Maphanga, Charles PManoto, Sello LOmbinda-Lemboumba, SaturninOsualale, OMthunzi-Kufa, Patience2019-04-102019-04-102019-03Maphanga, C.P., Manoto, S.L., Ombinda-Lemboumba, S., Osualale, O. & Mthunzi-Kufa, P. 2019. Near infrared femtosecond laser-induced bacterial inactivation. In: Proceedings Volume 10876, Optical Interactions with Tissue and Cells XXX; 108760K (1 March 2019), SPIE Photonics West Conference, California, USA. From 02-07 February 2019.https://www.spiedigitallibrary.org/conference-proceedings-of-spie/10876/108760K/Near-infrared-femtosecond-laser-induced-bacterial-inactivation/10.1117/12.2509806.full?SSO=1https://doi.org/10.1117/12.2509806http://hdl.handle.net/10204/10942Proceedings Volume 10876, Optical Interactions with Tissue and Cells XXX; 108760K (1 March 2019), SPIE Photonics West Conference, California, USA. From 02-07 February 2019. Due to copyright restrictions, the attached PDF file only contains the abstract of the full-text item. For access to the full-text item, please consult the publisher's website. While waiting for the post-print or published PDF document from the publisherThe use of light to inactivate microbes as an alternative method to the traditional methods of controlling microorganisms continues to draw the attention of researchers. Traditional methods of sterilization and/or pasteurization using chemicals or thermal treatments have certain limitations such as the creation of resistant bacterial strains. The application of pulsed laser irradiation compromises the physiological function of cells, and the degree of destruction is both dose and strain dependent, ranging from reduced cell growth to a complete loss of cell metabolic activity and finally to physical disintegration. This study aimed at using a range of power densities to investigate inactivation of Escherichia coli and Salmonella enteritidis. A Titanium sapphire pulsed laser at 800 nm wavelength, repetition rate of 76 MHz, pulse duration of 120 fs, output power of 560 mW was used in this study. A fluence range was applied on bacterial cultures in a 16 mm diameter petri with a beam spot area of 2.5 cm2 (after expansion). The laser killing effectiveness was evaluated by comparing colony forming units (CFUs) with and without irradiation on 10-7 dilutions of bacterial cultures. Cytotoxicity was analysed using the lactose dehydrogenase (LDH) assay. The laser killing rate varied with bacteria species or strains and the level of fluence.enBacteriaColony forming unitsEscherichia coliFemtosecondGaussian beamNear infraredSalmonella enteritidisConference PresentationMaphanga, C. P., Manoto, S. L., Ombinda-Lemboumba, S., Osualale, O., & Mthunzi-Kufa, P. (2019). Near infrared femtosecond laser-induced bacterial inactivation. SPIE. http://hdl.handle.net/10204/10942Maphanga, Charles P, Sello L Manoto, Saturnin Ombinda-Lemboumba, O Osualale, and Patience Mthunzi-Kufa. "Near infrared femtosecond laser-induced bacterial inactivation." (2019): http://hdl.handle.net/10204/10942Maphanga CP, Manoto SL, Ombinda-Lemboumba S, Osualale O, Mthunzi-Kufa P, Near infrared femtosecond laser-induced bacterial inactivation; SPIE; 2019. http://hdl.handle.net/10204/10942 .TY - Conference Presentation AU - Maphanga, Charles P AU - Manoto, Sello L AU - Ombinda-Lemboumba, Saturnin AU - Osualale, O AU - Mthunzi-Kufa, Patience AB - The use of light to inactivate microbes as an alternative method to the traditional methods of controlling microorganisms continues to draw the attention of researchers. Traditional methods of sterilization and/or pasteurization using chemicals or thermal treatments have certain limitations such as the creation of resistant bacterial strains. The application of pulsed laser irradiation compromises the physiological function of cells, and the degree of destruction is both dose and strain dependent, ranging from reduced cell growth to a complete loss of cell metabolic activity and finally to physical disintegration. This study aimed at using a range of power densities to investigate inactivation of Escherichia coli and Salmonella enteritidis. A Titanium sapphire pulsed laser at 800 nm wavelength, repetition rate of 76 MHz, pulse duration of 120 fs, output power of 560 mW was used in this study. A fluence range was applied on bacterial cultures in a 16 mm diameter petri with a beam spot area of 2.5 cm2 (after expansion). The laser killing effectiveness was evaluated by comparing colony forming units (CFUs) with and without irradiation on 10-7 dilutions of bacterial cultures. Cytotoxicity was analysed using the lactose dehydrogenase (LDH) assay. The laser killing rate varied with bacteria species or strains and the level of fluence. DA - 2019-03 DB - ResearchSpace DP - CSIR KW - Bacteria KW - Colony forming units KW - Escherichia coli KW - Femtosecond KW - Gaussian beam KW - Near infrared KW - Salmonella enteritidis LK - https://researchspace.csir.co.za PY - 2019 T1 - Near infrared femtosecond laser-induced bacterial inactivation TI - Near infrared femtosecond laser-induced bacterial inactivation UR - http://hdl.handle.net/10204/10942 ER -