Sonophore-enhanced nanoemulsions for optoacoustic imaging of cancer

Abstract

Dark Quencher, IRDye QC1 in nanoemulsion form offers excellent optoacoustic performance, suitable for non-invasive pre-clinical optoacoustic imaging.

Tuning Optical Properties of BODIPY Dyes by Pyrrole Conjugation for Photoacoustic Imaging

“…The produced ultrasound waves have low attenuation in tissue, and thus allow for detection at high depths (device dependent, up to 7 cm). [ 11 ] Apart from endogenous contrast (e.g., hemoglobin, melanin), exogenous contrast agents based on noble metal nanoparticles (Au, Ag), [ 12 ] semiconducting nanoparticles, [ 13 ] synthetic melanin, [ 14 ] and small molecule dyes [ 15 ] have been explored. The latter class is particularly promising for clinical diagnostic PAI, as they can be renally cleared, pharmacokinetic properties can considerably be tuned, and they can be used as imaging tags of larger biomolecules without substantially changing their properties.…”

Optoacoustic imaging of GLP-1 Receptor with a near-infrared exendin-4 analog

“…Here, an optoacoustic agent E4x12-Cy7 was successfully synthesized, purified, chemically and optoacoustically characterized and validated in vitro and in vivo. Our rationale behind Cy7 as the absorber of choice for conjugating to neopeptide E4x12 was its high extinction coefficient and broad absorption profile 36 , ideal for optoacoustic detection. The introduction of an optoacoustic tracer, Cy7, to the 12 th position of the amino acid sequence did not perturb its binding affinity to GLP-1R, similar to what we found earlier when substituting at the 14 th position 49 .…”

“…As reported previously 4,24,26 , it can be used without significant reduction of peptide/GLP-1R target binding (~3 nM) 4 . Likewise, we have previously shown that cyanine dyes such as Cy7 exhibit the desired optical characteristics suitable for both optoacoustic and fluorescent imaging 36 . The synthesis of E4x12-Cy7 was achieved in a one-step reaction ( Figure 1B).…”

“…Medical) was used to measure optoacoustic signals. A flow device, fitted into the commercially available MSOT imaging system and containing a soft-tissue mimicking phantom, was prepared as previously described in detail 35,36 . In order to evaluate the optoacoustic performance of E4x12-Cy7, solutions of E4x12-Cy7 in DMSO at concentrations between 2 µM and 25 µM) were prepared.…”

“…Ideally, acoustic signals from the agent would overcome endogenous background signal against the inherently small populations of ß-cells. We have shown in previous studies that a number of near-infrared (NIR) dyes are suitable for optoacoustic imaging 35,36 . Such NIR scaffolds are characteristically high absorbers (typically e > 200, 000 cm -1 M -1 ) with a low quantum yield (θ) of highly packed -conjugated aromatic systems and overlapping p-orbitals of delocalized electrons.…”