Physicochemical and immunological studies on the stability of free and microsphere-encapsulated tetanus toxoid in vitro.
The stability of tetanus toxoid released from experimental, slow-release microsphere vaccines was compared with that of free toxoid under different conditions over a 3 month period. The amount of antigenicity remaining, as measured by ELISA, correlated well with loss of toxoid structure, as determined by circular dichroism and fluorescence spectroscopy. At 37 degrees C and low pH, pH 2.5 for free toxoid, or under the acidic conditions generated by the hydrolysis of fast-release microspheres, a gradual unfolding of the polypeptide chain was observed within the first few weeks with more rapid denaturation beyond 30 days.
Xing
D K
DK
Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, Hertfordshire, UK.
Crane
D T
DT
Bolgiano
B
B
Corbel
M J
MJ
Jones
C
C
Sesardic
D
D
D004355:Drug Stability; D006863:Hydrogen-Ion Concentration; D008863:Microspheres; D013696:Temperature; D013745:Tetanus Toxoid / Q000008:administration & dosage / Q000737:chemistry* / Q000276:immunology
D013745:Tetanus Toxoid