E. Kaale et al., Electrophoretically mediated microanalysis of gentamicin with in-capillaryderivatization and UV detection, ELECTROPHOR, 22(13), 2001, pp. 2746-2754
This paper describes a system for integration of a one-step-microscale chem
ical derivatization and analysis by a methodology known as electrophoretica
lly mediated microanalysis (EMMA). Differential electrophoretic mobility be
tween an analyte, reagent, and their product offers EMMA a unique capabilit
y to selectively carry out electrophoretic mixing, control product formatio
n, and separation. This system was successfully applied to perform derivati
zation and separation of the multicomponent aminoglycoside antibiotic genta
micin using 1,2-phthalic dicarboxaldehyde and mercaptoacetic acid as labeli
ng reagents. A multivariate approach based on central composite experimenta
l design was used to optimize the derivative yield. Full automation of the
derivatization and analytical procedure, high derivatization efficiency, hi
gh Sample throughput, and precision are the excellent features of the prese
nt method. in addition, this methodology offers short analysis time, as wel
l as selectivity and sensitivity suitable for impurities determination. Sep
aration of gentamicin C-1, C-1a, C-2, C-2a, C-2b, sisomicin, and several mi
nor components was achieved. For the first time separation and identificati
on of three impurities, namely garamine, 2-deoxystreptamine, and paromamine
are described.