Carbon dioxide

The following reagent grade or purer chemicals were used: molecular biology grade ethanol (200 proof) and hydrochloric acid from Fisher Scientific; equine cytochrome c and quercetin from Sigma‐Aldrich; tris(hydroxymethyl)aminomethane base from Dot Scientific. Nitrogen (99.998%) and carbon dioxide (99.5%) were from Praxair. All chemicals were used without further purification. A total of 0.15 mm thick LDPE was from McMaster‐Carr.

The following reagent grade or greater chemicals were utilized: HyClone™ McCoy's 5A media (1.5mM L‐Glutamine, 2.2g/L sodium bicarbonate), Dulbecco's Modified Eagle's Medium‐high glucose (4.5g/L Glucose, L‐Glutamine, and Sodium Pyruvate) from VWR Life Sciences; Fetal Bovine Serum from Omega Scientific, Gibco™ Trypsin‐EDTA (0.25%), phenol red, Hyclone™ Phosphate‐Buffered Saline ((1X) 0.0067M PO4) without calcium, magnesium, phenol red, HyClone™ Trypan Blue Solution from Thermo Fisher Scientific, Optima LC/MS grade methanol and water, Optima LC/MS grade formic acid, molecular biology grade ethanol (200 proof) from Fisher Scientific; alamar Blue® from VWR, Gallic Acid monohydrate from Acros Organics; Folin–Ciocalteu reagent from Merck; Sodium Carbonate–Monohydrate from J. T. Baker Chemical; and ultrapure water produced on‐site. Nitrogen (99.998% purity) and carbon dioxide (99.5% purity) were from Praxair. Chemicals were used without further purification.

The commercial oils screened were olive oil (Gallo, Alges, Portugal), sunflower oil (Fula, Alges, Portugal) and corn oil (Fula, Alges, Portugal). Surfactants used for emulsification were PEG 300 (Clariant, Muttenz, Switzerland), Span^® 80, Tween^® 80, Triton™ X-100 Detergent and SDS (≥99% (GC), dust-free pellets), which were procured from Sigma Aldrich, Portugal (made in Lyon, France). Potassium carbonate (>99.5% pure, Scharlab S.L., Sentmenat, Spain) was used to prepare a solution to adjust the pH to 11. Carbonic anhydrase from bovine erythrocytes (≥95% (SDS-PAGE), specific activity ≥3500 W-A units/mg protein, lyophilised powder) was acquired from Sigma Aldrich, Portugal (made in St. Louis, MI, USA). The gases used, carbon dioxide (98% purity) and methane (99% purity) were purchased from Praxair (Huelva, Spain). The commercial membranes used in this study are detailed in Table 1.

Alginic acid sodium salt was supplied by BASF, Germany. Calcium chloride (CaCl₂) was purchased from Th. Geyer GmbH & Co. KG, Germany. Carbon dioxide (purity ≥ 99.5%) was supplied by Praxair (Germany), ethanol 99.8% was obtained from Carl Roth (Germany). All chemicals were used as received. Commercial diagnostic kits were used to measure ALP, and creatinine kits were purchased from Biostsystems S.A, Spain. The MO BIO’S PowerMax Soil DNA Isolation Kit were purchased from MO BIO Laboratories, USA. Deionized water was used throughout the study.

High viscosity sodium alginate from brown algae (HMW, 180 kDa, 1% viscosity: 65 mPa·s; M/G ratio 70/30) was purchased from Carlo Erba (Milan, Italy) and medium viscosity sodium alginate from brown algae (MMW, 120 kDa, 1% viscosity: 40 mPa·s; M/G ratio 70/30) from Dompè Pharma (L’Aquila, Italy). Calcium chloride (CaCl₂, 93% purity) was obtained from Sigma-Aldrich (Milan, Italy) and absolute ethanol (≥99.8% purity) from VWR (Llinars del Vallés, Spain). Carbon dioxide (99.8% purity) from Praxair (Madrid, Spain) was used for the supercritical drying of the gels. All other reagents were purchased from Sigma-Aldrich (Milan, Italy) and employed as received.

Medium molecular weight (MMW) chitosan polymer with 75%–85% deacetylation degree (viscosity 200 ÷ 800 cps, 1% concentration solution in 1% acetic acid at 25 °C), phosphate buffer saline (PBS), and poly(ethylene glycol) (PEG; molecular weight = 400 g/mol) were purchased from Sigma-Aldrich (Saint Louis, MO, USA). The PLA pellets were purchased from ORBI-TECH (Leichlingen, Germany). Calcium chloride, lactic acid, sodium hydroxide, sodium chloride, and chloroform were purchased from “Avantor Performance Materials Poland” (Gliwice, Poland). Carbon dioxide was bought from “Linde” (Gdansk, Poland).
The bacterial strains: Escherichia coli K-12 PCM 2560 (NCTC 10538) and Staphylococcus aureus PCM 2054 (ATCC 25923) were provided from Polish Collection of Microorganisms, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy of the Polish Academy of Sciences, Wrocław, Poland. The TSB, TSA, and peptone were purchased from “Biocorp” (Warsaw, Poland). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), medium, antibiotics, and supplements necessary for cell culture were obtained from Sigma-Aldrich (St. Louis, MO, USA). MilliQ water was used for the preparation of all aqueous solutions. All other reagents were of analytical grade or higher.