Antibacterial peptides mixture purified from Ovotransferrin by pepsin digest was used as the raw material. Peptide sections with good antibacterial activity were determined after bacteriostasis experiments, its molecu...Antibacterial peptides mixture purified from Ovotransferrin by pepsin digest was used as the raw material. Peptide sections with good antibacterial activity were determined after bacteriostasis experiments, its molecular weight and amino acid composition were analyzed. The results of experiments indicate that with Sephadex G-50 and distilled water as mobile phase, detection wavelength 220 nm, flow rate 1.5 mL/min, sample density 0.2 g/mL, and volume 0.2 mL are the optimal conditions. Bacteriostasis experiments of the fraction of purified peaks were carried out and the result was： peak 1peak 3peak 2; the molecular weight of peak 1 was about 3015 by high performance liquid chromatography; active peptide possessed positive charges by amino acid analysis, its cationic characteristics are in accordance with the nature of antimicrobial peptides.展开更多
CdTe nanocrystals were prepared in aqueous solution via the reaction between Cd^2＋ and NaHTe in the presence of mercaptoacetic acid. Interactions between CdTe nanocrystals and phenylalanine were formed via electrosta...CdTe nanocrystals were prepared in aqueous solution via the reaction between Cd^2＋ and NaHTe in the presence of mercaptoacetic acid. Interactions between CdTe nanocrystals and phenylalanine were formed via electrostatic/coordinate self-assembly. The photoluminescence intensity of CdTe nanocrystals was improved obviously. The interaction mechanism was discussed and was considered to be surface passivation.展开更多
Objective： To optimize the ELISA for the determination of tetrodotoxin. Methods： A competitive enzyme-linked immunosorbent assay （ELISA） was used. In the ELISA, 100 μl antigen （1. 0 μg/ml） was coated on the mi...Objective： To optimize the ELISA for the determination of tetrodotoxin. Methods： A competitive enzyme-linked immunosorbent assay （ELISA） was used. In the ELISA, 100 μl antigen （1. 0 μg/ml） was coated on the microtiter plate for 60 min at 37 C or over night at 4 C. The plate was then washed 3 times with PBS-T for 3-5 s each time. The optimal incubation time for monoclonal antibody （mAb）, goat anti-mice IgG peroxidase conjugate and OPD were 30 min, 20 min and 10 min at 37 C, re- spectively. Results.. The detection limit is 0. 05 ng in each well. The curve was linear for TTX doses be- tween 5-5 000 ng/ml （0. 25-250 ng for every assay）. The linear regress equation was Y = 0. 30 88X-0.17 41 （R=0.99 01）. The average callback for TTX of muscles and gonads were 99.74% and 100.30%, respectively. The sensitivity of optimization ELISA was 5 times than traditional method and the time of 1.8 h were saved. Conclusion： The optimized ELISA is an ideal method for the determination of tetrodotoxin.展开更多
基金Supported by the Applied Basic Fund of Jilin Provincial Science and Technology Department(No.20070572)the Frontiers of Science of Jilin University and Innovation Fund of Interdisciplinary, China(No.200903224)
文摘Antibacterial peptides mixture purified from Ovotransferrin by pepsin digest was used as the raw material. Peptide sections with good antibacterial activity were determined after bacteriostasis experiments, its molecular weight and amino acid composition were analyzed. The results of experiments indicate that with Sephadex G-50 and distilled water as mobile phase, detection wavelength 220 nm, flow rate 1.5 mL/min, sample density 0.2 g/mL, and volume 0.2 mL are the optimal conditions. Bacteriostasis experiments of the fraction of purified peaks were carried out and the result was： peak 1peak 3peak 2; the molecular weight of peak 1 was about 3015 by high performance liquid chromatography; active peptide possessed positive charges by amino acid analysis, its cationic characteristics are in accordance with the nature of antimicrobial peptides.
基金Supported by the Major Foundation of Chinese Academy of Sciences(No. 2002CD713802) and the National High TechnologyDevelopment Program of China(No. 2002AA302203)
文摘CdTe nanocrystals were prepared in aqueous solution via the reaction between Cd^2＋ and NaHTe in the presence of mercaptoacetic acid. Interactions between CdTe nanocrystals and phenylalanine were formed via electrostatic/coordinate self-assembly. The photoluminescence intensity of CdTe nanocrystals was improved obviously. The interaction mechanism was discussed and was considered to be surface passivation.
基金the grants from PhD Priming Foundation of Jilin University(430505010276)
文摘Objective： To optimize the ELISA for the determination of tetrodotoxin. Methods： A competitive enzyme-linked immunosorbent assay （ELISA） was used. In the ELISA, 100 μl antigen （1. 0 μg/ml） was coated on the microtiter plate for 60 min at 37 C or over night at 4 C. The plate was then washed 3 times with PBS-T for 3-5 s each time. The optimal incubation time for monoclonal antibody （mAb）, goat anti-mice IgG peroxidase conjugate and OPD were 30 min, 20 min and 10 min at 37 C, re- spectively. Results.. The detection limit is 0. 05 ng in each well. The curve was linear for TTX doses be- tween 5-5 000 ng/ml （0. 25-250 ng for every assay）. The linear regress equation was Y = 0. 30 88X-0.17 41 （R=0.99 01）. The average callback for TTX of muscles and gonads were 99.74% and 100.30%, respectively. The sensitivity of optimization ELISA was 5 times than traditional method and the time of 1.8 h were saved. Conclusion： The optimized ELISA is an ideal method for the determination of tetrodotoxin.
