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Breast cancer (BC) is a major global health problem, with ≈20-25% of patients overexpressing human epidermal growth factor receptor 2 (HER2), an aggressive marker, yet access to early detection and treatment varies across countries. A low-cost, equipment-free, and easy-to-use polydiacetylene (PDA)-based colorimetric sensor is developed for HER2-overexpressing cancer detection, designed for use in low- and middle-income countries (LMICs). PDA nanoparticles are first prepared through thin-film hydration. Subsequently, hydrophilic magnetic nanoparticles and HER2 antibodies are sequentially conjugated to them. The synthesized HER2-MPDA can be concentrated and separated by a magnetic field while inheriting the optical characteristics of PDA. The specific binding of HER2 antibody in HER2-MPDA to HER2 receptor in HER2-overexpressing exosomes causes a blue-to-red color change by altering the molecular structure of the PDA backbone. This colorimetric sensor can simultaneously separate and detect HER2-overexpressing exosomes. HER2-MPDA can detect HER2-overexpressing exosomes in the culture medium of HER2-overexpressing BC cells and in mouse urine samples from a HER2-overexpressing BC mouse model. It can selectively isolate and detect only HER2-overexpressing exosomes through magnetic separation, and its detection limit is found to be 8.5 × 10 8  particles mL -1 . This colorimetric sensor can be used for point-of-care diagnosis of HER2-overexpressing BC in LMICs., (© 2023 Wiley‐VCH GmbH.)

An understanding of neovascularization and/or angiogenesis in cancer is acutely required for effective cancer therapy due to concerns about tumor growth and metastasis. In particular, integrin αvβ3 is closely associated with cell migration and invasion during angiogenesis. Hence, we developed aptamer(αvβ3)-conjugated magnetic nanoparticles (Apt(αvβ3)-MNPs) to enable precise detection of integrin-expressing cancer cells using magnetic resonance imaging. Apt(αvβ3)-MNPs exhibited not only cytocompatibility, but also an efficient targeting ability with high magnetic sensitivity through in vitro/in vivo studies. The results of this study demonstrate that Apt(αvβ3)-MNPs have the potential to be used for accurate tumor diagnosis and therapy., (Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.)

Cancer cells can express specific biomarkers, such as cell membrane proteins and signaling factors. Thus, finding biomarkers and delivering diagnostic agents are important in the diagnosis of cancer. In this study, we investigated a biomarker imaging agent for the diagnosis of hepatic cancers. The asialoglycoprotein receptor (ASGPr) was selected as a biomarker for hepatoma cells and the ASGPr-targetable imaging agent bearing a galactosyl group was prepared using manganese ferrite nanoparticles (MFNP) and galactosylgluconic acid. The utility of the ASGPr-targetable imaging agent, galactosylated MFNP (G-MFNP) was assessed by several methods in ASGPr-expressing HepG2 cells as target cells and ASGPr-deficient MCF7 cells. Physical and chemical properties of G-MFNP were examined using Fourier-transform infrared spectroscopy, dynamic light scattering, zeta potential analysis, and transmission electron microscopy. No significant cytotoxicity was observed in either cell line. Targeting ability was assessed using flow cytometry, magnetic resonance imaging, inductively coupled plasma atomic emission spectroscopy, absorbance analysis, dark-field microscopy, Prussian blue staining, and transmission electron microscopy. We demonstrated that G-MFNP target successfully and bind to ASGPr-expressing HepG2 cells specifically. We suggest that these results will be useful in strategies for cancer diagnoses based on magnetic resonance imaging.

We have developed a nanovector consisting of hyaluronic acid (HA) and poly-L-lysine-graft-imidazole (PLI)-based polyplexes containing Bcl-xL-specific shRNA-encoding plasmid DNA (HA/PLI/pDNA) for CD44 targeted gastric cancer therapy. The prepared ternary polyplexes have a negative surface charge of -24 mV and a size of approximately 100 nm at an N/P ratio of 5 with HA/PLI molar ratio of 0.03. Gel electrophoresis and cell viability experiments demonstrated that the ternary polyplexes showed high stability and no cytotoxicity due to the anchored HA molecules on the surface of PLI/pDNA binary polyplexes. Selective cancer cell death was achieved by CD44-mediated gene delivery and the internalized gene was effectively escaped from endosomes due to the buffering capacity of imidazole groups in an acidic environment. These nanovectors may be highly efficient gene delivery tools that allow the selective destruction of metastatic gastric cancer cells., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

We fabricated hyaluronan-modified magnetic nanoclusters (HA-MNCs) for detection of CD44-overexpressing breast cancer using magnetic resonance (MR) imaging. CD44 is closely associated with cancer growth, including proliferation, metastasis, invasion, and angiogenesis. Hence, pyrenyl hyaluronan (Py-HA) conjugates were synthesized as CD44-targetable surfactants with hyaluronan (HA) and 1-pyrenylbutyric acid (Py) to modify hyaluronan on hydrophobic magnetic nanocrystals. Subsequently, HA-MNCs were fabricated using the nano-emulsion method; magnetic nanocrystals were simultaneously self-assembled with Py-HA conjugates, and their physical and magnetic properties depended on the degree of substitution (DS) of Py in Py-HA conjugates. HA-MNCs exhibited superior targeting efficiency with MR sensitivity as well as excellent biocompatibility through in vitro/in vivo studies. This suggests that HA-MNCs can be a potent cancer specific molecular imaging agent via targeted detection of CD44 with MR imaging., (Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.)

The synchronization of gene expression and cell trafficking in transfected stem cells is crucial for augmentation of stem cell functions (differentiation and neurotropic factor secretion) and real time in vivo monitoring. We report a magnetic nanoparticle-based gene delivery system that can ensure simultaneous gene delivery and in vivo cell trafficking by high resolution MR imaging. The polar aprotic solvent soluble MnFe₂O₄ nanoparticles were enveloped using cationic polymers (branched polyethyleneimine, PEI) by the solvent shifting method for a gene loading. Using our magnetic nanovector system (PEI-coated MnFe₂O₄ nanoparticles), thus, we synchronized stem cell migration and its gene expression in a rat stroke model., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

We report a simple and scalable method for the separation of semiconducting single-walled carbon nanotubes (SWNTs) from metallic SWNTs using magnetic nanoparticles (MNPs) functionalized with polycationic tri-aminated polysorbate 80 (TP80). MNPs-TP80 are selectively adsorbed on acid-treated semiconducting SWNTs, which makes the semiconducting SWNTs be highly concentrated to over 95% under a magnetic field. Almost all the field effect transistor network devices, which were fabricated using separated semiconducting SWNTs, exhibited a p-type semiconducting behavior with an on/off ratio of higher than 10(4).

We fabricated multimode nanoprobes for acquisition of biological information at different object levels, i.e., in vivo detection and ex vivo validation for characterizing tumor angiogenesis. Fluorescent magnetic nanoprobes (FMNPs) were synthesized by using amphiphilic pyrenyl polyethylene glycol (Py-PEG) and superparamagnetic MnFe(2)O(4) nanocrystals (MNCs). Py-PEG, which is synthesized by conjugation of hydrophilic PEG with hydrophobic and fluorescent 1-pyrenebutyric acid through an esterification process, is capable of self-assembly and maintaining a high UV fluorescent intensity in aqueous phase. Py-PEG can be used as a fluorescent surfactant that simultaneously and efficiently encapsulates MNCs to exhibit fluorescent and magnetic properties as well as maintaining high water-solubility. Consequently, we proved that our biologically non-toxic FMNPs were prominent multimode imaging probes by showing not only excellent MR sensitivity but also high illumination intensity with strong signal strength under short exposure time of UV light from the extensive imaging studies of in vitro/vivo and ex vivo using orthotopic and xenograft mice models., (Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.)

Novel bifunctional fluorescent magneto polymeric nanoprobes (FMPNs) were synthesized to provide simultaneous diagnostic information via magnetic resonance imaging (MRI) and optical imaging. FMPNs consist of ultra-sensitive magnetic nanocrystals that function as MR probes combined with Nile Red, which functions as a fluorescent probe. FMPNs were encapsulated by a nano-emulsion method in polyvinyl alcohol (PVA, 87-89% hydrolyzed) through a matrix of polymethyl methacrylate (PMMA). FMPNs exhibited excellent colloidal stability and monodispersity. The production of MR and optical images demonstrated that FMPNs have potential as dual-mode imaging agents.

Cetuximab conjugated fluorescent magnetic nanohybrids (CET-FMNHs) were synthesized for detection of human epithelial cancer via magnetic resonance (MR) and optical imaging. Spherical FMNHs consist of MnFe(2)O(4) magnetic nanocrystals encapsulated in pyrene-labeled PCL-b-PMAA as a surfactant prepared by a nano-emulsion method. FMNHs demonstrated excellent colloidal stability and biocompatibility for biomedical application. Antibody conjugated fluorescent magnetic nanohybrids (CET-FMNHs) served as effective agents for both magnetic resonance (MR) and fluorescence optical imaging of cancer cell lines.