Table II.
Experimentala and Theoretical Collision Cross-Section (CCS) Increments for Isoforms D1–D4 of T-DM1
| Experimental and theoretical CCSsbc (Å2) | ΔCCs : theoretical increments from molecular modeling measured with Mobcal (Å2) | ||||||
|---|---|---|---|---|---|---|---|
| Dn | IM-MSd data | Measured from MWsd | Positional isoform (Pi) | Scaled PA | Average scaled PA | EHSS | Average EHSS |
| D1 | 7453 ± 8 (+19) | 6777 (+30) | Pi1 | 62 | 88 | 71 | 92 |
| Pi2 | 82 | 66 | |||||
| 7500 ± 0 | 6852 (+30) | Pi3 | 57 | 56 | |||
| Pi4 | 53 | 177 | |||||
| D2 | 7472 ± 0 (+19) | 6806 (+29) | Pi1 + Pi2 | 136 | 184 (+96) | 189 | 2.09 (+117) |
| Pi1 + Pi3 | 151 | 184 | |||||
| Pi1 + Pi4 | 219 | 254 | |||||
| 7522 ± 8 (+22) | 6881 (+29) | Pi2 + Pi3 | 192 | 192 | |||
| Pi2 + Pi4 | 208 | 243 | |||||
| Pi3 + Pi4 | 197 | 195 | |||||
| D3 | 7504 ± 8 (+32) | 6836 (+30) | Pi1 + Pi2 + Pi3 | 270 | 328 (+144) | 260 | 3.31 (+122) |
| Pi1 + Pi2 + Pi4 | 343 | 360 | |||||
| 7549 ± 8 (+27) | 6910 (+29) | Pi2 + Pi3 + Pi4 | 367 | 345 | |||
| Pi1 + Pi3 + Pi4 | 334 | 358 | |||||
| D4 | 7527 ± 0 (+23) | 6865 (+29) | Pi1+Pi2+Pi3+Pi4 | 402 | 402 (+74) | 398 | 3.98 (+67) |
| 7571 ± 8 (+22) | 6939 (+29) | ||||||
a
Experimental values were obtained from the 23+ charge state by IM-MS on deglycosylated and glycosylated samples.
b
The ΔCCSs per additional payload are indicated in brackets.
c
The values obtained from untreated samples are shown in bold.
d
CCS = 2.435 × M2/3; uncertainty values represent the variability as a result of repeat of injections (n = 3).