ABSTRACT
Objective: To investigate the effect of MeJA combined with high temperature stress in the treatment for the accumulation of triterpenoids in the birch (Betula platyphylla) suspension cells. Methods: After MeJA (25, 50, 100, and 150 μmol/L)and high temperature (50℃ for 2 h) treatment, the cell growth, viability, content of MDA, the activity of defense enzyme, total triterpenoids content, and the gene expression levels of triterpenoids synthesis were measured. Results: The combination of high temperature stress and MeJA treatment had a more powerful positive effect on the synthesis of triterpenoids than single MeJA or high temperature treatment in birch cells. Moreover, the concentration of total triterpenoids had the highest level when adding 150 μmol/L MeJA after the high temperature processing, was up to 76.6 mg/g, which was 81.3%, 159.9% and 13.1% higher than those in the blank control, individual MeJA treatment or the heat treatment alone respectively. Meanwhile, the gene expression levels of SS, SE, BPW, and BPY, related to the triterpenoids synthesis, had an increase about 297.1%, 83.7%, 1 032.6%, and 282.4% compare to the control. The MeJA after high temperature treatment enhanced the activity of SOD and PAL compared with the control, inhibited the cell growth and viability. Conclusion: The treatment of MeJA after high temperature affects the cell growth, viability, and activity of defense enzyme, regulates the genes expression level of triterpenoids synthesis, and eventually could make cells to produce the triterpenoids substance effectively.
ABSTRACT
Chitosan-Ru ( bpy ) 2+3 -SiO2 composite nanoparticles ( CRuS NPs ) were prepared by reverse microemulsion method, and based on the Nafion/MCNT composite membrane technology, CRuS NPs were effectively and steadily immobilize on the surface of a glassy carbon electrode to prepare the electrochemiluminescence sensor for uric acid determination. In 0. 1 mol/L PBS (pH 7. 4) buffer solution, when the actuation duration between uric acid and the modified electrode was 15 min, the electrochemiluminescence showed a good linear relationship to the negative logarithm of uric acid concentration in the range of 1. 0 × 10-10-1. 0 × 10-5 mol/L, the linear equation was IECL=-709. 52-202. 74lgC and the correlation coefficient was 0. 9936 with a detection limit of 6. 0 × 10-12 mol/L. The ECL sensor exhibited excellent repeatability and stability, and the RSD for 11 times determination of 1. 0 × 10-8 mol/L uric acid was 2. 9%. The recovery was 98. 5%-103. 5% in the determination of real Uric acid sample.
ABSTRACT
In this paper, a novel electrochemiluminescent (ECL) detection approach was developed for highly sensitive detection of EGL inhibitors based on the ECL inhibition of Ru(bpy)32+ /2-(Dibutylamino)ethanol (DBAE) system. A microfluidic ECL detection cell was fabricated to couple with the capillary electrophoresis system, the electrochemical system and the post-column injection system. Both Ru(bpy)32+ and DBAE solutions were injected directly to the working electrode surface by a micro-infusion system to obtain a high and stable ECL signal. The performance of this setup was demonstrated by the analysis of two typical ECL inhibitors, dopamine and epinephrine. Under the optimal conditions, the limit of detection (LOD) for dopamine and epinephrine was 50 nM and 5 nM respectively. The proposed method was also successfully used for the trace analysis of dopamine and epinephrine in human serum samples.
ABSTRACT
In this paper, a novel electrochemiluminescent (ECL) detection approach was developed for highly sensitive detection of ECL inhibitors based on the ECL inhibition of Ru(bpy)32+/2-(Dibutylamino)ethanol (DBAE) system. A microfluidic ECL detection cell was fabricated to couple with the capillary electrophoresis system, the electrochemical system and the postcolumn injection system. Both Ru(bpy)32+ and DBAE solutions were injected directly to the working electrode surface by a micro-infusion system to obtain a high and stable ECL signal. The performance of this setup was demonstrated by the analysis of two typical ECL inhibitors, dopamine and epinephrine. Under the optimal conditions, the limit of detection (LOD) for dopamine and epinephrine was 50nM and 5nM respectively. The proposed method was also successfully used for the trace analysis of dopamine and epinephrine in human serum samples.