Doehlert design in the optimization of ultrasound assisted dissolution of fish fillet samples with tetramethyl ammonium hydroxide for metals determination using FAAS

Determination of trace heavy metal elements in litterfall by inductively coupled plasma optical emission spectrometry after extraction using choline chloride-based deep eutectic solvents

“…Like the other plant-based samples, the determination of heavy elements in litterfall requires their pre-treatment in order to transfer the analytes to an aqueous phase compatible with spectroscopic instruments. Several pretreatment methods have been developed for the extraction of metals from complex matrices, such as dry ashing, 4 wet digestion, 5 microwave digestion, 6 and ultrasound-assisted dissolution. 7 The most commonly employed sample pretreatment procedures are typically based on the digestion of the sample in a mixture of acid (typically concentrated sulphuric or nitric acid) and an oxidizing agent (such as hydrogen peroxide).…”

Key information related to quality by design (QbD) applications in analytical methods development

“…DoE can be used for several applications depending on issue to be solved. In a review paper, Hibbert [11] described the use of several DoE processes applied to chromatographic separation and highlighted the most used in optimization and validation studies such as: (1) Factorial design [12][13][14]; (2) Plackett-Burman (PB) design [15][16][17]; (3) Central Composite design (CCD) [18][19][20]; (4) Box-Behnken design (BBD) [21][22][23]; (5) Doehlert design (DD) [24][25][26] and (6) Mixture design [27][28][29]. Other types of DoE have been used and often cited in the literature, as examples Mixed-level fractional factorial design [30][31][32]; Definitive Screening design (DSD) [33][34][35] and D-optimal design [36][37][38].…”