Development of a localized surface plasmon resonance platform for Candida albicans antigen identification

Abstract

The incidence of hospital infections caused by the fungus Candida albicans has increased substantially in the past decades. Specific tests for the diagnosis of sepsis due to Candida albicans have high cost and require a long time to obtain results. Given this situation and considering the need for constant search for alternatives in the diagnosis of septicemia by Candida albicans, in this work was developed and evaluated a new sensing platform for an optical immunosensor based on localized surface plasmon resonance. The sensing platform corresponds to a glass slide with nanoparticles of silver adhered on its surface and functionalized with monoclonal anti-candida antibodies of the immunoglobulins class. Cysteine molecules were used as ligand in the antibodies functionalization process and glycine as blockers of non-functionalized sites of the platform. On the preparation of the sensing platform, different concentrations of antibodies were explored. In the evaluation of the platform as a Candida albicans antigens sensor, the identification of different antigen concentrations was demonstrated. The results show the system ability to identify Candida albicans antigen concentrations greater than 50ng/mL, indicating the possibility of the use of the platform as immunosensor for Candida.