Protecting fibrinogen with rutin during UVC irradiation for viral inactivation

Fibrinogen solutions were irradiated with WC (254 mn) to inactivate contaminating viruses, In order to protect fibrinogen during UVC irradiation, 0.5 mM rutin was added prior to UVC exposure and subsequently removed during processing, Viral kill by 0.1 J/cm(2) UVC resulted in the following inactivation values (log 10): non-lipid-enveloped viruses: Parvo greater than or equal to 5.5; encephalomyocarditis virus greater than or equal to 6.5; hepatitis A virus greater than or equal to 6.5: lipid-enveloped viruses: human immunodeficiency virus greater than or equal to 5.7; vesicular stomatitis virus greater than or equal to 5.7. Fibrinogen irradiated with 0.5 mM rutin did not significantly differ from unirradiated material in terms of clot time and breaking strength, In the absence of rutin, UVC irradiation of fibrinogen at similar fluence led to loss of solubility, increased clot time and the cleavage of fibrino-peptides that reacted with dinitrophenyl hydrazine as a test for ketonic carbonyl groups. High-performance liquid chromatography and mass spectrometry data showed that rutin exposed to UVC formed numerous breakdown, oxidation and combinational products, Experiments with H-3-rutin showed that after UVC irradiation, subsequent processing by a C18 resin and alcohol precipitation removed >99% rutin, representing <10 ppm rutin in the final fibrinogen preparations, Residual H-3-rutin was not covalently bonded to the fibrinogen, Immunochemical studies with rabbit antisera to UVC irradiated (with rutin) fibrinogen showed the absence of neoimmungens. By all measures, rutin prevents fibrinogen degradation during virucidal UVC irradiation.