Interstitial lung abnormality evaluated by an automated quantification system: prevalence and progression rate.

BACKGROUND: Despite the importance of recognizing interstitial lung abnormalities, screening methods using computer-based quantitative analysis are not well developed, and studies on the subject with an Asian population are rare. We aimed to identify the prevalence and progression rate of interstitial lung abnormality evaluated by an automated quantification system in the Korean population. METHODS: A total of 2,890 healthy participants in a health screening program (mean age: 49 years, men: 79.5%) with serial chest computed tomography images obtained at least 5 years apart were included. Quantitative lung fibrosis scores were measured on the chest images by an automated quantification system. Interstitial lung abnormalities were defined as a score ≥ 3, and progression as any score increased above baseline. RESULTS: Interstitial lung abnormalities were identified in 251 participants (8.6%), who were older and had a higher body mass index. The prevalence increased with age. Quantification of the follow-up images (median interval: 6.5 years) showed that 23.5% (59/251) of participants initially diagnosed with interstitial lung abnormality exhibited progression, and 11% had developed abnormalities (290/2639). Older age, higher body mass index, and higher erythrocyte sedimentation rate were independent risk factors for progression or development. The interstitial lung abnormality group had worse survival on follow-up (5-year mortality: 3.4% vs. 1.5%; P = 0.010). CONCLUSIONS: Interstitial lung abnormality could be identified in one-tenth of the participants, and a quarter of them showed progression. Older age, higher body mass index and higher erythrocyte sedimentation rate increased the risk of development or progression of interstitial lung abnormality.

Antifibrotic Agents in Rheumatoid Arthritis-Associated Interstitial Lung Disease: A Systematic Review and Meta-Analysis.

BACKGROUND: Rheumatoid arthritis-associated interstitial lung disease (RA-ILD) is a common extra-articular clinical manifestation of rheumatoid arthritis (RA) that has negative impacts on morbidity and mortality. In addition, there has been no proven treatment for RA-ILD to date. Thus, we planned a meta-analysis of a literature search to confirm the clinical effects of antifibrotic agents in RA-ILD patients. MATERIALS AND METHODS: We conducted the literature search in Ovid MEDLIVE® databases, Cochrane Library databases, EMBASE, and KoreaMed and identified references elucidating the role of nintedanib or pirfenidone in adult patients with RA-ILD. Among the identified studies, those with comparative interventions, complete results of clinical trials, and available full text were included in the analysis. The primary outcome was the effect of the antifibrotic agent on disease progression in RA-ILD patients assessed with a mean difference in the change of forced vital capacity (FVC) and the proportion of patients with an increase in percent predicted FVC of 10% or more over 52 weeks. Analysis for heterogeneity was assessed through I2 statistics. Meta-analysis with a fixed effect model was performed on changes in FVC. RESULTS: A total of 153 articles were identified through database searches, of which 28 were excluded because of duplication. After additional screening, 109 studies were selected with full text and two articles qualified for analysis according to the set inclusion and exclusion criteria. As a result, two randomized controlled studies were selected, comparing nintedanib and pirfenidone to placebo, respectively. The meta-analysis revealed that antifibrotic agents showed a significant reduction in FVC decline compared to placebo in patients with RA-ILD (mean difference, 88.30; 95% CI, 37.10-139.50). Additionally, there were significantly fewer patients experienced an increase in percent predicted FVC of 10% or more in the antifibrotic agent group compared to the placebo group (Odds ratio 0.42; 95% CI 0.19-0.95, p = 0.04). There was no significant heterogeneity between the two included studies (χ2 = 0.35, p = 0.0007, I2 = 0%). CONCLUSIONS: The meta-analysis suggests that nintedanib and pirfenidone may have clinical utility in reducing disease progression in patients with RA-ILD. Further research is needed to confirm the clinical benefits of antifibrotic agents in RA-ILD.

Revealing Redox Behavior of Molybdenum Disulfide and Its Application as Rechargeable Antioxidant Reservoir.

Molybdenum disulfide (MoS2) is a representative two-dimensional transition metal dichalcogenide and has a unique electronic structure and associated physicochemical properties. The redox property of MoS2 has recently attracted significant attention from various fields, such as biomedical applications. Intriguingly, MoS2 functions as an antioxidant in certain applications and as a pro-oxidant in others. We use the mediated electrochemical probing method to understand the redox behavior of MoS2. This method reveals that MoS2 (i) has a reversible and fast redox activity at a mild potential (between -0.20 and +0.25 V vs Ag/AgCl), (ii) functions as an antioxidant for molecules that have different redox mechanisms (electron or hydrogen atom transfer), and (iii) is electrochemically or molecularly rechargeable. Finally, we show that MoS2 reduces oxidized molecules more efficiently than the potent natural antioxidant, curcumin. This study enhances our understanding of MoS2 and shows its potential as an advanced antioxidant reservoir.

Fibrosis score predicts mortality in patients with fibrotic hypersensitivity pneumonitis.

Background: Variable clinical courses make it challenging to predict mortality resulting from fibrotic hypersensitivity pneumonitis (HP). This study evaluated the usefulness of radiologic parameters for predicting mortality in patients with fibrotic HP. Methods: Clinical data and high-resolution computed tomography (HRCT) images, which were scored for reticulation, honeycombing, ground glass opacity (GGO), consolidation, and mosaic attenuation (MA) by visual assessment, were retrospectively analyzed in a total of 101 patients with fibrotic HP (all biopsy-proven cases). Fibrosis score was defined as the sum of reticulation and honeycombing scores. Results: The mean age of the 101 patients was 58.9 years, and 60.4% were females. During the follow-up (median: 55.5 months; interquartile range: 37.7-89.0 months), the 1-, 3-and 5-year mortality rates were 3.9, 16.8, and 32.7%, respectively. The non-survivors were older and had significantly lower lung function and minimum oxygen saturation during the 6-min walk test than the survivors. The non-survivors had higher scores of reticulation, honeycombing, GGO, fibrosis, and MA on HRCT than survivors. In the multivariable Cox analysis, reticulation, GGO, and fibrosis scores were independent prognostic factors for mortality in patients with fibrotic HP, as well as age. Fibrosis score showed great performance for predicting the 5-year mortality (AUC = 0.752, p < 0.001) and higher mortality was recorded for patients with high fibrosis score (≥12.0%) (the mean survival time: 58.3 vs. 146.7 months, p < 0.01) than those without. Conclusion: Our results suggest that radiologic fibrosis score may be a useful predictor of mortality in patients with fibrotic HP.

Cyclo[2]carbazole[2]pyrrole: a preorganized calix[4]pyrrole analogue.

A cyclo[2]carbazole[2]pyrrole (2) consisting of two carbazoles and two pyrroles has been synthesized by directly linking the carbazole 1- and 8-carbon atoms to the pyrrole α-carbon atoms. Macrocycle 2 is an extensively conjugated 16-membered macrocyclic ring that is fixed in a pseudo-1,3-alternate conformation. This provides a preorganized anion binding site consisting of two pyrrole subunits. 1H NMR spectroscopic analysis revealed that only the two diagonally opposed pyrrole NH protons, as opposed to the carbazole protons, take part in anion binding. Nevertheless, cyclo[2]carbazole[2]pyrrole 2 binds representative anions with higher affinity in CD2Cl2 than calix[4]pyrrole (1), a well-studied non-conjugated tetrapyrrole macrocycle that binds anions via four pyrrolic NH hydrogen bond interactions. On the basis of computational studies, the higher chloride anion affinity of receptor 2 relative to 1 is rationalized in terms of a larger binding energy and a lower host strain energy associated with anion complexation. In the presence of excess fluoride or bicarbonate anions, compound 2 loses two pyrrolic NH protons to produce a stable dianionic macrocycle [2-2H]2- displaying a quenched fluorescence.

Calix[4]pyrrole-Based Molecular Capsule: Dihydrogen Phosphate-Promoted 1:2 Fluoride Anion Complexation.

A molecular capsule (1) consisting of two calix[4]pyrroles connected via ethylene diamide linkers has been prepared as an anion receptor. 1H NMR spectroscopic studies carried out in CD2Cl2 revealed that receptor 1 recognizes a variety of anions with different binding modes and stoichiometries. For instance, receptor 1 binds fluoride and acetate with 1:2 receptor/anion stoichiometry and other test anions with 1:1 stoichiometry in solution when their respective tetrabutylammonium (TBA+) salts were used. In contrast, with tetraethylammnium (TEA+) salts, receptor 1 forms 1:2 complexes with chloride and bromide in addition to fluoride, overcoming expected Columbic repulsions between the anions co-bound in close proximity. Receptor 1 is also able to bind oxoanions, such as oxalate (C2O42-), dihydrogen phosphate (H2PO4-), sulfate (SO42-), and hydrogen pyrophosphate (HP2O73-), in the form of 1:1 complexes as the result of presumed cooperation between the two calix[4]pyrrole subunits. The selectivity of receptor 1 for fluoride versus dihydrogen phosphate varies depending on their relative concentrations. For instance, in the presence of less than 1.0 equiv of an equimolar mixture of fluoride and dihydrogen phosphate, receptor 1 shows high selectivity for dihydrogen phosphate. In contrast, in the presence of ≥2.0 anion equiv, receptor 1 binds fluoride preferentially, forming a 1:2 complex. Moreover, when treated with F-, the preformed 1:1 H2PO4- complex of receptor 1 is converted to the corresponding 1:2 receptor/fluoride complex with the release of the prebound dihydrogen phosphate anion. As inferred from gas-phase computations, this seemingly counterintuitive behavior is rationalized in terms of the precomplexed dihydrogen phosphate serving to reduce the reorganization energy required to bind two fluoride anions. The presence of a water molecule in addition to the bound fluoride anions may also favor the formation of the 1:2 F- complex. The present study provides a new approach for fine-tuning the binding selectivity of polytopic anion receptors.

Radio Frequency Heating of Washable Conductive Textiles for Bacteria and Virus Inactivation.

The ongoing COVID-19 pandemic has increased the use of single-use medical fabrics such as surgical masks, respirators, and other personal protective equipment (PPE), which have faced worldwide supply chain shortages. Reusable PPE is desirable in light of such shortages; however, the use of reusable PPE is largely restricted by the difficulty of rapid sterilization. In this work, we demonstrate successful bacterial and viral inactivation through remote and rapid radio frequency (RF) heating of conductive textiles. The RF heating behavior of conductive polymer-coated fabrics was measured for several different fabrics and coating compositions. Next, to determine the robustness and repeatability of this heating response, we investigated the textile's RF heating response after multiple detergent washes. Finally, we show a rapid reduction of bacteria and virus by RF heating our conductive fabric. 99.9% of methicillin-resistant Staphylococcus aureus (MRSA) was removed from our conductive fabrics after only 10 min of RF heating; human cytomegalovirus (HCMV) was completely sterilized after 5 min of RF heating. These results demonstrate that RF heating conductive polymer-coated fabrics offer new opportunities for applications of conductive textiles in the medical and/or electronic fields.

Automated quantification system predicts survival in rheumatoid arthritis-associated interstitial lung disease.

OBJECTIVE: The prognosis of RA-associated interstitial lung disease (RA-ILD) is difficult to predict because of the variable clinical course. This study aimed to determine the prognostic value of an automated quantification system (AQS) in RA-ILD. METHODS: We retrospectively analysed the clinical data and high-resolution CT (HRCT) images of 144 patients with RA-ILD. Quantitative lung fibrosis (QLF, sum of reticulation and traction bronchiectasis) and ILD [QILD; sum of QLF, honeycombing (QHC), and ground-glass opacity (QGG)] scores were measured using the AQS. RESULTS: The mean age was 61.2 years, 43.8% of the patients were male, and the 5-year mortality rate was 30.5% (median follow-up, 52.2 months). Non-survivors showed older age, higher ESR and greater AQS scores than survivors. In multivariable Cox analysis, higher QLF, QHC and QILD scores were independent prognostic factors along with older age and higher ESR. In receiver-operating characteristic curve analysis, the QLF score showed better performance in predicting 5-year mortality than the QHC and QGG scores but was similar to the QILD score. Patients with high QLF scores (≥12% of total lung volume) showed higher 5-year mortality (50% vs 17.4%, P < 0.001) than those with low QLF scores and similar survival outcome to patients with idiopathic pulmonary fibrosis (IPF). Combining with clinical variables (age, ESR) further improved the performance of QLF score in predicting 5-year mortality. CONCLUSION: QLF scores might be useful for predicting prognosis in patients with RA-ILD. High QLF scores differentiate a poor prognostic phenotype similar to IPF.

Preoperative electromagnetic navigation bronchoscopy-guided one-stage multiple-dye localization for resection of subsolid nodules: A single-center pilot study.

BACKGROUND: Electromagnetic navigation bronchoscopy (ENB)-guided transbronchial dye marking and video-assisted thoracoscopic surgery (VATS) is an emerging technique that enables successful resection of multiple small subsolid pulmonary nodules. The aim of this study was to evaluate the accuracy and safety of preoperative ENB-guided transbronchial multiple dye localization for VATS resection of subsolid pulmonary nodules. METHODS: As a single-center pilot study, we recruited patients with at least two small or subsolid pulmonary nodules. Multiple-dye localization was performed by intraoperative ENB-guided transbronchial injection of an indigo carmine dye. The patients underwent VATS for sublobar resection immediately after localization. The accuracy of ENB-guided dye marking was checked. RESULTS: ENB-guided one-stage multiple dye localization was conducted for 18 pulmonary nodules in seven patients between September 2018 and December 2019. The mean diameter of the pulmonary nodules was 9.3 mm (range, 4-18) and the mean distance from the pleura to pulmonary nodule was 6 mm (range, 1-17 mm). ENB-guided transbronchial multiple dye localization was successfully performed in 94.4% (17/18), and the accuracy of ENB-guided dye marking was 88.2% (15/17). When two nodules were not seen in intraoperative fields, anatomical sublobar resection was performed. There was no conversion to thoracotomy and operative mortalities. Among the seven patients, only one patient showed mild intrabronchial bleeding but stopped spontaneously. The changes in lung function after multiple wedge resections (-1.6% to 24.8%) were tolerable level. CONCLUSIONS: ENB-guided one-stage transbronchial dye localization showed accurate and safe intraoperative identification of multiple subsolid pulmonary nodules. A large scale prospective clinical study is warranted.

Electronic and Optical Property Control of Polycation/MXene Layer-by-Layer Assemblies with Chemically Diverse MXenes.

MXenes, 2D nanomaterials derived from ceramic MAX phases, have drawn considerable interest in a wide variety of fields including energy storage, catalysis, and sensing. There are many possible MXene compositions due to the chemical and structural diversity of parent MAX phases, which can bear different possible metal atoms "M", number of layers, and carbon or nitrogen "X" constituents. Despite the potential variety in MXene types, the bulk of MXene research focuses upon the first MXene discovered, Ti3C2T. With the recent discovery of polymer/MXene multilayer assemblies as thin films and coatings, there is a need to broaden the accessible types of multilayers by including MXenes other than Ti3C2Tz; however, it is not clear how altering the MXene type influences the resulting multilayer growth and properties. Here, we report on the first use of MXenes other than Ti3C2Tz, specifically Ti2CTz and Nb2CTz, for the layer-by-layer (LbL) assembly of polycation/MXene multilayers. By comparing these MXenes, we evaluate both how changing M (Ti vs Nb) and "n" (Ti3C2Tzvs Ti2CTz) affect the growth and properties of the resulting multilayer. Specifically, the aqueous LbL assembly of each MXene with poly(diallyldimethylammonium) into films and coatings is examined. Further, we compare the oxidative stability, optoelectronic properties (refractive index, absorption coefficient, optical conductivity, and direct and indirect optical band gaps), and the radio frequency heating response of each multilayer. We observe that MXene multilayers with higher "n" are more electrically conductive and oxidatively stable. We also demonstrate that Nb2CTz containing films have lower optical band gaps and refractive indices at the cost of lower electrical conductivities as compared to their Ti2CTz counterparts. Our work demonstrates that the properties of MXene/polycation multilayers are highly dependent on the choice of constituent MXene and that the MXene type can be altered to suit specific applications.

Diagnostic Performance of Electromagnetic Navigation Bronchoscopy-Guided Biopsy for Lung Nodules in the Era of Molecular Testing.

Electromagnetic navigation bronchoscopy (ENB) is an emerging technique used to evaluate peripheral lung lesions. The aim of this study was to determine the diagnostic yield, safety profile, and adequacy of specimens obtained using ENB for molecular testing. This single-center, prospective pilot study recruited patients with peripheral pulmonary nodules that were not suitable for biopsy via percutaneous transthoracic needle biopsy methods. The possibility of molecular testing, including epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), and programmed death ligand 1 (PD-L1), was identified with non-small cell lung cancer (NSCLC) tissue obtained using ENB. ENB-guided biopsy was performed on 30 pulmonary nodules in 30 patients. ENB-guided biopsy was successfully performed in 96.6% (29/30) of cases, but one case failed to approach the target lesion. The diagnostic accuracy of ENB-guided biopsy was 68.0% (17/25). Biopsy-related pneumothorax occurred in one patient and there was no major bleeding or deaths related to the procedure. Among 13 patients diagnosed with NSCLC, molecular testing was successfully performed in 92.3% (12/13). ENB-guided biopsy demonstrated acceptable accuracy and excellent sample adequacy, with a high possibility of achieving molecular testing and a good safety profile to evaluate peripheral pulmonary nodules, even when the percutaneous approach was difficult and/or dangerous.

Diagnostic yield and safety of biopsy guided by electromagnetic navigation bronchoscopy for high-risk pulmonary nodules.

BACKGROUND: Electromagnetic navigation bronchoscopy (ENB) is a useful method to obtain tissue for peripheral lung nodules. We aimed to understand the diagnostic yield and safety profile in high-risk pulmonary nodules that cannot be accessed by percutaneous transthoracic needle biopsy. METHODS: In this single-center retrospective study, we reviewed patients who underwent ENB for high-risk pulmonary nodules. All procedures were performed under moderate sedation using intravenous midazolam and fentanyl. RESULTS: A total of 100 pulmonary nodules in 90 patients were subjected to ENB between October 2018 and May 2020. The median age of the study population was 66 (59-73). The mean diameter of the lung nodules was 27.9 mm. The diagnostic yield of ENB-guided biopsy was 53.0%. Although the nodule size (odds ratio: 1.055, p = 0.007) and positive bronchus sign (odds ratio: 2.918, p = 0.020) were associated with the diagnostic yield during univariate analysis, nodule size was the only independent variable on the multivariable analysis. Interestingly, the diagnostic yield showed an upward trend after 60 cases, from 45%-65%. Procedure-related complications were reported in 16 cases; among these, pneumothorax occurred in three cases, and four cases experienced moderate bleeding. No instance of major bleeding or death was linked to ENB-guided biopsy. CONCLUSION: ENB-guided biopsy for high-risk pulmonary nodules demonstrated an acceptable diagnostic yield and good safety profile. Moreover, the diagnostic yield was associated with nodule size and procedure experience.

The effect of continuity of care on medical costs in patients with chronic shoulder pain.

Unnecessary surgery could be prevented through continuity of care (COC). The present study aimed to investigate the relationships between COC, surgery and cost associated with chronic shoulder pain. We used the Health Insurance Review and Assessment Service national patient sample (HIRA-NPS) in 2017. A total of 1717 patients were included. Bice-Boxerman Continuity of Care Index was used as the indicator for measuring the COC. Occurrence of surgery, associated costs, and direct medical costs were analysed. Logistic regression, a two-part model with recycled predictions and generalized linear model with gamma distribution were used. The majority of patients were 40-65 years old (high COC: 68.4%; low COC: 64.4%). The odds ratio (OR) for surgery was 0.41 in the high-COC group compared to the low COC group (95% CI, 0.20 to 0.84). Direct medical cost was 14.09% (95% CI, 8.12% to 19.66%) and 58.00% lower in surgery cost (95% CI, 57.95 to 58.05) in the high-COC group. Interaction with COC and shoulder impingement syndrome was significant lower in direct medical cost (15.05% [95% CI, 1.81% to 26.51%]). High COC was associated with low medical cost in patients diagnosed with chronic shoulder pain.

Radio frequency heating and material processing using carbon susceptors.

Carbon nanomaterials have been shown to rapidly evolve heat in response to electromagnetic fields. Initial studies focused on the use of microwaves, but more recently, it was discovered that carbon nanomaterial systems heat in response to electric fields in the radio frequency range (RF, 1-200 MHz). This is an exciting development because this range of radio frequencies is safe and versatile compared to microwaves. Additional RF susceptor materials include other carbonaceous materials such as carbon black, graphite, graphene oxide, laser-induced graphene, and carbon fibers. Such conductive fillers can be dispersed in matrices such as polymer or ceramics; these composites heat rapidly when stimulated by electromagnetic waves. These findings are valuable for materials processing, where volumetric and/or targeted heating are needed, such as curing composites, bonding multi-material surfaces, additive manufacturing, chemical reactions, actuation, and medical ablation. By changing the loading of these conductive RF susceptors in the embedding medium, material properties can be customized to achieve different heating rates, with possible other benefits in thermo-mechanical properties. Compared to traditional heating and processing methods, RF heating provides faster heating rates with lower infrastructure requirements and better energy efficiency; non-contact RF applicators or capacitors can be used for out-of-oven processing, allowing for distributed manufacturing.

Primary Malignant Mesothelioma of the Peritoneum Mistaken for Peritoneal Tuberculosis due to Elevated Cancer Antigen 125.

Adifferential diagnosis of ascites is always challenging for physicians. Peritoneal tuberculosis is particularly difficult to distinguish from peritoneal carcinomatosis because of the similarities in clinical manifestations and laboratory results. Although the definitive diagnostic method for ascites is to take a biopsy of the involved tissues through laparoscopy or laparotomy, there are many limitations in performing biopsies in clinical practice. For this reason, physicians have attempted to find surrogate markers that can substitute for a biopsy as a confirmative diagnostic method for ascites. CA 125, which is known as a tumor marker for gynecological malignancies, has been reported to be a biochemical indicator for peritoneal tuberculosis. On the other hand, the sensitivity of serum CA 125 is low, and CA 125 may be elevated due to other benign or malignant conditions. This paper reports the case of a 66-year-old male who had a moderate amount of ascites and complained of dyspepsia and a febrile sensation. His abdominal CT scans revealed a conglomerated mass, diffuse omental infiltration, and peritoneal wall thickening. Initially, peritoneal tuberculosis was suspected due to the clinical symptoms, CT findings, and high serum CA 125 levels, but non-specific malignant cells were detected on cytology of the ascitic fluid. Finally, he was diagnosed with primary malignant peritoneal mesothelioma after undergoing a laparoscopic biopsy.

Small triiminopyrrolic molecular cage with high affinity and selectivity for fluoride.

A small molecular cage (4) with high affinity and complete selectivity for fluoride to the limit of detection over other competing small anions was synthesized. Cage 4 was also found to retain the encapsulated fluoride anion within its cavity even after one or two pyrrolic NH protons were subject to deprotonation.

Synthesis and Anion Recognition Features of a Molecular Cage Containing Both Hydrogen Bond Donors and Acceptors.

A molecular cage, macrobicycle 2, containing amide and pyrrole groups as hydrogen-bonding donors and imine groups as hydrogen-bonding acceptors has been synthesized. Compound 2 was found to recognize tetrahedral oxyanions with high affinities, such as H2PO4-, HSO4-, SO42-, and HP2O73-, as well as the spherical halide anions, in chloroform. A single-crystal X-ray diffraction analysis revealed that compound 2 formed a 1:1 complex with H2PO4- in the solid state.

Selective Solid-Liquid and Liquid-Liquid Extraction of Lithium Chloride Using Strapped Calix[4]pyrroles.

LiCl is a classic "hard" ion salt that is present in lithium-rich brines and a key component in end-of-life materials (that is, used lithium-ion batteries). Its isolation and purification from like salts is a recognized challenge with potential strategic and economic implications. Herein, we describe two ditopic calix[4]pyrrole-based ion-pair receptors (2 and 3), that are capable of selectively capturing LiCl. Under solid-liquid extraction conditions, using 2 as the extractant, LiCl could be separated from a NaCl/KCl salt mixture containing as little as 1 % LiCl with circa 100 % selectivity, while receptor 3 achieved similar separations when the LiCl level was as low as 200 ppm. Under liquid-liquid extraction conditions using nitrobenzene as the non-aqueous phase, the extraction preference displayed by 2 is KCl>NaCl>LiCl. In contrast, 3 exhibits high selectivity towards LiCl over NaCl and KCl, with no appreciable extraction being observed for the latter two salts.

Skin-Attachable, Stretchable Electrochemical Sweat Sensor for Glucose and pH Detection.

As part of increased efforts to develop wearable healthcare devices for monitoring and managing physiological and metabolic information, stretchable electrochemical sweat sensors have been investigated. In this study, we report on the fabrication of a stretchable and skin-attachable electrochemical sensor for detecting glucose and pH in sweat. A patterned stretchable electrode was fabricated via layer-by-layer deposition of carbon nanotubes (CNTs) on top of patterned Au nanosheets (AuNS) prepared by filtration onto stretchable substrate. For the detection of glucose and pH, CoWO4/CNT and polyaniline/CNT nanocomposites were coated onto the CNT-AuNS electrodes, respectively. A reference electrode was prepared via chlorination of silver nanowires. Encapsulation of the stretchable sensor with sticky silbione led to a skin-attachable sweat sensor. Our sensor showed high performance with sensitivities of 10.89 µA mM-1 cm-2 and 71.44 mV pH-1 for glucose and pH, respectively, with mechanical stability up to 30% stretching and air stability for 10 days. The sensor also showed good adhesion even to wet skin, allowing the detection of glucose and pH in sweat from running while being attached onto the skin. This work suggests the application of our stretchable and skin-attachable electrochemical sensor to health management as a high-performance healthcare wearable device.

Fabrication of High-Sensitivity Skin-Attachable Temperature Sensors with Bioinspired Microstructured Adhesive.

In this study, we demonstrate the fabrication of a highly sensitive flexible temperature sensor with a bioinspired octopus-mimicking adhesive. A resistor-type temperature sensor consisting of a composite of poly(N-isopropylacrylamide) (pNIPAM)-temperature sensitive hydrogel, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate, and carbon nanotubes exhibits a very high thermal sensitivity of 2.6%·°C-1 between 25 and 40 °C so that the change in skin temperature of 0.5 °C can be accurately detected. At the same time, the polydimethylsiloxane adhesive layer of octopus-mimicking rim structure coated with pNIPAM is fabricated through the formation of a single mold by utilizing undercut phenomenon in photolithography. The fabricated sensor shows stable and reproducible detection of skin temperature under repeated attachment/detachment cycles onto skin without any skin irritation for a long time. This work suggests a high potential application of our skin-attachable temperature sensor to wearable devices for medical and health-care monitoring.