Dimethylformamide

Sodium sulfonated styrene (Na-SS ≥ 90%), copper (I) bromide (CuBr, 98%), copper (II) bromide (CuBr2, 99.999%), N,N,N′,N′′,N′′-pentamethyldiethylenetriamine (PMDETA, 99%) and diethyl ether (≥99%) were purchased from Sigma-Aldrich and used as received without any further purification unless explicitly stated. Toluene (99%), tetrahydrofuran (99%), dimethylformamide (DMF, 99.5%), and glacial acetic acid (99.7%) were purchased from Daejung Chemicals and Metals. Copper(I) bromide was purified by washing with glacial acetic acid and diethyl ether, and then filtered, dried, and stored under vacuum for further use. Atom transfer radical polymerization (ATRP) initiator 1-(chlorodimethylsilyl)propyl-2-bromoisobutyrate was synthesized by direct reaction of chlorodimethylsilane (98%) and allyl 2-bromo-2-methylpropionate (98%) in presence of Pt catalyst at room temperature as described in the Section 3.2.

Polyacrylonitrile (PAN, Mw = 150,000) was purchased from Sigma-Aldrich, Co. (St. Louis, MO, USA). Zinc oxide nanoparticles (ZnO NPs, 99% purity) were supplied by Nanjing XFNANO Materials Tech Co. (Beijing, China). The commercial silane coupling agent, 3-methacryloxypropyltrimethoxysilane (MPTMS, 97% purity), and Methylene Blue (MB, 1% wt/vol aqueous solution) were procured from Alfa Aesar Chemical Co. (Seoul, Korea). Dimethylformamide (DMF, 99.8% purity) and potassium chloride (KCl, >99% purity) were obtained from Daejung Chemicals & Metals Co. (Seoul, Korea). Ethyl alcohol (99.9%, anhydrous) was supplied by Samchun Pure Chemical Co., LTD (Seoul, Korea). All reagents were used as received without further purification.

PCL (Mw 80,000), nHA, and Alizarin red staining agent (Aldrich, Gillingham, UK) were purchased from Sigma-Aldrich. WST-1 solution was purchased from Goma Biotech. Chloroform and dimethylformamide (Daejung, Gyeonggi-do, Korea) were purchased from Duksan. Culture media, antibiotics, fetal bovine serum (FBS), and Dulbecco’s phosphate-buffered saline (DPBS) (Welgene, Daegu, Korea) were purchased from Welgene. Dental pulp stem cells were kindly provided by the School of Dentistry, Seoul National University. Polyclonal anti-human osteopontin goat IgG, anti-goat IgG fluorescein isothiocyanate (FITC)-conjugated, tetramethylrhodamine (TRITC)-conjugated phalloidin, and 4′,6-diamidino-2-phenylindole (DAPI) (R&D systems, Minneapolis, MN, USA) were purchased from R&D Systems. Alexa Fluor^® 594 (Thermo Fisher, Frederick, MD, USA) was purchased from Thermo Fisher.
Equine bone-derived nanohydroxyapatite (EBNH) was prepared from previous methods as follows: washed, H₂O₂-pretreated horse bone was sintered at 1300 °C in a furnace to remove organic components and possible contaminants, and then the remaining minerals were processed with a blade grinder and high-power ball mill to produce finer particles and sieved for even size distribution [33 (link)].

The chemicals used for the present research were all analytical grade and used as obtained. Graphite powder (<20 [46 (link)] synthetic), hydrogen peroxide (H₂O₂: 30% w/w in H₂O), potassium permanganate (KMnO₄: ACS reagent grade), ammonia solution (NH₄OH: 25% for analysis EMSURE ISO, Reag. Ph Eur.), sulphuric acid (H₂SO₄: Assay 95%), thermoplastic polyurethane, nickel nitrate hexahydrate (Ni(NO₃)₂.6H₂O: trace metal basis, 99.99%), and sodium nitrate (ACS grade, ≥99.0%) were purchased from SIGMA ALDRICH. Whereas sodium hydroxide (NaOH, 98%), dimethylformamide (Assay 99.9%, SGR grade), ethylene glycol (Assay 99%, FP 116 °C), phosphoric acid (H₃PO₄: 85% HPLC grade), and hydrochloric acid (HCl: assay 36%) were obtained from DAEJUNG. Deionized water was used for the preparation of all solutions.

The monomer4,5-dichlorophthalic anhydride was purchased from Tokyo Chemical Industry (TCI) Co. Ltd. (Tokyo, Japan); 5,5′,6,6′-tetrahydroxy-3,3,3,3′-tetramethyl-1,1′-spirobisindane (97%) was purchased from Alfa Aesar (Seoul, Korea). These were used as obtained. Zirconium chloride (ZrCl₄) and 2-aminoterephthalic acid were obtained from Alfa Aesar (Seoul, Korea). Pebax was purchased from ArkemaInc. Methanol, ethanol, chloroform, dimethyl formamide, and potassium carbonate were purchased from DaeJung Chemicals & Metals Co. Ltd. (Shiheung, Korea) in South Korea. Acetic anhydride, acetic acid, and triethylamine were obtained from Sigma Aldrich. (Yongin, Korea)

4,4′-(hexafluoroisopropylidene) di-phthalic anhydride (6FDA) and dibenzo-18-crown-6 (DB18C6) were purchased from TCI Co. Ltd. (Seoul, Korea). and were used as obtained. Bis(3-aminopropyl) terminated PDMS (M_n = 2500), triethylamine, hydrazine monohydrate, acetic anhydride, nitric acid, and anhydrous acetic acid were obtained from Sigma-Aldrich Korea (Yongin, Korea) and were used without purification. Pd/C catalyst (palladium, 10% on carbon, Type 487, dry) was purchased from Alfa-Aesar (Seoul, Korea). Ethanol, isopropanol, tetrahydrofuran, dimethylacetamide, dimethylsulfoxide, and dimethylformamide were purchased from DaeJung Chemicals & Metals Co. Ltd. (Shiheung, Korea). Trans-diamino-DB18C6 (3) was synthesized following previous reports [21 (link),22 (link)], and the procedures are described in the Supporting Information. All other chemicals were obtained from commercial sources.