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The development of graphene-based electrodes for application in energy storage and energy harvesting devices represents an important strategy for producing wearable devices with requisites of flexibility and good electrochemical performance. Herein, the use of laser-induced graphene (LIG) has been explored as a simple and efficient method for the production of interdigitated microsupercapacitors (μSCs) and back electrodes for triboelectric nanogenerators (TENGs) active layers by direct production of graphene from Kapton polyimide and by the transference of the pattern to polydimethylsiloxane (a typical tribonegative layer for TENG). An open circuit voltage of 189.7 V, short circuit current of 39.8 μA, and power of 302.5 μW (power density of 20.2 μW/cm2) was observed for the conventional TENG while an areal capacitance of 2.5 mF/cm2 with good retention in the energy generation and cyclability in energy storage was observed for the microsupercapacitor. The most relevant aspect to be considered is a single-step method for transference of back-electrode to the Poly(dimethylsiloxane) requiring minimal processing steps for morphology control in the friction layer and self-powered behavior for integration of TENG/microsupercapacitor in a power unit cell.

The development of photonic devices has been largely benefitted by the offer of new flexible and stretchable materials. Many innovative components and devices have been developed for light-based applications. Presently it is recognized that integration of active and passive elements on flexible substrates will simplify many proposed photonic applications. For example, extensive variety of optical sensors integrated on biological tissues, optical waveguides based on polymer films, flexible organic interconnects, and imaging devices, are receiving large attention nowadays. Especially, the search for optical sources such as organic light emitting diodes and lasers are two booming areas. Flexible Random Lasers (FRLs) based on stretchable materials, in particular, have been object of intense research in the past few years.In this paper we present an overview of the FRLs literature, with emphasis in 2D and 3D materials, and the achievements and availability of new flexible organic and inorganic materials for FRLs. In Section 2 we present some basic ideas of Random Lasers (fundamentals, operation, and physical characteristics). Section 3 contains a detailed assessment of various types of FRLs based on biopolymers, electrospinning and natural fibers, silicones, semiconductor nanowires, perovskites, chiral molecules, polyethylene and polystyrene substrates. In Section 4 we present our perspective on new opportunities and emerging applications in this field.

The oncogenic human papillomavirus (HPV) is an excellent biomarker for cervical cancer screening. The present research reports the construction of an integrated sensor platform (biosensorMY11 and biosensorp53) for the impedimetric detection of the HPV L1 sequence and p53 tumor suppressor gene. The nanostructured biosensor is composed of electrosynthesized polypyrrole (PPy) and gold nanoparticles (AuNPs). Methodological strategies based on cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and atomic force microscopy (AFM) were used. The exposure of the genetic biosensors to molecular targets triggered changes in the analytical signals. Calibration plots for the biosensorMY11 showed a linear range between 0.001 to 100 pg μL−1 for all analyzed genotypes (HPV6, 11, 16, 18, 45, 53, 54, and 58). The detection limits were measured between 0.11 to 0.61 pg μL−1 and limits of quantification between 0.33 to 1.86 pg μL−1. The sensors exhibited reproducibility with a relative standard deviation of 4.21% and high repeatability (less than 2.5%). Two electrochemical profiles were obtained for high and low-risk HPV groups, suggesting the differential diagnosis using a degenerate oligonucleotide probe. Our results allow correlating the p53 gene expression in clinical samples infected with papillomavirus. The proposed biosensor represents an innovative device for the integrated monitoring of biomarkers related to cervical cancer with ultra-sensitive analytical performance.

The detection of traces of antibiotics in the environment involves expensive and time-consuming techniques. To circumvent these drawbacks, it is investigated in this work the detection of traces of polymyxin B from fluorescence resonant energy transfer systems based on pairs of rhodamine B (donor) and citrate-capped gold nanoparticles acceptors (Au NPs) applied in the detection of analytes from the desorption of rhodamine B from Au NPs under progressive incorporation of the analyte of interest (polymyxin B). Results revealed that the sensibility of these sensors is dependent on the relative concentration of gold nanoparticles in metal-dyes complexes applied in the recovery “turn-on” of fluorescence in the presence of traces of polymyxin B, with the limit-of-detection of 3.9 ppm.

The global need for high energy density and performing rechargeable batteries has led to the development of high-capacity silicon-based anode materials to meet the energy demands imposed to electrify plug-in vehicles to curtail carbon emissions by 2035. Unfortunately, the high theoretical capacity (4200 mA h g−1) of silicon by (de-)alloy mechanism is limited by its severe volume changes (ΔV ∼ 200% − 400%) during cycling for lithium-ion batteries (LIBs), while for sodium-ion batteries (NIBs) remain uncertain, and hence, compositing with carbons (C@Si) represent a promising strategy to enable the aforementioned practical application. The present review outlines the recent progress of biomass-derived Si-carbon composite (C@Si) anodes for LIBs and NIBs. In this perspective, we present different types of biomass precursors, silicon sources, and compositing strategies, and how these impact on the C@Si physicochemical properties and their electrochemical performance are discussed.

Background: Bothropic venoms cause intense local damage, pain, edema, and myonecrosis. Morus nigra L. (Moraceae) has several uses in folk medicine and can be a promising candidate for the treatment of several inflammatory disorders. Hypothesis/Purpose: The present study aims to evaluate the anti-inflammatory and antinociceptive effects of the ethanolic extract of Morus nigra L. (Mn-EtOH) on paw lesions induced by Bothrops jararacussu snake venom (BjcuV) in mice. Methods: UV–vis absorption of BjcuV was evaluated. A phytochemical study was performed, which led to the isolation and characterization of three compounds. These compounds were identified using spectrometric methods, namely LC–MS and NMR (1D and 2D), followed by the validation of their spectra with the data available in the literature. Further, the flavonoids i.e. rutin and quercetin (chemical markers of M. nigra), Mn-EtOH or Mn-EtOH-encapsulated electrospun fibers of Eudragit L100 (FB/Mn-EtOH), and Mn-EtOH-encapsulated microparticles of Eudragit L100 (MP/Mn-EtOH) were evaluated, in paw edema test induced by BjcuV. Results: UV–vis spectra showed the presence of phospholipases A2 as component of BjcuV. The chemical examination resulted in the isolation of β-sitosterol, quercetin-3-O-glucopyranoside, and kaempferol-3-O-glucopyranoside. Mn-EtOH, FB/Mn-EtOH, MP/Mn-EtOH, rutin, and quercetin reduced the local edema induced by BjcuV. The Mn-EtOH also prevented edema provoked by serotonin and bradykinin. Moreover, it reduced paw edema and peritoneal leukocyte infiltration induced by carrageenan, and decreased the mechanical hypernociception of BjcuV. Mn-EtOH exerted anti-inflammatory and antinociceptive effects, possibly by the inhibition of leukocyte migration and the modulation of serotonin and bradykinin actions. This anti-inflammatory activity was maintained even upon incorporation of the M. nigra extract into the drug delivery systems (i.e., Mn-EtOH-encapsulated FBs and MPs of Eudragit L100). Conclusion: These results reinforce the therapeutic potential of M. nigra in the treatment of inflammatory conditions, in addition to, its role as a complementary treatment of snakebites.