The secondary antibody, a polyclonal anti-mouse IgG from sheep (catalog no. R1256P, lot 21481, 2.2 mg/ml), was obtained from Acris Antibodies (Herford, Germany).
Cocaine hydrochloride, cryst, extra pure, L55041262 was obtained from Merck, KL3aA, 64271, Darmastadt, Germany. Benzoylecgonine (tetrahydrate), batch 02-D-23 was obtained from National Measurement Institute, North Ryde, NSW, 1670, Australia. …show more content…
N,N –dicyclohexylcarbodiimide (DCC, puriss), tetrabutylammonium borohydride (purum, ≥97%) , hydrogen peroxide solution ≥30% (TraceSELECT®) were from Fluka (Sigma-Aldrich, Taufkirchen Germany). The following chemicals were also purchased from Sigma-Aldrich: N-hydroxysuccinimide (NHS, 98%) N, N-dimethylformamide (DMF, ≥99.5%), sodium phosphate dibasic dehydrate (purum p.a.), sodium phosphate monobasic dihydrate (BioUltra, ≥99%), sodium chloride (BioUltra, ≥99.5%), potassium phosphate monobasic (BioUltra, ≥99.5%), potassium phosphate dibasic (BioUltra, 99%), potassium sorbate (purum p.a.), for the preparation of buffers. Additional, TweenTM 20 (pure) and 3,3_,5,5_-tetramethylbenzidine (TMB, research grade) were also obtained from Serva. GuardianTM Peroxidase Conjugate Stabilizer/Diluent was obtained from Toronto Research Chemicals (North York, Canada). Sulfuric acid 95–97% (both Baker-analyzed grade), isopropanol (Baker HPLC analyzed) and methanol (HPLC gradient grade) were purchased from Mallinckrodt Baker (Griesheim, Germany). Ethyl acetate and NaHCO3 were supplied by Merck KGaA (Darmstadt,