Optimizing textiles for enhanced passive radiative thermoregulation properties represents a significant step forward in technological innovation. To achieve this goal, we fabricated and characterized a visible-opaque infrared-modulator fabric (VOIMF) that can provide the human body with continuous thermoregulation at low temperatures. The fabric is a bilayer emitter composed of a polyethylene (PE) membrane and an ultrathin gold (Au) layer. The PE membrane contains randomly dispersed titanium dioxide (TiO2) microparticles (MPs). By flipping the fabric, we demonstrate that the VOIMF can modulate the emissivity toward the environment in the mid-infrared range, thereby providing a thermal comfort zone over a large temperature range of ∼ 10 °C (from 6.7 to 16.8 °C). Moreover, the VOIMF is opaque in the visible (VIS) range and exhibits a white appearance, similar to cotton, due to the high light scattering property of TiO2 MPs.

While human technology is ruled by determinism, biological systems exploit a subtle balance of control and stochasticity. This balance, evident in the morphogenesis of textural patterns imprinted on leaves, fur or skin can help hierarchize organisms both as a representative of their species and as unique individuals. In this study, we identified that, by exploiting electrochemistry, it is possible to generate such versatile but specific textures, to imprint patterns of a conducting polymer on a conducting substrate. It is shown that the 1D morphogenesis of conducting polymer dendrites on wires translates, on 2D surfaces, as highly heterogeneous coatings of dark spots, rosettes or marbled patterns. Despite their inherent stochasticity, these patterns are characteristic of the physical conditions they grew in, and particularly of the chemical content of the electroactive solution used for their electropolymerization. A statistical study demonstrates that these patterns could be used as fingerprints to physically tag the identity of a solution within a specific class. By the identification of a new electrochemical process which allows generating physical fingerprints with optical, electrical and chemical contrast on an electrode, this research paves the way toward a disruptive low-cost technology which could allow any end-user to generate personal tags on a glass slide or on a micro-chip, to engrave physically-encrypted personal information for various applications.

Conducting polymer dendrite (CPD) morphogenesis is an electrochemical process that enables in materio evolving intelligence in wetware devices. During CPD morphogenesis, voltage transients drive the physical evolution of electrically conductive structures, thereby programming their filtering properties as nonlinear analog devices. Whether studied in an electrochemical experiment or in neuromorphic devices, the dependence of the electrical properties of the electrogenerated structures on the chemical composition of their growth environment is still unreported. In this study, we report the existing interconnection between the nature and concentration of the electrolytes, electroactive compounds and co-solvents and the electrical and electrochemical properties of CPDs in an aqueous electrolyte. CPDs exhibit various chemical sensitivities in water: their morphology is highly dependent on the nature of the chemical resources available in their environment. The selection of these resources therefore critically influences morphogenesis. In addition, the concentrations of the different electrochemical species have varying impacts on growth dynamics, modulating the balance between thermodynamic and kinetic control over polymer electrosynthesis. By correlating the dependencies of these evolving objects with the availability of the chemical resources in an aqueous environment, this study offers guidelines to tune the degree of evolution of electronic materials in water and highlights potential avenues for their application. Such evolving hardware is envisioned to exploit the chemical complexity of real-world environments as part of information processing technologies.

Correction for ‘Diamond nanowires modified with poly[3-(pyrrolyl)carboxylic acid] for the immobilization of histidine-tagged peptides’ by Palaniappan Subramanian et al., Analyst, 2014, 139, 4343–4349, https://doi.org/10.1039/C4AN00146J.

Expression of concern for 'An impedimetric immunosensor based on diamond nanowires decorated with nickel nanoparticles' by Palaniappan Subramanian et al., Analyst, 2014, 139, 1726-1731, https://doi.org/10.1039/C3AN02045B.

Process variation is always a challenge to mitigate in electronics. This especially holds true for organic semiconductors, where reproducibility concerns hinder industrialization. Challenging this concept, it shows AC-electropolymerization to be a powerful platform for the development of morphology-dependent computing hardware, thanks precisely to its intrinsic stochasticity. The findings reveal that electropolymerized polymer dendrite networks exhibit a complex structure-operation relationship that allows to implement nearly linear to nonlinear functions. Moreover, dendritic networks can integrate a limitless number of inputs from their environment, which can be used to the advantage in the context of in materio computing to discriminate between different spatiotemporal inputs. These results position electropolymerization as a pivotal technique for the bottom-up implementation of computationally powerful objects. This study anticipates this study to help shifting the negative perception of variability in the material science community and promote the electropolymerization framework as a foundation for the development of a new generation of hardware defined by its topological richness.

The successful covalent linking of green fluorescence protein and streptavidin to patterned benzophenone-modified boron-doped diamond (BDD) electrodes is demonstrated. Photoreactive benzophenone moieties were covalently grafted to oxidized diamond surfaces via an esterification reaction. Patterned BDD surfaces were obtained using a UV/ozone lithographic approach either on hydrogen-terminated BDD or on poly(ethylene)-glycol-modified BDD surfaces. UV light (lambda = 365 nm) irradiation of the patterned BDD surfaces in the presence of green fluorescence protein (GFP) or streptavidin resulted in the covalent immobilization of the proteins. The presence of poly(ethylene) glycol chains reduces significantly the nonspecific adsorption of the proteins. The success of the photoimmobilization of streptavidin was evidenced through biomolecular interaction with avidin. The preservation of the biological activity was furthermore underlined by photoimmobilization of peptides directly onto benzophenone modified BDD using a photomask.

The release of organophosphates into the natural environment may directly and indirectly affect human health and cause severe damage to environmental ecosystems, thus raising global concern. In addition, some of these organophosphorus compounds (OPs) have been weaponized. Among them, Sarin, which is an OP-based nerve agent, has already been used as massive chemical weapons emphasising the need for their detection. In this study, we propose the development of a new nanomaterial based on porous silicon (PSi) decorated with copper particles for the detection of dimethyl methylphosphonate (DMMP), a sarin simulant. We took advantage of the large surface area of PSi and the specificity towards DMMP brought by copper particle decoration. Two types of PSi porosities (60 % and 80 %), were used while experimental copper particle deposition method was evaluated to ensure a uniform distribution within porous texturation. Then, and for the first time, the presence of DMMP was detected bimodally using FT-IR and mass spectrometry from the same PSi-Cu surface. We demonstrated enhanced specificity for DMMP detection using porous silicon decorated with copper particles (PSi-Cu) compared to unmodified PSi. Several characteristic IR absorption bands of DMMP were clearly observed, including peaks at 1319 and 925 cm(-1) corresponding to the symmetric and asymmetric deformation modes of the P-CH3 group, the P-O-C stretching mode at 830 cm(-1), and the PO stretching vibration at 1246 cm(-1). In addition, the PSi-Cu surface enabled matrix-free surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS), revealing a strong interaction between DMMP and copper. The dominant mass spectral peak at m/z = 186, assigned to the [M + Cu](+) adduct, confirms a Lewis acid-type interaction between DMMP and the Cu-decorated surface. This study aimed to demonstrate, for the first time, the feasibility of combining FT-IR spectroscopy and matrix-free SALDI-MS for DMMP detection on a single, untreated PSi-Cu platform. Although the sensitivity, response time, and recovery time of the system are not yet state-of-the-art, our results highlight the potential of this dual-mode analytical approach for analyzing complex samples on same surface making it an invaluable tool in fields such as chemistry, pharmaceuticals, forensics, and environmental science.

This study presents a methodical procedure for optimizing laser desorption/ionization mass spectrometry (LDI-MS) supports using porous silicon (PSi) substrates. The approach involves the use of substituted benzyl-pyridinium salts (thermometer ions) to obtain one metric that assesses analyte fragmentation (the effective temperature of vibration). Porous silicon substrates were synthesized via electrochemical etching of p-type silicon wafers (10-20 mΩ·cm), with etching parameters adjusted to vary porosity while maintaining a layer thickness between 700 and 1200 nm. The results revealed that PSi substrates with 40-60% porosity achieved the lowest fragmentation levels. This finding was validated through the analysis of N-acetyl glucosamine, a carbohydrate, which confirmed the effective temperature trend. Further analysis involving peptides, specifically P14R and a peptide mix (Peptide Calibration Standard II, Bruker), demonstrated that the optimized PSi substrates enabled the desorption and ionization of peptides with a maximum mass at m/z 2465, corresponding to ACTH clip 1-17. These results highlight the critical role of substrate porosity in minimizing analyte fragmentation and enhancing LDI-MS performance.

In this study, we present a new chemical sensor based on a functionalized porous silicon and sensitive to dimethyl methyl phosphonate (DMMP), a simulant of sarin gas, known as one of the most toxic warfare agents. The porous silicon was prepared by anodising a boron-doped p-Si (100) wafer. A metal oxide TiO2 layer was then deposited by thermal evaporation of Ti and oxidized under atmospheric conditions to form a TiO2 film which was used as a reactive coating. The characterization of the PSi and TiO2/PSi films was investigated using SEM, EDX and XPS spectroscopies. The results indicated that the TiO2 was well incorporated on the surface and slightly inside the porous silicon layer. FT-IR studies were then carried out before and after exposure to DMMP and the detection performance was compared with PSi. The results obtained showed that our surfaces have the ability to detect DMMP down to 0.5 ppm compared to uncoated PSi layer. We have also shown that a TFA pre-treatment of our TiO2 modified PSi, prior the exposure to DMMP, is crucial for increasing its sensitivity and that our sensor can be reused several times with a simple hexane cleaning step, a key criterion for routine applications.

Alzheimer's disease (AD) is nowadays the prominent cause of senile dementia. This pathology is characterized by aggregation of neurofibrillary tangles in cells and by the accumulation of amyloid plaques in the brain. Noteworthy, a phosphorylated protein (tau protein) and a peptide presenting two overlapping sequences of 40 or 42 residues named β-amyloid peptides 1-40 (Aβ 1-40) and 1-42 (Aβ 1-42), respectively, were related to such deleterious phenomena. Singularly, the neurotoxicity was primarily attributed to the amyloid peptide Aβ 1-42 form due to its capacity to fold into beta-sheets rendering it insoluble thus causing subsequent aggregation and accumulation in vivo. Regarding AD diagnosis relying on mass spectrometry, Aβ 1-42 and/or Aβ 1-40 were considered as relevant biomarkers being measured in cerebrospinal fluids (CSF), blood and urine. Under that context, we aimed at implementing an innovative method to evidence the depletion of circulating Aβ 1-42 amyloid peptide compared to the shorter Aβ 1-40 form indicating a pathologic state. We investigated Surface-Assisted Laser Desorption/Ionization Mass Spectrometry (SALDI-MS) in order to monitor the Aβ 1-42/Aβ 1-40 ratio without any prior sample treatment or enrichment. Taking into account that β-amyloid peptide and 1-42 can aggregate into beta-sheets depending on the experimental conditions, specific attention was devoted to sample integrity monitoring performed by circular dichroism experiments during SALDI-MS method development.

Expression of concern for 'Localized electropolymerization on oxidized boron-doped diamond electrodes modified with pyrrolyl units' by Paolo Actis et al., Phys. Chem. Chem. Phys., 2006, 8, 4924-4931, https://doi.org/10.1039/B611735J.

This study presents a methodical procedure for optimizing laser desorption/ionization mass spectrometry (LDI-MS) supports using porous silicon (PSi) substrates. The approach involves the use of substituted benzyl-pyridinium salts (thermometer ions) to obtain one metric that assesses analyte fragmentation (the effective temperature of vibration). Porous silicon substrates were synthesized via electrochemical etching of p-type silicon wafers (10-20 mΩ⋅cm), with etching pa-rameters adjusted to vary porosity while maintaining a layer thickness between 700 and 1200 nm. The results revealed that PSi substrates with 40-60% porosity achieved the lowest fragmentation levels. This finding was validated through the analysis of N-Acetyl glucosamine, a carbohydrate, which confirmed the effective temperature trend. Further analysis involving peptides, specifically P14R and a peptide mix (Peptide Calibration Standard II, Bruker), demonstrated that the optimized PSi substrates enabled the desorption and ionization of peptides with a maximum mass at m/z 2465, corresponding to ACTH clip 1-17. These results highlight the critical role of substrate porosity in minimizing analyte fragmentation and enhancing LDI-MS performance.

Correction for 'Diamond nanowires modified with poly[3-(pyrrolyl)carboxylic acid] for the immobilization of histidine-tagged peptides' by Palaniappan Subramanian et al., Analyst, 2014, 139, 4343-4349, https://doi.org/10.1039/C4AN00146J.

One of the serious challenges facing modern point-of-care (PoC) molecular diagnostic platforms relate to reliable detection of low concentration biomarkers such as nucleic acids or proteins in biological samples. Non-specific analyte-receptor interactions due to competitive binding in the presence of abundant molecules, inefficient mass transport and very low number of analyte molecules in sample volume, in general pose critical hurdles for successful implementation of such PoC platforms for clinical use. Focusing on these specific challenges, this work reports a unique PoC biosensor that combines the advantages of nanoscale biologically-sensitive field-effect transistor arrays (BioFET-arrays) realized in a wafer-scale top-down nanofabrication as high sensitivity electrical transducers with that of sophisticated molecular programs (MPs) customized for selective recognition of analyte miRNAs and amplification resulting in an overall augmentation of signal transduction strategy. The MPs realize a programmable universal molecular amplifier (PUMA) in fluidic matrix on chip and provide a biomarkertriggered exponential release of small nucleic acid sequences easily detected by receptor-modified BioFETs. A common miRNA biomarker LET7a was selected for successful demonstration of this novel biosensor, achieving limit of detection (LoD) down to 10 fM and wide dynamic ranges (10 pM - 10 nM) in complex physiological solutions. As the determination of biomarker concentration is implemented by following the electrical signal related to analyte-triggered PUMA in time-domain instead of measuring the threshold shifts of BioFETs, and circumvents direct hybridization of biomarkers at transducer surface, this new strategy also allows for multiple usage ( >3 times) of the biosensor platform suggesting exceptional cost-effectiveness for practical use.

Despite several demonstrations of electrochemical devices with limits of detection (LOD) of 1 cell/mL, the implementation of single-cell bioelectrochemical sensor arrays has remained elusive due to the challenges of scaling up. In this study, we show that the recently introduced nanopillar array technology combined with redox-labeled aptamers targeting epithelial cell adhesion molecule (EpCAM) is perfectly suited for such implementation. Combining nanopillar arrays with microwells determined for single cell trapping directly on the sensor surface, single target cells are successfully detected and analyzed. This first implementation of a single-cell electrochemical aptasensor array, based on Brownian-fluctuating redox species, opens new opportunities for large-scale implementation and statistical analysis of early cancer diagnosis and cancer therapy in clinical settings.