Albumin-bound low molecular weight thiols analysis in plasma and carotid plaques by CE.
We describe a new method for the quantification of low molecular weight thiols, as homocysteine, cysteine, cysteinylglycine, glutamylcysteine and glutathione bound to human plasma albumin. After albumin isolation and purification by SDS-PAGE, thiols were freed from protein with tri-n-butylphosphine and successively derivatized with 5-iodoacetamidofluorescein. Samples were then injected and quantified in about 18 min by CE with laser induced fluorescence detection. Precision tests indicate a good repeatability of the method both for migration times (RSD<0.63%) and areas (RSD<2.98%). The method allows to measure all five low molecular weight thiols released from just 3 microg of albumin thus improving the other described methods in which only three or four thiols were detected. Due to the elevated sensitivity (LOD of 0.3 pM for all thiols), also low molecular weight thiols bound to albumin filtered in tissues could be quantified.
Zinellu
Angelo
A
Dept. Biomedical Sciences, University of Sassari, Sassari, Italy. angelozinellu@libero.it
Lepedda
Antonio
A
Sotgia
Salvatore
S
Zinellu
Elisabetta
E
Marongiu
Giommaria
G
Usai
Maria Franca
MF
Gaspa
Leonardo
L
De Muro
Pierina
P
Formato
Marilena
M
Deiana
Luca
L
Carru
Ciriaco
C
D000418:Albumins / Q000737:chemistry / Q000378:metabolism*; D016893:Carotid Stenosis; D019075:Electrophoresis, Capillary / Q000379:methods*; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D005452:Fluoresceins / Q000737:chemistry; D006801:Humans; D057230:Limit of Detection; D008970:Molecular Weight; D013438:Sulfhydryl Compounds / Q000097:blood* / Q000737:chemistry
D000418:Albumins; D005452:Fluoresceins; D013438:Sulfhydryl Compounds; C015296:5-iodoacetamidofluorescein