Oxygen Vacancy-Enriched CoFe2O4 for Electrochemically Sensitive Detection of the Breast Cancer CD44 Biomarker.

Enhancing the selectivity of detection methods is essential to distinguish breast cancer biomarker cluster of differentiation 44 (CD44) from other species and reduce false-positive or false-negative results. Here, oxygen vacancy-enriched CoFe2O4 (CoFe2O4-x) was crafted, and its implementation as an electrochemical electrode for the detection of CD44 biomarkers has been scrutinized. This unique electrode material offers significant benefits and novel features that enhance the sensitivity and selectivity of the detection process. The oxygen vacancy density of CoFe2O4-x was tuned by adjusting the mass ratios of iron to cobalt precursors (iron-cobalt ratio) and changing annealing atmospheres. Electrochemical characterization reveals that, when the iron-cobalt ratio is 1:0.54 and the annealing atmosphere is nitrogen, the as-synthesized CoFe2O4-x electrode manifests the best electrochemical activity. The CoFe2O4-x electrode demonstrates high sensitivity (28.22 µA (ng mL)-1 cm-2), low detection limit (0.033 pg mL-1), and robust stability (for 11 days). Oxygen vacancies can not only enhance the conductivities of CoFe2O4 but also provide better adsorption of -NH2, which is beneficial for stability and electrochemical detection performance. The electrochemical detection signal can be amplified using CoFe2O4-x as a signal probe. Additionally, it is promising to know that the CoFe2O4-x electrode has shown good accuracy in real biological samples, including melanoma cell dilutions and breast cancer patient sera. The electrochemical detection results are comparable to ELISA results, which indicates that the CoFe2O4-x electrode can detect CD44 in complex biological samples. The utilization of CoFe2O4-x as the signal probe may expand the application of CoFe2O4-x in biosensing fields.

Coronavirus disease 2019 (COVID-19) associated coagulopathy and its impact on outcomes in Shenzhen, China: A retrospective cohort study.

BACKGROUND: Early detection of suspected critical patients infected with coronavirus disease 2019 (COVID-19) is very important for the treatment of patients. This study aimed to investigate the role of COVID-19 associated coagulopathy (CAC) to preview and triage. METHODS AND RESULTS: A cohort study was designed from government designated COVID-19 treatment center. CAC was defined as International Society on Thrombosis and Haemostasis (ISTH) score ≥2. Data from 117 patients COVID-19 were reviewed on admission. The primary and secondary outcomes were admission to Intensive Care Unit (ICU), the use of mechanical ventilation, vital organ dysfunction, discharges of days 14, 21 and 28 from admission and hospital mortality. Among them, admission to ICU was increased progressively from 16.1% in patients with non-CAC to 42.6% in patients with CAC (P < 0.01). Likely, invasive ventilation and noninvasive ventilation were increased from 1.8%, 21.4% in patients with non-CAC to 21.3%, 52.5% in patients with CAC, respectively (P < 0.01). The incidences of acute hepatic injury and acute respiratory distress syndrome in non-CAC and CAC were 28.6% vs. 62.3%, 8.9% vs. 27.9%, respectively (P < 0.01). The discharges of days 14, 21 and 28 from admission were more in non-CAC than those of CAC (P < 0.05). Multiple logistic regression results showed that ISTH score ≥2 was obviously associated with the admission to ICU (OR 4.07, 95% CI 1.47-11.25 P = 0.007) and the use of mechanical ventilation (OR 5.54, 95% CI 2.01-15.28 P = 0.001) in patients with COVID-19. CONCLUSION: All results show ISTH score ≥2 is an important indicator to preview and triage for COVID-19 patients.

Hydrophobic networked PbO2 electrode for electrochemical oxidation of paracetamol drug and degradation mechanism kinetics.

A hydrophobic networked PbO2 electrode was deposited on mesh titanium substrate and utilized for the electrochemical elimination towards paracetamol drug. Three dimensional growth mechanism of PbO2 layer provided more loading capacity of active materials and network structure greatly reduced the mass transfer for the electrochemical degradation. The active electrochemical surface area based on voltammetric charge quantity of networked PbO2 electrode is about 2.1 times for traditional PbO2 electrode while lower charge transfer resistance (6.78 Ω cm2) could be achieved on networked PbO2 electrode. The electrochemical incineration kinetics of paracetamol drug followed a pseudo first-order behavior and the corresponding rate constant were 0.354, 0.658 and 0.880 h-1 for traditional, networked PbO2 and boron doped diamond electrode. Higher electrochemical elimination kinetics could be achieved on networked PbO2 electrode and the performance can be equal to boron doped diamond electrode in result. Based on the quantification of reactive oxidants (hydroxyl radicals), the utilization rate of hydroxyl radicals could reach as high as 90% on networked PbO2 electrode. The enhancement of excellent electrochemical oxidation capacity towards paracetamol drug was related to the properties of higher loading capacity, enhanced mass transfer and hydrophobic surface. The possible degradation mechanism and pathway of paracetamol on networked PbO2 electrode were proposed in details accordingly based on the intermediate products.

A hydrophobic three-dimensionally networked boron-doped diamond electrode towards electrochemical oxidation.

A boron-doped diamond electrode with a three-dimensional network was fabricated on a mesh titanium substrate. Properties such as higher surface area, enhanced mass transfer and a hydrophobic surface endowed the prepared electrode with excellent electrochemical oxidation ability towards contaminants.