Diagnosis facilitates the discovery of an impending disease. A complete and accurate treatment of cancer depends heavily on its early medical diagnosis. Cancer, one of the most fatal diseases world-wide, consistently affects a larger number of patients each year. Magnetism, a physical property arising from the motion of electrical charges, which causes attraction and repulsion between objects and does not involve radiation, has been under intense investigation for several years. Magnetic materials show great promise in the application of image contrast enhancement to accurately image and diagnose cancer. Chelating gadolinium (Gd Ⅲ) and magnetic nanoparticles (MNPs) have the prospect to pave the way for diagnosis, operative management, and adjuvant therapy of different kinds of cancers. The potential of MNP-based magnetic resonance (MR) contrast agents (CAs) now makes it possible to image portions of a tumor in parts of the body that would be unclear with the conventional magnetic resonance imaging (MRI). Multiple functionalities like variety of targeting ligands and image contrast enhancement have recently been added to the MNPs. Keeping aside the additional complexities in synthetic steps, costs, more convoluted behavior, and effects in-vivo, multifunctional MNPs still face great regulatory hurdles before clinical availability for cancer patients. The trade-off between additional functionality and complexity is a subject of ongoing debate. The recent progress regarding the types, design, synthesis, morphology, characterization, modification, and the in-vivo and in-vitro uses of different MRI contrast agents, including MNPs, to diagnose cancer will be the focus of this review. As our knowledge of MNPs' characteristics and applications expands, their role in the future management of cancer patients will become very important. Current hurdles are also discussed, along with future prospects of MNPs as the savior of cancer victims.
Detailed studies of the structures, magnetic properties and photodimerization of a series of formato-bridged MOFs with the general formula M2(HCOO)3(4,4′-bpe)3(H2O)3(X) (4,4′-bpe = 4,4′-bipyridylethylene, M = Mn (1-X-), X- = ClO4-, NO3-, BF4-, I-, Br-; M = Co (2-X-), X- = ClO4-, NO-3; M = Zn (3-X-), X- = NO3-) were reported. Careful magnetic measurements on an ori- ented single crystal of 1-ClO4- determined the spin-flop magnetic phase diagram and some intrinsic parameters, such as the intralayer coupling J, the anisotropy field HA and the exchange field HE. Different anions can remarkably tune the magnetic properties of 1-X-, especially the critical fields of the spin-flop transition. Compound 2-ClO4- remained paramagnetic down to 2 K.
Rare-earth-based permanent magnets are one of the most important magnets in both scientific and industrial fields. With the development of technology, nanostructured rare-earth-based permanent magnets with high energy products are highly required. In this article, we will review the progress in chemical synthetic strategies of nanostructured rare-earth-based permanent magnets.
A multifunctional material with both electrorheological(ER) performance and luminescence property was synthesized by a simple coprecipitation. The tetrabutyl titanate, as well as the Tb(NO3)3·6H2O and sulphosalicylic acid(C7H6O6S·2H2O, SSA) were chosen as starting materials. The composition, ER performance and luminescence property of the material were studied. The results showed that a novel material(TiTbSSA) with both ER performance and luminescence property was obtained. The relative shear stress τr(τr=τE/τ0, τE and τ0 were the shear stresses of the suspension with and without an applied electric field) of the suspension(30 wt.%) of the material in silicone oil reached 32.7 at a shear rate of 12.5 s–1 and an electric field strength of 4 kV/mm(DC electric field). The material containing the rare earth(RE=Tb) complex exhibited fine luminescence performance and higher ER activity. Therefore, it is a novel multifunction material which would have wide application prospect.
Nanoparticles(NPs) with easily modified surfaces have been playing an important role in biomedicine.As cancer is one of the major causes of death,tremendous efforts have been devoted to advance the methods of cancer diagnosis and therapy.Recently,magnetic nanoparticles(MNPs) that are responsive to a magnetic field have shown great promise in cancer therapy.Compared with traditional cancer therapy,magnetic field triggered therapeutic approaches can treat cancer in an unconventional but more effective and safer way.In this review,we will discuss the recent progress in cancer therapies based on MNPs,mainly including magnetic hyperthermia,magnetic specific targeting,magnetically controlled drug delivery,magnetofection,and magnetic switches for controlling cell fate.Some recently developed strategies such as magnetic resonance imaging(MRI) monitoring cancer therapy and magnetic tissue engineering are also addressed.
Colloidal chemical synthesis of various types of magnetic nanocrystals is discussed with regard to recent discoveries.We first outline the chemical preparation of single-component magnetic nanocrystals with controlled size,shape,and uniformity based on several solution-phase methods,especially thermal decomposition and/or reduction method.Then we discuss the synthetic strategies of multi-component nanocrystals incorporating at least one magnetic component by manipulating heterogeneous nucleation and growth process.Toward the end,approaches for preparing hollow/porous magnetic nanocrystals are highlighted.We believe that the summarized chemical synthesis will pave the way for the future development of extraordinary magnetic nanocrystals.
