Early-Stage Imaging of Nanocarrier-Enhanced Chemotherapy Response in Living Subjects by Scalable Photoacoustic Microscopy

Abstract

Conventional evaluation methods of chemotherapeutic efficacy such as tissue biopsy and anatomical measurement are either invasive with potential complications or dilatory to capture the rapid pathological changes. Here, a sensitive and resolution-scalable photoacoustic microscopy (PAM) with theranostic nanoformulation was developed to noninvasively monitor the therapy response in a timely manner. Ultrasmall graphene oxide nanosheets were designed as both drug-loading vehicle and photoacoustic signal amplifier to the tumor. With the signal enhancement by the injected contrast agents, the subtle microvascular changes of the chemotherapy response in tumor were advantagely revealed by our PAM system, which was much earlier than the morphological measurement by standard imaging techniques. High tumor uptake of the enhanced nanodrug with Cy5.5 labeling was validated by fluorescence imaging. At different observation scales, PAM offered unprecedented sensitivity of optical absorption and high spatial resolution over optical imaging. Our studies demonstrate the PAM system with synergistic theranostic strategy to be a multiplexing platform for tumor diagnosis, drug delivery, and chemotherapy response monitoring at a very early stage and in an effective way.

Indocyanine green loaded graphene oxide for high-efficient photoacoustic tumor therapy

“…1,4 In photoacoustic therapy, photoacoustic probes (or agents) are exposed to a pulsed laser, the light energy absorbed by photoacoustic probes can be converted into acoustic energy based on photoacoustic e®ect. [5][6][7][8][9][10][11][12][13][14] Then, the magnitude of photoacoustic amplitude can generate a strong shock wave, with peak pressure of 100 Mpa. 15 Such a strong shock wave can destroy the cell membrane, resulting in cell apoptosis.…”

Recent Advances in Photoacoustic Imaging for Deep-Tissue Biomedical Applications

“…Besides tumor imaging, PAI also can be used to evaluate the therapeutic efficacy of chemotherapy, photodynamic therapy, radiation therapy and antiangiogenic therapy 103-106. For example, Hasan et al used PAI to monitor the progress of photodynamic therapy (PDT) 104.…”

Graphene-based nanomaterials for bioimaging

“…Likewise, a number of drugs (doxorubicin (DOX) (41), camptothecin (CPT) (42), etc . ), photosensitizers (PSs) (chlorin e6 (Ce6) (17), sinoporphyrin sodium (DVDMS) (43), etc.)…”