Micromethod for Estimation of Serum Adenosine Deaminase.

METHOD for the miieasureniemit of seiummmadenosiime deaminase activity was recently published in this ,Journal (1). This method requires 2 ml. of serum, suffers froni ammunnecessarily large number of manipulations, ahl(l utilizes aim unstable, relatively insensitive Nessler color reaction (2). Attempts to overcome these difficulties constitute the basis for this report. A catalyzed indopheimol reaction for the determination of ammonia, wimicim is reportedly quite sensitive amid produces a stable blue color, has been published by Chammev amid Marbach (3). These authors have applied the reaction to the determilmation of urea after hydrolysis with urease, and reagents ale available comniercially. It is a modification of the Bertholet reaction (4). The following is a description of the application of this reactiolm to the determination of ammonia liberated by serunm adellosimle deammase activity.