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1.
Anal Chem ; 96(1): 179-187, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38100653

RESUMO

Achieving accurate detection of different speciations of heavy metal ions (HMIs) in an aqueous solution is an urgent problem due to the different bioavailabilities and physiological toxicity. Herein, we nominated a novel strategy to detect HCrO4- and Cr(OH)2+ at a trace level via the electrochemical sensitive surface constructed by Co3O4-rGO modified with amino and carboxyl groups, which revealed that the interactions between distinct functional groups and different oxygen-containing groups of target ions are conducive to the susceptible and anti-interference detection. The detection sensitivities of 19.46 counts µg-1 L for HCrO4- and 13.44 counts µg-1 L for Cr(OH)2+ were obtained under optimal conditions, while the limits of detection were 0.10 and 0.12 µg L-1, respectively. Satisfactory anti-interference and actual water sample analysis results were obtained. A series of advanced optical techniques like X-ray photoelectron spectroscopy, X-ray absorption near-edge structure technology, and density functional theory calculations under an electric field demonstrated that chemical interactions between groups contribute more to the fixation of target ions than electrical attraction alone. The presence of oxygen-containing groups distinct from simple ionic forms was a critical factor in the selectivity and anti-interference detection. Furthermore, the valence cycle of Co(II)/(III) synergistically boosted the detection performance. This research provides a promising tactic from the microscopic perspective of groups' interactions to accomplish the precise speciation analysis of HMIs in the water environment.

2.
Anal Chem ; 96(13): 5232-5241, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38447030

RESUMO

Although utilizing nanomaterial-modified electrodes for lead ion detection has achieved great success, most of them are carried out under acidic conditions and ignore the variation of Pb(II) speciation at different pH conditions, leading to the potential inaccuracy of Pb(II) detection in a neutral natural water environment. Thus, designing a novel catalyst with high accuracy for the detection of various forms of the total amount of Pb(II) (Pb2+ and Pb(OH)+) in neutral waters is significant. Herein, Pt nanoclusters (Pt NCs) were elaborately constructed and stabilized on the Co single-atom-doped g-C3N4 with abundant N vacancies (Pt NCs/VN-C3N4), which achieved the ultrasensitive detection (102.16 µM µA-1) of Pb(II) in neutral conditions. The dynamic simulation and theoretical calculations reveal that the parallel deposition of Pb2+ and Pb(OH)+ occurs on the electrode surface modified by Pt NCs/VN-C3N4, and the current peaks of Pb(II) are cocontributed by Pb2+ and Pb(OH)+ species. An "electron inverse" phenomenon in Pt NCs/VN-C3N4 from the VN-C3N4 substrate to Pt NCs endows Pt NCs in an electron-rich state, serving as active centers to promote rapid and efficient reduction for both Pb2+ and Pb(OH)+, facilitating the accurate detection of the total amount of Pb(II) in all forms in the actual water environment.

3.
Anal Chem ; 96(22): 9069-9077, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38749062

RESUMO

Solid contact (SC) calcium ion-selective electrodes (Ca2+-ISEs) have been widely applied in the analysis of water quality and body fluids by virtue of the unique advantages of easy operation and rapid response. However, the potential drift during the long-term stability test hinders their further practical applications. Designing novel redox SC layers with large capacitance and high hydrophobicity is a promising approach to stabilize the potential stability, meanwhile, exploring the transduction mechanism is also of great guiding significance for the precise design of SC layer materials. Herein, flower-like copper sulfide (CunS-50) composed of nanosheets is meticulously designed as the redox SC layer by modification with the surfactant (CTAB). The CunS-50-based Ca2+-ISE (CunS-50/Ca2+-ISE) demonstrates a near-Nernstian slope of 28.23 mV/dec for Ca2+ in a wide activity linear range of 10-7 to 10-1 M, with a low detection limit of 3.16 × 10-8 M. CunS-50/Ca2+-ISE possesses an extremely low potential drift of only 1.23 ± 0.13 µV/h in the long-term potential stability test. Notably, X-ray absorption fine-structure (XAFS) spectra and electrochemical experiments are adopted to elucidate the transduction mechanism that the lipophilic anion (TFPB-) participates in the redox reaction of CunS-50 at the solid-solid interface of ion-selective membrane (ISM) and redox inorganic SC layer (CunS-50), thereby promoting the generation of free electrons to accelerate ion-electron transduction. This work provides an in-depth comprehension of the transduction mechanism of the potentiometric response and an effective strategy for designing redox materials of ion-electron transduction triggered by lipophilic anions.

4.
World J Surg ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38964867

RESUMO

PURPOSE: It is well established that hollow viscus perforation leads to sepsis and acute kidney injury (AKI) in non-trauma patients. However, the relationship between traumatic hollow viscus injury (HVI) and AKI is not well understood. Utilizing data from the National Trauma Data Bank, we investigated whether HVI serves as a risk factor for AKI. Additionally, we examined the characteristics of AKI in stable patients who underwent conservative treatment. METHODS: We reviewed blunt abdominal trauma (BAT) cases from 2012 to 2015, comparing patients with and without AKI. Significant factors from univariate analysis were tested in a multivariate logistic regression (MLR) to identify independent AKI determinants. We also analyzed subsets: patients without HVI and stable patients given conservative management. RESULTS: Out of the 563,040 BAT patients analyzed, 9073 (1.6%) developed AKI. While a greater proportion of AKI patients had HVI than those without AKI (13.3% vs. 5.2%, p < 0.001), this difference wasn't statistically significant in the MLR (p = 0.125). Notably, the need for laparotomy (odds = 3.108, p < 0.001) and sepsis (odds = 13.220, p < 0.001) were identified as independent risk factors for AKI. For BAT patients managed conservatively (systolic blood pressure >90 mmHg, without HVI or laparotomy; N = 497,066), the presence of sepsis was a significant predictor for the development of AKI (odds = 16.914, p < 0.001). CONCLUSIONS: While HVI wasn't a significant risk factor for AKI in BAT patients, the need for laparotomy was. Stable BAT patients managed conservatively are still at risk for AKI due to non-peritonitis related sepsis.

5.
Ann Plast Surg ; 92(1S Suppl 1): S27-S32, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38285992

RESUMO

BACKGROUND: Patients with traumatic brain injuries (TBIs) often experience concurrent facial bone fractures. In 2021, a prediction model with 10 variables was published and precisely predicted concomitant facial fractures in TBI patients. Herein, external validation and simplification of this model was performed. METHODS: Traumatic brain injury patients treated at a major referral trauma center were retrospectively reviewed for 1 year. The original prediction model (published in 2021), which was developed from a rural level II trauma center, was applied for external validation. A new and simplified model from our level I trauma center was developed and backwardly validated by rural level II trauma center data. RESULTS: In total, 313 TBI patients were enrolled; 101 (32.3%) had concomitant facial fractures. When the previous prediction model was applied to the validation cohort, it achieved acceptable discrimination, with an area under the receiver operating characteristic curve (AUC) of 0.713 and good precision, with a Brier score of 0.083. A new and simplified model with 6 variables (age, tooth rupture, epistaxis, facial lesion, eye injury, and intracranial hemorrhage) was created with excellent discrimination (AUC = 0.836) and good precision (Brier score of 0.055). The backward validation of this new model also showed excellent discrimination in the cohort used to develop the original model (AUC = 0.875). CONCLUSION: The original model provides an acceptable and reproducible prediction of concomitant facial fractures among TBI patients. A simplified model with fewer variables and the same accuracy could be applied in the emergency department and at higher- and lower-level trauma centers.


Assuntos
Lesões Encefálicas Traumáticas , Fraturas Cranianas , Humanos , Estudos Retrospectivos , Fraturas Cranianas/complicações , Fraturas Cranianas/diagnóstico , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico , Curva ROC , Centros de Traumatologia
6.
Anal Chem ; 95(7): 3666-3674, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36656141

RESUMO

Traditional nanomodified electrodes have made great achievements in electrochemical stripping voltammetry of sensing materials for As(III) detection. Moreover, the intermediate states are complicated to probe because of the ultrashort lifetime and complex reaction conditions of the electron transfer process in electroanalysis, which seriously hinder the identification of the actual active site. Herein, the intrinsic interaction of highly sensitive analytical behavior of nanomaterials is elucidated from the perspective of electronic structure through density functional theory (DFT) and gradient boosting regression (GBR). It is revealed that the atomic radius, d-band center (εd), and the largest coordinative TM-N bond length play a crucial role in regulating the arsenic reduction reaction (ARR) performance by the established ARR process for 27 sets of transition-metal single atoms supported on N-doped graphene. Furthermore, the database composed of filtered intrinsic electronic structural properties and the calculated descriptors of the central metal atom in TM-N4-Gra were also successfully extended to oxygen evolution reaction (OER) systems, which effectively verified the reliability of the whole approach. Generally, a multistep workflow is developed through GBR models combined with DFT for valid screening of sensing materials, which will effectively upgrade the traditional trial-and-error mode for electrochemical interface designing.

7.
Anal Chem ; 95(8): 4104-4112, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36688529

RESUMO

Significant progress has been made in nanomaterial-modified electrodes for highly efficient electroanalysis of arsenic(III) (As(III)). However, the modifiers prepared using some physical methods may easily fall off, and active sites are not uniform, causing the potential instability of the modified electrode. This work first reports a promising practical strategy without any modifiers via utilizing only soluble Fe3+ as a trigger to detect trace-level As(III) in natural water. This method reaches an actual detection limit of 1 ppb on bare glassy carbon electrodes and a sensitivity of 0.296 µA ppb-1 with excellent stability. Kinetic simulations and experimental evidence confirm the codeposition mechanism that Fe3+ is preferentially deposited as Fe0, which are active sites to adsorb As(III) and H+ on the electrode surface. This facilitates the formation of AsH3, which could further react with Fe2+ to produce more As0 and Fe0. Meanwhile, the produced Fe0 can also accelerate the efficient enrichment of As0. Remarkably, the proposed sensing mechanism is a general rule for the electroanalysis of As(III) that is triggered by iron group ions (Fe2+, Fe3+, Co2+, and Ni2+). The interference analysis of coexisting ions (Cu2+, Zn2+, Al3+, Hg2+, Cd2+, Pb2+, SO42-, NO3-, Cl-, and F-) indicates that only Cu2+, Pb2+, and F- showed inhibitory effects on As(III) due to the competition of active sites. Surprisingly, adding iron power effectively eliminates the interference of Cu2+ in natural water, achieving a higher sensitivity for 1-15 ppb As(III) (0.487 µA ppb-1). This study provides effective solutions to overcome the potential instability of modified electrodes and offers a practical sensing platform for analyzing other heavy-metal anions.

8.
World J Surg ; 47(12): 3116-3123, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37851065

RESUMO

PURPOSE: This study aimed to validate the previously reported association between delayed bladder repair and increased infection rates using the National Trauma Data Bank (NTDB). METHODS: Bladder injury patients with bladder repair in the NTDB from 2013 to 2015 were included. Propensity score matching (PSM) was used to compare mortality, infection rates, and hospital length of stay (LOS) between patients who underwent bladder repair within 24 h and those who underwent repair after 24 h. Linear regression and multivariate logistic regression analyses were also performed. RESULTS: A total of 1658 patients were included in the study. Patients who underwent bladder repair after 24 h had significantly higher infection rates (5.4% vs. 1.2%, p = 0.032) and longer hospital LOS (17.1 vs. 14.0 days, p = 0.032) compared to those who underwent repair within 24 h after a well-balanced 1:1 PSM (N = 166). Linear regression analysis showed a positive correlation between time to bladder repair and hospital LOS for patients who underwent repair after 24 h (B-value = 0.093, p = 0.034). Multivariate logistic regression analysis indicated that bladder repair after 24 h increased the risk of infection (odds = 3.162, p = 0.018). Subset analyses were performed on patients who underwent bladder repairs within 24 h and were used as a control group. These analyses showed that the time to bladder repair did not significantly worsen outcomes. CONCLUSIONS: Delayed bladder repair beyond 24 h increases the risk of infection and prolongs hospital stays. Timely diagnosis and surgical intervention remain crucial for minimizing complications in bladder injury patients.


Assuntos
Traumatismos Abdominais , Traumatismos Torácicos , Humanos , Bexiga Urinária/cirurgia , Tempo de Internação , Procedimentos Cirúrgicos Urológicos , Resultado do Tratamento , Estudos Retrospectivos
9.
Anal Chem ; 94(7): 3211-3218, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35104121

RESUMO

Vacancy and doping engineering are promising pathways to improve the electrocatalytic ability of nanomaterials for detecting heavy metal ions. However, the effects of the electronic structure and the local coordination on the catalytic performance are still ambiguous. Herein, cubic selenium vacancy-rich CoSe2 (c-CoSe2-x) and P-doped orthorhombic CoSe2-x (o-CoSe2-x|P) were designed via vacancy and doping engineering. An o-CoSe2-x|P-modified glass carbon electrode (o-CoSe2-x|P/GCE) acquired a high sensitivity of 1.11 µA ppb-1 toward As(III), which is about 40 times higher than that of c-CoSe2-x, outperforming most of the reported nanomaterial-modified glass carbon electrodes. Besides, o-CoSe2-x|P/GCE displayed good selectivity toward As(III) compared with other divalent heavy metal cations, which also exhibited excellent stability, repeatability, and practicality. X-ray absorption fine structure spectroscopy and density functional theory calculation demonstrate that electrons transferred from Co and Se to P sites through Co-P and Se-P bonds in o-CoSe2-x|P. P sites obtained plentiful electrons to form active centers, which also had a strong orbital coupling with As(III). In the detection process, As(III) was bonded with P and reduced by the electron-rich sites in o-CoSe2-x|P, thus acquiring a reinforced electrochemical sensitivity. This work provides an in-depth understanding of the influence of the intrinsic physicochemical properties of sensitive materials on the behavior of electroanalysis, thus offering a direct guideline for creating active sites on sensing interfaces.


Assuntos
Eletrônica , Elétrons , Teoria da Densidade Funcional , Espectroscopia por Absorção de Raios X , Raios X
10.
Anal Chem ; 94(16): 6225-6233, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35404584

RESUMO

Interference among multiple heavy metal ions (HMIs) is a significant problem that must be solved in electroanalysis, which extremely restricts the practical popularization of electrochemical sensors. However, due to the limited exploration of the intrinsic mechanism, it is still difficult to confirm the influencing factors. In this work, a series of experimental and theoretical electroanalysis models have been established to investigate the electroanalysis results of Cu(II), Cd(II), As(III), and their mixtures, which were based on the simple structure and stable coordination of nickel single-atom catalysts. X-ray absorption spectroscopy and density functional theory calculations were used to reveal the underlying detection mechanism of the 50-fold boosting effect of Cu(II) on As(III) while Cd(II) inhibits As(III). Combining the application of the thermodynamic model and Fourier transform infrared reflection, the specific interaction of the nanomaterials and HMIs on the interface is considered to be the fundamental source of the interference. This work opens up a new way of thinking about utilizing the unique modes of interplay between nanomaterials and HMIs to achieve anti-interference intelligent electrodes in stripping analysis.


Assuntos
Metais Pesados , Materiais Inteligentes , Cádmio/química , Íons , Metais Pesados/química , Termodinâmica
11.
Anal Chem ; 94(40): 13631-13641, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36150119

RESUMO

Constructing high-effective electrode sensing interfaces has been considered an effective method for electrochemical detection toward heavy metal ions (HMIs). However, most research has been devoted to enhancing the stripping currents of HMIs by simply improving the adsorptive capacity and conductivity of the electrode modified materials, while lacking theoretical guidelines in fabricating catalytic sensing interfaces. Besides, the understanding of detection mechanisms is quite unscientific from the perspective of catalysis. This perspective summarizes five general strategies in designing highly efficient sensing interfaces in the recent five years, including modulating crystal phases, orientations and planes, defect engineering, ionic valence state cycle engineering, adsorption in situ catalysis strategy, and construction of atomic level catalytic active sites. What's more, the catalytic mechanisms for improving the signals of HMIs, such as boosting the electron transfer rates and conversion rates, lowering the energy barriers, etc., are introduced and emphasized. This study has a great significance in directionally controlling functionalized electrochemical sensors to achieve excellent sensitivity and selectivity in detecting environmental pollutants from the view of catalysis, and it also brings enlightenments and guidance to develop new electroanalytical methods.


Assuntos
Poluentes Ambientais , Metais Pesados , Catálise , Eletrodos , Íons/química , Metais Pesados/química
12.
Anal Chem ; 93(45): 15115-15123, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34714618

RESUMO

Designing new catalysts with high activity and stability is crucial for the effective analysis of environmental pollutants under mild conditions. Here, we developed a superior catalyst of Pt single atoms anchored on MoS2 (Pt1/MoS2) to catalyze the determination of As(III). A detection sensitivity of 3.31 µA ppb-1 was obtained in acetate buffer solution at pH 6.0, which is the highest compared with those obtained by other Pt-based nanomaterials currently reported. Pt1/MoS2 exhibited excellent electrochemical stability during the detection process of As(III), even in the coexistence of Cu(II), Pb(II), and Hg(II). X-ray absorption fine structure spectroscopy and theoretical calculations revealed that Pt single atoms were stably fixed by four S atoms and activated the adjacent S atoms. Then, Pt and S atoms synergistically interacted with O and As atoms, respectively, and transferred some electrons to H3AsO3, which change the rate-determining step of H3AsO3 reduction and reduce reaction energy barriers, thereby promoting rapid and efficient accumulation for As(0). Compared with Pt nanoparticles, the weaker interaction between arsenic species and Pt1/MoS2 enabled the effortless regeneration and cyclic utilization of active centers, which is more favorable for the oxidation of As(0). This work provides inspiration for developing highly efficient sensing platforms from the perspective of atomic-level catalysis and affords references to explore the detection mechanism of such contaminants.


Assuntos
Arsenicais , Nanoestruturas , Arsenicais/química , Catálise , Molibdênio , Oxirredução , Platina
13.
Anal Chem ; 93(41): 14014-14023, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34607426

RESUMO

An atomic-level Au nanocluster, as an excellent photocatalyst, is generally not considered as an efficient electrocatalyst due to its poor stability. Herein, a method is proposed to stabilize abundant Au25 on Fe2O3 nanoplates (Au25/OV-Fe2O3) successfully with oxygen vacancies (OV) created. Au25/OV-Fe2O3 shows superhigh catalysis in the electrochemical reduction toward As(III). The record-breaking sensitivity (161.42 µA ppb-1) is two orders of magnitude higher than currently reported, where an ultratrace limit of detection (9 ppt) is obtained, suggesting promising applications in the analysis of organic and bioactive substances. The stability of Au25 is attributed to the Au-Fe bond formed after loading Au25 nanoclusters on Fe2O3 nanoplates through "electron compensation" and bond length (Au-S) shortening. Moreover, the ligand S atoms in Au25 nanoclusters significantly contribute to the reduction of As(III). The fantastic stability and superior catalytic ability of Au25/OV-Fe2O3 provide guidelines to stabilize Au nanoclusters on metal oxides, indicating their potential electroanalytical applications.


Assuntos
Ouro , Oxigênio , Catálise , Ligantes
14.
Anal Chem ; 92(24): 16089-16096, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33166462

RESUMO

Modulating the active sites of oxygen vacancies (OVs) to enhance the catalytic properties of nanomaterials has attracted much research interest in various fields, but its intrinsic catalytic mechanism is always neglected. Herein, we establish an efficient strategy to promote the electrochemical detection of Pb(II) by regulating the concentration of OVs in α-MoO3 nanorods via doping Ce3+/Ce4+ ions. α-MoO3 with the Ce-doped content of 9% (C9M) exhibited the highest detection sensitivity of 106.64 µM µA-1 for Pb(II), which is higher than that achieved by other metal oxides and most precious metal nanomaterials. It is found that C9M possessed the highest concentration of OVs, which trapped some electrons for strong affinity interaction with Pb(II) and provided numerous atomic level interfaces of high surface free energy for catalysis reactions. X-ray absorption fine structure spectra and density functional theory calculation indicate that Pb(II) was bonded with the surface-activated oxygen atoms (Os) around Ce ions and obtained some electrons from Os. Besides, the longer Pb-O bonds on C9M were easier to break, causing a low desorption energy barrier to effectively accelerate Pb(II) desorbing to the electrode surface. This study helps to understand the changes in electronic structure and catalytic performance with heteroatom doping and OVs in chemically inert oxides and provide a reference for designing high-active electrocatalytic interfaces to realize ultrasensitive analysis of environmental contaminants.

15.
Anal Chem ; 92(8): 6128-6135, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32207296

RESUMO

Achieving highly sensitive and selective detection of trace-level As(III) and clarifying the underlying mechanism is still a intractable problem. The electroanalysis of As(III) relies on the electrocatalytic ability of the sensing interface. Herein, we first adopt single-atom catalysts as the electrocatalyst in As(III) detection. Cobalt single-atoms anchored on nitrogen-doped carbon material (Co SAC) were found to have an extraordinary sensitivity of 11.44 µA ppb-1 with excellent stability and repeatability, which so far is the highest among non-noble metal nanomaterials. Co SAC also exhibited a superior selectivity toward As(III) compared with some bivalent heavy metal ions (HMIs). Combining X-ray absorption spectroscopy (XAFS), density functional theory (DFT) calculation, and reaction kinetics simulation, we demonstrated that Co single atoms stabilized in N2C2 support serve as active sites to catalyze H3AsO3 reduction via the formation of Co-O hybridization bond, leading to a lower energy barrier, promoting the breakage of As-O bonds. Importantly, the first electron transfer is the rate-limiting step of arsenic reduction and is found to be more favorable on Co-SAC both thermodynamically and kinetically. This work not only expands the potential applicaiton of single-atom catalysts in the detection and treatment of As(III), but also provides atomic-level catalytic insights into HMIs sensing interfaces.

16.
Small ; 16(25): e2001035, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32406188

RESUMO

Heavy metal ions (HMIs) are one of the major environmental pollution problems currently faced. To monitor and control HMIs, rapid and reliable detection is required. Electrochemical analysis is one of the promising methods for on-site detection and monitoring due to high sensitivity, short response time, etc. Recently, nanometal oxides with special surface physicochemical properties have been widely used as electrode modifiers to enhance sensitivity and selectivity for HMIs detection. In this work, recent advances in the electrochemical detection of HMIs using nanometal oxides, which are attributed to specific crystal facets and phases, surficial defects and vacancies, and oxidation state cycle, are comprehensively summarized and discussed in aspects of synthesis, characterization, electroanalysis application, and mechanism. Moreover, the challenges and opportunities for the development and application of nanometal oxides with functional surface physicochemical properties in electrochemical determination of HMIs are presented.

17.
Small ; 16(7): e1906830, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31971669

RESUMO

Metal hydroxide nanomaterials are widely applied in the energy and environment fields. The electrochemical performance of such materials is strongly dependent on their crystal phases. However, as there are always multiple factors relating to the phase-dependent electrochemistry, it is still difficult to identify the determining one. The well-defined crystal phases of α- and ß-FeOOH nanorods are characterized through the transmission electron microscopy by a series of rotation toward one rod, where the cross-section shape and the growth direction along the [001] crystalline are first verified for 1D FeOOH nanostructures. The electrosensitivity of the two materials toward Pb(II) is tested, where α-FeOOH performs an outstanding sensitivity whilst it is only modest for ß-FeOOH. Experiments via Fourier transform infrared spectroscopy, X-ray absorption fine structure (XAFS), etc., show that α-FeOOH presents a larger Pb(II) adsorption capacity due to more surficial hydroxyl groups and weaker PbO bond strength. The reaction kinetics are simulated and the adsorption capacity is found to be the determining factor for the distinct Pb(II) sensitivities. Combining experiment with simulation, this work reveals the physical insights of the phase-dependent electrochemistry for FeOOH and provides guidelines for the functional application of metal hydroxide nanomaterials.

18.
Hepatol Res ; 50(12): 1386-1390, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32909341

RESUMO

The severe form of acute exacerbation of hepatitis B during pregnancy is a rare but life-threatening condition for both the mother and the fetus. A 32-year-old pregnant woman at 10 weeks of gestation was diagnosed with acute decompensated liver failure due to acute exacerbation of hepatitis B. The Model for End-stage Liver Disease score was up to 37. The patient was managed carefully with antiviral treatment, fluid resuscitation, correction of coagulopathy, close monitoring of hepatic function, and regular assessment of the fetus. She was transplanted with a deceased liver at 14 weeks and 1 day of gestation. With careful post-transplant care and avoidance of medication with risk of miscarriage and teratogenicity, a healthy baby was delivered at 39 weeks and 1 day of gestation. Herein, we report this critical condition of pregnancy that was complicated with liver failure due to acute exacerbation of hepatitis B, but had favorable outcomes for both the mother and the baby after liver transplantation.

19.
Anal Chem ; 91(15): 9978-9985, 2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31246003

RESUMO

Although it has been recognized that the interference between heavy metal ions (HMIs) becomes a severe problem for the simultaneous electroanalysis of multiple HMIs, the factor leading to the interference is still difficult to identify, due to the limited understanding of the electroanalytic kinetics. In this work, a kinetic model is built for the electroanalysis of HMIs, and the electroanalytic results are simulated for Cd(II), Cu(II), and their mixture as examples for the interference investigation. The mutual interference between Cd and Cu is observed on the glassy carbon electrode. By applying the kinetic model, the replacement of deposited Cd by Cu(II) at the codeposition stage is regarded as the main reason for the interference, and the corresponding suggestion for selecting suitable electrode materials to avoid such interference is also provided.

20.
Small ; 15(35): e1902433, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31304682

RESUMO

The measurement of ultralow concentrations of heavy metal ions (HMIs) in blood is challenging. A new strategy for the determination of mercury ions (Hg2+ ) based on an oriented ZnO nanobelt (ZnO-NB) film solution-gated field-effect transistor (FET) chip is adopted. The FET chips are fabricated with ZnO-NB film channels with different orientations utilizing the Langmuir-Blodgett (L-B) assembly technique. The combined simulation and I-V behavior results show that the nanodevice with ZnO-NBs parallel to the channel has exceptional performance. The sensing capability of the oriented ZnO-NB film FET chips corresponds to an ultralow minimum detectable level (MDL) of 100 × 10-12 m in deionized water due to the change in the electrical double layer (EDL) arising from the synergism of the field-induced effect and the specific binding of Hg2+ to the thiol groups (-SH) on the film surface. Moreover, the prepared FET chips present excellent selectivity toward Hg2+ , excellent repeatability, and a rapid response time (less than 1 s) for various Hg2+ concentrations. The sensing performance corresponds to a low MDL of 10 × 10-9 m in real samples of a drop of blood.


Assuntos
Dispositivos Lab-On-A-Chip , Mercúrio/sangue , Nanoestruturas , Óxido de Zinco/química , Humanos , Limite de Detecção
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