15n5 2 deoxyadenosine

2′-deoxycytidine (dC, ≥99%), 2′-deoxyadenosine monohydrate (dA·H₂O, ≥ 99%), adenosine (rA, ≥ 99%), and formic acid (for mass spectrometry, ≈ 98%) were purchased from Sigma-Aldrich (St. Louis, MO, USA). 5-methyl-2′-deoxycytidine (5mC) were ordered from Berry & Associates (Dexter, MI). [¹⁵N₅]-2′-deoxyadenosine ([¹⁵N₅]-dA), [¹⁵N₃]-2′-deoxycytidine ([¹⁵N₃]-dC), [D₃]-5-methyl-2′-deoxycytidine ([D₃]-5mC), N⁶-methyladenosine (m⁶A), and [D₃]-L-methionine were obtained from Cambridge Isotope Laboratories (Andover, MA, USA). N⁶-methyl-2′-deoxyadenosine (6mA) was purchased from Santa Cruz Biotechnology, Inc. (Dallas, Texas, USA). [D₃]-N⁶-methyladenosine ([D₃]-m⁶A) was ordered from Toronto Research Chemicals (North York, Ontario, Canada). [¹⁵N₅]-N⁶-methyl-2′-deoxyadenosine ([¹⁵N₅]-6mA) was synthesized and purified in our own lab. Ammonium bicarbonate (NH₄HCO₃) was ordered from Merck KGaA (Darmstadt, Germany). Ultrapure water was produced using ELGA PureLab-water purification system (High Wycombe, Bucks, UK). Crotalus adamanteus venom phosphodiesterase I (SVP) was obtained from Worthington Biochemical Corporation (Lakewood, CO, USA). Deoxyribonuclease I (DNase I) and calf intestinal alkaline phosphatase (CIP) was purchased from New England Biolabs (Ipswich, MA, USA). Other chemicals of at least analytical reagents were used.