Development of a vortex-assisted switchable-hydrophilicity solvent-based liquid phase microextraction for fast and reliable extraction of Zn (II), Fe (II), Pb (II), and Cd (II) from various baby food products

This manuscript describes the development of a novel liquid phase microextraction (LPME) method for the extraction and determination of Zn (II), Fe (II), Pb (II), and Cd (II) in various infant/baby food and supplements products. The method is based on vortex-assisted extraction combined with a switchable-hydrophilicity solvent (SHS) sample preparation. The SHS, which undergoes reversible phase changes triggered by pH change, enables selective extraction and easy phase separation. A flame atomic absorption spectroscopy was used in the final determination step. Optimization studies revealed, that the optimal pH of the sample solution (after digestion) during analytes extraction is 5.5. A l-proline is added to the sample (375 mM) to ensure the complexation of the target metal cations. After the complexation step, 750 µL of SHS - a N, N-Dimethylcyclohexylamine along with 0.9 mL of 2 M of acetic acid solution is added (hydrophilicity switch-on stage) and mixed manually to obtain a homogeneous solution. In the last stage, 0.45 mL of 10 M NaOH solution (hydrophilicity switch-off stage) is added to the sample solution and a vortex for 100 s is applied to ensure the effective extraction and separation of the complex containing the analytes. At this stage, a cloudy solution is immediately obtained. Finally, the effective phase separation is obtained at the centrifugation step (4000 rpm for 2 mins). The method limit of detection was as 0.03, 0.009, 0.6, and 0.2 ng/L for Zn (II), Fe (II), Cd (II), and Pb (II) respectively with RSD% below 2.0 %. The analysis of certified reference materials and real samples proved the full applicability of the method for routine analysis, contributing to the field of heavy metal analysis and ensuring the safety of baby products. According to the AGREE methodology, this method can be named as green analytical chemistry method with a score of 0.77.

An air-assisted dispersive liquid phase microextraction method based on a hydrophobic magnetic deep eutectic solvent for the extraction and preconcentration of melamine from milk and milk-based products

In the current research, a fast and sustainable air-assisted hydrophobic magnetic deep eutectic solvent-based dispersive liquid phase microextraction followed by UV-Vis spectrophotometry measurements was optimized for the extraction and determination of melamine in milk and milk-based products. The central composite design was applied for the optimization of factors affecting the recovery of melamine. Quantitative extraction of melamine was achieved using hydrophobic magnetic deep eutectic solvents prepared from a mixture of octanoic acid, aliquat-336, and cobalt(II) chloride. The optimum conditions for extraction were found as follows: 6 extraction cycles, pH 8.2, extraction solvent volume 260 µL, and acetone volume 125 µL.Interestingly, a centrifugation step was not required to achieve phase separation. Under the optimum conditions, melamine was determined in the linear range of 3-600 ng mL^-1, the limit of detection (3S_blank/m) of 0.9 ng mL^-1, and the enrichment factor of 144. The validation of the method was investigated by the analysis of reference materials. Consequently, the method was successfully applied for the analysis of melamine residues in milk and milk-based products.

Effective UO22+ removal from aqueous solutions using lichen biomass as a natural and low-cost biosorbent

The UO₂²⁺ biosorption properties of a lichen, Evernia prunastri, from aqueous solutions were investigated. The widely occurring lichen samples were collected from the forest in Bilecik-Turkey. The UO₂²⁺ biosorption onto lichen was characterized by FT-IR and SEM-EDX analysis techniques before and after biosorption. The effects of the solution pH, biosorbent dosage, UO₂²⁺ concentration, contact time, and temperature on UO₂²⁺ biosorption on lichen sample were studied by using the batch method. The isotherm experimental data were described using isotherm models of Langmuir, Freundlich and Dubinin Radushkevich. The maximum UO₂²⁺ biosorption capacity of the lichen sample was estimated by the Langmuir equation to be 0.270 mol kg^-1. The adsorption energy from the Dubin Radushkevich model was found to be 8.24 kJ mol^-1. Kinetic data determined that the biosorption was best described by the pseudo-second-order kinetic model. Thermodynamic findings showed that the biosorption process was endothermic, entropy increased and spontaneous. In conclusion, the lichen appears to be a promising biosorbent for the removal of UO₂²⁺ ions from aqueous solutions because of high biosorption capacity, easy usability, low cost, and high reusability performance.

Evaluation of insulin resistant diabetes mellitus in Alström syndrome: a long-term prospective follow-up of three siblings

Alström syndrome is a rare cause of diabetes mellitus. We studied two generations of a Turkish family in whom four members were affected by Alström syndrome. The natural course of the syndrome in three sisters was followed for 13 yr. The three sisters had short stature and truncal obesity, and developed complete blindness due to retinitis pigmentosa at 10, 5 and 13 yr of age. Two had sensorineural hearing loss and mild mental retardation, while the other developed diabetic ketoacidosis (DKA) at 14 yr and was treated with insulin from onset of diabetes. In the second case, diagnosis of diabetes was made by an OGTT at age 20 yr, and controlled with diet alone for 11 yr, then with a sulphonylurea for 2.5 yr, then with insulin. The third case developed acute hyperglycaemia at 20 yr, and required insulin from onset. Moreover, transitional features of impaired carbohydrate and fat metabolism (severe hyperinsulinaemia and insulin resistance progressing to islet beta cell failure, and hypertriglyceridaemia with fatty liver) were demonstrated, in accord with the literature. Previously unreported findings characteristic of nephro-uropathy with early-onset hypertension were also detected, and included in all cases proteinuria, glomerulopathy, and abnormal locations of the kidneys, narrowed uretero-renal junctions and dilated ureters.

A retrospective analysis of thyroid cancer

We reviewed the results of 2071 thyroidectomies performed during the past 11 years at Uludağ University School of Medicine Hospital. Of all the patients 1602 (77.4%) were women and 469 (22.6%) were men (F:M = 3.4:1). Seventy-eight of the thyroid surgery patients (3.77%) had thyroid carcinoma, with a female to male ratio of 2.0:1. The relative risk of thyroid cancer in male versus female patients with thyroid nodules was determined to be 1.75:1. Patient distribution by thyroid carcinoma type was: papillary carcinoma 49%, follicular carcinoma 24%, undifferentiated carcinoma 10%, metastatic carcinoma 10%, and medullary carcinoma 6%. Fine needle aspiration biopsy (FNAB) has been used routinely in our hospital for the last 4 years. During this period, the average number of operations decreased from 201 to 130 per year and the surgical diagnosis of thyroid carcinoma increased from 2.85 to 7.65%. We conclude that papillary carcinoma is relatively less prevalent in our population and that fine needle aspiration biopsy is the preferred method of diagnosing nodular thyroid disease.