Enhancing radiolytic stability upon concentration of tritium‐labeled pharmaceuticals utilizing centrifugal evaporation

Abstract

Tritium radiopharmaceuticals are often used in drug development because of their desirable specific activity. The inherent instability of these radioactive tracers often leads to a requirement to purify prior to use. Purification methodologies such as preparative chromatography and solid/liquid extractions often utilize water as a solvent, which is not suitable for long-term storage and necessitates removal. Rotary evaporation has traditionally been utilized for the removal of this unwanted solvent, however, this method has been shown to lead to decomposition of the tritium species in some cases. Centrifugal evaporation is a milder concentration method which has been demonstrated to effectively remove solvents. In this study, we show that centrifugal evaporation leads to effective concentration of tritium samples without the decomposition typically observed by rotary evaporation.

Enriched chitosan nanoparticles loaded with siRNA are effective in lowering Huntington's disease gene expression following intranasal administration

“…This procedure rapidly removed solvent while the samples themselves were not heated to damaging temperatures. With centrifugal evaporation, particles do not undergo physical stress and in the concentrated state, nanoparticles are kinetically frozen and there is no dynamic exchange of the individual polymer chains, as the movement of the active agents inside and outside of the polymer aggregate is restrained (17).…”

Moisture determination of tritium tracers utilizing near‐infrared spectroscopy

“…The introduction of a suitable solvent such as ethanol for tritium tracer storage typically occurs following a reversed phase purification. Removal of the organic/aqueous mobile phase prior to reconstitution can be achieved via several routes; however, not all are efficient in removing the aqueous portion completely . Ensuring thorough removal of the aqueous phase is essential as it too can have a negative impact on tritium tracer stability.…”

“…Removal of the organic/aqueous mobile phase prior to reconstitution can be achieved via several routes; however, not all are efficient in removing the aqueous portion completely. 2 Ensuring thorough removal of the aqueous phase is essential as it too can have a negative impact on tritium tracer stability. The presence of even small amounts of residual water can lead to the formation of tritiated water because of proton/tritium exchange would be unfavorable for specific biological studies.…”