Chen Jianmin,Wang Meixia,Ye Yaling,Yang Zhouyan,Ruan Zhipeng,Jin Nan
Microneedle (MN) patch has been used for collecting dermal interstitial fluid (ISF) containing biomarkers from patients with safety, pain-free and easy-to-use manner. However, long sampling time for biomarkers analysis still poses a significant challenge. Here, we describe a new sponge-forming MN patch consisting of polyvinyl formal (PVF) for rapidly extracting ISF from skin. Owing to the supreme water affinity of PVF, this MN patch can extract 1.6 mg ISF in 1 min without the assistance of extra devices, which remarkably facilitates timely analysis. The MN patch had preserved structural integrity in the swelling hydrated state without leaving residues in skin after usage, and the treated skin recovered within 8 h. More importantly, the extracted ISF can be efficiently recovered from the MN patch by simple centrifugation for the subsequent offline analysis of biomarkers such as glucose and cholesterol. Our results reveal that the new sponge-forming MN patch holds considerable promise for minimally invasive sampling ISF for biomarkers detection in real-life situations.
Author: Please verify that the changes made to improve the English still retain your original meaning.Detection of microRNA (miRNA) in dermal interstitial fluid (ISF) has emerged as clinically useful in health status monitoring. However, it remains a great challenge owing to the difficult sampling and low abundance. Here, we report a DNA hydrogel microneedles (MNs) array to realize rapid enrichment and sensitive detection of miRNA in ISF. The MNs’ patch consists of methacrylate hyaluronic acid (MeHA) equipped with a smart DNA circuit hydrogels’ system (MeHA/DNA), in which an appropriate miRNA input enables triggering a cascading toehold-mediated DNA displacement reaction to catalytically cleave cross-linking points to generate amplified fluorescence (FL) for miRNA detection. The MeHA/DNA-MNs patch with high mechanical strength can extract adequate ISF in a short time (0.97 ± 0.2 mg in 5 min) in vivo because of its supreme water affinity. Additionally, the cascading toehold-mediated DNA displacement signal amplification reaction allows for sensitive detection of the low-abundant miRNAs down to 241.56 pM. The DNA hydrogels’ MNs present potential for minimally invasive personalized diagnosis and real-time health monitoring in clinical applications.