Iron 2 sulfate tetrahydrate

Methanol (CH₃OH, 99.9%), silver nitrate (AgNO₃), nutrient agar, ferric chloride hexahydrate (FeCl₃, 6H₂O), iron (II) sulfate tetrahydrate (FeSO₄.4H₂O), dichloromethane, polyethylene glycol 300, ascorbic acid and Mueller-Hinton agar (MHA) were purchased from Merck (Germany). 2,2-diphenyl-1-picrylhydrazyl (DPPH), 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and 2,4,6-Tripyridyl-s-Triazine (TPTZ) were purchased from Sigma (Germany) and poly lactic acid (PLA) from Zhejiang Hisun Biomaterials (China). The RAW264 macrophage cell line was purchased from National Cell Bank, Pasteur Institute of Iran, Iran and Dulbecco’s Modified Eagle’s Medium (DMEM), Fetal Bovine Serum (FBS), 1% Penicillin-Streptomycin from Gibco (Paisley, UK). All aqueous solutions were prepared using double distilled water. All reagents used were of analytical grade. Clinical strains of Pseudomonas aeruginosa^{38 (link)} and Staphylococcus aureus^{39 (link)} bacteria were isolated from hospitalized patients by our group, which have been characterized as antibiotic-resistant strains.

For the preparation of graphene oxide (GO) according to the modified Hummer’s method, the chemicals including, sulfuric acid (> 98%), ortho- Phosphoric acid (85%), potassium permanganate (KMnO₄), hydrogen peroxide (30%), and hydrochloric acid (37%), were purchased from Merck. Pristine graphite powder was supplied from Fluka Company. The precursors for the synthesis of the functionalized MGO were iron (II) sulfate tetrahydrate (FeSO₄·4H₂O, 99.7%), iron (III) chloride hexahydrate (FeCl₃·6H₂O, 99.0%), ammonia (NH₄OH, 25 wt%), absolute ethanol, 3-aminopropyl triethoxysilane (AP), and glutaraldehyde (GA) and were purchased from Merck. Rhizopus oryzae lipase (light brown powder, ≥ 30,000 U/g) was purchased from Sigma–Aldrich. Reagents for the nano-biocatalysts assay, p-nitrophenyl palmitate (p-NPP), isopropyl alcohol (99.7%), bovine serum albumin (BSA), Coomassie Brilliant Blue G-250, Triton X-100, and Arabic gum were purchased from Merck. BG-11 medium (Blue-Green medium) components, for the cultivation and maintenance of the microalgae Chlorella vulgaris CCAP were obtained from either Merck. All organic solvents and other chemicals purchased from Merck and were of analytical grade.