Electrochemical platform based on molecularly imprinted polymer with zinc oxide nanoparticles and multiwalled carbon nanotubes modified screen-printed carbon electrode for amaranth determination.

A novel electrochemical platform for amaranth determination has been developed using a rapid, easy, inexpensive, and portable molecularly imprinted polymer technique. The MIP platform was fabricated by electropolymerizing melamine as monomer in the presence of amaranth as template on the surface of ZnO-MWCNT/SPCE. Then, amaranth was completely eluted, leaving imprinted cavities in the polymeric film that could effectively recognize amaranth in solution. The electrochemical platform based on a molecularly imprinted polymelamine was analyzed by scanning electron microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). Under optimum conditions, the developed MIP/ZnO-MWCNT/SPCE platform can be properly used for amaranth determination, with high sensitivity of 96.2 µA µM cm-2, two linear concentration ranges (0.01 to 1 µM and 1 to 1000 µM) and a low limit of detection of 0.003 µM. The anodic peak potential of amaranth was found to be 0.73 V. Additionally, the polymelamine MIP films specifically recognize amaranth molecules, making it possible to detect amaranth in a complex solution with high selectivity, excellent repeatability, reproducibility, and stability. The MIP/ZnO-MWCNT modified screen-printed carbon electrode was successfully applied to determine amaranth in pharmaceutical and water samples, with recovery values ranging from 99.7 to 102% and RSD% values less than 3.2%.

N-Methylfulleropyrrolidine-Based Multimode Sensor for Determination of Butoconazole Nitrate.

A multimode sensor (a sensor responding simultaneously to more than one mode, e.g., stochastic mode, amperometric mode, voltammetric mode) based on graphite paste modified with N-methylfulleropyrrolidine was proposed for the determination of butoconazole nitrate in its pharmaceutical formulation. The stochastic mode and square wave voltammetry mode were applied for the determinations. Both the stochastic mode and square wave voltammetry mode were applied for a qualitative and quantitative assay of butoconazole nitrate. The sensor can be used between 1.68 × 10-6 and 1.68 × 104 µmol L-1 when the stochastic mode is used and between 0.168 and 16.80 µmol L-1 when the square wave voltammetry mode is used. The multimode sensor was reliably used for the determination of butoconazole nitrate in its pharmaceutical formulation, Gynofort cream, the recorded recoveries being higher than 99.00%, with RSD (%) values of lower than 2.00%.

In-House Validated Map of Lymph Node Stations in a Prospective Cohort of Colorectal Cancer: A Tool for a Better Preoperative Staging.

Preoperative staging of colorectal cancer (CRC) based on imaging techniques such as computed tomography (CT) or magnetic resonance imaging (MRI) is crucial for identification and then removal of the positive lymph nodes (LNs). The aim of this study was to evaluate the correlation between preoperatively seen morphologic criteria (number, size, shape, structure, borders, or enhancement patterns) and histopathological features of LNs using an in-house validated map of nodal stations. A total of 112 patients with CRC that underwent surgery were preoperatively evaluated by CT scans. The locoregional, intermediate, and central LNs were CT-mapped and then removed during open laparotomy and examined under microscope. The analysis of correlations was interpreted using the suspicious-to-positive ratio (SPR) parameter. The greatest correlation was found in tumors located in the sigmoid colon, descending colon and middle rectum; SPR value was 1.12, 1.18, and 1.26, respectively. SPR proved to be 0.59 for cases of the transverse colon. Regarding the enhancement type, the dotted pattern was mostly correlated with metastatic LNs (OR: 7.84; p < 0.0001), while the homogenous pattern proved a reliable indicator of nonmetastatic LNs (OR: 1.99; p < 0.05). A total of 1809 LNs were harvested, with a median value of 15 ± 1.34 LNs/case. Transdisciplinary approach of CRC focused on pre-, intra-, and postoperatively mapping of LNs might increase the accuracy of detecting metastasized nodes for tumors of the distal colon and middle rectum but not for those of the transverse colon. In addition to morphologic criteria, the enhancement pattern of LNs can be used as a predictor of nodal involvement improving the CT-based preoperative staging.

A Screening Test for Early Diagnosis of Microcellular Bronchopulmonary Cancer-Pilot Study.

INTRODUCTION: According to WHO, in worldwide cancer mortality statistics, the first place is occupied by bronchopulmonary cancer. This reason has led us to carry out the present pilot study, was with the participation of the Clinics of Carol Davila University of Medicine and Pharmacy Bucharest in order to apply a technique developed earlier by Stefan-van Staden, for early detection of this type of cancer, initiate a personalized diagnosis, and implicitly apply a personalized treatment in order to increase the life expectancy among these patients. In recent years, there has been a tendency to find fast non-invasive screening methods for the early diagnosis of cancer. Therefore, the present pilot study proposed simultaneous detection of tumor markers (NSE and CEA) by different methods: (1) ELISA kits, (2) the method developed earlier by Stefan-van Staden-which used stochastic sensors, and (3) IHC. All selected patients selected by Dr Claudiu-Eduard Nistor, were suspected of microcellular bronchopulmonary cancer. Tumor tissue samples were collected by conventional and minimally invasive surgical techniques. The results obtained for the detection of markers in blood using ELISA, and stochastic methods (based on stochastic sensors) were correlated with the results obtained using anatomopathological and immunohistochemical analysis of the tumor tissues. EXPERIMENTAL: Stochastic sensors have been used to analyze NSE in blood samples and whole tissues. The IHC was performed for analyzing tumor tissue using standard procedures. ELISA has been used as a standard method to determine specific biomarkers in whole blood samples. RESULTS AND DISCUSSION: A good correlation was found for results obtained using stochastic and ELISA methods, and IHC for blood and tissue analysis. Statistical evaluation of the data showed that the results of whole blood analysis are correlating very good with the analysis of pulmonary tumor tissue. Therefore, the stochastic method can be used for the detection and for the pursuit of therapeutic efficiency. CONCLUSIONS: The data obtained, as well as the statistics, showed that the proposed method can be used as a screening method for fast and early detection of microcellular bronchopulmonary, being minim invasive. It can also be used for monitoring the therapeutic efficiency of the prescribed medication.

Advanced Methods for the Analysis of Testosterone.

Testosterone is the principal endogenous androgenic-anabolic steroid in humans. The levels of testosterone in the human body are correlated with many hormonal disorders (hypogonadism, impotence, etc) mostly in men, and with many types of diseases such as: prostate cancer, metabolic syndrome, obesity, cardiovascular diseases and so on. Testosterone is extensively used among sportsmen willing to increase strength, aggressiveness, and recovery; making it the most commonly reported substance in steroid abuse. Fast, easy and cheap methods for the evaluation of testosterone are extremely needed in clinics and hospitals. This review is dedicated to surveying recent determination methods of testosterone from different biological samples such as: serum, saliva, plasma, urine or fingernail samples. After a brief description of the role of this steroid hormone in the biomedical field, various types of determination methods are described. The most important methods are immunoassays, liquid chromatography tandem massspectrometry and electrochemical methods. Different types of sensors were designed for the rapid assessment of testosterone: immunosensors, biosensors, stochastic or multimode sensors. One can conclude that to date, the available methods of analysis can cover a wide concentration range, able to detect testosterone from children`s saliva, where the levels are the lowest (using stochastic sensors), to whole blood, where electrochemical, immunological and chromatographic methods can be used.