Heavy metals are recently introduced in the manufacturing of various household utensils. The objective of this study was to investigate different heavy metals contents in the composition of yogurts containers collected from the markets of Erbil City. The collected containers were aluminum containers and plastic containers with several colors. An inductively coupled plasma optical emission spectrometer was used to analyse the contents of nine heavy metals including cadmium, cobalt, chromium, copper, iron, lead, manganese, nickel, and zinc. The level of total detected metal load found in the analyzed containers. The recorded level for total detected metal load in the overall aluminum containers sample was very high and approximately 27 times more than that level in the overall plastic containers sample. Lead and cadmium were known as toxic heavy metals and detected with a high amount in the aluminum containers composition. The total contamination in the aluminum containers composition was noticeably exceeded the permissible world limits for heavy metals in packaging materials. Results obtained clarified that the white color of plastic containers is more preferable and safer than the dark or other multi-color plastic containers items in terms of heavy metals. KEY WORDS: Aluminum and plastic container, Heavy metal, ICP-OES, Yogurt Bull. Chem. Soc. Ethiop. 2024, 38(6), 1509-1519. DOI: https://dx.doi.org/10.4314/bcse.v38i6.1

An android smartphone-based Digital Image Colorimeter (DIC) was proposed as a simple, fast, portable, an environmentally friendly, and accurate analytical procedure for quantitative detection of acid fuchsine dye in aqueous solutions. In this study, light-boxes photography was recommended for the quantitative assessment and constructed utilizing built-in-house analytical device supported by smartphone. An application called Color Grab App was developed for the Android smartphone that uses an image-matching algorithm to assess the AFD solutions. The color values such as red (R), green (G), and blue (B) parameters can be measured via the app and utilized for determining the examined AFD solutions. The influence of main factors, such as light-boxes component, distance of sample cell holder, lighting types, position, angle, and power were studied in detail to obtain the correct color of the AFD solution and optimum conditions for recording the real RGB value. Under optimal conditions, the obtained calibration curves were linear over the ranges 3–9, 3–100, and 3–20 µg mL−1 of AFD with a good correlation coefficient (R2 > 0.99) due to using G, B, and the sum of GB channels, respectively. The obtained signal via a G channel presented greater sensitivity and linearity, therefore preferred to be the best working channel for the AFD assessment. The accuracy and precision of the proposed method were also in acceptable range. UV–Vis spectrophotometry was also utilized as reference method. The proposed method was successfully applied for the evaluation of the dye decolorization levels via Pseudomonas Aeruginosa BCH bacterium strain. It has been observed that the recorded results by the proposed methods are in a good agreement with those recorded by the reference method. The proposed method also provides budgetary advantages due to the use of low-cost and easy-handled device.

An android smartphone-based digital image colorimeter was proposed as a novel, fast, cheap, and portable colorimetric sensor for quantification of safranin in aqueous solutions via built-in-house light-boxes photography. Smartphone application known as RGB color detector app that uses an image-matching algorithm via using of take photo (TP) and live camera (LC) to analyze colorful solutions. The color values including red (R), green (G), and blue (B) parameters can be measured with the aid of the app and used for quantifying colorful solutions. The influence of various experimental factors has been optimized. Under optimal conditions, analytical curves were 1.0-10.0 and 2.0-30.0 µg/mL of safranin using G and B parameters, respectively. The obtained signal via the G channel also presented greater sensitivity and linearity, therefore preferred to be the best working channel. The obtained linear range, correlation coefficient, limit of detection, and limit of quantification were 1.00-10.00 µg/mL, 0.9889, 0.15 µg/mL, and 0.51 µg/mL via the GTP-25 method, and 1.00-10.00 µg/mL, 0.9961, 0.13 µg/mL, and 0.44 µg/mL via GLC-25 method, respectively. The proposed method was successfully applied for evaluation of the dye removal. Results were in good agreement with those recorded by UV-Visible spectrophotometer/reference method. KEY WORDS: Smartphone, App, Portable, Colorimetric, Sensor, Safranin Bull. Chem. Soc. Ethiop. 2023, 37(5), 1065-1080. DOI: https://dx.doi.org/10.4314/bcse.v37i5.1

Four rapid, accurate and very simple derivative spectrophotometric techniques were developed for the quantitative determination of binary mixtures of estradiol (E2) and progesterone (PRG) formulated as a capsule. Method I is the first derivative zero-crossing technique, derivative amplitudes were detected at the zero-crossing wavelength of 239.27 and 292.51 nm for the quantification of estradiol and 249.19 nm for Progesterone. Method II is ratio subtraction, progesterone was determined at λmax 240 nm after subtraction of interference exerted by estradiol. Method III is modified amplitude subtraction, which was established using derivative spectroscopy and mathematical manipulations. Method IIII is the absorbance ratio technique, absorbance of both medicines was measured at two wavelengths λ1= 260, -absorptive point and λ2=240max of progesterone. The Q equations were used to calculate the final concentrations. The calibration curve is linear from 5.0–140 and 2.0–32.0 µg/ml for estradiol and progesterone respectively. The proposed techniques' selectivity was tested using synthetic combinations created in the lab and assessed using the standard addition method. Using one-way ANOVA, the outputs of the proposed ways were compared, and the result showed no significant differences between the proposed techniques.

Microcrystalline cellulose (MCC) was isolated from the almond shell after its pretreatment with an acidic deep eutectic solvent (DES) of choline chloride/oxalic acid under microwave irradiation. The Fourier transform infrared spectroscopy analysis showed that the spectrum of the isolated (MCC) includes an additional peak at 1747.0 cm−1 which refers to the (C=O) esters and carboxylic peak. This indicates that the MCC surface has undergone simultaneous partial esterification during the isolation process. Owing to its favorable structural and morphological properties, the isolated MCC was successfully employed for the adsorption of aqueous Pb2+ ions with (50 mg/g) efficiency using a 3.0 g/L adsorbent dose at pH (6.5) and 20 °C. The adsorption was spontaneous near the ambient temperature, pH dependent, and exothermic. The Coulomb forces are the foremost adsorption driving force. The reusing of the spent DES and adsorbent for four successive rounds, affirmed their applicability on industrial scales.