Portable hydrogel-based tri-channel fluorescence sensor array for visual detection of multiple explosives

The identification and detection of various types of explosives are essential for human health and environmental monitoring.Array-based sensing approach offers significant advantages in detecting multi-analytes simultaneously,thereby holding great potential in identifying multiple explosives.Here,we report a tri-channel fluorescence array composed of three distinct fluorescence probes based on gold nanoclusters and nicotinamide adenine dinucleotide with well-separated emission colors.Through the specific interactions of explosives with different fluorescent probes and the yielded response patterns,seven explosives can be successfully distinguished with 100%accuracy.In particular,the sensor array exhibits excellent performance in the quantitative analysis of individual explosive and the differentiation of multiple explosive mixtures.To facilitate the field detection towards practical application,the tri-channel fluorescence array was further integrated with polymer hydrogels.The fabricated portable hydrogel-based array sensors can not only visually identify seven different explosives by their distinct fluorescence color change,but also enable quantitative detection based on linear discriminant analysis(LDA)together with a smartphone.This study illustrates the great potential of hydrogel-based fluorescence sensor array as robust sensors for explosives,which also holds significant promise for the development of portable explosive devices towards practical application.

IL-17-triggered downregulation of miR-497 results in high HIF-1α expression and consequent IL-1β and IL-6 production by astrocytes in EAE mice

Interleukin 17(IL-17)is increasingly recognized as a key factor that contributes to the pathogenesis of multiple sclerosis(MS)and its experimental mouse autoimmune encephalomyelitis(EAE)model.However,the roles and regulatory mechanisms of IL-17-induced pro-inflammatory cytokine production in EAE mice remain largely unclear.In this study,the expression of IL-17,hypoxia inducible factor-1α(HIF-1α),IL-1β,IL-6 and microRNA-497(miR-497),as well as their intrinsic associations,was investigated using EAE model mice and cultured astrocytes exposed to IL-17 in vitro.We observed markedly increased production of IL-17,HIF-1α,IL-1βand IL-6 in the brain tissues of EAE mice,while the expression and secretion of HIF-1α,IL-1βand IL-6 were also significantly increased when cultured primary astrocytes from mice were stimulated with IL-17.Meanwhile,the expression of miR-497 was downregulated both in vivo and in vitro.Subsequent in vitro experiments revealed that IL-17 induced the production of IL-1βand IL-6 in astrocytes through the upregulation of HIF-1αas a transcriptional factor,indicating that IL-17-mediated downregulation of miR-497 enhanced HIF-1αexpression.Furthermore,astrocytespecific knockdown of IL-17RA and HIF-1αor astrocyte-specific overexpression of miR-497 by infection with different lentiviral vectors containing an astrocyte-specific promotor markedly decreased IL-1βand IL-6 production in brain tissues and alleviated the pathological changes and score of EAE mice.Collectively,these findings indicate that decreased miR-497 expression is responsible for IL-17-triggered high HIF-1αexpression and consequent IL-1βand IL-6 production by astrocytes in EAE mice.