## 6 Conclusions  
We demonstrate the potential feasibility of a novel concept for highly reliable, natural delivery of H\({}^{+}\) and O\({}_{2}\) into tissues. The tissue-adhesive HOGP has stable storage properties and is easy to fabricate and handle. Furthermore, we confirmed that cutaneous uptake of moisture-induced H\({}^{+}\) and O\({}_{2}\) produced by the HOGP significantly altered the circulating levels of H\({}^{+}\) and O\({}_{2}\) in a small animal model. Conceptualization, S.H.-H.Y. and W.-T.H., Investigation, T.-H.Y., W.-H.C., B.-Y.W. and Y.-Y.K., Writing and editing, S.H.-H.Y., Funding Acquisition, W.-T.H., M.-H.L., and S.H.-H.Y. All authors have read and agreed to the published version of the manuscript. Funding for this study was provided by TO2M corporation and The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE) of Taiwan. Institutional Review Board StatementAll animal handling procedures were approved by National Defense Medical Center (IAUIC No 1091203) and this animal study was performed according to the Guidelines for Animal Experimentation of National Defense Medical Center. Informed Consent StatementNot applicable. Data Availability StatementThe datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request. AcknowledgmentsWe thank the Molecular Imaging Facility Small Animal 7T PET/MR and Brain Research Center at National Yang Ming Chaio Tung University for technical support. ConflictsThe authors declare no conflict of interest. References  
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