chemometrics

Application of Innovative TGA/Chemometric Approach for Forensic Purposes: The Estimation of the Time since Death in Contaminated Specimens

Chronothanatology has always been a challenge in forensic sciences. Therefore, the importance of a multidisciplinary approach for the characterization of matrices (organs, tissues, or fluids) that respond linearly to the postmortem interval (PMI) is emerging increasingly. The vitreous humor is particularly suitable for studies aimed at assessing time-related modifications because it is topographically isolated and well-protected.

Update on thalassemia diagnosis: new insights and methods

A novel approach based on Thermogravimetric analysis followed by Chemometrics (TGA/Chemometrics) is provided for Thalassemia diagnosis and a comprehensive study consisting of the coupled approach TGA/Chemometrics, the Complete Blood Count (CBC) and Red Blood Cell (RBC) indices is developed and results are compared. A number of 128 subjects were involved in this study included 16 thalassemia intermedia transfusion-dependent (TI-TD) patients, 18 thalassemia intermedia non transfusion-dependent (TI-NTD) patients, and 14 thalassemia major β (TM-TD) patients.

Miniaturized analytical platform for cocaine detection in oral fluids by MicroNIR/Chemometrics

In the field of forensic toxicology, the use of non-destructive and easy-to-use analytical techniques deserves remarkable attention, especially in those situations involving public health and security. In addition, the miniaturization
and portability of one-touch devices for the detection of specific threats is required more and more.
In this study, a novel on-site MicroNIR/Chemometric platform was developed to perform a real-time prediction
of cocaine and its metabolites in non pre-treated oral fluid.

Flavour component analysis by HS-SPME/GC–MS and chemometric modeling to characterize Pilsner-style Lager craft beers

An HS-SPME/GC–MS (Head Space-Solid Phase Micro Extraction/Gas Chromatography-Mass Spectrometry) method was developed and applied to 79 beers (craft and industrial products) selected among the most common brands of mass-produced beer to evaluate their flavour profile. 111 volatiles were identified in the samples. PLS-DA (Partial Least Squares-Discriminant Analysis) was used to classify beers according to their different production methods.

Flavour fingerprint for the differentiation of grappa from other Italian distillates by GC-MS and chemometrics

An HS-SPME/GC-MS procedure was optimised in order to characterize the aromatic fingerprint of 82 spirit drinks, belonging to Grappa GI samples and other distillates. “Grappa” is a geographical indication (GI) allowed by EC Regulation No 110/2008 only for Italian-made grape marc spirit. Multivariate chemometric techniques were applied to the collected chromatographic profiles in order to classify the samples on the basis of chemical information provided by their volatile composition data.

New methods for thalassemia screening: TGA/chemometrics test is not influenced by the aging of blood samples

The coupling of Thermogravimetry (TG) in conjuction with chemometrics was investigated for the first time to evaluate the capabilities of this novel test to provide the screening of thalassemia in blood samples stored at 4 °C until 15 days. Healthy donors were considered as reference subjects and a typical thermal behaviour as a function of aging was estimated and compared to thermal behaviour of thalassemia subjects. Diagnosis of thalassemia was made at the Day-Hospital Thalassemia of S.

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.

"2 n analytical platform" to update procedures in thanatochemistry: estimation of post mortem interval in vitreous humor

In this work, a novel multiway approach by spectroscopy and thermogravimetry associated with chemometrics is developed, providing a multiparametric characterization of vitreous humor as a function of the time since death. Estimation of the precise time since death was performed on hospital deaths occurred in casualty, by medico-legal and post mortem examination, with no metabolic disorders. Micro and macro elements in vitreous specimens were determined by ICP-OES and were found to be diagnostic in predicting the post mortem interval (PMI).

Chemometrics applied to plant spectral analysis

In this chapter, a survey of the chemometric (data analytical) methods most used for the characterization of plant varieties and cultivars based on spectroscopic measurements is presented. After an introductory section, illustrating the basics of data representation, the main tools for exploratory (descriptive) data analysis and predictive modeling are discussed. In particular, how to predict quantitative responses by multivariate calibration methods and how to assess qualitative attributes by means of classification techniques are addressed.

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