Introduction The purpose of this experiment was to purify acetanilide that was contaminated with relatively small amounts of impurities using recrystallization. The success of recrystallization was dependent on a suitable solvent being chosen and proper recrystallization technique being carried out. The solvent chosen had to have a different polarity than that of the molecule of interest. The technique used was dependent on the solubility of the solvent at higher temperature and the solubility of the impurities at all temperatures. To analyze the acetanilide product of the reaction, 1H NMR and IR were used.
Cerium nitrate hexahydrate (Ce(NO3)3∙6H2O), zirconium (IV) oxynitrate hydrate (ZrO(NO3)2∙xH2O), 1-butanol, nitric acid (HNO3) and P123 surfactant (EO20-PPO70-PEO20) were the required chemicals. The required amounts of cerium oxide and zirconium oxide precursors (see Annex 7.2 for the calculation details) were dissolved in a solution containing respective amounts of 1-butanol, HNO3 and P123 surfactant. Then, the solution was placed in a water bath of 40 to 60 oC under magnetic stirring for further mixing. The obtained gel was placed in the oven at 120 oC for 5 h. After, the powder was washed several times with ethanol and was filtered in order to recover the solids. The solids were then dried overnight.
Hanusaiodine solution, chloroform, aqueous KI solution, Na2S2O3 and starch solution is used. Iodine values are calculated from the difference between the blankaand the test sample. For peroxide value; solvent mixture (composed of glacial acetic acid and chloroform), saturated KI solution, starch solution and Na2S2O3 soluiton is used and peroxideavalues are calculated. A) Iodine Value: Hanus Method In this experiment, iodine value of sun floweraoil was determined with Hanusamethod. Blank solution and oil solution were prepared and stored in the dark.
pruriens seed extract and FeMPn were characterized with FTIR to determine the biomolecules contained in the extract that involved in the reaction to form FeMPn. The FTIR spectra of the extract and FeMPn are shown in Fig. 5. The FTIR spectrum of the extract showed a broad absorption band in an absorbance area of 3384.8 cm-1 that assigned to the overlapping of O-H stretching vibration of flavonoids, alkaloids, polyphenols, alcohols or water and N-H stretching vibration of amine compounds, due to the hydrogen bonding. The absorption band at 1627.8 cm-1 referred to C=C stretching vibration which is possible to be derived from aromatic ring in amino acid, while the absorption band in 1529.4 cm-1 referred to N-H bending vibration of amine which is possible to be derived from the L-dopa.
Further studies on this hydrolysis in the presence of some [CoLM(NCS)(OH)]n+ complexes where LM is the tetradentate macrocyclic ligand has been studied at pH 9 with I = 0.1 M adjusted using sodium perchlorate. In all the reactions the ester concentration was 1.84 × 10-4 M and the metal complex was present in at list 10 fold excess. In the concentration range of 2x10-3 to 7x10-3 result give excellent fast order dependence on ester concentration the values of kobs as the function of concentration of the metal complex linear way positive intercept as shown in fig.2. The rate expression for the hydrolysis of 4-nitrophenyl acetate in presence of metal complex can be written as kobs = kO +
Chemical interactions between API and excipients result in a degradation of the API, which can influence the absorption and therapeutic effect. Physical interactions can alter the physicochemical parameters of the components, e.g. the solubility, the dissolution rate and finally the bioavailability. Adsorption of drug molecules onto the surface of excipients can render the drug unavailable for dissolution and diffusion, which can result in reduced bioavailability. For example, antibacterial activity of cetylpyridinium chloride was decreased when magnesium stearate was used as lubricants in tablet containing cetylpyridinium chloride; this was due to adsorption of cetylpyridinium cation by stearate anion on magnesium stearate particle.
For example a simple resolution for the enantiomers of trans-1,2-cyclohexanediol by diastereomeric complex formation with tartaric acid and subsequent supercritical fluid extraction is developed. (7) Solid-phase Extraction (SPE) Principle SPE is a selective extraction technique where the compounds of interest are partitioned between a sorbent phase and a sample liquid in a cartridge, where these compounds must have greater affinity for the sorbent phase than for the sample liquid. The choice of sorbents depends on the interaction of compounds of interest and the chosen sorbent through the functional groups of the compounds. Typically, sorbents used in SPE consists of 40μm diameter silica gel with approximately 60 Aº pore diameters. The steps in SPE is described in
Positive results should be red-purple residue. The principles involved in this test were oxidation of purine by concentrated HNO3; condensation reaction of alloxan to form alloxanthin; and neutralization which forms the red purple murexide or the potassium salt of purpurate. In the sample, the red-purple residue did not appear which means that there is the absence of purines in the DNA
Analytical indices related to fats and oils can be distinguished as structure or quality indices. Structure indices are the iodine value (IV), a measure of total unsaturation of an oil or fat; the saponification value (SV), an indicator of average M.W. ; and the hydroxyl value (HV), which is applicable to fatty compounds (or their mixtures) containing (Knothe, 2002). Saponification is the hydrolysis of fats or oils under basic conditions to afford glycerol and the salt of the corresponding fatty acid (Chalmers and Bathe, 1978). The saponification number is the number of milligrams of potassium hydroxide required to neutralize the fatty acids resulting from the complete hydrolysis of 1g of fat.
Then, toluene is added with continuous stirring before transferring the mixture to a separating funnel. The two immiscible layers formed within few minutes. The transfer of metal salts from the aqueous phase to toluene then completes where ethanol is found to be very important candidate without which metal ions would not be transferred to the organic phase by the direct mixing of an aqueous metal precursor solution with an organic solvent containing dodecyl amine. The fact that water and ethanol are miscible ensures the maximum contact between metal ions and dodecyl amine. A large number of commonly used popular methods, e.g., wet chemistry reduction, seed mediated growth, co-reduction, and solvothermal approaches could be adopted to produce metal or semiconductor nanoparticles after the transfer into the organic solvent.