RESUMO
A derivatization method for the determination of oligosaccharides with high sensitivity by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry(MALDI-TOF-MS) based on a labeling regent 1-(4-Cyanophenyl)-4-piperidinecarbohydrazide(CPH) was proposed. The hydrazones were generated by the reaction of the reducing ends of oligosaccharides and the hydrazide of CPH. The derivatives were directly analyzed by MALDI-TOF-MS. Reaction conditions such as reaction temperature, concentration of acetic acid and excess ratio of CPH regent were optimized. When the oligosaccharides reacted with 100 time excess of CPH at 100 ℃ and in 0.125% acetic acid (V/V), the yield was highest. The results showed the derivatization with CPH increased the sensitivity of MS detection and this method was suitable for the analysis of oligosaccharides′ compositions.
RESUMO
Before and after zinc and micro-nutrients supplement the changes of intelligence and growth in 108 healthy children aged 7~8yrs were studied.The children were randomly divided into 3 groups:zinc supplement(Z),zinc+micronutrients supplement(Z+M),and micronutrients supplement(M),Before the supplements,hair Zn contemt of children was 2 28?0 74?mol/g and 22 22% of the hair Zn content was lower than 1 68?mol/g?There was a positive correlation between intelligence quotient(IQ) and hair Zn content .After supplement,there were no significant changes among the 3 groups on hair Zn content .The changes of IQ and cognition in Z+M group and M group were significantly higher than Z group,and there was no significant difference between Z+M group and M group.The change of knee height in Z+M group was markedly higher than M group and Z group,while M group was sgnificantly higher than Z group.The results demonstrated that zinc deficiency might not be the main factor that affects the intelligence and growth children,perhaps other micronutrients deficiency should be paid more attention.The simultaneous supplement of zinc and micronutrients may promote the intelligence and growth of children.