Accuracies and detection limits of major, minor, and trace element quantification in rocks by portable laser-induced breakdown spectroscopy

Discrimination of gallbladder stone employing Laser-Induced Breakdown Spectroscopy (LIBS) and Photoacoustic Spectroscopy (PAS).

Edible gelatin has been widely used as a food additive in the food industry, and illegal adulteration with industrial gelatin will cause serious harm to human health. The present work used laser-induced breakdown spectroscopy (LIBS) coupled with the partial least square-support vector machine (PLS-SVM) method for the fast and accurate estimation of edible gelatin adulteration. Gelatin samples with 11 different adulteration ratios were prepared by mixing pure edible gelatin with industrial gelatin, and the LIBS spectra were recorded to analyze their elemental composition differences. The PLS, SVM, and PLS-SVM models were separately built for the prediction of gelatin adulteration ratios, and the hybrid PLS-SVM model yielded a better performance than only the PLS and SVM models. Besides, four different variable selection methods, including competitive adaptive reweighted sampling (CARS), Monte Carlo uninformative variable elimination (MC-UVE), random frog (RF), and principal component analysis (PCA), were adopted to combine with the SVM model for comparative study; the results further demonstrated that the PLS-SVM model was superior to the other SVM models. This study reveals that the hybrid PLS-SVM model, with the advantages of low computational time and high prediction accuracy, can be employed as a preferred method for the accurate estimation of edible gelatin adulteration.

https://www.mdpi.com/1424-8220/19/19/4225/pdf

Edible Gelatin Diagnosis Using Laser-Induced Breakdown Spectroscopy and Partial Least Square Assisted Support Vector Machine.

Diabetes mellitus, known as diabetes, is a challenging issue, and to control diabetes, a large population is lining toward ayurvedic medicine. In the present study, four brands of anti-diabetic ayurvedic medicines, along with a home remedy, are analyzed using the laser-induced breakdown spectroscopic (LIBS) technique. The study is carried out to know the elements responsible for glycemic potential. The laser-induced breakdown (LIB) spectra elucidate the presence of organic and inorganic elements like Al, Ba, C, Ca, Cu, Fe, H, K, Mg, N, Na, O, Si, Sr, Zn, and the molecular band of CN molecule in medicines. LIBS result also reveals Na and K's distinct concentration, which plays a vital role in diabetes management. The presence of the CN band and organic elements indicate the presence of organic molecular compositions in medicines. For confirmation of organic composition in the drugs, Fourier transform infrared spectroscopy (FT-IR) has been performed. Principal component analysis (PCA) on the LIBS data of the medicines has been used for instant discrimination based on their elemental/molecular compositions.

/pdf/evaluation-of-na-and-k-in-anti-diabetic-ayurvedic-medicine-1jtwmnqyhk.pdf

Evaluation of Na and K in anti-diabetic ayurvedic medicine using LIBS

CN diatomic emission for N determination by LIBS

Laser-induced breakdown spectroscopy (LIBS) of pharmaceutical drugs that contain paracetamol was investigated in air and argon atmospheres. The characteristic neutral and ionic spectral lines of various elements and molecular signatures of CN violet and C2 Swan band systems were observed. The relative hardness of all drug samples was measured as well. Principal component analysis, a multivariate method, was applied in the data analysis for demarcation purposes of the drug samples. The CN violet and C2 Swan spectral radiances were investigated for evaluation of a possible correlation of the chemical and molecular structures of the pharmaceuticals. Complementary Raman and Fourier-transform-infrared spectroscopies were used to record the molecular spectra of the drug samples. The application of the above techniques for drug screening are important for the identification and mitigation of drugs that contain additives that may cause adverse side-effects.

https://www.mdpi.com/2218-2004/7/3/71/pdf

Rai

Papers

Atomic and Molecular Laser-Induced Breakdown Spectroscopy of Selected Pharmaceuticals