A novel ultraviolet illumination used in riboflavin photochemical method to inactivate drug-resistant bacteria in blood components.

BACKGROUND

Ultraviolet (UV) fluorescent lamp (FL) was applied in mainstream riboflavin photochemical method (RPM) to inactivate pathogens in blood components. Low UV irradiance emitted by UV-FL resulted in more time to achieve effective inactivation.

MATERIALS AND METHODS

A novel light emitting diode (LED) UV illumination with adjustable irradiance was developed by us. Two strains of drug-resistant bacteria (DRB), pan-drug resistant Acinetobacter baumannii (PDRAB) and methicillin-resistant Staphylococcus aureus (MRSA) were cultured and used for evaluating the inactivation effectiveness of RPM using UV-LED or UV-FL against DRB in plasma or platelets. Three plasma factors and four platelet parameters were measured after treatments.

RESULTS

There was a linear relationship between UV-LED irradiance and electric current, the minimum UV irradiance was 24 mW/cm, and the maximum was 258 mW/cm. At the same UV dose of 15 J/cm, inactivation effectiveness of UV-LED with 258 mW/cm against PDRAB in plasma or platelets were comparable to that of UV-FL with 16 mW/cm, both above 98%. UV-FL treatment required 10-15 min, but UV-LED only required 1-2 min. However, MRSA showed a resistance to UV-LED (inactivation effectiveness was around 40%) compared with UV-FL (inactivation effectiveness was above 98%). The retention of fibrinogen, factor V, factor VII in plasma and platelet counts in platelets with UV-LED treatment were significantly higher than UV-FL at the same UV dose.

CONCLUSION

The treatment of RPM using UV-LED with high UV irradiance was able to dramatically shorten inactivation time against PDRAB in plasma or platelets and improve retention of blood components compared with UV-FL.