Possibility of Thyroidism Diagnosis by Laser Induced Breakdown Spectroscopy of Human Fingernail

INTRODUCTION: A modern technique for elemental analysis of biological samples is laser induced breakdown spectroscopy (LIBS). This technique is based on emission of excited atoms, ions, and molecules in plasma produced by focusing a high power laser pulses on sample surface. Because of several advantages of LIBS including little or no sample preparation; minimally invasive; fast analysis time and very easy to use, in this study, this method was used for investigating the mineral content of fingernails. As the trace element of nail can be changed by several pathological, physiological, and environmental factors, we analyze the human fingernails to evaluate the possibility of thyroidism diagnosis.METHODS: A Q-switched Neodymium-Doped Yttrium Aluminium Garnet (Nd:YAG) laser operating at wavelength of 1064 nm, pulse energy of 50 mJ/pulse, repetition rate of 10 Hz and pulse duration of 6 ns was used in this analysis. Measurements were done on 28 fingernails belonging to 5 hypothyroid, 2 hyperthyroid and 21 normal subjects. For classification of samples into different groups based on thyroid status, a discriminant function analysis (DFA) was used to discriminate among normal and thyroidism groups.RESULTS: The elements detected in fingernails with the present system were: Al, C, Ca, Fe, H, K, Mg, N, Na, O, Si, Sr, Ti as well as CN molecule. Classification in two groups of normal and patient subjects and also in three groups of normal, hyperthyroid and hypothyroid subjects shows that 100% of original grouped cases were correctly classified. So, efficient discrimination among these groups is demonstrated.CONCLUSION: It is shown that laser-induced breakdown spectroscopy (LIBS) could be a possible technique for the analysis of nail and therefore identification of health problems

Qualitative analysis of teeth and evaluation of amalgam elements penetration into dental matrix using laser induced breakdown spectroscopy

In this study, laser induced breakdown spectroscopy (LIBS) is used for qualitative analysis of healthy and carious teeth. The technique of laser ablation is receiving increasing attention for applications in dentistry, specifically for the treatment of teeth such as drilling of micro-holes and plaque removal. In the process of ablation a luminous micro-plasma is normally generated which may be exploited for on-line elemental analysis via laser induced breakdown spectroscopy technique. We propose laser induced breakdown spectroscopy as a rapid, in situ and easy method for monitoring drilling process. The results of elemental analysis show the presence of some trace elements in teeth including P, Ca, Mg, Zn, K, Sr, C, Na, H, O and the permeability of some amalgam (teeth filling materials) elements including Hg, Ag, Cu and  Sn into dental matrix. This study address the ability of LIBS in elemental analysis of teeth and its feasibility in acute identification of healthy and carious teeth during drilling process for future clinical applications

Feasibility Study on Discrimination of Neo-plastic and Non-Neoplastic Gastric Tissues Using Spark Discharge Assisted Laser Induced Breakdown Spectroscopy

Introduction: The present work is a novel in vitro study that evaluated the possibility of diagnosing neoplastic from nonneoplastic gastric tissues using spark discharge assisted laser induced breakdown spectroscopy (SD-LIBS) method.Methods: In these experiments, the low energy laser pulses ablated a tiny amount of tissue surface leading to plasma formation. Then, a spark discharge was applied to plasma in order to intensify the plasma radiation. Light emission from plasma was recorded as spectra which were analyzed. Gastric tissues of 5 people were studied through this method.Results: The SD-LIBS technique had the potential to discriminate normal and cancerous tissues based on the significant differences in the intensities of some particular elements. The comparison of normalized calcium (Ca) and magnesium (Mg) peaks of neoplastic and nonneoplastic gastric tissues could be viewed as a practical measure for tissue discrimination since Ca and Mg peaks in spectra of neoplastic were noticeably higher than nonneoplastic.Conclusion: Considering the identification of gastric cancer, the applied method in these experiments seems quite fast, noninvasive and cost-effective with respect to other conventional methods. The significant increment of specific Ca and Mg lines of neoplastic gastric tissues in comparison to the nonneoplastic ones can be considered as valuable information that might bring about tissue classification. The number of samples in this work, however, was not sufficient for a decisive conclusion and further researches is needed to generalize this idea

Architecting functionalized carbon microtube/carrollite nanocomposite demonstrating significant microwave characteristics

Abstract Biomass-derived materials have recently received considerable attention as lightweight, low-cost, and green microwave absorbers. On the other hand, sulfide nanostructures due to their narrow band gaps have demonstrated significant microwave characteristics. In this research, carbon microtubes were fabricated using a biowaste and then functionalized by a novel complementary solvothermal and sonochemistry method. The functionalized carbon microtubes (FCMT) were ornamented by CuCo2S4 nanoparticles as a novel spinel sulfide microwave absorber. The prepared structures illustrated narrow energy band gap and deposition of the sulfide structures augmented the polarizability, desirable for dielectric loss and microwave attenuation. Eventually, the architected structures were blended by polyacrylonitrile (PAN) to estimate their microwave absorbing and antibacterial characteristics. The antibacterial properties against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) were scrupulously assessed. Noteworthy, the maximum reflection loss (RL) of the CuCo2S4/PAN with a thickness of 1.75 mm was 61.88 dB at 11.60 GHz, while the architected FCMT/PAN composite gained a broadband efficient bandwidth as wide as 7.91 GHz (RL > 10 dB) and 3.25 GHz (RL > 20 dB) with a thickness of 2.00 mm. More significantly, FCMT/CuCo2S4/PAN demonstrated an efficient bandwidth of 2.04 GHz (RL > 20 dB) with only 1.75 mm in thickness. Interestingly, FCMT/CuCo2S4/PAN and CuCo2S4/PAN composites demonstrated an electromagnetic interference shielding efficiency of more than 90 and 97% at the entire x and ku-band frequencies, respectively

Biocontrol of pigeon tick Argas reflexus (Acari: Argasidae) by entomopathogenic fungus Metarhizium Anisopliae (Ascomycota: Hypocreales)

The pigeon tick Argas reflexus is a pathogen-transmitting soft tick that typically feeds on pigeons, but can also attack humans causing local and systemic reactions. Chemical control is made difficult due to environmental contamination and resistance development. As a result, there is much interest in increasing the role of other strategies like biological control. In this study, the efficacy of three strains (V245, 685 and 715C) of entomopathogenic fungus Metarhizium anisopliae for biological control of three life stages of pigeon tick A. reflexus including eggs, larvae, engorged and unfed adults was investigated under laboratory conditions. Five concentrations of different strains of M. anisopliae ranging from 10³ to 10(7) conidia/ml were used. All fungal strains significantly decreased hatchability of A. reflexus eggs. Strain V245 was the most effective strain on the mortality of larval stage with nearly 100% mortality at the lowest concentration (10³ conidia/ml) at 10 days post-inoculation. The mortality rate of both engorged and unfed adult ticks were also increased significantly exposed to different conidial concentrations compared to the control groups (P < 0.05) making this fungus a potential biological control agent of pigeon tick reducing the use of chemical acaricides

Rapid and cost-effective quantitative analysis of arsenic in drinking water using surface-enhanced Raman spectroscopy

A rapid, cost-effective, and sample-preparation-free approach is proposed for the quantitative detection of arsenic in drinking water, using surface-enhanced Raman spectroscopy (SERS). This fabrication entailed comprehensive optimization of chemically synthesized silver colloidal nanoparticles, focusing on parameters such as centrifugation time and speed to attain maximal nanoparticle concentration while mitigating interference from trisodium citrate and other chemical agents. Subsequently, SERS substrates were fabricated by depositing a concentrated drop of colloidal silver nanoparticles onto hydrophobic silicon substrates using the drop-coating technique. The drying process induced a coffee-ring effect, resulting in a pronounced spatial variation of nanoparticle concentration, with significantly higher densities observed in the peripheral ring regions compared to the central regions of the substrate. These regions possess the ability to enhance the Raman spectrum of arsenic, enabling the detection of arsenic at concentrations as low as 50 ppb. This method can prove highly valuable for initial field analyses of drinking water