Identification of adsorbed protein films by exposure to antisera and water vapor

Drops of various antisera against human proteins were placed onto hydrophilic or hydrophobic surfaces that had adsorbed human proteins. The rinsed and dried plates were exposed to water vapor. Wherever an antiserum droplet had resided on a matching protein film, vapor scattered least light, indicating greatest wetting. The protein deposited within 5 seconds by plasma onto glass proved to be fibrinogen.