Lc ms grade acetonitrile

GGPP and GGP were purchased from Echelon Biosciences and Larodan, respectively. For HPLC–MS analyses, milli-Q water, LC–MS grade acetonitrile from VWR, and LC–MS grade NH₄OH solution (25%) from Merck were used. For sample preparation, HPLC grade acetonitrile from Merck (Supelco) was employed.

Rats were administered clinical grade Vancomycin hydrochloride (Lot number: 167973; Fresenius Kabi, Lake Zurich, IL, USA), piperacillin-tazobactam sodium (Lot number: 1PU19022; Apollo, Palm Beach Gardens, USA), iohexol [Omnipaque] (Lot number: 15025174; GE Healthcare Inc., Marlborough, MA, USA), and normal saline as a control group (Hospira, Lake Forest, IL, USA). Vancomycin and piperacillin-tazobactam were prepared by weighing and dissolving the powder in purified water (EMD Millipore, Burlington, MA) to achieve final concentrations of 100 mg/mL and 500 mg/mL, respectively. For LCMS analyses, analytical grade iohexol (Lot number: LRAC5648; Sigma-Aldrich, St. Louis, MO), and creatinine (Lot number: LRAB2988; Sigma-Aldrich, St. Louis, MO) were purchased for stock solution preparation; iohexol-d5 (Lot number: LRAC5648; Cayman Chemical, Ann Arbor, MI), and creatinine-d3 (Lot number: 0533175–29; Cayman Chemical, Ann Arbor, MI) were purchased for use as internal standards; LCMS-grade acetonitrile and methanol (VWR, Radnor, PA) were used as mobile phase solvents; formic acid was obtained from Fischer Scientific (Waltham, MA). Frozen, nonimmunized, nonmedicated, pooled plasma (anticoagulated with disodium EDTA) from Sprague Dawley rats (Lot: RAT483100; BioreclamationIVT, Westbury, NY) was utilized for dilution of rat plasma samples.

LC-MS grade formic acid was purchased from Sigma Aldrich Co., St. Louis, MO, USA. LC-MS grade acetonitrile, water, and other (analytical grade) solvents were obtained from VWR International GmbH, Darmstadt, Germany. Dimethyl sulfoxide was purchased from, Carl Roth GmbH, Karlsruhe, Germany.

Analytical TLCs were performed on silica gel plates (Merck, Kieselgel 60F254, 0.25 and 0.5 mm, Merck, Darmstadt, Germany). The spots were visualized by exposure to UV light and/or iodine vapours and/or by spraying with 10% H₂SO₄ in MeOH and with 5% phosphomolybdic acid in EtOH, followed by heating at 110 °C for 10 min. Sigma Aldrich Co. (St. Louis, MO, USA, supplied all reagents and solvents. LC-MS grade acetonitrile, water, and other (analytical grade) solvents were obtained from VWR International GmbH, Darmstadt, Germany. Dimethyl sulfoxide was purchased from, Carl Roth GmbH, Karlsruhe, Germany.

LC–MS grade Acetonitrile (VWR, Radnor, PA, USA) was used, and water purified using a MilliQ Direct 8 system (Merck, Darmstadt, Germany). Glacial acetic acid, perchloric acid 60%, l-proline for biochemistry, trichloroacetic acid, diethyl ether, sodium carbonate anhydrous, and acetone for LC were acquired from Merck (Darmstadt, Germany). Ammonium formate, formic acid, dansyl chloride, and 1,7-diaminoheptane were purchased from Sigma-Aldrich (St. Louis, MO, USA). All certified materials, including histamine dihydrochloride, tyramine hydrochloride, cadaverine dihydrochloride, putrescine dihydrochloride, spermidine trihydrochloride, and spermine tetrahydrochloride, were purchased from Dr. Ehrenstorfer GmbH (Augsburg, Germany). Other chemicals, including sodium hydroxide micropills, were obtained from POCH (Gliwice, Poland). Ammonium acetate for HPLC was supplied by J.T. Baker (Deventer, The Netherlands).