Calcium chloride dihydrate

Medium-molecular-weight CS 80/50 (degree of deacetylation: 77.6–82.5%, viscosity of 1% solution in 1% acetic acid: 31–70 mPa·s, molecular weight: 80–200 kDa) was obtained from Heppe Medical CS GmbH (Haale, Germany). Low-methoxy amidated PC with low- (a type CF 010, degree of esterification 34%, degree of amidation 17%, pH 4.2 for 2.5% solution in distilled water at 20 °C) and high-calcium reactivity (a type CF 020, degree of esterification 31%, degree of amidation 19%, pH 4.1 for 2.5% solution in distilled water at 20 °C) were kindly gifted by Herbstreith & Fox and GmbH & Co. KG (Neuenbürg, Germany). Potassium dihydrogen phosphate, sodium chloride, calcium chloride dihydrate, and 85% lactic acid were purchased from Chempur (Piekary Śląskie, Poland). Glycerol was obtained from Fagron (Kraków, Poland).
SSS composed of Potassium dihydrogen phosphate (1.63 mg/mL), sodium chloride (2.32 mg/mL), and calcium chloride dihydrate (0.22 mg/mL) with pH 6.2 adjusted by disodium hydrogen phosphate addition (according to Nair et al. with modification [25 (link)]) was used for the research analyses.

Common sage (Salvia officinalis) dried leaves were purchased from Lord Nelson (Tarnowo Podgórne, Poland). All reagents used for HA synthesis, i.e., the sodium phosphate dibasic (Na₂HPO₄), calcium acetate monohydrate (Ca(CH₃CO₂)₂·H₂O), ammonium phosphate monobasic and ammonia water (NH₄OH, 25%) as well as sodium alginate (SA), polyvinylpyrrolidone (PVP), poly(ethylene glycol) diacrylate average Mn 700 (PEGDA), gelatin (GE), 2-hydroxy-2-methylpropiophenone 97%, 2,2-Diphenyl-1-picrylhydrazyl (DPPH), triethanolamine ≥ 99.0% (TEA), gallic acid and edetate disodium were obtained from Sigma-Aldrich (Darmstadt, Germany). Urea was purchased from Stanlab (Lublin, Poland) and phosphate buffered saline (PBS) from Oxoid (Basingstoke, UK). The bismuth(III) nitrate pentahydrate (Bi(NO₃)₃), sodium carbonate (Na₂CO₃), potassium chloride (KOH), sodium chloride (NaCl), nitric acid (HNO₃), hydrochloric acid (HCl), ethanol 96%, calcium chloride dihydrate (CaCl₂·2H₂O) and sodium sulfide nonahydrate (Na₂S · 9H₂O) were obtained from Chempur (Piekary Śląskie, Poland).

In the present work, the following materials were used: polyvinyl alcohol (PVA, Mowiol^® 56–98, Mw ~195.000 Da; degree of hydrolysis 98.4 ± 0.4 mol%) obtained from Merck KGaA (Darmstadt, Germany); propylene glycol (PG) (Chempur, Piekary Śląskie, Poland); Labrasol^® (L) kindly donated by Gattefossé (Saint-Priest, France); gamma-irradiated fetal bovine serum (FBS) (Thermo Fisher, Waltham, MA, USA); sodium chloride (Avantor Performance Materials, Gliwice, Poland); calcium chloride dihydrate (Chempur, Piekary Śląskie, Poland).