Article

Multiphoton autofluorescence imaging of intratissue elastic fibers.

Department of Lasermedicine, Fraunhofer Institute of Biomedical Technology, Ensheimer Str. 48, St. Ingbert D-66386, Germany.
Biomaterials (impact factor: 7.4). 03/2005; 26(5):495-500. DOI:10.1016/j.biomaterials.2004.02.059 pp.495-500
Source: PubMed

ABSTRACT Multiphoton induced blue/green autofluorescence by near infrared femtosecond laser pulses has been used to selectively image intratissue elastic fibers in native and tissue engineered (TE) viable heart valves without any invasive tissue removal, embedding, fixation, and staining. Elastic fibers could be clearly distinguished from collagenous structures which emit ultraviolet/violet radiation when excited with intense ultrashort pulses due to second harmonic generation. Deep-tissue three-dimensional imaging of elastic fibers with submicron spatial resolution was performed by optical sectioning of heart valves using a multiphoton laser scanning microscope in connection with a tunable 80 MHz femtosecond laser source. The technology was used to diagnose extracellular matrix structures and cell resettlement of TE heart valves prior implantation. This novel non-invasive method opens the general possibility of high-resolution in situ imaging of elastic fibers, collagen structures and intracellular organelles in living intact tissues without staining.

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Keywords

cell resettlement
 
Deep-tissue three-dimensional imaging
 
elastic fibers
 
emit ultraviolet/violet radiation
 
fixation
 
general possibility
 
high-resolution
 
infrared femtosecond laser pulses
 
intact tissues
 
intracellular organelles
 
invasive tissue removal
 
Multiphoton induced blue/green autofluorescence
 
multiphoton laser scanning microscope
 
novel non-invasive method
 
second harmonic generation
 
selectively image intratissue elastic fibers
 
situ imaging
 
submicron spatial resolution
 
TE heart valves prior implantation
 
tunable 80 MHz femtosecond laser source