New Analytical Strategy for Bioaccessibility Evaluation of Bromine and Iodine from Edible Seaweeds.

A strategy for determining the bioaccessibility of bromine and iodine from edible seaweeds was proposed for the first time using microwave-induced combustion (MIC) and ion chromatography coupled to mass spectrometry (IC-MS) after in vitro digestion. The concentrations of bromine and iodine in edible seaweeds using the proposed methods (MIC and IC-MS) were not statistically different from those using MIC and inductively coupled plasma mass spectrometry (p > 0.05). Trueness was assessed by recovery experiments (101-110%, relative standard deviation <10%). Following an in vitro digestion protocol, MIC was proposed as sample preparation for bioaccessible and residual fractions. Using this strategy, the mass balance totaled from 97 to 111%. No statistical difference (p > 0.05) was observed between the total concentration of bromine or iodine and their concentration in bioaccessible and residual fractions for three edible seaweed species, indicating full analyte quantification in the fractions.

Advances in the Understanding of Oxaliplatin-Induced Peripheral Neuropathy in Mice: 7-Chloro-4-(Phenylselanyl) Quinoline as a Promising Therapeutic Agent.

In this study, the deposition of platinum in oxaliplatin (OXA)-exposed mice and the effects of the oxidative damage on the central nervous system were investigated. The relationship between the reactive species (RS) levels as well as the expression and activity of enzymes, such as catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD) and acetylcholinesterase (AChE), in the development of peripheral neuropathy after OXA exposure, was evidenced. The effects of 7-chloro-4-(phenylselanyl) quinoline (4-PSQ) on OXA-induced peripheral neuropathy was also investigated. Swiss mice received OXA (10 mg kg-1) or vehicle by intraperitoneal route (days 0 and 2). Oral administration of 4-PSQ (1 mg kg-1) or vehicle was performed on days 2 to 14. Behavioural tasks started on day 9, after the first OXA administration. It was observed that 4-PSQ reduced the mechanical and thermal hypersensitivity induced by OXA. 4-PSQ and OXA did not affect locomotor and exploratory activities. The results revealed, for the first time, a high concentration of platinum in the spinal cord of mice exposed to OXA. 4-PSQ reversed the increased levels of RS in the spinal cord, cerebral cortex and hippocampus of mice exposed to OXA. The alterations in the activity and expression of the GPx, SOD, CAT and AChE induced by OXA exposure were normalized by 4-PSQ. Therefore, the 4-PSQ might be a good prototype for the development of a more effective drug for the treatment of OXA-induced peripheral neuropathy. The results obtained by the present study expanded the knowledge about the mechanisms involved in the physiopathology of peripheral neuropathy. Graphical abstract.

A selective volatilization method for determination of chloride and sulfate in calcium carbonate pharmaceutical raw material and commercial tablets.

In this work a feasible method for chloride and sulfate determination in calcium carbonate pharmaceutical raw material and commercial tablets by ion chromatography after microwave-induced combustion was developed. The analytes were released from matrix by combustion in closed system pressurized with oxygen. Starch as volatilization aid, 100mmolL-1 HNO3 as absorbing solution and 5min of microwave irradiation time were used. Recovery tests using standard solutions were performed for the accuracy evaluation. A mixture of calcium carbonate pharmaceutical raw material or commercial tablets, starch and a certified reference material was also used as a type of recovery test. Recoveries ranging from 88% to 103% were obtained in both spike tests. Limits of detection (Cl-: 40µgg-1 and SO42-: 140µgg-1) were up to eighteen times lower than the maximum limits established for the analytes by Brazilian, British, European and Indian Pharmacopoeias. The limit tests recommended by the European Pharmacopoeia for Cl- and SO42- in CaCO3 were carried out to compare the results. Chloride and SO42- concentrations in the samples analyzed by proposed method were in agreement with those results obtained using the tests recommended by the European Pharmacopoeia. However, the proposed method presents several advantages for the routine analysis when compared to pharmacopoeial methods, such as the quantitative simultaneous determination, high sample preparation throughput (up to eight samples per run in less than 30min), reduced volume of reagents and waste generation. Thus, the proposed method is indicated as an excellent alternative for Cl- and SO42- determination in CaCO3 pharmaceutical raw material and commercial tablets.

A novel and eco-friendly analytical method for phosphorus and sulfur determination in animal feed.

An eco-friendly method for indirect determining phosphorus and sulfur in animal feed by ion chromatography was proposed. Using this method, it was possible to digest 500 mg of animal feed in a microwave system under oxygen pressure (20 bar) using only a diluted acid solution (2 mol L-1 HNO3). The accuracy of the proposed method was evaluated by recovery tests, by analysis of reference material (RM) and by comparison of the results with those obtained using conventional microwave-assisted digestion. Moreover, P results were compared with those obtained from the method recommended by AOAC International for animal feed (Method nr. 965.17) and no significant differences were found between the results. Recoveries for P and S were between 94 and 97%, and agreements with the reference values of RM were better than 94%. Phosphorus and S concentrations in animal feeds ranged from 10,026 to 28,357 mg kg-1 and 2259 to 4601 mg kg-1, respectively.