Variational study of the constituents of cholesterol stones by laser-induced breakdown spectroscopy

Effect of mineral elements on the formation of gallbladder stones using spectroscopic techniques

Long-standing gallbladder stones have been recognized as one of the highest risk factors for gallbladder cancer. However, the growth and progression of gallbladder stones are still not well-known, and their uncovering requires accurate information on the formation/nucleation and complex compositional information of gallstones. Multiple and single gallstones are analyzed using laser-induced breakdown spectroscopy (LIBS), photoacoustic spectroscopy (PAS), and Fourier transform infrared spectroscopy (FTIR). Spectral signatures as well as spatial variation in the spectral intensities of different elements are observed in the LIBS spectra of the gallstones. In the multiple-type gallstones, the concentration of inorganic content increases from core to periphery, whereas a single gallstone shows the opposite trend from the point of nucleation/core. It is suggested that the concentration of inorganic elements (Mg, Ca, K, and Na) plays an important role in the nucleation and growth of gallstones; thus, accordingly, multiple- and single-type gallstones are found in the gallbladder. The presence of different electronic bands of molecules, such as CH, C2, CN, and NH, is confirmed by LIBS and FTIR. PAS has identified molecules, such as cholesterol, calcium carbonate, and calcium phosphate, in different gallstone samples. These results show that PAS combined with LIBS is a promising candidate for the compositional analysis of gallstones. Furthermore, principal component analysis (PCA) is used to discriminate different layers present in the gallstones.

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

Compositional analysis of gallstone samples has been carried out, using Laser-Induced Breakdown Spectroscopy (LIBS) and Photoacoustic Spectroscopy (PAS). Classification of gallstone has been made on the basis of intensities of the inorganic and organic constituents present in the LIBS spectra. A regression plot is drawn between LIBS spectral intensities of organic & inorganic elements and the stoichiometric ratio of Cholesterol, Bilirubin and Calcium Carbonate. Atomic lines of various elements, as well as molecular signatures of CaO Orange band, CN Violet band, and C₂ Swan band, are observed in LIBS spectra. The relative hardness of gallstones is estimated from the intensity ratio of ionic to neutral atomic lines of the species observed in LIBS spectra. PAS is used for detecting molecular constituents in the gallstones. Principal Component Analysis (PCA) is performed for the discrimination of gallstones. It is found that PAS data, in combination with LIBS provide a suitable method for the compositional analysis of gallstones.

Analysis of stones formed in the human gall bladder and kidney using advanced spectroscopic techniques

Stone diseases (gallstones and kidney stones) are extremely painful and often cause death. The prime aim of biomedical research in this area has been determination of factors resulting in stone formation inside the gallbladder and urinary tract. Many theories have been put forward to explain the mechanism of stone formation and their growth; however, their complete cycle of pathogenesis is still under debate. Several factors are responsible for stone formation; however, much emphasis is placed on the determination of elemental and molecular composition of the stones. In the present review article, we describe different kinds of spectroscopic techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray fluorescence (XRF) spectroscopy, time-of-flight secondary ion mass spectrometry (TOF-SIMS), and laser-induced breakdown spectroscopy (LIBS) and highlight their use in the analysis of stone diseases. We have summarized work done on gallstones and kidney stones using these advanced techniques particularly over the last 10 years. We have also briefly elaborated the basics of stone formations inside the human body and their complications for a better understanding of the subject.

Gallstone Magnesium Distributions from Optical Emission Spectroscopy

This work reports measurements of calcified gallstone elemental compositions using laser-induced optical emission spectroscopy. The experimental results support the importance of the magnesium concentration in gallstone growth. Granular stones reveal an increased magnesium concentration at the periphery of the granules, suggesting the inhibition of further growth. Non-granular gallstones reveal lower overall magnesium concentrations, but with higher values near the center.

Analysis of bakery products by laser-induced breakdown spectroscopy

In this study, we focused on the detection of Na in bakery products by using laser-induced breakdown spectroscopy (LIBS) as a quick and simple method. LIBS experiments were performed to examine the Na at 589 nm to quantify NaCl. A series of standard bread sample pellets containing various concentrations of NaCl (0.025-3.5%) were used to construct the calibration curves and to determine the detection limits of the measurements. Calibration graphs were drawn to indicate functions of NaCl and Na concentrations, which showed good linearity in the range of 0.025-3.5% NaCl and 0.01-1.4% Na concentrations with correlation coefficients (R(2)) values greater than 0.98 and 0.96. The obtained detection limits for NaCl and Na were 175 and 69 ppm, respectively. Performed experimental studies showed that LIBS is a convenient method for commercial bakery products to quantify NaCl concentrations as a rapid and in situ technique.

Laser-induced breakdown spectroscopy (LIBS): an overview of recent progress and future potential for biomedical applications

The recent progress made in developing laser-induced breakdown spectroscopy (LIBS) has transformed LIBS from an elemental analysis technique to one that can be applied for the reagentless analysis of molecularly complex biological materials or clinical specimens. Rapid advances in the LIBS technology have spawned a growing number of recently published articles in peer-reviewed journals which have consistently demonstrated the capability of LIBS to rapidly detect, biochemically characterize and analyse, and/or accurately identify various biological, biomedical or clinical samples. These analyses are inherently real-time, require no sample preparation, and offer high sensitivity and specificity. This overview of the biomedical applications of LIBS is meant to summarize the research that has been performed to date, as well as to suggest to health care providers several possible specific future applications which, if successfully implemented, would be significantly beneficial to humankind.

Investigation of common Indian edible salts suitable for kidney disease by laser induced breakdown spectroscopy

Salt is an essential and important dietary mineral for maintaining life. Currently, the issue of the potential benefit or damage from salt intake in chronic kidney disease patients is controversial. The attempt of this article is to bring into focus the potential role of elements particularly sodium, Na, and potassium, K, which are the main constituents of dietary salts, in kidney patients by using laser-induced breakdown spectroscopy (LIBS). LIBS spectra of different salt samples have been recorded in the spectral region 200-500 nm with spectral resolution 0.1 nm and in the spectral region 200-900 nm with spectral resolution 0.75 nm. Quantitative elemental study was carried out to determine the constituents of different types of common Indian edible salts by using the calibration-free LIBS method. Our experimental results demonstrate that Saindha salt (commonly known as rock salt) is more beneficial than other edible salts for patients suffering from chronic kidney disease. The results of the quantitative elemental analysis of the salts obtained from LIBS measurements are also compared to atomic absorption spectroscopy (AAS).