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Thin-Layer Chromatography in Food Analysis
Published in Bernard Fried, Joseph Sherma, Practical Thin-Layer Chromatography, 2017
The crude sample extract may be subjected directly to cleanup without prior clarification. Different procedures, such as liquid-liquid partitioning or column cleanup, can be used to purify the sample extract. Liquid-liquid partitioning is often carried out in a separatory funnel. A partition system is manipulated by changing the nature of the two liquid phases, generally through the addition of solvents or buffers. In these cases, the more polar liquid is generally water, and its tendency to dissolve solutes can be changed by adding salts (to produce a salting-out effect) or buffers (to dissolve ionic materials such as amino acids). The less polar phase of a partition system is generally an organic solvent, and its ability to dissolve solutes can be varied by adding more or less polar solvents.
Reactivity trends for mechanochemical reductive coupling of aryl iodides
Published in Green Chemistry Letters and Reviews, 2023
Courtney Carson, Joshua Hassing, Trinity Olguin, Karl P. Peterson, Rebecca A. Haley
To a 15-mL stainless-steel reaction jar was added 5 stainless-steel balls, followed by the addition of 3a (250 mg, 0.919 mmol), anhydrous NiCl2 (11.9 mg, 0.0919 mmol), 2,2′-bipyridine (14.4 mg, 0.0919 mmol), a Mn shot (101 mg, 1.84 mmol), and the desired amount of dimethyl carbonate (0, 0.10, 0.5, or 1 equivalent) was added. The jar was then closed and sealed with parafilm and secured in the ball mill. The reaction was run at 18 Hz for 16 h. The resulting reaction mixture was washed with approximately 15 mL of ethyl acetate and centrifuged for 2 min at 4000 rpm to separate the Mn powder from the organic supernatant. The supernatant was decanted into a separatory funnel where water was added for liquid–liquid extraction. The organic layer was dried over MgSO4, and the solvent was removed using a rotary evaporator to reveal a white solid.
Synthesis and characterization of azidated Adenopus breviflorus benth seed oil
Published in Green Chemistry Letters and Reviews, 2020
T. Akintayo Emmanuel, O. Akintayo Cecilia, I. O. Oluwaleye, O. Ajaja, S. Beuermann
To 10 mL of deionized water in a 50 mL round-bottom flask, 10.2 g of [Hmim]BF4− and 5.5 g of EADBO was added. To this, 0.98 g (15 mmol) NaN3 dissolved in 10 mL water was added while stirring continuously and heated at 65°C for two and half days. The mixture was cooled to room temperature and extracted twice with ethyl acetate in a separatory funnel. The combined ethyl acetate extract was successively washed with saturated sodium chloride solution and water, dried over anhydrous Na2SO4 and filtered. The solvent was evaporated using a rotary evaporator. The product showed the following IR frequencies (KBr film cm−1): 3450 (CH OH), 2100 (CH N3), and 1747 (CH2COO−).
Comparison of total phenols, flavonoids and antioxidant potential of local and imported ripe bananas
Published in Egyptian Journal of Basic and Applied Sciences, 2018
Fatma Said Al Amri, Mohammad Amzad Hossain
The dried coarse powdered banana samples (500 gm) were extracted separately with methanol (2 L) by using the maceration method for several days. It was filtered and again reextracted by the same solvent for complete extraction. Both extracts were mixed and evaporated the methanol to give methanol extract (35.08 gm). It was dissolved in distilled water (300 ml) and transfer to the separatory funnel and portioned by n-hexane, chloroform, ethyl acetate and n-butanol solvents [13]. Repeated the fractionation twice and combined. The different polarity fractions were dried by using a rotary evaporator to give n-hexane, chloroform, ethyl acetate, n-butanol and water crude extract. The obtained different extracts were used for the determination of the amount of phenols and flavonoids content and antioxidant potential.