53 research outputs found
MicroNIR/chemometrics assessement of occupational exposure to hydroxyurea
Portable Near Infrared spectroscopy (NIRs) coupled to chemometrics was investigated for the first time as a novel entirely on-site approach for occupational exposure monitoring in pharmaceutical field. Due to a significant increase in the number of patients receiving chemotherapy, the development of reliable, fast, and on-site analytical methods to assess the occupational exposure of workers in the manufacture of pharmaceutical products, has become more and more required. In this work, a fast, accurate, and sensitive detection of hydroxyurea, a cytotoxic antineoplastic agent commonly used in chemotherapy, was developed. Occupational exposure to antineoplastic agents was evaluated by collecting hydroxyurea on a membrane filter during routine drug manufacturing process. Spectra were acquired in the NIR region in reflectance mode by the means of a miniaturized NIR spectrometer coupled with chemometrics. This MicroNIR instrument is a very ultra-compact portable device with a particular geometry and optical resolution designed in such a manner that the reduction in size does not compromise the performances of the spectrometer. The developed method could detect up to 50 ng of hydroxyurea directly measured on the sampling filter membrane, irrespective of complexity and variability of the matrix; thus extending the applicability of miniaturized NIR instruments in pharmaceutical and biomedical analysis
Sol–gel synthesis and thermal behavior of bioactive ferrous citrate–silica hybrid materials
Imbalance of the iron level in the body causes several diseases. In particular, the low level of iron, during pregnancy, is
responsible for the iron deficiency anemia, and even of neurodegenerative diseases. Although the treatment of iron
deficiency anemia with oral iron supplements has been known, this problem still afflicts many people. The aim of this work
was the development of a system able to release ferrous ions in a controlled manner. Controlled drug release for medical
applications, indeed, appears to be a very interesting alternative to a systemic therapy because it is assurance of treatment
continuity and drug stability and optimizes drug absorption. For this purpose, ferrous citrate (Fe(II)C) was synthesized by a
redox reaction between iron powder and citric acid. Fourier transform infrared spectroscopy (FTIR), 1,10-phenanthroline
and sodium thiocyanate colorimetric assays confirmed that only Fe(II)C was obtained by redox reaction. Afterward,
obtained Fe(II)C was embedded within a SiO2 matrix in different mass percentage, by means of a sol–gel route. FTIR
spectroscopy and simultaneous thermogravimetry/first-order derivative of thermogravimetry were used to confirm the
Fe(II)C presence in the silica matrix and to investigate the thermal behavior of the sol–gel materials, respectively. The
bioactivity test carried out by soaking the synthesized drug delivery systems in a simulated body fluid showed that the
biological properties of the silica matrix are not modified by the presence of Fe(II)C
Portable NIR spectroscopy: the route to green analytical chemistry
There is a growing interest for cost-effective and nondestructive analytical techniques in both research and application fields. The growing approach by near-infrared spectroscopy (NIRs) pushes to develop handheld devices devoted to be easily applied for in situ determinations. Consequently, portable NIR spectrometers actually result definitively recognized as powerful instruments, able to perform nondestructive, online, or in situ analyses, and useful tools characterized by increasingly smaller size, lower cost, higher robustness, easy-to-use by operator, portable and with ergonomic profile. Chemometrics play a fundamental role to obtain useful and meaningful results from NIR spectra. In this review, portable NIRs applications, published in the period 2019–2022, have been selected to indicate starting references. These publications have been chosen among the many examples of the most recent applications to demonstrate the potential of this analytical approach which, not having the need for extraction processes or any other pre-treatment of the sample under examination, can be considered the “true green analytical chemistry” which allows the analysis where the sample to be characterized is located. In the case of industrial processes or plant or animal samples, it is even possible to follow the variation or evolution of fundamental parameters over time. Publications of specific applications in this field continuously appear in the literature, often in unfamiliar journal or in dedicated special issues. This review aims to give starting references, sometimes not easy to be found
Monitoring of cannabinoids in hemp flours by MicroNIR/Chemometrics
Cannabinoids in hemp plant are strictly located in the inflorescence, in particular in top side of the plant while a lower amount may be found in the leaves. As a consequence, the lower amount of cannabinoids which can be recovered in the hemp flours is obtained from seeds, thus from contamination during harvesting procedures. To this aim, a screening test for the real time detection of cannabinoids in hemp flour was developed by a miniaturized analytical platform based on the MicroNIR spectrometer. Chemometrics was used to develop models of prediction to identify the cannabinoids and simultaneously to quantify the residual amounts in order to accomplish specific regulatory legislation according to the country. In particular, Partial Least Square-Discriminant Analysis (PLS-DA) and Partial Least Square regression (PLSr) were applied and results demonstrated that MicroNIR/Chemometric platform permit to differentiate hemp flours according to the presence of CBD, THC and CBG. In addition, for each cannabinoid, a quantification method was developed in the range 0.001–0.1 %ww, and their performances were evaluated by comparing results to those obtained by the reference procedures. Processing of the real samples provided a suitable correlation and confirmed the capabilities of this innovative platform to be used for the monitoring of the residual content of cannabinoids in hemp flours
Real time detection of amphetamine in oral fluids by MicroNIR/Chemometrics
In this work, a novel coupled approach MicroNIR/Chemometrics based on a miniaturized and portable spectrometer is proposed for the on site detection of amphetamines (AMP) in non pretreated oral fluids. In particular, the coupling of MicroNIR with chemometrics was investigated with the aim of developing a fast and accurate approach able to perform the on-site prediction of AMP abuse. A predictive model to be used in real cases was developed by collecting specimens from volunteers and spiked samples with increasing amounts of AMP were prepared to optimize calibration. Partial Least Square-Discriminant Analysis (PLS-DA) and Partial Least Square regression (PLS) were involved to detect and quantify AMP. Results demonstrated that MicroNIR/Chemometric platform is statistically able to identify AMP abuse in simulated oral fluid samples containing, with the accuracy and sensitivity of the actual proposed official reference methods. The method was checked against false positive and true positive response and results proved to be those required for confirmatory analyses. This method would permit to simplify AMP abuse monitoring for roadside drug testing or workplace surveillance and may be of help at first aid points
Study of [2-(2\u2019-pyridyl)imidazole] complexes to confirm two main characteristic thermoanalytical behaviors of transition metal complexes based on imidazole derivatives
Imidazole derivative ligands are recognized as useful models for biomimetic complexes. Among
the inorganic\u2013organic hybrid complexes, those with derivatives of imidazole heterocyclic N-donor
ligands are interesting for their framework. In previous studies of complexes with imidazole
derivative ligands, our group reported two main thermally induced decomposition behaviors
supporting two different systematic decomposition trends. In this work, one of these characteristic
decomposition mechanisms was again found. The final goal of these serial studies is the possibility
to provide, by the experimental evidences, a prediction model of thermal stability and
decomposition typical behavior by comparing the structural characteristics of a precipitated
complex.
2-(2\u2019-pyridyl)imidazole complexes with transition metal ions of general formula M(PyrIm)2(H2O)2
(where M = Cu, Zn, Cd, Mn or Co) were synthesized, characterized and studied by thermoanalytical
techniques coupled to mass spectrometry, to suggest their decomposition mechanism by evolved
gas analysis (EGA-MS).
Complexes also showed the interesting possibility to be precipitated with two methanol molecules
in the structure and to replace methanol molecules with water molecules under controlled
conditions
The detection of cannabinoids in veterinary feeds by microNIR/chemometrics: A new analytical platform
In this work, the capabilities of a novel miniaturized and portable microNIR spectrometer were investigated in order to propose a practical and intelligible test allowing the rapid and easy screening of cannabinoids in veterinary feeds. In order to develop a predictive model that could identify and simultaneously quantify the residual amounts of cannabinoids, specimens from popular veterinary feeds were considered and spiked with increasing amounts of cannabidiol (CBD), Δ9-tetrahydrocannabinol (THC), and cannabigerol (CBG). Partial least squares discriminant analysis (PLS-DA) and partial least squares regression (PLSr) were applied for the simultaneous detection and quantification of cannabinoids. The results demonstrated that the microNIR/chemometric platform could statistically identify the presence of CBD, THC and CBG in the simulated samples containing cannabinoids from 0.001 to 0.01%w/w, with the accuracy and sensitivity of the official reference methods actually proposed. The method was checked against false positive and true positive responses, and the results proved to be those required for confirmatory analyses, permitting to provide a fast and accurate method for monitoring cannabinoids in veterinary feeds
MicroNIR/Chemometrics: a new analytical platform for fast and accurate detection of Δ9-Tetrahydrocannabinol (THC) in oral fluids
Background: Δ9-Tetrahydrocannabinol (THC) is already considered one of the most addictive substances since an increasing number of consumers/abusers of THC and THC based products are observed worldwide. In this work, the capabilities of a novel miniaturized and portable MicroNIR spectrometer were investigated in order to propose a practical and intelligible test allowing the rapid and easy screening of Δ9-Tetrahydrocannabinol (THC) oral fluids without any pretreatment. Methods: Specimens from volunteers were collected in order to consider any sources of variability in the spectral response and spiked with increasing amount of THC in order to realize predictive models to be used in real cases. Partial Least Square-Discriminant Analysis (PLS-DA) and Partial Least Square regression (PLSr) for the simultaneously detection and quantification of THC, were applied to baseline corrected spectra pre-treated by first derivative transform. Results: Results demonstrated that MicroNIR/Chemometric platform is statistically able to identify THC abuse in simulated oral fluid samples containing THC from 10 to 100 ng/ml, with a precision and a sensitivity of about 1.51% and 0.1% respectively. Conclusions: The coupling MicroNIR/Chemometrics permits to simplify THC abuse monitoring for roadside drug testing or workplace surveillance and provides the rapid interpretation of results, as once the model is assessed, it can be used to process real samples in a “click-on” device
Development of a "single-click" analytical platform for the detection of cannabinoids in hemp seed oil
In this work, an innovative screening platform is developed and validated for the on site detection of cannabinoids in hemp seed oil, for food safety control of commercial products. The novelty of this completely automated tool consists of a miniaturized NIR spectrometer operating in a wireless mode that permits processing samples in a rapid and accurate way and to obtain in a single click the early detection of a residual amount of cannabinoids in oil, including cannabidiol (CBD), the psychoactive Δ9-tetrahydrocannabinol (THC) and the Δ9-tetrahydrocannabinolic acid (THCA). Simulated samples were realized to instruct the platform and prediction models were developed by chemometric analysis of the NIR spectra using partial least square regression algorithms. Once calibrated, the platform was used to predict samples acquired in the market and on websites. Validation of the system was achieved by comparing results with those obtained from GC-MS analyses and a good correlation was observed
Thermal, chemical and antimicrobial characterization of bioactive titania synthesized by sol–gel method
Chemical stability, anticorrosive properties and photocatalytic activity of titanium dioxide (TiO2) are among the most important characteristics for industrial and environmental applications. It is well known that titanium biomaterials’ properties and response depend significantly on the synthesis method. This work reports the sol–gel synthesis of TiO2 particles, followed by the studies of their structure, thermal analysis and antimicrobial properties. The main issues were to evaluate the chemical structure of the particles by Fourier transform infrared spectroscopy, the thermal behavior by thermogravimetric analysis and the particle size of the TiO2 by SEM and BET experiments. In particular, this characterization aims at verifying the possibility to use these materials to prevent infections after implantation. The antibacterial activity of TiO2 particles was assessed using Escherichia coli and Enterococcus faecalis. Finally, the bioactivity of TiO2 particles were estimated by soaking them for 21 days in simulated body fluid with the view to evaluate their biological properties
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