An extraction free modified o-phthalaldehyde assay for quantifying residual protein and microbial biofilms on surfaces. Issue 8 (14th September 2018)

• Record Type: Journal Article
• Authors: Guan, Allan; Wang, Yi; Phillips, K. Scott
• Is Part Of: Biofouling. Volume 34:Issue 8(2018)
• Page Start: 925
• Page End: 934
• Publication Date: 2018-09-14
• Subjects: Endoscope -- biofilm -- protein -- extraction -- reprocessing -- detection; Marine fouling organisms -- Periodicals; Materials -- Biodeterioration -- Periodicals; Fouling -- Periodicals; Biodegradation -- Periodicals; Environmental Microbiology -- Periodicals; Water Microbiology -- Periodicals; 576.165
• DOI: 10.1080/08927014.2018.1521959
• Languages: English
• ISSNs: 0892-7014

Abstract

Abstract: Biological contamination of surfaces in industry and healthcare is an important vector of disease transmission. Current assays for detecting surface-adherent contamination require extraction of biological soil. However, physical inaccessibility or poor solubility may limit recovery. Here, how the o-phthalaldehyde (OPA) protein assay can be modified to measure residual protein (modeled with bovine serum albumin) or biofilm on a surface without extraction is described. The assay limit of detection (LOD) for protein was 1.6 µg cm −2 . The detection threshold for Staphylococcus epidermis biofilm was 117 µg cm −2 . The clinical utility of the method was demonstrated for measurements taken from clinically used endoscopes. Since this method is more sensitive than extraction-based testing, clinical results should not be compared with conventional benchmarks. By enabling direct detection and quantification of soils in complex or hard-to-reach areas, this method has potential to improve the margin of safety in medical and industrial cleaning processes.