Naco3

All chemicals were of analytical grade and used without further purification. Solutions were prepared with doubly distilled water (18.2 MΩ cm). Reagents used were Nafion® 117 at 5% w/v solution; H₂SO₄; NaCO₃ and NaHCO₃ (Sigma–Aldrich, Merck KGaA, Darmstadt, Germany); CuSO₄ (Carlo Erba Regents, Milan, Italy); Na₂SO₄ (Fluka, Buchs, Switzerland); NaNO₃ (Alfa Aesar, Karlsruhe, Germany).

All chemicals and solvents used were of analytical grade. Methanol, gallic acid, 10% (v/v) Folin-Ciocalteu reagent, DPPH (2,2-diphenyl-1-picryl-hydrazyl), Trolox (6-hydroxy-2-5-7-8- tetramethylchroman-2-carboxylic acid), sodium acetate trihydrate (C₂H₃NaO₂·3H₂O), glacial acitic acid (C₂H₄O₂), TPTZ (2,4,6-tri(2- pyridyl)–s-traizine), ferric chloride (FeCl₃.6H₂O), HCl, ABTS (2,2-azino-bis(3–ethylbenzthiazoline-6)-sulfonic acid), KH₂PO₄ (potassium phosphate dibasic), NaNO₂, NaCO₃, H₂SO₄, D-glucose, and NaOH, obtained from Sigma Aldrich, St. Louis, MO, USA through Analytical Instrument Pvt, Colombo, Sri Lanka.

HPLC-grade acetonitrile and methanol were purchased from Labscan (Dublin, Ireland). Acetic acidof analytical grade (assay >99.5%) was purchased from Fluka (Buchs, Switzerland). Water was purified by using a Milli-Q System (Millipore, Bedford, MA, USA). Other reagents unmarked were of analytical grade. methanol (MeOH) was purchased from Carlo Erba (Rodano, MI, Italy), H₂O₂ was bought from Farmac-Zabban S.p.a. (Calderara di Reno, BO, Italy), NaCO₃, gelatin and Hoechst 33342 were obtained from Sigma-Aldrich (Milan, Italy), poly(vinylidenefluoride-co-trifluoroethylene) [P(VDF-TrFE)] powder (70:30 % mol) was purchased from Piezotech Arkema (Pierre-Benite, France), Methyl ethyl ketone (MEK) was bought from Merck (Darmstadt, Germany). Medium 199 (M199), fetal bovine serum (FBS), penicillin-streptomycin solution, L-glutamine, HEPES buffer were supplied by Hospira S.r.l. (Naples, Italy).
4-[3-(4-iodophenyl)-2-(4nitrophenyl)-2H-5-tetrazolium]-1,3-benzenedisulfonate (WST-1 assay), was purchased from Roche Applied Science (Mannheim, Germany), 5-(and-6)-chloromethyl-2’,7’-dichloro-di-hydro-fluorescein diacetate, acetyl ester (CM-H₂DCFDA) was supplied by Invitrogen. EGM-2 medium bullet kit was bought from Lonza (Verviers, Belgium), alamarBlue^® was obtained from Thermo Fisher Scientific (Waltham, MA, USA).

Madder roots (Rubia tinctorum L.) and alum (KAl(SO₄)₂) were purchased from “Chroma” srl. Genuine indigo in pieces (Indigofera Tinctoria), rabbit skin glue, and CaSO₄ were purchased from Kremer Pigmente (Germany). Bricks were purchased from “Mattone Romano” srl (Italy). KC₄H₅O₆ was purchased from a grocery shop. Turmeric was purchased from Chroma. Agar in powder (ash 2.0–2.4%), solvents, and salts, such as ammonia (30–33%), NaCO₃ (≥99.0%), Na₂S₂O₄ (≥82.5%), K₂CO₃ (with impurities ≤55.0 ppm), NaOH (≥95%), hydroxylamine hydrochloride (99.9%), NaCl (with impurities ≤0.005% as insoluble matter), Na₂EDTA (with impurities ≤0.005% as insoluble matter), silver nitrate (≥99.0%), HCl (37%), HCOOH (≥95%), 2-propanol, and 1-pentanol, were purchased from Sigma-Aldrich. Nanorestore Gel^® High Water Retention was purchased from CSGI (Center for Colloid and Surface Science).