Figure 1.
The MALDI-TOF-MS spectra of mPEG1000-COOH (A) and mPEG1000-HCPT (B).
Notes: The average molecular weight of mPEG1000-COOH was shown to be 1,051.3 Dalton, while the average molecular weight of mPEG1000-HCPT was 1,397.3 Dalton, with the subtraction of 346 Dalton.
Abbreviations: HCPT, 10-hydroxycamptothecin; MALDI-TOF-MS, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry; PEG, polyethylene glycol.