VitriBlast™ contains hSA and it is most likely that DMSO oxidizes into dimers and/or oligomers since it has an oxidative effect and thereby creating disulfide bridges. The reaction is rather slow but, if DMSO and hSA exist together for a longer time, it is likely that these bonds are created.
Every hSA molecule contains a free cystein which could be oxidized. hSA also contains several internal disulphide bridges which can be opened and reclosed in another position, or react with another hSA-molecule (thioldisulphide exchange) due to the effect of DMSO. This could lead to a number of different combinations of hSA with an oligomer of hSA as the result.
Regardless of whether dimers or oligomers are created, hSA is changed to such a degree that it would not function properly as an excipient, since its tertiary structure is so different from native hSA.
In short: DMSO inhibits the function of hSA in the medium, although only if added to VitriBlast™ earlier than just prior to use.
References:
“Recovery and purification of highly aggregation-prone disulfide-containing peptides: application to islet amyloid polypeptide”, Andisheh Abedini, Gagandeep Singh A, Daniel P. Raleigh,
Analytical Biochemistry 351 (2006) 181–186
“Solvation effects in human serum albumin radiolysis in the presence of dimethylsulfoxide”, V.K.Pogorelyi, V. N. Barvinchenko,and V. V. Turov.
Teoreticheskaya i Eksperimental’naya Khimiya 26 (1988 ) 107-110. Translated January-February, 1990. Original article submitted August 18, 1988
