Mes free acid monohydrate

CM-dextran sodium salt (CMD-Na), phosphate-buffered saline (PBS), 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC), N-hydroxysulfosuccinimide (NHS), ethanolamine, potassium chloride (KCl), potassium ferricyanide (Fe(CN)₆³⁻), hydrogen peroxide (H₂O₂), diethyl pyrocarbonate (DEPC), and 3,3′,5,5′-tetramethylbenzidine (TMB) were purchased from Sigma-Aldrich (Sigma-Aldrich St. Louis, MO, USA). Anti-fluorescein horseradish peroxidase (HRP) is a 40,000 dalton protein supplied by Abcam (Cambridge, UK). MES free acid monohydrate, hydroxymethyl-aminomethane (Tris), and ethylenediaminetetraacetic acid (EDTA) were purchased from Amresco (Amresco Inc., Solon, OH, USA). Core streptavidin was from BiVision (Bioptics, Tucson, AZ, USA). Sodium chloride (NaCl) was from Promega Corporation (Madison, WI, USA). The biotinylated ssDNA probe (bioreceptor probe) (5′-CAGACAGTGTTA-3′-(CH2)₆-biotin), fluorescein (FITC) ssDNA probe (detector probe) (FITC-(CH2)₆-5′-CCATCTTTAC-3′), and artificial mimic targeting sequence (5′-UAA CAC UGU CUG GUA AAG AUG G-3′) were designed by us and made by Genomics (Taipei, Taiwan). Screen-printed carbon electrodes (SPCEs) were purchased from Zensor R&D (Taichung, Taiwan).

The experimental material consisted of a screen-printed carbon electrode (SPCE) as a sensing platform, which was purchased from Zensor R&D (Taichung, Taiwan). Figure 1 shows our previous developed biosensor with optimizations to enhance signal detection [17 (link)]. The following materials and reagents were purchased from Sigma-Aldrich (Sigma-Aldrich St. Louis, MO, USA): phosphate-buffered saline (PBS), carboxymethyl dextran sodium salt (CMD-Na), 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC), N-hydroxysulfosuccinimide (NHS), ethanolamine, potassium chloride (KCl), potassium ferricyanide (Fe(CN)₆³⁻), hydrogen peroxide (H₂O₂), 3, 3′, 5, 5′-tetramethylbenzidine (TMB), and diethyl pyrocarbonate (DEPC). NeutrAvidin protein was supplied by Thermo Fisher Scientific (Waltham, MA, USA). Antifluorescein horseradish peroxidase (HRP), a 40,000 dalton protein, was acquired from Abcam (Cambridge, UK). MES-free acid monohydrate, hydroxymethyl-aminomethane (Tris), and ethylenediaminetetraacetic acid (EDTA) were purchased from Amresco (Amresco Inc., Solon, OH, USA). Sodium chloride (NaCl) was obtained from Promega Corporation (Madison, WI, USA). We designed a biotinylated ssDNA probe (bioreceptor probe), fluorescein (FITC) ssDNA probe (detector probe), and artificial mimic targeting sequence using Genomics (Taipei, Taiwan).