Abstract:
:Achieving label-free, molecular-specific imaging with high spatial resolution in deep tissue is often considered the grand challenge of optical imaging. To accomplish this goal, significant optical scattering in tissues has to be overcome while achieving molecular specificity without resorting to extrinsic labeling. We demonstrate the feasibility of developing such an optical imaging modality by combining the molecularly specific stimulated Raman excitation with the photoacoustic detection. By employing two ultrashort excitation laser pulses, separated in frequency by the vibrational frequency of a targeted molecule, only the specific vibrational level of the target molecules in the illuminated tissue volume is excited. This targeted optical absorption generates ultrasonic waves (referred to as stimulated Raman photoacoustic waves) which are detected using a traditional ultrasonic transducer to form an image following the design of the established photoacoustic microscopy.
journal_name
Proc Natl Acad Sci U S Aauthors
Yakovlev VV,Zhang HF,Noojin GD,Denton ML,Thomas RJ,Scully MOdoi
10.1073/pnas.1012432107subject
Has Abstractpub_date
2010-11-23 00:00:00pages
20335-9issue
47eissn
0027-8424issn
1091-6490pii
1012432107journal_volume
107pub_type
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