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Applied Spectroscopy Jan 2022There is considerable confusion when naming vibrations in infrared and Raman spectra. One of the most common errors is the identification of some stretching and bending...
There is considerable confusion when naming vibrations in infrared and Raman spectra. One of the most common errors is the identification of some stretching and bending vibrations as "asymmetric". There are no asymmetric vibrations as such vibrations incur rotations and translations. The correct term is antisymmetric and it is demonstrated, through molecular symmetry operations, why this is the correct term.
Topics: Minerals; Spectrophotometry, Infrared; Spectrum Analysis, Raman; Vibration
PubMed: 34355579
DOI: 10.1177/00037028211036509 -
Biosensors Nov 2020Plant stresses have been monitored using the imaging or spectrometry of plant leaves in the visible (red-green-blue or RGB), near-infrared (NIR), infrared (IR), and... (Review)
Review
Plant stresses have been monitored using the imaging or spectrometry of plant leaves in the visible (red-green-blue or RGB), near-infrared (NIR), infrared (IR), and ultraviolet (UV) wavebands, often augmented by fluorescence imaging or fluorescence spectrometry. Imaging at multiple specific wavelengths (multi-spectral imaging) or across a wide range of wavelengths (hyperspectral imaging) can provide exceptional information on plant stress and subsequent diseases. Digital cameras, thermal cameras, and optical filters have become available at a low cost in recent years, while hyperspectral cameras have become increasingly more compact and portable. Furthermore, smartphone cameras have dramatically improved in quality, making them a viable option for rapid, on-site stress detection. Due to these developments in imaging technology, plant stresses can be monitored more easily using handheld and field-deployable methods. Recent advances in machine learning algorithms have allowed for images and spectra to be analyzed and classified in a fully automated and reproducible manner, without the need for complicated image or spectrum analysis methods. This review will highlight recent advances in portable (including smartphone-based) detection methods for biotic and abiotic stresses, discuss data processing and machine learning techniques that can produce results for stress identification and classification, and suggest future directions towards the successful translation of these methods into practical use.
Topics: Algorithms; Biosensing Techniques; Hyperspectral Imaging; Machine Learning; Plant Physiological Phenomena; Spectroscopy, Near-Infrared; Stress, Physiological; Support Vector Machine
PubMed: 33260412
DOI: 10.3390/bios10120193 -
Food Chemistry Aug 2019Chemical compositions of mushrooms are greatly dependent on the geographical region, and also the different parts of the same mushroom have different chemical... (Review)
Review
Chemical compositions of mushrooms are greatly dependent on the geographical region, and also the different parts of the same mushroom have different chemical constitutions. Several chemical methods are employed for quality control of mushrooms. However, these methods are destructive, require skilled personnel and are time consuming. To overcome these limitations researchers are aiming for vibrational spectroscopic techniques. This review is focused on various studies related to the application of vibrational spectroscopy for classification, authentication and quality analysis of mushrooms. It was concluded that vibrational spectroscopy could be efficiently employed for assessing the quality, authenticity and geographical origin of the mushrooms. Fourier-transform infrared (FTIR) and near infrared (NIR) spectroscopy were the most explored, whereas, Raman spectroscopy is the least explored technique in this field. Compact and cost-effective spectrometers based on the selective wavelengths have to be designed and installed at commercial and industrial level for rapid quality control of mushrooms.
Topics: Agaricales; Food Analysis; Geography; Quality Control; Spectroscopy, Fourier Transform Infrared; Spectroscopy, Near-Infrared; Spectrum Analysis; Spectrum Analysis, Raman; Vibration
PubMed: 30955647
DOI: 10.1016/j.foodchem.2019.03.091 -
Critical Reviews in Analytical Chemistry 2021In every developed and developing country, the major facing problem is heavy metals toxicity. Due to there is an increase in the heavy metals anthropogenic in day to day... (Review)
Review
In every developed and developing country, the major facing problem is heavy metals toxicity. Due to there is an increase in the heavy metals anthropogenic in day to day life by various factors, which are causing serious issues or harmful health hazardous for all types of living organisms. Moreover, they are present everywhere in the universe it causes the contamination of the food, dietary, and processed materials. Accordingly, the present review article further summarizes the studies related to the determination of lead as a toxic impurity with a total of 134 references in the period 2000 to 2018. In this write-up, emphasize the one of the highly toxic heavy metal element Lead (Pb) and it's toxicity in the animals, humans, plants, and aquatic systems. In addition, the purpose of this article is to evaluate the effectiveness of established analytical techniques and trends in analytical methods like AAS; ICP-OES; ICP-MS; ASV; X-ray fluorescence spectrometry, these techniques significantly applicable for the quantitative analysis of Pb in various sources. The various regulatory authorities for Pb throughout the globe like IOSH, EPA, EMA, and CDCSO. This reveals the need and scope of further research in the field of heavy metal toxicity and development of new analytical techniques in meeting the needs of the life scientists. The present comprehensive review is an attempt to transform the state of knowledge into the findings that may act as a guideline for all the interested groups at different levels.
Topics: Animals; Humans; Lead; Pharmaceutical Preparations; Spectrum Analysis
PubMed: 31650860
DOI: 10.1080/10408347.2019.1678381 -
Journal of Food and Drug Analysis Jun 2023Combination of piperaquine (PQ) (320mg) and dihydroartemisinin (DHA) (40 mg) is an anti-malarial formulation, which is recommended by World Health Organization (WHO)....
Combination of piperaquine (PQ) (320mg) and dihydroartemisinin (DHA) (40 mg) is an anti-malarial formulation, which is recommended by World Health Organization (WHO). Simultaneous analysis of PQ and DHA can be problematic due to the lack of chromophores or fluorophores in DHA molecule. Whereas PQ possesses strong UV absorption and it presents in 8 times of DHA contents in the formulation. In this study, two spectroscopic methods, Fourier transform infrared (FTIR) and Raman spectroscopy, were developed for the determination of both drugs in combined tablets. The FTIR and Raman spectra were recorded in the attenuate total reflectance (ATR) and scattering modes, respectively. The original and pretreated spectra from FTIR and handheld-Raman were subjected to Unscrambler® program to construct partial least squares regression (PLSR) model comparing with references values obtained from high performance liquid chromatography (HPLC)-UV method. The optimal PLSR models of PQ and DHA from FTIR spectroscopy were obtained from orthogonal signal correction (OSC) pretreatment at the wavenumbers 400-1,800 cm and 1,400-4,000 cm, respectively. For Raman spectroscopy of PQ and DHA, the optimal PLSR models were obtained from standard normal variate (SNV) pretreatment at the wavenumbers 1,200-2,300 cm and OSC pretreatment at the wavenumber 400-2,300 cm, respectively. Determination of PQ and DHA in tablets from the optimum model was compared with HPLC-UV method. Results were not significantly different at 95% confidence limit (p-value >0.05). The chemometrics-assisted spectroscopic methods were fast (1-3 min), economical and less labor intensive. Moreover, the handheld Raman spectrometer is portable and can be utilized for onsite analysis to facilitate the detection of counterfeit or substandard drugs at ports of entry.
Topics: Antimalarials; Chemometrics; Spectroscopy, Fourier Transform Infrared; Spectrum Analysis, Raman; Tablets
PubMed: 37335160
DOI: 10.38212/2224-6614.3449 -
Spectrochimica Acta. Part A, Molecular... Aug 2019Cancer is the second-leading cause of death worldwide. It affects an unfathomable number of people, with almost 16 million Americans currently living with it. While many... (Review)
Review
Cancer is the second-leading cause of death worldwide. It affects an unfathomable number of people, with almost 16 million Americans currently living with it. While many cancers can be detected, current diagnostic efforts exhibit definite room for improvement. It is imperative that a person be diagnosed with cancer as early on in its progression as possible. An earlier diagnosis allows for the best treatment and intervention options available to be presented. Unfortunately, existing methods for diagnosing cancer can be expensive, invasive, inconclusive or inaccurate, and are not always made during initial stages of the disease. As such, there is a crucial unmet need to develop a singular universal method that is reliable, cost-effective, and non-invasive and can diagnose all forms of cancer early-on. Raman spectroscopy in combination with advanced statistical analysis is offered here as a potential solution for this need. This review covers recently published research in which Raman spectroscopy was used for the purpose of diagnosing cancer. The benefits and the risks of the methodology are presented; however, there is overwhelming evidence that suggests Raman spectroscopy is highly suitable for becoming the first universal method to be used for diagnosing cancer.
Topics: Animals; Early Detection of Cancer; Equipment Design; Humans; Models, Statistical; Neoplasms; Spectrum Analysis, Raman
PubMed: 31075613
DOI: 10.1016/j.saa.2019.04.067 -
Critical Reviews in Food Science and... 2023As one of the main functional substances, carbohydrates account for a large proportion of the human diet. Conventional analysis and detection methods of dietary... (Review)
Review
As one of the main functional substances, carbohydrates account for a large proportion of the human diet. Conventional analysis and detection methods of dietary carbohydrates and related products are destructive, time-consuming, and labor-intensive. In order to improve the efficiency of measurement and ensure food nutrition and consumer health, rapid and nondestructive quality evaluation techniques are needed. In recent years, terahertz (THz) spectroscopy, as a novel detection technology with dual characteristics of microwave and infrared, has shown great potential in dietary carbohydrate analysis. The current review aims to provide an up-to-date overview of research advances in using the THz spectroscopy technique in analysis and detection applications related to dietary carbohydrates. In the review, the principles of the THz spectroscopy technique are introduced. Advances in THz spectroscopy for quantitative and qualitative analysis and detection in dietary carbohydrate-related research studies from 2013 to 2022 are discussed, which include analysis of carbohydrate concentrations in liquid and powdery foods, detection of foreign body and chemical residues in carbohydrate food products, authentication of natural carbohydrate produce, monitoring of the fermentation process in carbohydrate food production and examination of crystallinity in carbohydrate polymers. In addition, applications in dietary carbohydrate-related detection research using other spectroscopic techniques are also briefed for comparison, and future development trends of THz spectroscopy in this field are finally highlighted.
Topics: Humans; Terahertz Spectroscopy; Dietary Carbohydrates; Spectrum Analysis
PubMed: 36647744
DOI: 10.1080/10408398.2023.2165032 -
Analytical Chemistry Jan 2021
Review
Topics: Animals; Humans; Lipids; Mass Spectrometry; Multimodal Imaging; Peptides; Pharmaceutical Preparations; Polysaccharides; Proteins; Spectroscopy, Fourier Transform Infrared; Spectrum Analysis, Raman
PubMed: 33253546
DOI: 10.1021/acs.analchem.0c04595 -
The British Journal of Dermatology Sep 2022
Topics: Humans; Mass Spectrometry; Skin; Spectrum Analysis, Raman
PubMed: 34811723
DOI: 10.1111/bjd.20902 -
Natural Product Reports Dec 2020Covering: 2015 to up to 2019 This review presents the recent progress towards elucidating the structures of chiral natural products and applications using vibrational... (Review)
Review
Covering: 2015 to up to 2019 This review presents the recent progress towards elucidating the structures of chiral natural products and applications using vibrational optical activity (VOA) spectroscopy. Vibrational circular dichroism (VCD) and vibrational Raman optical activity (VROA) are two separate branches of VOA spectroscopy, providing independent and complementary structural information. While determining the absolute configuration (AC) of a given natural product is the primary goal, the determination or assessment of major conformations associated with each diastereomer is also a significant part of this enquiry. The latest developments in experimental and computational aspects of VOA spectroscopies and their applications for inferring the AC and predominant conformations of natural products are summarized. The prospects and limitations in the application of VOA spectroscopy to new natural products are summarized.
Topics: Biological Products; Molecular Structure; Spectrum Analysis; Vibration
PubMed: 32608433
DOI: 10.1039/d0np00025f