In fact, blood has been combined with ex situ p-H2 hyperpolarized analytes before, but its own contents have not been studied by nh-PHIP previously. However, achieving compatibility of nh-PHIP with blood is much more challenging than for urine. Method development will have to overcome challenges related to the complex nature of the blood matrix i.e. its cellular fraction, high protein content, large alcohol insoluble fraction, as methanol is the optimal solvent for nh-PHIP. Scheme 1. Para-hydrogen (pH2) nh-PHIP active transient complex consisting of an iridium metal-based catalyst (Ir-IMes) with 1-methyl-1,2,3-triazol (mtz) co-substrate. The complex is in equilibrium with the analytes (i.e. various N-heterocycles) in the biofluid mixture and needs mostly methanol medium for optimal performance. The hydrides HA (trans to analyte) and HX (trans to co-substrate) are detected in 1D This study focuses on adapting nh-PHIP for the detection of adenine phosphonucleotides (ATP, ADP, AMP), the central compounds of energy metabolism. We show how pH2 hyperpolarization can be used for sensitivity-enhanced NMR analysis of ATP, ADP, AMP and nicotinamide in blood. Detection of ATP would be diagnostic value because as ATP release from cells regulates immune responses and several physiological functions . Elevated ATP levels can indicate infections and pathological conditions that affect the immune responses, such as cancer, inflammatory disorders, ischemia, trauma and infections. Therefore, quantitative measurement of plasma ATP levels is important for diagnosis and monitoring of disease progression. in the SI) and used without further purification. Iridium catalyst complex precursor [Ir(Cl)(COD)(IMes)] was prepared according to published procedures. Cosubstrate 1-methyl-1,2,3-triazole (mtz) was synthesized as previously described. All analyte solutions were prepared gravimetrically and NMR samples were prepared volumetrically.