Determination of prostatic fluid citrate concentration using peroxidase-like activity of a peroxotitanium complex.

There have been developed many kinds of methods for detecting citrate in body fluids since citrate is very important physiologically and biochemically. In particular, determination of citrate concentration in prostatic or seminal fluid is useful in early diagnosis of prostate cancer. Recently, a peroxotitanium complex prepared from titanium tetrachloride and hydrogen peroxide has been shown to have peroxidase-like activity which is greatly inhibited by some hydroxyalkanoic acids.

Relationship between enzyme concentration and Michaelis constant in enzyme assays.

The upper bound of enzyme concentration for accurately estimating the parameters in Michaelis-Menten (MM) equation is not completely determined and still under discussion, even though many researchers have investigated the equation's validity for a long time. In the paper, we broadly investigated the correlation between the system of ordinary differential equations for monosubstrate irreversible enzyme reaction (HMM-system) and its derivative MM equation focusing on the relationship between initial enzyme concentration [E] and Michaelis constant K by numerical simulation. According to the results, the initial reaction velocity v is still a function of initial substrate concentration [S] at [E] View Article and Find Full Text PDF