## Doctoral Dissertations

Winter 1996

Dissertation

Biochemistry

#### Degree Name

Doctor of Philosophy

The analytical electrophoresis apparatus (AEA) is capable of generating and monitoring the electrophoretic migration of macroions. The oligonucleotide pd(A)$\sb{20}\cdot$pd(T)$\sb{20}$ was use as a model to compound to evaluate the range and validity of AEA measurements under a variety of electric fields and solvent conditions. A broad range of electric fields yield consistent, reproducible values. The charge determination from different procedures, steady state electrophoresis (SSE) and electrophoretic mobility, have not been consolidated into a consistent theory but advancements in the scope and understanding of the AEA's potential have been made. The apparent charge from the AEA measured electrophoretic mobility, $\mu$, of Pd(A)$\sb{20}\cdot$pd(T)$\sb{20}$ shows more sensitivity to solution conditions (different chloride salts or ionic strength in a buffer of 20 mM Tris, pH 8.0, at 20$\sp\circ$C) than the SSE determined Q$\sb{\rm app}$. The electrophoretic mobility of pd(A)$\sb{20}\cdot$pd(T)$\sb{20}$ increases with decreasing ionic strength (100 nM KCl to 20 mM KCl salt conditions) and show a direct relationship (possibly coupled flow) to the mobility (and the cation affinity to DNA) of the different chloride salt (Li$\sp+$, Na$\sp+$, K$\sp+$, and (CH$\sb3$)$\sb4$N$\sp{\cdot+}$). The combined SSE data (global nonlinear fit of all fields, one solution condition) suggest a single value for the apparent charge of around 5 e (electron units).