In recent years, ultrasound-assisted extraction (UAE) has attracted growing interest, as it is an effective method for the rapid extraction of a number of compounds from food and environmental samples, with extraction efficiency comparable to that of classical techniques. In particular, recently, numerous analytical applications of this technique dealt with the extraction of natural compounds and pollutants from food and environmental samples. This review gives a brief presentation of the theory of UAE, discusses recent advances that influence its efficiency, and summarizes the main results in selected applications published in the period 2010–12. There is discussion of the advantages and the disadvantages of UAE and the possibility of coupling UAE with other analytical techniques.

Ultrasound-assisted extraction for food and environmental samples

Laser-induced breakdown spectroscopy for analysis of plant materials: A review

Determination of trace element concentrations in tomato samples at different stages of maturation by ICP OES and ICP-MS following microwave-assisted digestion

Multi-element coprecipitation for separation and enrichment of heavy metal ions for their flame atomic absorption spectrometric determinations

A solid phase extraction procedure for the determination of Cd(II) and Pb(II) ions in food and water samples by flame atomic absorption spectrometry.

The present article gives an overview of recent publications and modern techniques of sample preparation for food analysis employing atomic and inorganic mass spectrometric techniques, such as flame atomic absorption spectrometry, chemical vapor generation atomic absorption and atomic fluorescence spectrometry, graphite furnace atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry, and inductively coupled plasma mass spectrometry. Among the most frequently applied sample preparation techniques for food analysis are dry ashing, usually with the addition of an ashing aid, and acid digestion, preferably with the assistance of microwave energy. Slurry preparation, particularly with the assistance of ultrasound, is increasingly used to reduce acid consumption and sample preparation time. Direct analysis of solid samples is gaining importance in the field of food analysis as it offers the highest sensitivity, avoids the use of acids and other aggressive reagents, make...

Sample Preparation for the Determination of Metals in Food Samples Using Spectroanalytical Methods—A Review

A comparison of flow injection methods for sulfide determination based on phenothiazine dyes produced from diverse aromatic amines

An Interdisciplinary Approach to Evaluate the Mobility and Toxicity of Cadmium in a Soil–Plant System

A spectrophotometric flow analysis procedure to determine Captopril (CPT) and N-acetyl-L-cysteine (NAC) in pharmaceutical formulations was developed based on the reaction with iminoquinone radical produced from the N,N-dimethyl-p-phenilenediamene (DMPD) oxidation in acid medium. The reagents addition order was evaluated and analytical parameters were optimized. The linear concentrations ranges were 2.5-90 and 5.0-50 mg L-1 for CPT and NAC, respectively. Limits of detection (3σ) were calculated at 0.22 and 1.8 mg L-1 and the relative standard deviation (N = 10) were lower than 1.0 and 2.1% for CPT and NAC, respectively. The procedure was employed for CPT and NAC determination in diverse pharmaceutical formulations and by applying paired t-test the results were in agreement with those obtained by reference methods for 95% confidence level.

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Eduardo Batista Guimarães Nunes dos Santos

Papers

Sample Preparation for the Determination of Metals in Food Samples Using Spectroanalytical Methods—A Review

A comparison of flow injection methods for sulfide determination based on phenothiazine dyes produced from diverse aromatic amines

An Interdisciplinary Approach to Evaluate the Mobility and Toxicity of Cadmium in a Soil–Plant System

Exploiting iminoquinone free radical production for thiol based drugs determination in pharmaceutical formulations