Solubility improvement of drugs using N-methyl pyrrolidone.

The solubilization efficiency of N-methyl pyrrolidone (NMP) has been determined and compared to that of ethanol and propylene glycol for 13 poorly soluble drugs. NMP is found to be a more efficient solubilizer for all the drugs studied. The solubility enhancement as high as about 800-fold is obtained in 20% v/v NMP solution as compared to water.

Degradation kinetics and mechanism of RH1, a new anti-tumor agent: a technical note.

The purpose of this research was to study the effect of the lipid matrix on the entrapment of olanzapine (OL). OL-loaded solid lipid nanoparticles (SLNs) were prepared using lipids like glyceryl monostearate (GMS), Precirol ATO 5 (PRE), glyceryl tristearate (GTS), and Witepsol E85 (WE 85)—and poloxamer 407 and hydrogenated soya phosphatidylcholine as stabilizers—using a hot melt emulsification high-pressure homogenization technique, and then characterized by particle size analysis, zeta potential, differential scanning calorimetry (DSC), and powder X-ray diffraction (pXRD). Homogenization at 10 000 psi for 3 cycles resulted in the formation of SLNs with a mean particle size of ∼190 nm for the 4 lipids investigated.

Estimation of the aqueous solubility of weak electrolytes.

Jain and Yalkowsky [Jain, N., Yalkowsky, S.H.

Structure determination and characterization of carbendazim hydrochloride dihydrate.

The objective of this study was to synthesize and characterize the hydrochloride salt of carbendazim with the aim of improving the intrinsic solubility of the parent compound. Carbendazim hydrochloride dihydrate was synthesized for the purpose of increasing the aqueous solubility of the parent drug, carbendazim. This was done with the commonly used saturation and cooling method.

Bilinear model for the prediction of drug solubility in ethanol/water mixtures.

A new bilinear function that accounts for the disparity between the log-linear and parabolic models for cosolvent solubilization is presented, where ethanol was used as the model cosolvent. This accounts for both the initial and terminal slopes in the ethanol/water solubility profiles of semi-polar solutes. The proposed model has only two fitted parameters sigmaA and sigmaB, which represent the initial and terminal asymptotes in the solubility profiles.

Comparison of the octanol/water partition coefficients calculated by ClogP, ACDlogP and KowWin to experimentally determined values.

The experimental octanol/water partition coefficient data, of 108 compounds from the data set [Rytting, E., Lentz, K.A.

Estimation of the ethanol/water solubility profile from the octanol/water partition coefficient.

While the ethanol/water solubility profiles of very polar and very non-polar drugs are monotonic, many semi-polar drugs show a maximum solubility at an ethanol volume fraction (f(max)) between 0 and 1. A sigmoidal relationship was observed between the value of f(max) and the log of the octanol/water partition coefficient (logK(ow)) of the solute. This relationship reasonably predicts the value of the volume fraction of ethanol that gives maximum solubility (f(max)).

Deviation from linearity of drug solubility in ethanol/water mixtures.

A new empirical function that describes the deviation from linearity of solubility of a drug in an ethanol/water matrix is applied to the experimental data for 51 compounds. The proposed model is a more accurate predictor of the co-solvent solubility profile than a general third order polynomial with the same number of parameters. Both the root mean square error and average absolute error for the proposed model are significantly lower than those of existing models.