Metabolic magnetic resonance imaging (MRI) using hyperpolarized (HP) pyruvate is becoming a non‐invasive technique for diagnosing, staging, and monitoring response to treatment in cancer and other diseases. The clinically established method for producing HP pyruvate, dissolution dynamic nuclear polarization, however, is rather complex and slow. Signal Amplification By Reversible Exchange (SABRE) is an ultra‐fast and low‐cost method based on fast chemical exchange. Here, for the first time, we demonstrate not only in vivo utility, but also metabolic MRI with SABRE. We present a novel routine to produce aqueous HP [1‐13C]pyruvate‐d3 for injection in 6 minutes. The injected solution was sterile, non‐toxic, pH neutral and contained ≈30 mM [1‐13C]pyruvate‐d3 polarized to ≈11 % (residual 250 mM methanol and 20 μM catalyst). It was obtained by rapid solvent evaporation and metal filtering, which we detail in this manuscript. This achievement makes HP pyruvate MRI available to a wide biomedical community for fast metabolic imaging of living organisms.

A new method is described for the determination of the pesticide λ-cyhalothrin (LC). It combines SERS detection with molecular imprinting and largely improves selectivity. A multilayer surface imprinted nanocomposite was synthesized in two steps on a nanostructure of type SiO@rGO@Ag acting as a substrates. Firstly, the surface of the SiO@rGO@Ag composite was modified with self-polymerized dopamine. Secondly, surface-initiated polymerization was carried out to prepare a molecularly imprinted polymer (MIP) using LC as the template. The use of this SiO@rGO@Ag-MIP allows for excellent SERS based detection and has high selectivity for LC. The Raman intensity and LC concentration present perfect linear relationship between 10 to 10 mol L and the detection limit is 3.8×10 mol L. All the procedures are conducted in aqueous or ethanol solution. Graphical abstract Schematic of a new method for determination of the pesticide λ-cyhalothrin. It combines SERS detection with molecular imprinting and largely improves selectivity. A multilayer surface imprinted nanocomposite was synthesized in two steps on a nanostructure of type SiO@rGO@Ag acting as a substrates.

Novel molecularly imprinted polymers (MIPs) based on the technique of surface-enhanced Raman scattering (SERS) were successfully prepared. Firstly, ZnO nanorods were fabricated with Ag by reduction of Ag on the surface of the ZnO nanorods. Then, ZnO/Ag heterostructures were used as the substrate, rhodamine 6G was used as the template molecule, acrylamide was used as the functional monomer, ethylene glycol dimethacrylate was used as the cross-linker, and 2,2'-azobis(2-methylpropionitrile) was used as the initiator to prepare the ZnO/Ag MIPs (ZOA-MIPs). Through characterization analysis, it was proved that the novel ZOA-MIPs exhibited excellent SERS properties and selectivity. Under the optimal conditions, there was a good linear relationship (R = 0.996) between the Raman signal (at 1654 cm) and the concentration of the templates, and the detection limit was 10 mol L. It was also proved that the ZOA-MIPs had the property of self-cleaning, resulting in good reusability. It is envisaged that the sensitivity of SERS coupled with the selectivity of MIPs could result in a promising chemosensor for practical applications.

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In this study, a novel SERS sensor was successfully prepared by combining a molecular imprinted technique (MIT) with a SERS technique to improve the selectivity of the traditional SERS technique. Moreover, a thermo-sensitive technique was also introduced to confer stimuli-responsive properties to the materials. In a typical procedure, the Ag nanoparticles (NPs) were reduced on the surface of ZnO nanorods (NRs), and the ZnO/Ag heterostructures were used as the SERS substrates. Subsequently, a layer of thermo-sensitive imprinted polymer was coated on the surface of ZnO/Ag heterostructures to prepare the thermoresponsive ZnO/Ag/molecularly imprinted polymers (ZOA-TMIPs) by precipitation polymerization. Moreover, it was proven that the ZOA-TMIPs were regenerable and exhibited good reusability. The results proved that the materials in this study can be effectively used for residual organic dye detection in water.

Ag-MIPs were prepared through a multistep procedure, in which MPS and LC were selected as the template molecules. These materials could selectively rebind the templates and could be detected using Raman spectroscopy.

A novel magnetic molecularly imprinted sensor (Fe 3 O 4 /GO/Ag-MIPs) was successfully synthesized. Combining with the technique of surface-enhanced Raman scattering (SERS), it could be applied to detect cyfluthrin (LC). Herein, GO and Ag particles were anchored on the surface of the Fe 3 O 4 @SiO 2 to obtain the composite (Fe 3 O 4 /GO/Ag), which was prepared as a SERS substrate. Then, the Fe 3 O 4 /GO/Ag-MIPs (FGA-MIPs) prepared by precipitation polymerization was evaluated as the SERS imprinted sensor for selective detection of LC from aqueous medium. The morphology and structural properties of FGA-MIPs were characterized by a series of modern analysis measurements. The results proved that FGA-MIPs possessed wonderful magnetic separation, sensitive SERS detection, and selectivity. Under optimal conditions, it exhibited a good linear relationship (R 2 = 0.9926) between the Raman shift (at 1,004 cm −1 ) and the concentration of LC among 10 −3 -10 −8 mol/L, and the limit of detection was 10 −8 mol/L. Meanwhile, the selective experiment indicated that this material owned specific selectivity to the template molecules. Thus, the result of this experiment demonstrated that the FGA-MIPs was a highly sensitive and selective sensor material in the field of LC detection, and it provided a new approach to other residual pyrethroid detection in the environment water.

In this study, a novel detection method based on the technique of surface enhanced Raman scattering (SERS) was presented. Firstly, the homogeneous Ag particles were prepared and CdTe quantum dots were modified on the surface of Ag particles to synthesize the Ag/CdTe heterostructures as the SERS substrate. Then 2,6‐DCP was chosen as the template molecule and combined the technique of atom transfer radical polymerization to prepare Ag/CdTe/molecular imprinted polymers (MIPs). Through characterization analysis, it was proved that the Ag/CdTe/MIPs exhibited splendid SERS properties and selectivity. Under the optimal condition, it was presented good linear relationship (R2 = 0.96) between the Raman signal (at 1596 cm−1) and the concentration of the templates, and the detection limit was determined as 10−9 mol L−1. It was envisaged that the sensitivity of SERS coupled with the selective properties of MIPs could induce a promising chemosensor for practical applications.