Identification of the modifying sites of mono-PEGylated salmon calcitonins by capillary electrophoresis and MALDI-TOF mass spectrometry.
A capillary electrophoretic method (CE) was developed for the determination of the PEG-modification sites of three positional isomers of mono-PEG modified salmon calcitonins (mono-PEG-sCTs). Resistance to proteolytic degradation on the PEG modification sites resulted in different patterns of CE electropherograms for the tryptic digested mono-PEG-sCTs isomers, and the PEG modification sites were assigned accordingly. The PEG-modification sites were also confirmed directly by determining the molecular masses of the tryptic digested PEG-modified fragments of respective mono-PEG-sCT by the matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry.
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Drug Targeting Laboratory, College of Pharmacy, SungKyunKwan University, Suwon, South Korea.
Park
M O
MO
Choi
S Y
SY
Kim
Y S
YS
Lee
S S
SS
Yoo
S D
SD
Lee
H S
HS
Lee
K C
KC
D000595:Amino Acid Sequence; D001665:Binding Sites; D002116:Calcitonin / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods; D007536:Isomerism; D008969:Molecular Sequence Data; D011092:Polyethylene Glycols / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014357:Trypsin
D011092:Polyethylene Glycols; C028815:salmon calcitonin; D002116:Calcitonin; D014357:Trypsin