| LC-DAD, 278.4 nm, unstressed control, method M02, file 26708002 | Retention time 20.415 min; verapamil peak area 202.7; reference |
|---|---|
| LC-DAD, 278.4 nm, acid, injection 1, file 26708003 | Retention time 32.250 min; verapamil peak area 203.3; dilution-corrected expected area 200; no change |
| LC-DAD, 278.4 nm, acid, injection 2, file 26708004 | Retention time 33.323 min; verapamil peak area 198.6; dilution-corrected expected area 200; no change |
| LC-DAD, 278.4 nm, mild base, file 26708005 | Retention time 33.923 min; verapamil peak area 198.5; dilution-corrected expected area 184; no loss |
| LC-DAD, 278.4 nm, heated base, file 26708009 | Retention time 34.759 min; verapamil peak area 235.6; dilution-corrected expected area 184; apparent change +28 % |
| LC-DAD, 278.4 nm, thermal, file 26708010 | Retention time 35.195 min; verapamil peak area 244.7; dilution-corrected expected area 200; apparent change +22 % |
| LC-DAD, 278.4 nm, neutral oxidative, unheated, file 26708006 | Retention time 34.406 min; verapamil peak area 105.0; dilution-corrected expected area 200; change −48 %; verapamil N-oxide retention time 36.596 min, peak area 102.6; summed area 207.6; recovery 104 % |
| LC-DAD, 278.4 nm, neutral oxidative, 60 °C for 100 min, file 26708007 | Retention time 34.711 min; verapamil peak area 18.4; dilution-corrected expected area 200; change −91 %; verapamil N-oxide retention time 36.886 min, peak area 171.3; summed area 189.7; recovery 95 % |
| LC-DAD, 278.4 nm, acidified oxidative, 60 °C for 2 h, file 26708008 | Retention time 34.841 min; verapamil peak area 171.9; dilution-corrected expected area 193; change −11 %; verapamil N-oxide not detected; D617 retention time 23.5 min |
| LC-DAD, heated neutral oxidative | Condition-specific peak retention time 53.339 min; area 24.1; symmetry 1.716 |
Sean Chen, Karl Zhao. “pH-dependent divergence of oxidative degradation pathways in verapamil hydrochloride: a forced-degradation study by LC-UV and high-resolution Orbitrap mass spectrometry.” ChemRxiv (). https://doi.org/10.26434/chemrxiv.15007682/v1
Four mass spectra supplied as PNG files in the additional supporting information were not transcribed
| HRMS (ESI+), verapamil [M+H]⁺ | C₂₇H₃₉N₂O₄⁺; theoretical m/z 455.2904; observed m/z 455.3125, uncorrected; error +48.5 ppm, lock mass; all conditions |
|---|---|
| HRMS (ESI+), verapamil N-oxide [M+H]⁺ | C₂₇H₃₉N₂O₅⁺; theoretical m/z 471.2853; observed m/z 471.2858; error +1.1 ppm; neutral oxidative |
| HRMS (ESI+), norverapamil [M+H]⁺ | C₂₆H₃₇N₂O₄⁺; theoretical m/z 441.2748; observed m/z 441.2754, recalibrated; error +1.4 ppm; neutral oxidative |
| HRMS (ESI+), D617 [M+H]⁺ | C₁₇H₂₇N₂O₂⁺; theoretical m/z 291.2067; observed m/z 291.2064, recalibrated; error −1.0 ppm; acidified oxidative |
| HRMS (ESI+), uncorrected norverapamil [M+H]⁺ | Theoretical m/z 441.2748; observed m/z 441.2968; error +49.9 ppm |
| HRMS (ESI+), uncorrected D617 [M+H]⁺ | Theoretical m/z 291.2067; observed m/z 291.2205; error +47.4 ppm |