[Good laboratory practice of equilibrium solubility measurement II. Study of pH-dependent solubility of ionizable compounds].

Acta Pharm Hung

Semmelweis Egyetem, Gyógyszerészi Kémiai Intézet, 1092 Budapest, Hogyes Endre u. 9.

Published: August 2011

In this paper the pH-equilibrium solubility profiles of ionizable drugs are presented. The aim of the present work was to study the validity of the Henderson-Hasselbalch (HH) relationship in the case of structurally diverse weak bases. In the case of monoprotic bases, namely papaverine, promethazine and propafenone the experimental equilibrium solubility data precisely follow the theoretical HH curve until the limit of salt solubility. The common ion effect on salt solubility was found to be significant at low pHs. Deviation from the HH equation in the case of dibasic quetiapine hydrogen fumarate can be easily interpreted with the formation of different salt compositions. The significance of pH control and the effect of the salt form (e.g., fumarate) was also investigated. It is critical that the pKa value and the intrinsic solubility are accurately determined when the HH relationship is used to predict the pH-dependent aqueous solubility of drugs.

Download full-text PDF

Source

Publication Analysis

Top Keywords

solubility
8
equilibrium solubility
8
salt solubility
8
[good laboratory
4
laboratory practice
4
practice equilibrium
4
solubility measurement
4
measurement study
4
study ph-dependent
4
ph-dependent solubility
4

Similar Publications

Mercury sequestration in alkaline salt low-level radioactive waste.

Environ Sci Pollut Res Int

January 2025

Savannah River National Laboratory, Aiken, SC, USA.

Liquid low-level radioactive waste at the Savannah River Site contains several species of mercury, including inorganic, elemental, and methylmercury. This waste is solidified and stabilized in a cementitious waste form referred to as saltstone. Soluble mercury is stabilized as β-cinnabar, HgS as the result of reaction between the mercury and sulfur present in blast furnace slag, one of the cementitious reagents.

View Article and Find Full Text PDF

Pigment particles used in tattooing may exert long terms effect by releasing diffusible degradation products. In the present work, aqueous suspensions of the organic orange diazo pigment PO13 were aged by exposure to simulated sunlight at 40 °C. The morphology and the surface charge of PO13 particles were barely modified upon aging, but primary particles were released by de-agglomeration.

View Article and Find Full Text PDF

Gastrointestinal absorption and its regulation of hawthorn leaves flavonoids.

Sci Rep

January 2025

School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai, 201203, P.R. China.

Hawthorn leave flavonoids (HLF) are widely used as an herb or dietary supplements for cardio-cerebrovascular diseases. However, its gastrointestinal absorption behavior and mechanism have not been disclosed. In this study, gastrointestinal absorption and its regulation of 4''-O-glucosylvitexin (GLV), 2''-O-rhamnosylvitexin (RHV), vitexin (VIT), rutin (RUT) and hyperoside (HP) in HLF were investigated using in vitro, in situ and in vivo models.

View Article and Find Full Text PDF

In this study, the improvement mechanism of yeast proteins (YPs) with the ultrasonic and pH shifting treatment on the emulsion stability was investigated through the solubility, protein structure and interface behavior of YPs. Compared with only pH shifting or ultrasound treatment, the solubility of YPs with the combined treatment of ultrasonic and pH shifting was increased significantly. The soluble protein content of pH-U400 reached 85.

View Article and Find Full Text PDF

Identification of acetylcholinesterase inhibitors and stability analysis of THC@HP-β-CD inclusion complex: A comprehensive computational study.

Talanta

December 2024

Department of Pathology, College of Medicine, King Khalid University, Asir, 61421, Saudi Arabia; Forensic Medicine and Clinical Toxicology Department, Mansoura University, Egypt. Electronic address:

Complexing medications with cyclodextrins can enhance their solubility and stability. In this study, we investigated the host-guest complexation between Tetrahydrocurcumin (THC) and Hydroxypropyl-β-Cyclodextrin (HP-β-CD) using density functional theory (DFT) at the B3LYP-D3/TPZ level of theory in two possible orientations. To determine the reactive sites in both complexes for electrophilic and nucleophilic attacks, we calculated and interpreted the binding energy, HOMO and LUMO orbitals, global chemical reactivity descriptors, natural bond orbital (NBO) analysis, and Fukui indices.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!