A H2O2 Oxidation Approach to Ti3C2/TiO2 for Efficient Photocatalytic Removal of Distinct Organic Pollutants in Water.

To develop versatile photocatalysts for efficient degradation of distinct organic pollutants in water is a continuous pursuit in environment remediation. Herein, we directly oxidize Ti3C2 MXene with hydrogen peroxide to produce C-doped anatase TiO2 nanowires with aggregates maintaining a layered architecture of the MXene. The Ti3C2 MXene provides a titanium source for TiO2, a carbon source for in situ C-doping, and templates for nanowire aggregates. Under UV light illumination, the optimized Ti3C2/TiO2 exhibits a reaction rate constant 1.5 times that of the benchmark P25 TiO2 nanoparticles, toward photocatalytic degradations of trace phenol in water. The mechanism study suggests that photogenerated holes play key roles on the phenol degradation, either directly oxidizing phenol molecules or in an indirect way through oxidizing first the surface hydroxyl groups. The unreacted Ti3C2 MXene, although with trace amounts, is supposed to facilitate electron transfer, which inhibits charge recombination. The unique nanostructure of layered aggregates of nanowires, abundant surface oxygen vacancies arising from the carbon doping, and probably the Ti3C2/TiO2 heterojunction guarantee the high photocatalytic efficiency toward removals of organic pollutants in water. The photocatalyst also exhibits an activity superior to, or at least comparable to, the benchmark P25 TiO2 toward photodegradations for typical persistent organic pollutants of phenol, dye molecule of rhodamine B, antibiotic of tetracycline, pharmaceutical wastewater of ofloxacin, and pesticide of N,N-dimethylformamide, when evaluated in total organic carbon removal.

Perovskite Single Crystals with Self-Cleaning Surface for Efficient Photovoltaics.

Metal halide perovskite single crystals are promising for diverse optoelectronic applications. As a universal issue of solution-grown perovskite single crystals, surface contamination causes adverse effect on material properties and device performance. Herein, learning from the self-cleaning effect of lotus leaf, we address the surface contamination issue by introducing an amphiphilic long-chain organic amine into the perovskite crystal growth solution. Self-assembly of CTAC provides a hydrophobic crystal surface, inducing spontaneous removal of residual growth solution, which results in clean surface and better optoelectronic properties of perovskite single crystals. An impressive efficiency of 23.4 % is obtained, setting a new record for FAx MA1-x PbI3 single-crystal perovskite solar cells (PSCs). Moreover, our strategy also applies to perovskite single crystals with different morphology and composition, which may contribute to improvement of other single-crystal perovskite optoelectronic devices.

Oligomer Dynamics of LL-37 Truncated Fragments Probed by α-Hemolysin Pore and Molecular Simulations.

Oligomerization of antimicrobial peptides (AMPs) is critical in their effects on pathogens. LL-37 and its truncated fragments are widely investigated regarding their structures, antimicrobial activities, and application, such as developing new antibiotics. Due to the small size and weak intermolecular interactions of LL-37 fragments, it is still elusive to establish the relationship between oligomeric states and antimicrobial activities. Here, an α-hemolysin nanopore, mass spectrometry (MS), and molecular dynamic (MD) simulations are used to characterize the oligomeric states of two LL-37 fragments. Nanopore studies provide evidence of trapping events related to the oligomer formation and provide further details on their stabilities, which are confirmed by MS and MD simulations. Furthermore, simulation results reveal the molecular basis of oligomer dynamics and states of LL-37 fragments. This work provides unique insights into the relationship between the oligomer dynamics of AMPs and their antimicrobial activities at the single-molecule level. The study demonstrates how integrating methods allows deciphering single molecule level understanding from nanopore sensing approaches.

Novel Non-duct-to-Mucosa Pancreaticojejunostomy Reconstruction After Pancreaticoduodenectomy: Focus on the Occurrence of Post-pancreatectomy Hemorrhage and Intra-abdominal Abscess.

BACKGROUND: Postoperative pancreatic fistulas (POPFs) are considered inevitable in some patients after pancreaticoduodenectomy (PD), and measures to minimize their clinical impact are needed. Postpancreatectomy hemorrhage (PPH) and intra-abdominal abscess (IAA) are the most severe POPF-related complications, and concomitant leakage of contaminated intestinal content is considered the main cause. An innovative method, modified non-duct-to-mucosa pancreaticojejunostomy (TPJ), was created to prevent concomitant leakage of intestinal content, and its effectiveness was compared between two periods. METHODS: All PD patients undergoing pancreaticojejunostomy from 2012 to 2021 were included. The TPJ group consisted of 529 patients recruited from January 2018 to December 2021. A total of 535 patients receiving the conventional method (CPJ) from January 2012 to June 2017 were used as a control group. PPH and POPF were defined according to the International Study Group of Pancreatic Surgery definition, but only PPH grade C was included for analysis. An IAA was defined as a collection of postoperative fluid managed by CT-guided drainage with documental culture. RESULTS: There were no significant differences in the rate of POPF between the two groups (46.0% vs. 44.8%; p = 0.700). Furthermore, the percentages of bile in the drainage fluid in the TPJ and CPJ groups were 2.3% and 9.2%, respectively (p < 0.001). Lower proportions of PPH (0.9% vs. 6.5%; p < 0.001) and IAA (5.7% vs. 10.8%; p < 0.001) were observed for TPJ than for CPJ. On adjusted models, TPJ was significantly associated with a lower rate of PPH (odds ratio [OR] 0.132, 95% confidence interval [CI] 0.051-0.343; p < 0.001) and IAA (OR 0.514, 95% CI 0.349-0.758; p = 0.001) than CPJ. CONCLUSIONS: TPJ is feasible to be performed and is associated with a similar rate of POPF but a lower percentage of concomitant bile in the drainage fluid and subsequent rates of PPH and IAA than CPJ.

The utility of Vision Transformer in preoperatively predicting microvascular invasion status of hepatocellular carcinoma.

BACKGROUND: Microvascular invasion (MVI) is a risk factor for early recurrence and poor prognosis of hepatocellular carcinoma (HCC). Preoperative assessment of MVI status is beneficial for clinical therapy and prognosis evaluation. METHODS: A total of 305 surgically resected patients were included retrospectively. All recruited patients underwent plain and contrast-enhanced abdominal CT. They were then randomly divided into training and validation sets in a ratio of 8:2. Self-attention-based ViT-B/16 and ResNet-50 analyzed CT images to predict MVI status preoperatively. Then, Grad-CAM was used to generate an attention map showing the high-risk MVI patches. Using five-fold cross validation, the performance of each model was evaluated. RESULTS: Among 305 HCC patients, 99 patients were pathologically MVI-positive and 206 were MVI-negative. ViT-B/16 with fusion phase predicted the MVI status with an AUC of 0.882 and an accuracy of 86.8% in the validation set, which is similar to ResNet-50 with an AUC of 0.875 and an accuracy of 87.2%. The fusion phase improved performance a bit as compared to the single phase used for MVI prediction. The influence of peritumoral tissue on predictive ability was limited. A color visualization of the suspicious patches where microvascular has invaded was presented by attention maps. CONCLUSION: ViT-B/16 model can predict preoperative MVI status in CT images of HCC patients. Assisted by attention maps, it can assist patients in making tailored treatment decisions.

High-Performance and Self-Powered X-Ray Detectors Made of Smooth Perovskite Microcrystalline Films with 100†µm Grains.

Perovskite single crystals and polycrystalline films have complementary merits and deficiencies in X-ray detection and imaging. Herein, we report preparation of dense and smooth perovskite microcrystalline films with both merits of single crystals and polycrystalline films through polycrystal-induced growth and hot-pressing treatment (HPT). Utilizing polycrystalline films as seeds, multi-inch-sized microcrystalline films can be in situ grown on diverse substrates with maximum grain size reaching 100 µm, which endows the microcrystalline films with comparable carrier mobility-lifetime (µτ) product as single crystals. As a result, self-powered X-ray detectors with impressive sensitivity of 6.1×104  µC Gyair -1 cm-2 and low detection limit of 1.5 nGyair s-1 are achieved, leading to high-contrast X-ray imaging at an ultra-low dose rate of 67 nGyair s-1 . Combining with the fast response speed (186 µs), this work may contribute to the development of perovskite-based low-dose X-ray imaging.

Single-molecule studies of amyloid proteins: from biophysical properties to diagnostic perspectives.

In neurodegenerative diseases, a wide range of amyloid proteins or peptides such as amyloid-beta and α-synuclein fail to keep native functional conformations, followed by misfolding and self-assembling into a diverse array of aggregates. The aggregates further exert toxicity leading to the dysfunction, degeneration and loss of cells in the affected organs. Due to the disordered structure of the amyloid proteins, endogenous molecules, such as lipids, are prone to interact with amyloid proteins at a low concentration and influence amyloid cytotoxicity. The heterogeneity of amyloid proteinscomplicates the understanding of the amyloid cytotoxicity when relying only on conventional bulk and ensemble techniques. As complementary tools, single-molecule techniques (SMTs) provide novel insights into the different subpopulations of a heterogeneous amyloid mixture as well as the cytotoxicity, in particular as involved in lipid membranes. This review focuses on the recent advances of a series of SMTs, including single-molecule fluorescence imaging, single-molecule force spectroscopy and single-nanopore electrical recording, for the understanding of the amyloid molecular mechanism. The working principles, benefits and limitations of each technique are discussed and compared in amyloid protein related studies.. We also discuss why SMTs show great potential and are worthy of further investigation with feasibility studies as diagnostic tools of neurodegenerative diseases and which limitations are to be addressed.

The American Paddlefish Genome Provides Novel Insights into Chromosomal Evolution and Bone Mineralization in Early Vertebrates.

Sturgeons and paddlefishes (Acipenseriformes) occupy the basal position of ray-finned fishes, although they have cartilaginous skeletons as in Chondrichthyes. This evolutionary status and their morphological specializations make them a research focus, but their complex genomes (polyploidy and the presence of microchromosomes) bring obstacles and challenges to molecular studies. Here, we generated the first high-quality genome assembly of the American paddlefish (Polyodon spathula) at a chromosome level. Comparative genomic analyses revealed a recent species-specific whole-genome duplication event, and extensive chromosomal changes, including head-to-head fusions of pairs of intact, large ancestral chromosomes within the paddlefish. We also provide an overview of the paddlefish SCPP (secretory calcium-binding phosphoprotein) repertoire that is responsible for tissue mineralization, demonstrating that the earliest flourishing of SCPP members occurred at least before the split between Acipenseriformes and teleosts. In summary, this genome assembly provides a genetic resource for understanding chromosomal evolution in polyploid nonteleost fishes and bone mineralization in early vertebrates.

Kilowatt random Raman fiber laser with full-open cavity.

Random Raman fiber laser (RRFL) has been widely studied in high-power laser generation due to its special lasing characteristics. However, all previous high-power results are based on the half-open cavity. In this letter, we demonstrate an applicable high-power RRFL with the simplest structure, that is, a full-open cavity. The lasing dynamic and output characteristics are theoretically and experimentally studied. Laser source with multi-longitudinal modes can result in the random laser output from one side even in the full-open cavity. The ratio of the backward output power is mainly determined by the reflectivity of fiber ends. The experimental results show that such a simple structure can easily generate kilowatts of random laser power and is a promising setup to achieve higher output power, which is also an important platform to study the laser dynamic in high-power full-open cavity without any point-action or regular distributed reflectors.

Wide temperature operation of kilowatt fiber oscillators.

To meet the requirements of fiber laser applications under extreme temperatures or when there is a large temperature difference, it is necessary to develop fiber lasers able to operate in a wide temperature range. At present, there is a lack of reports on high-power fiber lasers that can operate in a wide temperature range with low power fluctuations. Thus, we designed a 1 kW fiber oscillator that can operate in a wide temperature range through temperature-related rate equations. The output characteristics of the oscillator are measured in the operating temperature range from -30∘C to 20°C. The experimental results show that the laser output power fluctuates by 7% over the entire temperature range. It was discovered that as the ambient temperature decreased, the efficiency of the laser decreased, and this issue is discussed in detail. This work has guiding significance for the design of high-power fiber lasers operating at a wide temperature range, and simultaneously, to the best of our knowledge, it provides the first kilowatt fiber oscillator that can operate in a wide temperature range between -30∘C and 20°C.

Surface-Induced Desolvation of Hydronium Ion Enables Anatase TiO2 as an Efficient Anode for Proton Batteries.

Hydrogen ion is an attractive charge carrier for energy storage due to its smallest radius. However, hydrogen ions usually exist in the form of hydronium ion (H3O+) because of its high dehydration energy; the choice of electrode materials is thus greatly limited to open frameworks and layered structures with large ionic channels. Here, the desolvation of H3O+ is achieved by using anatase TiO2 as anodes, enabling the H+ intercalation with a strain-free characteristic. Density functional theory calculations show that the desolvation effects are dependent on the facets of anatase TiO2. Anatase TiO2 (001) surface, a highly reactive surface, impels the desolvation of H3O+ into H+. When coupled with a MnO2 cathode, the proton battery delivers a high specific energy of 143.2 Wh/kg at an ultrahigh specific power of 47.9 kW/kg. The modulation of the interactions between ions and electrodes opens new perspectives for battery optimizations.

Chemical composition of smoke produced by open versus laparoscopic surgery for cholecystectomy.

BACKGROUND: Smoke produced by traditional open surgery (TOS) has long been considered hazardous to medical staff. Compared with TOS, minimally invasive surgery under carbon dioxide pneumoperitoneum is associated with a faster recovery and less wound pain. However, the impact of oxygen-deficient environment on the chemical contents of smoke has not been comprehensively assessed. METHODS: This research evaluated the chemical composition and volatile organic compound (TVOC) level in smoke produced by open cholecystectomy (OC) versus laparoscopic cholecystectomy (LC) for gallbladder diseases. Smoke samples were collected and analyzed via gas chromatography-mass spectrometry. Chemical compounds were further grouped according to molecular weight and toxicity. RESULTS: Compared with the OC, LC had significantly higher halocarbon and TVOC levels but lower cycloalkene and aldehyde levels. No halocarbons were isolated from OC specimens. When stratified based on molecular weight, LC had a bimodal pattern (i.e., high levels of small-sized [<60 Da] and large-sized [>120 Da] compounds). There was no difference in terms of toxicity types, incidence, and severity associated with detected compounds between two groups. CONCLUSION: LC is associated with a higher TVOC level and proportion of low- and high-molecular-weight organic compounds. Further strategies of evacuating these health hazards and preventing smoke leakage through trocars should be considered.

Branching TiO2nanowire arrays for enhanced ethanol sensing.

Nanostructure modulation is effective to achieve high performance TiO2-based gas sensors. We herein report a wet-chemistry route to precipitate directly branched TiO2nanowire arrays on alumina tubes for gas sensing applications. The optimized branched TiO2nanowire array exhibits a response of 9.2 towards 100 ppm ethanol; whilst those of the pristine TiO2nanowire array and the branched TiO2nanowire powders randomly distributed are 5.1 and 3.1, respectively. The enhanced response is mainly contributed to the unique porous architecture and quasi-aligned nanostructure, which provide more active sites and also favor gas migration. Phase junctions between the backbone and the branch of the branched TiO2nanowire arrays help the resistance modulation as a result of potential barriers. The facile precipitation of quasi-aligned arrays of branched TiO2nanowires, which arein situgrown on ceramic tubes, thus provides a new economical synthetic route to TiO2-based sensors with excellent properties.

Effects of dyslipidemia on E antigen seroconversion of patients with chronic hepatitis B treated by nucleoside (acid) analogs.

BACKGROUND: The prevalence of dyslipidemia in China is increasing annually. Current studies suggest that dyslipidemia affects the antiviral efficacy of hepatitis C virus (HCV) therapies, while recent studies suggest that serum lipids influence the response rates of chronic hepatitis B (CHB) patients receiving PEGylated interferon-alpha (Peg IFN-α) treatment. However, the role of dyslipidemia in the efficacy of nucleoside (acid) analogues (NAs) in CHB patients remains unclear. METHODS: From January 2010 to December 2013, data from 179 treatment-naive patients with CHB who were hepatitis B e antigen (HBeAg)-positive and had visited the first affiliated hospital of Wenzhou Medical University were assessed. Of these patients, 68 were assigned to the dyslipidemia group (diagnosed with CHB complicated with dyslipidemia) and 111 to the normolipidemic group. The following 3 treatment strategies were performed for all CHB patients over a 5-year period: lamivudine (LAM) plus adefovir dipivoxil (ADV) combination therapy, telbivudine (LdT) monotherapy, and entecavir (ETV) monotherapy. Serum assessments, blood biochemistry, HBV serological markers, HBV DNA before treatment and HBeAg serological conversion and virological responses at different timepoints after treatment were compared between the two groups. Measurement data were compared by τ tests and enumeration data by χ2 tests. Correlation analysis was performed using binary logistic regression analysis. RESULTS: The rates of HBeAg seroconversion in the dyslipidemia group at years 1, 2, 3, and 4 were 10.3, 13.2, 17.6, and 22.1%, respectively, which were not significantly lower than those of the normolipidemic group (11.7, 16.2, 18.0 and 33.3%; χ2 = 0.085, 0.293, 0.004, and 2.601, respectively; Ρ > 0.05). However, the rates of HBeAg seroconversion in the dyslipidemia group were significantly lower than those in the normolipidemic group at year 5 (27.9% vs. 43.2%, χ2 = 4.216, Ρ < 0.05). Univariate logistic regression analysis revealed significant differences in group, gender, PTA, ALT, AST, CR, and LDL-C between groups with and without seroconversion. Multivariate regression analysis demonstrated that dyslipidemia (OR = 1.993, Ρ = 0.038) and male gender (OR = 2.317, Ρ = 0.029) were risk factors associated with HBeAg seroconversion. CONCLUSIONS: During antiviral therapy, dyslipidemia affects HBeAg seroconversion in CHB patients treated with NAs, but does not affect the virological response.

Protective Effects of Glutamine and Leucine Supplementation on Sepsis-Induced Skeletal Muscle Injuries.

This study investigated the effects of l-glutamine (Gln) and/or l-leucine (Leu) administration on sepsis-induced skeletal muscle injuries. C57BL/6J mice were subjected to cecal ligation and puncture to induce polymicrobial sepsis and then given an intraperitoneal injection of Gln, Leu, or Gln plus Leu beginning at 1 h after the operation with re-injections every 24 h. All mice were sacrificed on either day 1 or day 4 after the operation. Blood and muscles were collected for analysis of inflammation and oxidative damage-related biomolecules. Results indicated that both Gln and Leu supplementation alleviated sepsis-induced skeletal muscle damage by reducing monocyte infiltration, calpain activity, and mRNA expression levels of inflammatory cytokines and hypoxia-inducible factor-1α. Furthermore, septic mice treated with Gln had higher percentages of blood anti-inflammatory monocytes and muscle M2 macrophages, whereas Leu treatment enhanced the muscle expressions of mitochondrion-related genes. However, there were no synergistic effects when Gln and Leu were simultaneously administered. These findings suggest that both Gln and Leu had prominent abilities to attenuate inflammation and degradation of skeletal muscles in the early and/or late phases of sepsis. Moreover, Gln promoted the switch of leukocytes toward an anti-inflammatory phenotype, while Leu treatment maintained muscle bioenergetic function.

Pancreatic neck transection using a harmonic scalpel increases risk of biochemical leak but not postoperative pancreatic fistula after pancreaticoduodenectomy.

BACKGROUND: The effect of a harmonic scalpel on postoperative pancreatic fistula (POPF) has not been addressed. This study assessed the effect of pancreatic neck transection using a harmonic scalpel on rate and severity of POPF after pancreaticoduodenectomy (PD). METHODS: This retrospective analysis included patients who underwent PD at National Taiwan University Hospital between July 2015 and March 2019. We compared rate and severity of POPF between patients who underwent pancreatic neck transection using a harmonic scalpel versus electrosurgical unit. RESULTS: Of 422 consecutive PDs, the pancreatic neck was transected using a harmonic scalpel or electrosurgical unit in 144 and 278 patients, respectively. Use of a harmonic scalpel significantly increased risk of biochemical leak (25.7% versus [vs] 10.8%; P < 0.05) but not clinically relevant POPF (CR-POPF; 30.2% vs 26.4%; P = 0.41). Harmonic transection was an independent predictor of biochemical leak (odds ratio [OR] = 2.93; P < 0.05) but not CR-POPF (OR = 0.83; P = 0.41) or other major complications (OR = 0.72; P = 0.27). There was no significant intergroup difference in postoperative hospital stay. CONCLUSION: Pancreatic neck transection using a harmonic scalpel increased risk of biochemical leak but not CR-POPF or other major complications.

Cryo-electron Microscopy Imaging of Alzheimer's Amyloid-beta 42 Oligomer Displayed on a Functionally and Structurally Relevant Scaffold.

Amyloid-ß peptide (Aß) oligomers are pathogenic species of amyloid aggregates in Alzheimer's disease. Like certain protein toxins, Aß oligomers permeabilize cellular membranes, presumably through a pore formation mechanism. Owing to their structural and stoichiometric heterogeneity, the structure of these pores remains to be characterized. We studied a functional Aß42-pore equivalent, created by fusing Aß42 to the oligomerizing, soluble domain of the α-hemolysin (αHL) toxin. Our data reveal Aß42-αHL oligomers to share major structural, functional, and biological properties with wild-type Aß42-pores. Single-particle cryo-EM analysis of Aß42-αHL oligomers (with an overall 3.3 Šresolution) reveals the Aß42-pore region to be intrinsically flexible. The Aß42-αHL oligomers will allow many of the features of the wild-type amyloid oligomers to be studied that cannot be otherwise, and may be a highly specific antigen for the development of immuno-base diagnostics and therapies.

Molecular characterization, expression pattern and evolution of nine suppressors of cytokine signaling (SOCS) gene in the swamp eel (Monopterus albus).

Suppressors of cytokine signaling (SOCS) family members have negative effects on cytokine signaling pathways involved in immunity, growth and development. Owing to their typical feature, they have been extensively studied in mammalians, but they have not offered systematic studies among teleosts. In the present study, nine SOCS family genes were identified in the swamp eel genome and analyzed regulation mechanisms of SOCS family members in swamp eels. The open reading frames of MaSOCS1a, MaSOCS1b, MaSOCS2, MaSOCS3a, MaSOCS3b, MaSOCS4, MaSOCS5, MaSOCS6 and MaSOCS7 were 663 bp, 603 bp, 717 bp, 618 bp, 645 bp, 1188 bp, 1488 bp, 1611 bp and 1998 bp and encoded 220, 238, 200, 205, 214, 395, 496, 536 and 655 amino acids, respectively. All SOCS proteins have no signal peptides. Multiple alignment revealed that MaSOCS family members possessed a typical conserved SOCS box and SH2 region. Phylogenetic analyses showed that all SOCS proteins were divided into two main clusters. Taken together with the similarity and identity of SOCS protein amino acids, these results indicated that MaSOCS family members shared conserved with other homologous genes, in which MaSOCS7 was more conserved. Further syntenic analysis confirmed the phylogenetic analysis results and annotation of SOCS protein, suggesting that MaSOCS5 shared a common ancestor gene with that of fish and humans. MaSOCS family members were constitutively expressed in a wide range of tissues with different levels. In particular, spleen and head kidneys play an important role in immune-related pathways. After Aeromonas veronii and polyinosinic-polycytidylic acid (poly I:C) challenge in the spleen and head kidney, MaSOCS family members exhibit different expression profiles. These expression patterns indicated that MaSOCS family members could make acute responses after pathogen invasion. Taken together, these results indicate that MaSOCS family members participate in the immune response against pathogens and offer a solid foundation for future studies of SOCS function.

Facet-dependent decoration of TiO2 mesocrystals on TiO2 microcrystals for enhanced photoactivity.

Bottom-up constructions of hierarchical TiO2 are effective to enhance their photoactivity towards degradations of organic pollutants. Thanks to highly active facets, {001} exposed anatase TiO2 microcrystals attract much attention in photocatalysis; yet their efficiency is limited by the large crystal size. Herein, we report a facile solution approach to deposit anatase TiO2 mesocrystals only on {101} facets of anatase TiO2 microcrystals. The selective surface decoration enhances the photoactivity through replacing the less active {101} facets with more active TiO2 mesocrystals; whilst the highly active {001} facets remain untouched. When utilized to assist photodegradation of phenol in water under UV light illumination, the hierarchical TiO2 exhibited a reaction rate constant doubled that of the pristine {001} exposed TiO2 microcrystals. The present tactic to selectively decorate TiO2 microcrystals may give hints to other applications involving facet-dependent properties.

Enhanced isopropanol sensing of coral-like ZnO-ZrO2 composites.

Both p-type ZrO2 and n-type ZnO are widely adopted oxides towards trace gas detections; however, their combinations to achieve an enhanced gas sensing performance are rarely reported. Herein, we adopted a simple solution combustion technique to synthesize ZnO-ZrO2 composites for isopropanol sensing. The one-step combustion achieved coral-like macro/mesoporous hierarchical architectures. It is found that, when the Zr/Zn molar ratio is less than 0.02, all Zr atoms were doped into ZnO crystallites; whilst ZrO2 appeared when the ratio is beyond 0.03. When utilized to detect trace isopropanol in air, the response increases linearly with the increasing concentration of the target gas in the range of 10-1000 ppm. At the optimal operation temperature of 350 °C, the largest slope (0.18 ppm-1) is recorded for the ZnO-ZrO2 composite with a Zr/Zn molar ratio of 0.04 and the slope is 23 times that of pure ZnO (0.0078 ppm-1). It exhibits also a fast response time and recovery time of 19 s and 8 s, respectively, under 100 ppm isopropanol. The impressive gas sensing property can be contributed to both the macro-/mesoporous structure, which facilitates an intimate contact between the target gas and the sensing site, and the p-n junction induced built-in electric field, which favors the charge separation.