Intrinsically Copper‐64‐Labeled Organic Nanoparticles as Radiotracers

Abstract

PET friendly: labels for PET imaging are incorporated into completely organic porphysomes by using a fast (30 min), one-pot, high-yielding (>95 %) procedure to produce highly stable (>48 h) radiolabeled nanoparticles that show the highest specific activity ever reported for a (64) Cu-labeled nanoparticle. These (64) Cu-porphysomes can be accurately and noninvasively tracked in vivo.

Molecular Interactions in Organic Nanoparticles for Phototheranostic Applications

“…134,135 Measurement of serum half-life by scintillation counting indicates that porphysomes possess a blood clearance half-life of 1.23 h (first phase) and 11.1 h (second phase). 134 No acute toxicity has been reported for porphysomes in preliminary studies. Mice treated with 1000 mg kg −1 showed no behavioral changes nor weight loss.…”

In situ conversion of porphyrin microbubbles to nanoparticles for multimodality imaging

“…They have been used as fluorescence imaging 21 , positron emission tomography 22,23 , magnetic resonance imaging 24 and photoacoustic imaging 21,25 contrast agents, as well as for photodynamic therapy (PDT) 26 and photothermal therapy (PTT) 27 . As with the majority of nanoparticles intended for tumour targeting, the delivery of these porphyrin-based nanoparticles relies on the enhanced permeability and retention (EPR) effect, requiring on the order of hours to days for maximum accumulation.…”

“…a, pMBs and pNPs embedded in an acrylamide gel phantom were imaged using ultrasound(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24) MHz transducer in contrast mode), photoacoustic (824 nm, 21 MHz transducer) and fluorescence (green excitation, 503 nm-548 nm; 560 nm long-pass detection) imaging. Samples: (1) phosphate buffered saline (PBS), (2) pMBs without applying ultrasound pulses (zero pulses), and after applying (3) one pulse, (4) three pulses and (5) ten pulses.…”

Recent advances in the development of organic photothermal nano-agents

“…Furthermore, metal ions can be introduced into these porphysomes owing to the intrinsic metal chelating property of the porphyrin ring. For example, 64 Cu, a radioisotope, can be simply inserted into porphysomes for positron emission tomography (PET) [60]. In addition, manganese ions can also be incorporated directly into the building blocks of porphysome nanoparticles to enable T1 contrast in magnetic resonance (MR) imaging [61] Porphysomes self-assembled from simple monomers are enzymatically biodegradable and highly biocompatible.…”