Abstract
Abnormal sweating is closely associated with the occurrence and progression of various serious diseases, yet quantitatively and accurately assessing sweat pore function remains challenging. In this study, a crystalline covalent organic framework (COF) paper was developed for precise sweat pore analysis of sweating disorders. The delicately designed COF system achieved high-contrast sweat-responsive color change through the doping of sweat contents while showing no response to water, greatly enhancing resistance to environmental humidity interference. The flexible COF paper, grown in situ on PVDF paper substrates, adapts well to various skin surfaces, successfully recording the distribution and activity information on sweat pores through the "sweat pore mapping" technique of absorbing picoliter sweat within only 2 min of contact. Using the COF paper to obtain naked eye visible active sweat pore image can be used for accurate analysis of sweat pore function. Preliminary clinical studies using the COF paper have shown their ability in early disease warning and their potential in auxiliary diagnosis for sweating disorders. Furthermore, the COF paper demonstrated potential in monitoring the efficacy of topical treatments for skin diseases, providing a valuable tool for prognosis tracking. This study showcases the effective utilization of the COF paper for sweat pore analysis, underscoring the significant potential of COFs for advancing precision clinical research.