Based Mobile Electrophoresis Of The Reaction Interface And Titration New Principles And New Methods

In resent years, Moving Reaction Boundary (MRB) theoretical and experimental study is developing rapidly. The concept of MRB is very useful in the field of electrophoresis. For example, the dynamic theory of isoelectric focusing (IEF) has been well developed from the concept of MNB. Second, the method of MNB has been used for the sample stacking of zwitterions (viz., proteins, or peptides, or amino acids) and drugs in capillary electrophoresis (CE) and condensation of target compound in free-flow electrophoresis (FFE). Third, the concept of MCB has been applied for the illumination on mechanism of EDTA-based sample sweeping of heavy metal ions in CE.This paper for the first time shows that the concept of MRB can be used to design a novel acid-base titration of EABT via the MNB formed with H+ and OH-For the purpose of simplicity, we use HC1 and NaOH, HAc and NaOH as the model reactant and reagent, respectively, for the studies. Below are the relevant experiments and advantages of EABT. The main points of this thesis are summarized as follows:1. The equipment of the EABTIn the Chapter 2, The apparatus used for the experiment of EABT is connected a glass tube which connected with the anode electrophoresis slots (acid solution) and cathodic electrophoretic slots (bace solution). Under the electric field, the hydrogen and hydroxyl ions moved in the opposite direction and had an electromigration reaction with each other. The reaction led to the formation of MNB. The tube coupled with a ruler was set on a white light plate, an adjustable digital camera was fixed over the flat plate. The digital camera could be well used to record the boundary movement. The two ends of the glass tube were connected to two three-way-pipes via the two rubber-tubes. The two pipes were further joined with two peristaltic pumps and the two vials of anode and cathode. The two pumps were used for the flows of anolyte and catholyte. A power supply was used to yield the direct electric field for the experiment of EABT.2. Equivalence-Point Electromigration strong Acid-strong Base Titration via Moving Neutralization Boundary ElectrophoresisIn the Chapter 3, we developed a novel method of acid-base titration, viz., the electromigration acid-base titration (EABT), via the apparatus of EABT was described in Chapter 2. With HCl and NaOH as the model strong acid and base, respectively, we conducted the experiments on the EABT via the method of MNR for the first time. The experiments revealed that (1) the concentration of agarose gel, the voltage used and the content of background electrolyte (KCl) had evident influence on the boundary movement; (2) the movement length was as a function of the running time under the constant acid and base concentrations; and (3) there was a good linearity between the length and natural logarithmic concentration of HCl under the optimized conditions, and the linearity could be used to detect the concentration of acid. The experiments further manifested that (1) the RSD values of intra-day and inter-day runs were less than 1.59% and 3.76%, respectively, indicating good precision and stability; (2) the indicators with different pKa values had no obvious effect on EABT, distinguishing strong influence on the judgment of equivalence-point titration in the classic one; and (3) the constant equivalence-point titration was always existed in the EABT, rather than the classic volumetric analysis. Additionally, the EABT could be well used for the determination of actual acid concentrations. The experimental results achieved herein showed a new general guidance for the development of classic volumetric analysis and element (e.g., nitrogen) analysis in protein chemistry.3. Equivalence-Point Electromigration weak Acid-strong Base Titration via Moving Neutralization Boundary ElectrophoresisIn the Chapter 4, we used HAc and NaOH as the model weak acid and strong base, respectively via the EABT. The experiments revealed that (1) the concentration of agarose gel, the voltage used and the content of background electrolyte (KC1) had evident influence on the boundary movement; (2) the movement length was as a function of the running time under the constant acid and base concentrations; and (3) there was a good linearity between the length and concentration of HAc under the optimized conditions, and the linearity could be used to detect the concentration of acid. (4) the indicators with different pKa values had no obvious effect on EABT, distinguishing strong influence on the judgment of equivalence-point titration in the classic one.