Mgcl2 6h2o

Phosphate buffered saline (PBS), Trizma base (Tris), HCl, ethanolamine, ammonium sulphate, and Tween-20 were purchased from Sigma-Aldrich (St. Louis, MO, USA). Copoly(DMA-NAS-MAPS) (MCP-2) was purchased from Lucidant Polymers Inc. (Sunnivale, CA, USA). SP-IRIS printed microarrays were provided by nanoView Diagnostics Inc.
Monoclonal antibodies against the human tetraspanins CD63, CD81, CD9, and CD171 were purchased from Nexgenarrays LLC (Boston, MA). Pure whole molecules IgG from Goat (R&D Biosystems) or Rabbit (Jackson Immunoresearch, West Grove, PA, USA) were used as negative controls.
Artificial cerebrospinal fluid was composed of NaCl (120 mM), NaHCO₃ (25 mM), KCl (2.5 mM), NaH₂PO₄ (1 mM), CaCl₂ (2.5), MgCl₂⋅ 6 H₂O (1 mM), Glucose (20 mM) and Human Serum Albumin (0.4 mg/mL), all purchased from Sigma-Aldrich (St. Louis, MO, USA).

Blank Pallflex TX40 FDMS filters were supplied by Air Monitors (Gloucestershire, UK). These are made of borosilicate microfibres reinforced with woven glass cloth and bonded with polytetrafluoroethylene (5 mg cm⁻², 47 mm diameter). The pH of solutions was measured by using a Mettler-Teledo (SevenGo™) pH meter. Suspensions were shaken in an end-over-end rotator inside an incubator (Stuart® SI500 shaking incubator from Barloworld Scientific Ltd., Staffordshire, UK). All glassware and plastic ware were soaked overnight in 10% HNO₃ then rinsed three times with deionised water before use. All chemicals were of analytical grade. Bovine serum albumin, NaH₂PO₄, KCl, pancreatin (porcine), urea, CaCl₂·2H₂O and pepsin (porcine) were purchased form Merck (Poole, UK). Glucose, NaCl, Na₂SO₄, NH₄Cl, NaHCO₃ and NaOH were supplied by VWR International (Lutterworth, UK). Lysozyme, glutathione, MgCl₂·6H₂O, glucuronic acid, glucosamine hydrochloride, mucin (porcine), DPPC, hydrochloric acid (HCl) (36.5–38%) and nitric acid (HNO₃) (≥69% Trace SELECT® for trace analysis) were obtained from Sigma Aldrich (Gillingham, Dorset, UK). Glycine was purchased from Fisher Scientific (Loughborough, UK). Multi-element standard stock solution (10 mg L⁻¹ of As, Cd, Cr, Cu, Mn, Ni, Pb and Zn) and Fe standard stock solution (1003 mg L⁻¹) were obtained from Qmx Laboratories (Essex, UK).

The reagents applied in the present study: MgCl₂×6H₂O, EGTA (ethylene glycol-bis(β-aminoethyl ether)-N,N,N′,N′-tetraacetic acid), taurine, KH₂PO₄, lactobionic acid, sucrose, HEPES (4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid), BSA (bovine serum albumin), digitonin, glutamate, malate, succinate, ADP (adenosine diphosphate), oligomycin, rotenone, antimycin A, FCCP (Carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone), betulinic acid (BA), and DMSO (dimethyl sulfoxide—the vehicle used for BA solubilization) were purchased from Sigma Aldrich, Merck KGaA(Darmstadt, Germany). All reagents used were of analytical purity. Cell culture media—Dulbecco’s modified Eagle Medium (DMEM) and specific supplements were acquired from Sigma Aldrich, Merck KGaA (Darmstadt, Germany), ATCC (American Type Cell Collection, Lomianki, Poland) and Thermo Fisher Scientific, Inc. (Waltham, MA, USA). XFe24 well plates, XF sensor cartridges, and XF Assay media were provided by Agilent Technologies, Inc. (Santa Clara, CA, USA).

Dulbecco’s modified Eagle’s medium (DMEM) with high glucose (4500 mg/L), 1% penicillin-streptomycin solution (10,000 units of penicillin and 10 mg of streptomycin in 1 mL 0.9% NaCl), EGTA, ethanol, HEPES (1 M), isopropanol, KH₂PO₄, mannitol, MgCl₂·6H₂O, MTT, non-essential amino acids (NEAA) (100×), l-glutamic acid, l-malic acid, potassium lactobionate, sodium pyruvate, sodium pyruvate solution (100 mM), succinic acid, and taurine were purchased from Sigma (St. Louis, MO, USA). Fetal bovine serum, 0.05% trypsin/0.53 mM EDTA solution, 1× PBS (pH 7.4), l-glutamine (200 mM) were supplied by Thermo Fisher Scientific (Waltham, MA, USA).