Aqueous ammonium hydroxide nh4oh

All reagents were used as received from the suppliers without further purification. Tetraethylorthosilicate (TEOS), 3-aminopropyltriethoxysilane (APTS), polyvinylpyrrolidone (PVP) (Mw 40,000), silver nitrate (AgNO₃), L-ascorbic acid, Tween 20, tetrakis(hydroxymethyl)phosphonium chloride (THPC), gold (III) chloride trihydrate (HAuCl₄), and histamine dihydrochloride were purchased from Sigma-Aldrich (St. Louis, MO, USA). Ethyl alcohol (EtOH) and aqueous ammonium hydroxide (NH₄OH) were purchased from Daejung (Siheung, South Korea). HCl and NaOH were purchased from Samchun (Pyeongtaek, South Korea). Phosphate-buffered saline (PBS; 20×) was purchased from Dyne Bio (Seongnam, South Korea). Ultrapure water (resistivity 18.2 MΩ×cm) was produced using a Millipore water purification system (EXL water purification, Vivagen Co., Ltd., Seongnam, South Korea).

Tetraethylorthosilicate (TEOS), 3-mercaptopropyl trimethoxysilane (MPTS), ethylene glycol (EG), silver nitrate (AgNO₃), octylamine (OA), ethyl alcohol (EtOH, 99.5% and 95%), 1-(p-toluenesulfonyl) imidazole, sodium hydroxide (NaOH), ammonium chloride (NH₄Cl), acetone, propane-1, 3-diamine, β-cyclodextin, and polyvinylpyrrolidone (PVP, MW 40,000) were purchased from Sigma-Aldrich (St. Louis, MO, USA) and used without further purification. Aqueous ammonium hydroxide (NH₄OH, 27%) was purchased from Daejung (Siheung, Korea). Water was purified using a Direct-Q Millipore water purification system (SAM WOO S&T Co., Ltd., Seoul, Korea). Tosyl β-CD was obtained from microbial Carbohydrate Resource Bank (Seoul, Korea).

Tetraethylorthosilicate (TEOS), 3-aminopropyltriethoxysilane (APTS), tetrakis(hydroxymethyl)phosphonium chloride (THPC), polyvinylpyrrolidone (PVP), phosphate buffer saline (PBS), phosphate buffer saline containing 0.1% Tween 20 (PBST), ascorbic acid (AA), chloroauric acid (HAuCl₄), hydrofluoric acid (HF), 4-aminothiophenol (4-ATP), 4-mercaptobenzoic acid (4-MBA), 1-undecanethiol (R-CH₃), 11-mercaptopundecanoic acid (R-COOH), 11-mercapto-1-undecanol (R-OH), hydrogen peroxide (H₂O₂), and 5,5′-Tetramethylbenzidine (TMB) were purchased from Sigma-Aldrich (St. Louis, MO, USA). Ethanol (EtOH), sulfuric acid (H₂SO₄), buffer pH 4.0, and aqueous ammonium hydroxide (NH₄OH, 27%) were purchased from Daejung (Sihung, Gyeonggi-do, South Korea); and ultrapure water (18.2 MΩ cm) was produced by a Millipore water purification system (EXL water purification; Vivagen Co., Seongnam, Gyeonggi-do, Korea).