RESUMO
With the continuous development in nanoscience and nanotechnology, analytical techniques like surface-enhanced Raman spectroscopy (SERS) render structural and chemical information of a variety of analyte molecules in ultra-low concentration. Although this technique is making significant progress in various fields, the reproducibility of SERS measurements and sensitivity towards small molecules are still daunting challenges. In this regard, microfluidic surface-enhanced Raman spectroscopy (MF-SERS) is well on its way to join the toolbox of analytical chemists. This review article explains how MF-SERS is becoming a powerful tool in analytical chemistry. We critically present the developments in SERS substrates for microfluidic devices and how these substrates in microfluidic channels can improve the SERS sensitivity, reproducibility, and detection limit. We then introduce the building materials for microfluidic platforms and their types such as droplet, centrifugal, and digital microfluidics. Finally, we enumerate some challenges and future directions in microfluidic SERS. Overall, this article showcases the potential and versatility of microfluidic SERS in overcoming the inherent issues in the SERS technique and also discusses the advantage of adding SERS to the arsenal of microfluidics.
Assuntos
Microfluídica , Análise Espectral Raman , Nanotecnologia , Reprodutibilidade dos Testes , Análise Espectral Raman/métodosRESUMO
Differences in epaAC© in heart failure patients with or without readmission: A retrospective case-control study Abstract. Background: Heart failure is one of the most frequent reasons for hospitalization in elderly people. In heart failure, approximately 22.8 % of hospitalised patients are rehospitalised within 30 days. The nursing assessment tool epaAC could provide information on risk factors for readmission. Aim: The aim of this study was to identify possible group differences in the items and scores of the epaAC discharge assessment with regard to the endpoint of unplanned readmissions within 30 days after discharge from index-hospitalisation. Methods: Using a retrospective case-control design, differences in the epaAC variables were investigated by descriptive and comparative statistics. Chi-square test, Wilcoxon test and t-test were performed with two-sided alpha level α < 0.05. Alpha error accumulation was accounted for by Benjamini & Hochberg correction. Results: No significant group differences were found in all items and scores of the discharge epaAC. There is only weak evidence that the presence of acute respiratory impairment at time of discharge is higher in the patient with rehospitalisation than in those without rehospitalisation. Conclusions: The items and scores of the nursing assessment instrument epaAC did not significantly differ between patients with or without 30-days readmission. Further exploration to assess the epaAC's potential to predict rehospitalisation in heart failure is needed.
Assuntos
Insuficiência Cardíaca , Readmissão do Paciente , Idoso , Estudos de Casos e Controles , Humanos , Alta do Paciente , Estudos Retrospectivos , Fatores de RiscoRESUMO
An electrochemical approach to enable surface-enhanced Raman spectroscopy (SERS) detection in continuous microflow is presented. This is achieved by the integration of a silver electrode as SERS substrate in a microfluidic chip device. By the application of actuation pulses of about 4 V, otherwise irreversibly adsorbed analytes are stripped off, which enables quasi-real-time SERS detection in a continuous microflow. The approach opens up a way for in situ SERS monitoring of compounds in microflow with high application potential in microseparation techniques like HPLC and lab-on-a-chip devices.
