Use of the pKa Table Discussion: The propensity of a compound to donate a proton is measured as its acid ionization constantor Ka. These Ka values cover a wide range of for the strongest acids such as sulfuric acid to for the weakest acids such as methane. Thus a Ka of becomes a pKa ofand a Ka of becomes a pKa of
Tommy Julianto1 and A. In this study, a reversed-phase high performance liquid chromatography RP-HPLC method has been developed for the quantification of ibuprofen in rat plasma. The mobile phase consisted of a mixture of acetonitrile and water that was adjusted to pH 2.
The flow rate was set at 0. The proposed method was validated based on linearity, accuracy and precision. The linearity of ibuprofen was in the range of 0.
The percentage mean recovery was found to be at The method was further engaged to identify the pharmacokinetic profiles of ibuprofen nanoemulsion and ibuprofen oil solution after oral administration with AUC value of It is widely used in the treatment of rheumatoid arthritis, osteoarthritis and joint pain 1, Ibuprofen is available as a white crystalline powder with a molecular weight of Ibuprofen inhibits prostaglandin biosynthesis by blocking the enzyme cyclooxygenase, which converts arachidonic acid to prostaglandin Ibuprofen is practically insoluble in water and has shown incomplete absorption in the GI tract 3, Thus, ibuprofen has been formulated into inert lipid vehicles such as microemulsions, nanoemulsions, self-emulsifying formulations and liposomes in order to increase the bioavailability of this poorly soluble drug 4.
Based on previous studies conducted on various approaches in analysing ibuprofen, high performance liquid chromatography HPLC was found to be the most suitable method to determine the concentration of the drug in different types of samples. Recent studies stated that HPLC with UV-Vis detector at a wavelength of nm has successfully determined the concentrations of ibuprofen in nanoemulsion formulations with a retention time of 7.
Meanwhile, another study has developed a method for the analysis of ibuprofen and paracetamol using reversed phase HPLC with UV detector at a wavelength of nm with a retention time of 6.
The high sensitivity, accuracy, precision, linearity and stability of HPLC method in the analysis of ibuprofen have made it a widely used method for the determination of ibuprofen concentrations in nanoemulsion formulations.
Nanoemulsion is a heterogeneous system which comprised of oil, surfactant, cosurfactant and an aqueous phase 5, Developing nanoemulsions as vehicles for carrying active pharmaceutical ingredients is emerging as a promising approach to deliver drug to the targeted site of action 6.
Nanoemulsion with an approximate droplet diameter of about nm has the potential to increase the aqueous solubility of poorly water-soluble drugs 5, They are kinetically stable without any flocculation or coalescence after long-term storage because of the nanometer-sized droplets 9, Several advantages of nanoemulsions include smaller droplet size with a larger surface area, increasing dissolution rate and solubility and enhancing mucosal permeability 7, In nanoemulsions, the oil droplets act as a reservoir for hydrophobic drugs 8, The most widely used oil molecules are saturated and unsaturated fatty acids, fatty acid esters, soybean oils as well as olive oils 8, This study was conducted with the purpose of developing a simple reversed-phase high performance liquid chromatography RP-HPLC equipped with a photodiode array detector in order to determine the concentration of ibuprofen in rat plasma.
Oral administration was also carried out in this study to identify and compare the pharmacokinetic profiles of ibuprofen nanoemulsion and ibuprofen oil solution respectively. Olive oil, glycerol, propyl paraben and methyl paraben were supplied by Zulat Pharmacy Malaysia. All other chemicals and solvents were of analytical grade.
Working solutions of ibuprofen with concentrations in the range of 0.As the pka value of aceclofenac is 4. and chlorzoxazon.4 %.1 Precision (Reproducibility) The precision of the method was studied by determining the concentrations of each ingredient in the tablets for six times.7– and chlorzoxazone are observed to be and Prior art keywords paracetamol method according solution aqueous solvent temperature Prior art date Legal status (The legal status is an assumption and is not a legal conclusion.
For example, if asked to determine the pH at the equivalence point in a titration of cm3 of mol dm-3 CH3COOH with mol dm-3 NaOH, students will find the pKa of ethanoic acid () from Table 19 and then work with this value for the rest of their calculation. I'll discuss how to determine pH given "pKa" for a monoprotic acid, which is an acid that only donates one proton per molecule when placed in aqueous solution.
How do you determine pH from pKa? Chemistry Acids and Bases pH. 1 Answer Stefan V. Feb 1, The value of the acid dissociation constant can be derived from #"pKa"# #K_a = for making a Standard Curve), determine the concentration of salicylic acid (SA) for each absorbance reading.
Remember, the equation of the line is of the form y=mx+b, where concentration is the “y” value, the absorbance is the “x value”, and m and b are the slope and intercept of the line. Record the concentration in Table 2. 2. The thermodynamic dissociation constants of losartan, paracetamol, phenylephrine and quinine by the regression analysis of spectrophotometric data.