Physico-chemical characterization of some beta blockers and anti-diabetic drugs - potentiometric and spectrophotometric pKa determination in different co-solvents

Narasimham, Lakshmi; Barhate, V. D.

doi:10.5155/eurjchem.2.1.36-46.371

Cited by 24 publications

(8 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This trend of GLZ solubility was consistent with previously published reports (28) and can be explained as GLZ is both an acid due to its sulfonamide proton with pK a of 5.8 (28,29) and a base due to the alicyclic aliphatic amino group with pK a of 2.9 (28). Thus, within the studied pH values, the drug is expected to be in its minimum ionization state at pH 4.5.…”

Section: Solubility and Partition Coefficientsupporting

confidence: 80%

Improvement of Dissolution Rate of Gliclazide Through Sodium Salt Formation

El-Sabawi¹,

Hamdan²

2014

Dissolution Technol.

View full text Add to dashboard Cite

Gliclazide is a hypoglycemic agent exhibiting to some extent inadequate and variable absorption as a consequence of poor aqueous solubility and slow dissolution rates. A sodium salt of gliclazide was prepared and investigated for solubility and dissolution properties in comparison to untreated gliclazide. The salt was formed by adding equimolar amounts of gliclazide and sodium hydroxide in an aqueous-ethanolic phase. To confirm salt formation, sodium gliclazide was fully characterized by spectroscopy, differential scanning calorimetry, and potentiometric titration. Furthermore, solubility and in vitro dissolution studies of formulated tablets were performed at pH values of 1.2, 4.5, and 6.8. Sodium gliclazide demonstrated a significant increase in solubility at pH values of 4.5 and 6.8. The most apparent increase was achieved in unbuffered distilled water with a 235-fold higher solubility. Moreover, sodium gliclazide showed an enhancement in the dissolution rate in all tested media, but most significantly at pH 4.5 and 6.8. The highest difference (60%) in dissolution rate between gliclazide and its sodium salt was obtained at pH 6.8 at 30 min.The sodium salt of gliclazide presents improved solubility and drug dissolution, therefore limiting the possibility of variable absorption and improving the onset of action with potential enhancement in its overall bioavailability.

show abstract

Section: Solubility and Partition Coefficientsupporting

confidence: 80%

Improvement of Dissolution Rate of Gliclazide Through Sodium Salt Formation

El-Sabawi¹,

Hamdan²

2014

Dissolution Technol.

View full text Add to dashboard Cite

show abstract

“…They have been synthesized from a variety of basic compounds, such as aromatic aldehydes (2-naphthaldehyde, pyridine-2-carbaldehyde, etc. ), 2-hydroxy-1-naphthaldehydes, b-diketones, dihydroxy-6-formyl-2-methylbenzopyran-4-one, amino-1,2,4-triazole, ethylenediamine and dipropylene triamine [15][16][17][18][19]. Among these Schiff bases, those derived from salicylaldehyde and other aromatic aldehydes are the most exploited owing to their basicity, chelating ability and stability.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Characterization of a Novel Series of Amphiphilic Mercapto‐1,2,4‐Triazole Schiff Base Ligands: Investigation of their Behavior in Hydro‐Organic Solutions

Boceiri

Benabdallah

Youcef

et al. 2016

J Surfact & Detergents

View full text Add to dashboard Cite

A novel series of four Schiff base amphiphiles derived from 3-mercapto-1,2,4-triazole and different alkyl chains were successfully prepared by a new synthetic three-step method. The chemical structures of the different ligands were characterized by elemental analysis, FT-IR spectroscopy, 1 H-NMR and 13 C-NMR spectra. The effect of the chain length on the solution behavior of the amphiphilic ligands were studied, in both homogeneous and heterogeneous systems, using pH-metric and spectrophotometric methods. Based on the electronic spectroscopy data, some parameters governing their surfactant properties, such as the critical micelle concentration (CMC), the micellization free energy (DG mic ) and the hydrophilic-lipophilic balance (HLB) were evaluated in chloroform and discussed. The behavior of the four Schiff bases in the heterogeneous chloroform-water mixture was then explored through the establishment of their acidity (pK A ) and distribution (Log K d ) constants in 1 M chloride medium and the acidity constants in aqueous medium (pK a ) were deduced. Results showed that an increase of the alkyl chain decreases the distribution of the ligands and increases their acidity. The extractive performance of the Schiff base amphiphiles were investigated towards Ni(II) from a chloride medium at 30°C. The analysis of extraction data revealed that the synthesized Schiff bases exhibit a better and faster extractability than many ligands reported in the literature.

show abstract

“…[1,2]. In other words, the predominance of one of the two forms will condition their distribution in the environment, their biological activity or chemical reactivity, among others.…”

Section: Introductionmentioning

confidence: 99%

New chemometric strategies in the spectrophotometric determination of pKa

et al. 2014

View full text Add to dashboard Cite

KEYWORDSIn this work, principal component regression and partial least squares regression were used for the estimation of acid dissociation constants through UV-Vis spectrophotometric measurements, considering five well-known acid-base indicators as well as two herbicides as analytes. In each case, an acid-base titration was carried out. Then, the multivariate calibration model was constructed with a few absorption spectra of the series at extreme pH values, to which values of the dissociation fraction (α) of 1 or 0 were assigned, in the case of HA or A species. After that, the prediction step consisted in the estimation of α for the rest of the series. Then, distribution diagrams were built up with α vs pH, to find α = 0.5 where pH = pKa. The results were compared with those obtained through multivariate curve resolutionalternating least squares and program stability quotients from absorbance data (SQUAD), which showed an excellent correspondence. pKa PLS PCR MCR-ALS Spectrophotometry Chemometric strategies

show abstract

Physico-chemical characterization of some beta blockers and anti-diabetic drugs - potentiometric and spectrophotometric pKa determination in different co-solvents

Abstract: Physico-chemical characterization of some beta blockers and anti-diabetic drugs-potentiometric and spectrophotometric pKa determination in different co-solvents

Cited by 24 publications

References 29 publications

Improvement of Dissolution Rate of Gliclazide Through Sodium Salt Formation

Improvement of Dissolution Rate of Gliclazide Through Sodium Salt Formation

Synthesis and Characterization of a Novel Series of Amphiphilic Mercapto‐1,2,4‐Triazole Schiff Base Ligands: Investigation of their Behavior in Hydro‐Organic Solutions

New chemometric strategies in the spectrophotometric determination of pKa

Contact Info

Product

Resources

About