Walid Tawfik

Laser-induced breakdown spectroscopy (LIBS) is one of the analytical techniques which has vast applications in the material analysis. We have applied LIBS technique for the elemental analysis to determine trace elements as impurities in polystyrene and polycarbonate polymer materials. These polymer samples were collected from one of the Saudi industries which are being used as containers for food and water. The study was carried out under high vacuum (1 × 10−5 mbar) using a 10 Hz Q-switched pulsed Nd:YAG laser at wavelength 1064 nm, 20 mJ energy and 8 ns pulse width to generate the plasma of the polymer samples. By analyzing the plasma plume emission, LIBS spectra revealed the existence of Al, Si, P, Ca, Mg, N in Polystyrene and Br, Mg, Ca, N in polycarbonate as trace elements. Molecular lines of CN, CO, C2 and CH in these samples have been observed as well. The presence of Al, Si, and P traces in these polymer samples might be harmful to the human body. LIBS is found to be a simple, non-contact, online and cost-effective method to identify the hazardous elements in polymers. The industries can adopt this method to provide harmless containers for water or food products. © 2019

Majority of the pharmaceutical tablets and capsules available at the medical stores are film-coated for taste masking and for protection against moisture and light. The elemental concentration of the film-coated content should be carefully monitored otherwise it can be toxic. In the present work, the toxicity of some commercial antidiabetic tablets available in Pakistan has been checked by precise quantitative analyses of their elemental content using a novel method. The proposed technique combines calibration free laser induced breakdown spectroscopy (CF-LIBS) and laser ablation time of flight mass spectrometer (LA-TOF-MS) without using aggressive chemicals. The thickness and chemical composition of coating films are analyzed using cross-sectional scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). It is observed that the film-coating on the German sugar cure cores (GSCC) tablets consist of aluminum (50–100) μm and titanium (500–800) μm. In addition, the thicknesses of Glucophage and Zolid Plus tablets’ coatings are found to range from 20–30 μm and composed of titanium, carbon, oxygen, sodium and magnesium. It has been found that a daily dose of three times a day of GSCC tablets contains about 600 mg/day of titanium and 150 mg/day of aluminum may considered toxic according to the United States food and drug administration (FDA). The results demonstrated that the core of the GSCC tablets mainly composed of calcium (60.7%), magnesium (24.2%), sodium (4.3%), potassium (2.5%), barium (2.4%) and silicon (5.8%) whereas, the core material in the Zolid Plus 850 mg and Glucophage 1000 mg tablets contain metformin (C4H11N5•HCl) with hydrogen (7.3%), carbon (29.1%), nitrogen (42.4%) and chlorine (21.2%). Inclusive analysis based on the innovated non-destructive methodology that combines CF-LIBS and LA-TOF-MS reveals that it can be used for direct monitoring the toxicity for quality assurance in the pharmaceutical industry of antidiabetic drugs in future. © 2020 Elsevier B.V.