In situ measurement of superoxide and hydroxyl radicals by frequency mixing detection technique

In vivo Preclinical Tumor-Specific Imaging of Superparamagnetic Iron Oxide Nanoparticles Using Magnetic Particle Imaging for Cancer Diagnosis

Purpose

Magnetic particle imaging (MPI) is an emerging radiation-free, non-invasive three-dimensional tomographic technology that can visualize the concentrations of superparamagnetic iron oxide nanoparticles (SPIONs). To verify the applicability of the previously proposed point-of-care testing MPI (PoCT-MPI) in medical diagnosis and therapeutics, we imaged SPIONs in animal tumor models.

Methods

CT26 or MC38 mouse colon carcinoma cells (2 × 10⁶ cells) were subcutaneously injected into the right flank of BALB/c mice. SPIONs were either injected directly into the tumor lesions in the intratumoral group or through tail veins in the intravenous group. CT26 and MC38 tumor models were examined both intratumorally and intravenously to confirm the biological availability of SPIONs using PoCT-MPI.

Results

Signals were observed in the tumor lesions from day 1 to day 7. This is the first study to successfully image the pathological region and show the biodistribution of SPIONs in CT26 tumor models using the recently developed PoCT-MPI technology. Furthermore, MC38 tumor models were examined, resulting in similar images to those of the CT26 tumor model in both intratumoral and intravenous groups.

Conclusion

The present study demonstrates the biological applicability of PoCT-MPI, which promises to be a powerful diagnostic and therapeutic technique in biomedical imaging.

A mitochondrion targeting fluorescent probe for imaging of intracellular superoxide radicals

A fluorogenic probe with mitochondria targeting capability was prepared for detection of superoxide radical generation inside mitochondria in living cells.