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We show that catalyst-free aqueous solutions of hyperpolarized [1- 13 C]succinate can be produced using parahydrogen-induced polarization (PHIP) and a combination of homogeneous and heterogeneous catalytic hydrogenation reactions. We generate hyperpolarized [1- 13 C]fumarate via PHIP using para-enriched hydrogen gas with a homogeneous ruthenium catalyst, and subsequently remove the toxic catalyst and reaction side products via a purification procedure. Following this, we perform a second hydrogenation reaction using normal hydrogen gas to convert the fumarate into succinate using a solid Pd/Al 2 O 3 catalyst. This inexpensive polarization protocol has a turnover time of a few minutes, and represents a major advance for in vivo applications of [1- 13 C]succinate as a hyperpolarized contrast agent.

15 N spin-lattice relaxation dynamics in metronidazole- 15 N 3 and metronidazole- 15 N 2 isotopologues are studied for rational design of 15 N-enriched biomolecules for signal amplification by reversible exchange in microtesla fields. 15 N relaxation dynamics mapping reveals the deleterious effects of interactions with the polarization transfer catalyst and a quadrupolar 14 N nucleus within the spin-relayed 15 N- 15 N network.

Substantial (31)P NMR signal enhancement of more than two orders of magnitude at 7 T for free and bound PPh3 species was observed under reversible interaction of (PPh3)3Ir(H2)Cl with parahydrogen. The large improvement in sensitivity made single-shot (31)P NMR imaging of a model object possible. The observed effects are temperature and magnetic field dependent as shown experimentally and theoretically.

The results show that, in general, observation of PHIP effects on metals does not require the presence of a support. In addition, certain metal oxides can produce PHIP effects in the absence of a supported metal. The new promising catalysts for producing PHIP heterogeneously have been identified.

Spatially resolved NMR is employed to quantitatively map the temperature of a solid catalyst under operating conditions during H(2) oxidation with O(2) over Pt/γ-Al(2)O(3). As this new non-invasive in situ technique utilizes the (27)Al NMR signal of the solid phase, it is suitable for catalyst temperature mapping in both liquid- and gas-phase heterogeneous catalytic processes.

Parahydrogen-induced polarization was observed in the gas phase heterogeneous hydrogenation of propyne catalyzed by Pd(0) nanoparticles embedded in an ionic liquid phase supported on activated carbon fibers (Pd(0)/SILP/ACF). The results were markedly different from those obtained with a reference catalyst, Pd(0)/ACF, demonstrating the important role of the ionic liquid.