The efficiency of cross-linking methods in eradication of bacteria is influenced by the riboflavin concentration and the irradiation time of ultraviolet light
2014 (English)In: Acta Ophthalmologica, ISSN 1755-375X, E-ISSN 1755-3768, Vol. 92, no 7, p. 656-661Article in journal (Refereed) Published
Abstract [en]
Purpose: To determine bacterial eradication using numerous riboflavin concentrations and different ultraviolet light A (UVA) radiant and exposure time in an experimental model.
Methods: Dilutions of Staphylococcus epidermidis were mixed with riboflavin at varying concentrations (0.007-0.09%). Effects on bacterial growth were evaluated after 0, 3, 6, 30 and 60min of UVA exposure (irradiance 30 and 3mW/cm(2)). Standard settings of UVA were compared with high-power UVA approach. Different fluid thicknesses of the exposed dilutions were also examined to improve the model.
Results: Bacterial eradication (%) was increased after 60 compared with 30min of UVA exposure for concentrations of 0.03-0.07% but not for 0.09% riboflavin. There was a significant difference between the efficacy between 0.03 and 0.09% and eradication dropped from 80% to 50% (p=0.01). A correlation could be calculated for the amount of riboflavin at 60min of UVA and the ability to kill bacteria (p=0.01). The antibacterial effect was more pronounced when the tested bacterial suspension thickness was reduced. High-power UVA method was less potent in microbial elimination, eradicating only 60% of bacteria after 6min versus 97-99% after 60min in the low-power setting, compared with respective controls (p=0.02).
Conclusions: In these in vitro experiments, a longer UVA exposure time in combination with lower riboflavin levels were found to be favourable in killing bacteria as compared to the standard cross-linking settings. Further studies are needed to evaluate the clinical relevance of these findings.
Place, publisher, year, edition, pages
Hoboken, USA: John Wiley & Sons, 2014. Vol. 92, no 7, p. 656-661
Keywords [en]
Bacteria, cross-linking, exposure time, riboflavin, UVA
National Category
Ophthalmology
Identifiers
URN: urn:nbn:se:oru:diva-39452DOI: 10.1111/aos.12301ISI: 000344162700030PubMedID: 25493311Scopus ID: 2-s2.0-84887264034OAI: oai:DiVA.org:oru-39452DiVA, id: diva2:770391
Note
Funding Agency:
Örebro University Hospital (Sweden) - Research Funds OLL-120691
2014-12-102014-12-102020-12-01Bibliographically approved