Fraunhofer-Gesellschaft

Publica

Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Fluorescence-based in situ assay to probe the viability and growth kinetics of surface-adhering and suspended recombinant bacteria

 
: Avalos Vizcarra, Ima; Emge, Philippe; Miermeister, Philipp; Chabria, Mamta; Konradi, Rupert; Vogel, Viola W.; Möller, Jens

:
Volltext urn:nbn:de:0011-n-3009338 (501 KByte PDF)
MD5 Fingerprint: 1023b96334bcff9c2dd76afec3d6da5f
(CC) by
Erstellt am: 6.12.2016


Biointerphases. Online journal 8 (2013), Nr.1, Art. 22, 9 S.
http://avs.scitation.org/journal/bip
ISSN: 1559-4106
ISSN: 1934-8630
Englisch
Zeitschriftenaufsatz, Elektronische Publikation
Fraunhofer IPA ()
In-Situ-Prüfung; biomedizinische Technik; Biomedizin

Abstract
Bacterial adhesion and biofilm growth can cause severe biomaterial-related infections and failure of medica implants. To assess the antifouling properties of engineered coatings, advanced approaches are needed for in situ monitoring of bacterial viability and growth kinetics as the bacteria colonize a surface. Here, we present an optimized protocol for optical real-time quantification of bacterial viability. To stain living bacteria, we replaced the commonly used fluorescent dye SYTO® 9 with endogenously expressed eGFP, as SYTO® 9 inhibited bacterial growth. With the addition of nontoxic concentrations of propidium iodide (PI) to the culture medium, the fraction of live and dead bacteria could be continuously monitored by fluorescence microscopy as demonstrated here using GFP expressing Escherichia coli as model organism. The viability of bacteria was thereby monitored on untreated and bioactive dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (DMOAC)-coate d glass substrates over several hours. Pre-adsorption of the antimicrobial surfaces with serum proteins, which mimics typical protein adsorption to biomaterial surfaces upon contact with host body fluids, completely blocked the antimicrobial activity of the DMOAC surfaces as we observed the recovery of bacterial growth. Hence, this optimized eGFP/PI viability assay provides a protocol for unperturbed in situ monitoring of bacterial viability and colonization on engineered biomaterial surfaces with single-bacteria sensitivity under physiologically relevant conditions.

: http://publica.fraunhofer.de/dokumente/N-300933.html