose-derived stromal cells (ADSCs) and MCF-7 mammary adenocarcinoma cells (ER⁺, PR⁺) were obtained from the American Type Culture Collection (ATCC, Manassas, VA, USA).

Sodium phosphate (NaH₂PO₄, ACS), Magnesium chloride hexahydrate (MgCl₂^.6H₂O), sodium chloride (NaCl, ACS), potassium chloride (KCl), disodium hydrogen phosphate (Na₂HPO₄), sodium Sulfate (Na₂SO₄), calcium chloride dehydrate (CaCl₂.2H₂O), sodium acetate, sodium hydrogen carbonate (NaHCO₃), and sodium citrate dehydrate (C₆H₅O₇Na₃·2H₂O) were from Fisher Scientific.
Standard solutions of L-ascorbic acid sodium salt (AA), (Sigma Aldrich) were prepared at 10 mM concentration in ultrapure water (Milli-Q® IQ 7000 water purification system). Solutions of DTT and DTNB (Sigma Aldrich) were prepared in phosphate buffer (at 10 mM) and maintained in ice and in the dark during the experiment.
Aqueous solutions of the reagents are unstable at room temperature and sensible to light, thus they were preserved in amber glass vials in the dark at − 20 °C.
Copper (II) sulfate (98 %), iron (II) chloride (ACS), 1,2-naphthoquinone (1,2-NPQ, 97 %), and 9,10-phenanthrenequinone (9,10-PNQ, 99%) were from Sigma-Aldrich and Acros Organics. Individual standard stock solutions were prepared for each analyte by weighting pure standards with a concentration of 10⁻² M using MilliQ water for metal ions and acetonitrile for quinones as solvent.
Methanol was HPLC grade solvent purchased from Sigma-Aldrich.

Sodium alginate (Alg) and calcium chloride dehydrate (CaCl₂ ≥ 99%) were purchased from Fisher Scientific, Waltham, MA, USA. Cefotaxime sodium powder for injections (CTX, batch number 200526) was purchased from UP Pharma, Assuit, Egypt.

Digitoxigenin and olive oil (highly refined, low acidity) were purchased from Sigma-Aldrich (St. Louis, MO, USA). Alginic acid sodium salt (low viscosity) was from MP Biomedicals (Solon, OH, USA). Tween 85 (Acros Organics, Morris, NJ, USA) and Span 85 (Sigma-Aldrich, St. Louis, MO, USA) were used in the preparation of Digitoxigenin formulations. Other reagents used were isooctane (Acros Organics, Morris, NJ, USA) and calcium chloride dehydrate (Fisher Scientific, Springfield, NJ, USA). Phosphate buffered saline (PBS) of pH 7.4 was prepared by dissolving PBS tablets (MP Biomedicals, Solon, OH, USA) in deionized water, and sodium azide (Acros Organics, Morris, NJ, USA) was added at a concentration of 0.02% (w/v) as a bacteriostat. High performance liquid chromatography (HPLC) grade methanol, water, and formic acid were purchased from Fisher Scientific (Pittsburgh, PA, USA).