Sonication extraction yield

Sonication in the presence of solvent is also an alternative, very effective procedure to maximize extraction yield. Ultrasonic agitation allows more intimate... 

Incubation of sonic extracts of several A. aerogenes bacterial strains with ATP, ribose 5-P, glutamine, and acetyl-P yielded an arylamine and an imidazole. When these incubations were performed with either ribose 5-P-l-Ci<, AMP-8-C, or adenine-2-C as an additional reactant, the arylamine and the imidazole accumulated in sufficient amounts to be isolated and identified. After purification the imidazole was shown to be... 

In aqueous simulants, the extraction yields for controls were lower than that of the samples in the same experimental scheme. A sonication treatment of the controls during the extraction led to extraction yields similar to that of the samples. Both samples and controls (as well as blanks were therefore subsequently sonicated in the extraction step, both in the cases of 15% ethanol and of 3% acetic acid, and for all time-temperature exposures. The yields from the extraction for the samples in aqueous solutions ranged from 70 to 100%. Yields of extraction were generally lower for the exposure of 1 hour at reflux temperature compared with 10 days at 40 °C. The analysis of the three additives from aqueous simulants is represented in Figure 6.8. The SML concentrations for the different compounds analysed was sufficient to yield reproducible peaks and quantitation. 

THF). The authors found that the yield could be increased to 95 % by sonication of the reaction vessel, for the reaction in THF. The ionic liquid was then used to extract the manganese by-products and impurities from an ethyl acetate solution of the product [63]. 

To a solution of red phosphorus (3.1 g, 0.1 mol) in DMSO (6 ml) the following was added successively potassium hydroxide (0.95 g, 17 mmol) in water (50 mmol) and aldehyde, 4-methylbenzaldehyde (0.90 g, 7.5 mmol). The reaction mixture was sonicated for 10 min, after which it was filtered to remove excess phosphorus. The filtrate was then acidified to pH = 2-3 with 37% aqueous HC1 and extracted with chloroform. The aqueous portion was concentrated to dryness, and the residue dissolved in a minimum of acetic acid. The supernatant layer was separated from the solid and concentrated to dryness to give the product a-hydroxy-p-methylbenzylphosphonous acid in 30% yield. 

Two studies compared sonication with Soxhlet extraction with pentane [13], acetone/hexane [13] and hexane/ispropyl alcohol (70 30) [5], The first two Soxhlet extraction solvents yielded lower recoveries than sonication, but the most polar solvent hexane/isopropyl alcohol gave recoveries and relative standard deviations for NP and NPE0i i9 comparable with sonication with hexane/acetone [5],... 

Method B (with sonication) Sonication of the Reissert compound (4.6 mmol), haloalkane (6.6 mmol), and TEBA-C1 (34 mg, 0.15 mmol) in CH,C1, (2.5 ml) and aqueous NaOH (50%, 1.8 ml) is conducted for 20 min. Work-up at this stage, as described in 6.2.30.A, yields the alkylated Reissert compound. Addition of EtOH (6 ml) and sonication for a further 30 min with subsequent work-up by addition of the mixture to 11,0 (20 ml) and extraction with CH,C1, (3 x 10 ml) produces the C-alkylated heteroarene, which is isolated as the hydrochloride salt (70-90%) by saturation of the dried organic extracts with HC1 gas. 

The Reissert compound (5.7 mmol), an aryl aldehyde and TEBA-C1 (14 mg, 0.06 mmol) in CH,C1, (3 ml) are sonicated with aqueous NaOH (50%, 2.5 ml) for 5 min. EtOH (8 ml) and CH,C1, (15 ml) are added and sonication is continued for a further 85 min and the mixture is then poured into H,0 (20 ml). The aqueous phase is separated and extracted with CH2C1, (3x10 ml). The combined organic solutions are dried (MgS04), concentrated to 20 ml, and saturated with HCI gas to yield the hydroxymethylheteroarene hydrochloride (80-99% ). 

The a,P-unsaturated ketone (10 mmol) is stirred with the nitroalkane (40 mmol), K,CO, (0.7 g) and Aliquat (40 mg, 0.1 mmol) and the mixture is subjected to sonication at room temperature until the reaction is complete, as shown by GLC. The mixture is acidified with HC1 (1M) and extracted with Et20 (3 x 20 ml). The dried (MgS04) extracts are evaporated to yield the nitro ketone (>70%). 

Method B (liquiddiquid conditions) PhSeCHCl2 (0.24 g, 1 mmol), the organic substrate (1.25 mmol), Aliquat (8.1 mg, 0.02 mmol) and aqueous NaOH (50%, 1.5 ml) are sonicated for 90 min at room temperature. H20 (30 ml) is added and the aqueous mixture is extracted with CH2C 2 (3 x 20 ml). The combined extracts are dried (MgS04) and evaporated to yield the product. 

SPE methods with different cartridge packings have been employed for the pre-concentration and clean up of sulfonated azo dyes from waters and soil extracts [110,111], The extraction of solid samples has been carried ont by sonication or Soxhlet extraction and the extracts treated like the water samples. C18 cartridges and columns [111] were used followed by the elution with aqueous organic solvents in the presence of TEA with recovery yields always greater than 65% [93,111], Higher recoveries have been obtained by using C18 columns, pre-conditioned with an ammonium acetate buffer and elnted with methanol [111], The use of styrene-divinylbenzene [93,112], as well as of cross-linked polymeric sorbents with sulfonate functions, was shown to be suitable in the SPE of the more polar componnds [111],... 

Lopez-Avila et al. [88] compared MAE, Soxhlet, sonication, and SFE in their ability to extract 95 compounds listed in the EPA method 8250. Freshly spiked soil samples and two SRMs were extracted by MAE and Soxhlet with hexane-acetone (1 1), by sonication with methylene chloride-acetone (1 1), and by SFE with supercritical carbon dioxide modified with 10% methanol. Table 3.16 shows the number of compounds in different recovery ranges obtained by the various techniques. Sonication yielded the highest recoveries, followed by MAE and Soxhlet, whose performances were similar. SFE gave the lowest recoveries. MAE demonstrated the best precision RSDs were less than 10% for 90 of 94 compounds. Soxhlet extraction showed the worst precision only 52 of 94 samples gave RSDs less than 10%. No technique produced acceptable recoveries for 15 polar basic compounds. The recoveries of these compounds by MAE with hexane-acetone at 115°C for 10 minutes (1000 W power) were poor. Consequently, their extraction with MAE was investigated using acetonitrile at 50 and 115°C. Ten of the 15 compounds were recovered quantitatively (>70%) at 115°C. 

Prior to total RNA extraction, sample lysis procedures have to be performed. Lysis conditions are very important for the success of the RNA extraction and depend strongly upon the sample used. Due to great diversity, the biological sample can be pulverized, homogenized, sonicated, or otherwise disrupted to yield a mixture that contains cells, subcellular components, and other biological debris in an aqueous buffer or suspension. Here is described the protocol for the Trizol method of RNA extraction. 

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