Electrochemical Fingerprint of Arsenic (III) by Using Hybrid Nanocomposite-Based Platforms

Arsenic, one of the most abundant mineral and also one to the most toxic compounds. Due to its high toxicity sensitive analytical methods are highly important, taking into account that the admitted level is in the range of µg L−1. A novel and easy to use platform for As(III) detection from water samples is proposed, based on gold and platinum bi metallic nanoparticles and a conductive polymer (polyaniline). The electrochemical detection was achieved after optimization of cathodic pre-concentration and stripping parameters by square wave anodic stripping voltammetry at modified screen-printed carbon-based electrochemical cells, proving its applicability for disposable and cost-effective in situ analysis of arsenic

Nano-Biosensing Platforms for Detection of Cow’s Milk Allergens: An Overview

Among prevalent food allergies, cow milk allergy (CMA) is most common and may persist throughout the life. The allergic individuals are exposed to a constant threat due to milk proteins’ presence in uncounted food products like yogurt, cheese, and bakery items. The problem can be more severe due to cross-reactivity of the milk allergens in the food products due to homologous milk proteins of diverse species. This problem can be overcome by proper and reliable food labeling in order to ensure the life quality of allergic persons. Therefore, highly sensitive and accurate analytical techniques should be developed to detect the food allergens. Here, significant research advances in biosensors (specifically immunosensors and aptasensors) are reviewed for detection of the milk allergens. Different allergic proteins of cow milk are described here along with the analytical standard methods for their detection. Additionally, the commercial status of biosensors is also discussed in comparison to conventional techniques like enzyme-linked immunosorbent assay (ELISA). The development of novel biosensing mechanisms/kits for milk allergens detection is imperative from the perspective of enforcement of labeling regulations and directives keeping in view the sensitive individuals

Quantitative Colorimetric Sensing of Carbidopa in Anti-Parkinson Drugs Based on Selective Reaction with Indole-3-Carbaldehyde

The quality of life of patients affected by Parkinson’s disease is improved by medications containing levodopa and carbidopa, restoring the dopamine concentration in the brain. Accordingly, the affordable quality control of such pharmaceuticals is very important. Here is reported the simple and inexpensive colorimetric quantification of carbidopa in anti-Parkinson drugs by the selective condensation reaction between the hydrazine group from carbidopa and the formyl functional group of selected aldehydes in acidified hydroalcoholic solution. An optical assay was developed by using indole-3-carbaldehyde (I3A) giving a yellow aldazine in EtOH:H2O 1:1 (λmax~415 nm) at 70 °C for 4 h, as confirmed by LC-MS analysis. A filter-based plate reader was used for colorimetric data acquisition, providing superior results in terms of analytical performances for I3A, with a sensitivity ~50 L g−1 and LOD ~0.1 mg L−1 in comparison to a previous study based on vanillin, giving, for the same figures of merit values, about 13 L g−1 and 0.2–0.3 mg L−1, respectively. The calibration curves for the standard solution and drugs were almost superimposable, therefore excluding interference from the excipients and additives, with very good reproducibility (avRSD% 2–4%) within the linear dynamic range (10 mg L−1–50 mg L−1)

Sensing of Catecholamine in Human Urine Using a Simple Colorimetric Assay Based on Direct Melanochrome and Indolequinone Formation

We used the first enzyme-free synthesis and stabilization of soluble melanochrome (MC) and 5,6-indolequinone (IQ) derived from levodopa (LD), dopamine (DA), and norepinephrine (NE) oxidation to develop a simple colorimetric assay for catecholamine detection in human urine, also elucidating the time-dependent formation and molecular weight of MC and IQ using UV–Vis spectroscopy and mass spectrometry. The quantitative detection of LD and DA was achieved in human urine using MC as a selective colorimetric reporter to demonstrate the potential assay applicability in a matrix of interest in therapeutic drug monitoring (TDM) and in clinical chemistry. The assay showed a linear dynamic range between 5.0 mg L−1 and 50.0 mg L−1, covering the concentration range of DA and LD found in urine samples from, e.g., Parkinson’s patients undergoing LD-based pharmacological therapy. The data reproducibility in the real matrix was very good within this concentration range (RSDav% 3.7% and 6.1% for DA and LD, respectively), also showing very good analytical performances with the limits of detection of 3.69 ± 0.17 mg L−1 and 2.51 ± 0.08 mg L−1 for DA and LD, respectively, thus paving the way for the effective and non-invasive monitoring of dopamine and levodopa in urine from patients during TDM in Parkinson’s disease

Association between Renal Function at Admission and COVID-19 in-Hospital Mortality in Southern Italy: Findings from the Prospective Multicenter Italian COVOCA Study

Background. Evidence has shown a close association between COVID-19 infection and renal complications in both individuals with previously normal renal function and those with chronic kidney disease (CKD). Methods. The aim of this study is to evaluate the in-hospital mortality of SARS-CoV-2 patients according to their clinical history of CKD or estimated glomerular filtration rate (eGFR). This is a prospective multicenter observational cohort study which involved adult patients (>= 18 years old) who tested positive with SARS-CoV-2 infection and completed their hospitalization in the period between November 2020 and June 2021. Results. 1246 patients were included in the study, with a mean age of 64 years (SD 14.6) and a median duration of hospitalization of 15 days (IQR 9-22 days). Cox's multivariable regression model revealed that mortality risk was strongly associated with the stage of renal impairment and the Kaplan-Meier survival analysis showed a progressive and statistically significant difference (p < 0.0001) in mortality according to the stage of CKD. Conclusion. This study further validates the association between CKD stage at admission and mortality in patients hospitalized for COVID-19. The risk stratification based on eGFR allows clinicians to identify the subjects with the highest risk of intra-hospital mortality despite the duration of hospitalization