Human PPY blocking peptide

With the rapid development of flexible and wearable electronic devices, research on high-sensitivity strain sensors has been attracting much attention. Here, glutaraldehyde is used as a cross-linking reagent to precross-link poly(vinyl alcohol); then FeCl3 center dot 6H(2)O is added into the precross-linked poly(vinyl alcohol) to obtain composite films of FeCl3@PVA after gelatinization and freeze drying. Elastic conductive films of polypyrrole@poly(vinyl alcohol) (PPy@PVA) are prepared by immersing FeCl3@PVA into a solution of pyrrole in acetonitrile and water to complete the polymerization in situ. The effects of the concentrations of glutaraldehyde and FeCl3 center dot 6H(2)O on the films structure and properties have been studied in detail; the results show that the strain sensor prepared from the optimized film has excellent stretchability (strain up to 309.5%), mechanical property (tensile strength of 32.8 MPa), and relatively high sensitivity (gauge factor can reach 5.07 under 1.0% strain). It can be used to detect various tiny physiological signals, for example, detecting the number of pulse beats, bending of the knuckles at different frequencies, and recognizing the pronunciation of different words by vocal cord vibration. These good properties mean that this kind of PPy@PVA strain sensor has great application prospects in physiological monitoring.

With a 2-phenylpyridine(ppy)-type cyclometalated Ir(III) complex with -B(Mes)(2) group Ir-B, the CN ions can bind effectively with the boron atom in the -B(M-s)(2) group to furnish CN sensing ability through inducing phosphorescence changing of the concerned Ir(III) complex. Uniquely, with increasing the added amount of CN ions, loose and tight binding between CN and boron atom in the -B(M-s)(2) group of Ir-B can occur in sequence to destabilize metal-to-ligand charge transfer (MLCT) excited states and then form new MLCT excited states in Ir-B. Accompanying this process, the red phosphorescence of Ir-B can be effectively quenched by adding CN ions, while new yellow and green emission bands can appear in sequent with increasing the amount of added CN ions, showing CN sensing behavior with unique concentration distinguishing ability. In addition, the new phosphorescent CN sensor can possess detection limit (DL) as low as 4.3 x 10(-6) M and good selectivity to the CN ions. Clearly, these results can provide important information for developing new CN sensors with high performances. (C) 2020 Elsevier B.V. All rights reserved.