Scientia Pharmaceutica

2920 KiB

Open AccessArticle

Analysis of the sesquiterpenes in Achillea species usinq liquid chromatography-mass spectrometry with positive ion atmospheric pressure chemical ionisation

by Katharina Rothwangl-Wiltschnigg, Sabine Glasl, Ingrid Werner and Gottfried Reznicek

Sci. Pharm. 2004, 72(3), 249-258; https://doi.org/10.3797/scipharm.aut-04-21 - 11 Sep 2004

Cited by 1 | Viewed by 1335

Abstract

The species of the Achillea millefolium group contain different sesquiterpenes which are of chemotaxonomical and pharmacological interest. Therefore the HPLC analysis of these compounds is a fundamental task for the quality control of Achillea samples. As difficulties in identification solely on the basis of retention times may arise, the LC was coupled with atmospheric pressure chemical ionisation mass spectrometry (APCI-MS) allowing a selective and sensitive detection and thus the clear identification of the sesquiterpenes. Full article

3289 KiB

Open AccessArticle

Differential Pulse Voltammetric Determination of Loperamide in a Pharmaceutical Dosaqe Form

by A. Radi and T. Elmogy

Sci. Pharm. 2004, 72(3), 239-248; https://doi.org/10.3797/scipharm.aut-04-20 - 9 Sep 2004

Cited by 4 | Viewed by 1402

Abstract

A voltammetric study of the oxidation of loperamide has been carried out at the glassy carbon electrode. This compound exhibited a single peak in Britton-Robinson buffer solutions of pH 5.0–11.0, with a maximum current at pH 8.0. The electrochemical oxidation of loperamide is identified as an irreversible, diffusion-controlled process. Based on this study, a simple, rapid and sensitive voltammetric method was applied, without any interference from the excipients, to the determination of the drug in a capsule dosage form. Full article

3093 KiB

Open AccessArticle

Comparative Bioavailabilitv Studv of Two Brands of Terbutaline Sulphate Tablets in Healthy Human Volunteers

by Nahla S. Barakat, Nawal M. Khalafallah and Said A. Khalil

Sci. Pharm. 2004, 72(3), 227-237; https://doi.org/10.3797/scipharm.aut-04-19 - 7 Sep 2004

Viewed by 1300

Abstract

The purpose of this study was to evaluate the bioavailability of locally produced 2.5 mg terbutaline sulphate tablets (brand A ) relative to a reference product, Bricanyl 2.5 mg tablets (brand 6). The study was a single dose 5 mg randomized crossover one in 15 healthy volunteers in the fasting state. Urine was collected at intervals of 24 h. Total terbutaline excreted in urine as unchanged drug and as conjugates (sulphate and glucuronide) was determined by a developed and validated HPLC method. In-vitro characteristics of both brands were similar. Based on percent of the dose excreted in urine, the oral bioavailability ranged from 33.5% to 75.8% for both brands. Statistics were applied to judge bioequivalence according to USP 24 in-vivo bioequivalence guidance. Results indicated that brand A and B were bioequivalent and hence interchangeable in medical practice. Full article

2506 KiB

Open AccessArticle

A VALIDATED HPLC-ASSAY FOR THE DETERMINATION OF MELOXICAM IN PRESENCE OF ITS DEGRADATION PRODUCTS

by Herbert Bartsch, Angelika Eiper, Hannelore Kopelent-Frank and Jiři Procházka

Sci. Pharm. 2004, 72(3), 213-220; https://doi.org/10.3797/scipharm.aut-04-17 - 3 Sep 2004

Viewed by 1321

Abstract

The stability of aqueous solutions of meloxicam is studied with samples of different concentrations, and in different containers. Quantitation is carried out utilizing a validated stability indicating HPLC assay with five-point calibration. Sample solutions of meloxicam of three different concentrations (2 mg ml⁻¹; 250 µg ml⁻¹; 40 µg ml⁻¹) are subjected to simulated sunlight and tested for stability. A distinct correlation of the photodegradation rate with the concentration of the sample solution was found. Furthermore, the influence of size and geometry of the containers in which the solutions were exposed to light was investigated and results compared. Full article

4598 KiB

Open AccessArticle

N-(3,4-Dichlorobenzyl)azoles—Investigations Regarding Synthesis, NMR-Spectroscopy and Affinity Towards Sisma-1 and Sigma-2 Receptors

by Wolfgang Holzer, Bettina Brandstätter, Christine Jäger, Michael Kaun, Thierry Langer and Wayne D. Bowen

Sci. Pharm. 2004, 72(3), 197-211; https://doi.org/10.3797/scipharm.aut-04-16 - 1 Sep 2004

Viewed by 1332

Abstract

A series of azoles and aminoazoles with a 3,4-dichlorobenzyl moiety attached to a ring nitrogen atom was synthesized via reaction of the parent systems with 3,4-dichlorobenzyl chloride. Regioisomeric products were discriminated on the basis of ¹³C-NMR data or by NOE-difference spectroscopy. The [...] Read more.

1414 KiB

Open AccessArticle

Study of local anesthetics. Part* 166:Conductometric determination of the critical micelle concentration of local anesthetic heptacainium chloride in aqueous electrolvte solution

by F. Andriamainty, J. Čižmárik and M. Holíková

Sci. Pharm. 2004, 72(3), 221-225; https://doi.org/10.3797/scipharm.aut-04-18 - 11 Aug 2004

Cited by 7 | Viewed by 1099

Abstract

Specific conductivities of local anesthetic heptacainium chloride XlX (HCC XlX) (N-[2-(2-heptyloxyphenylcarbamoyloxy)-ethyl]-piperidinium chloride), in aqueous electrolyte solution (0.05 mol.1⁻¹ NaCl) were measured as a function of the concentration and temperature. The critical micelle concentrations (c.m.c) and the counterion (β) binding of the micelles were estimated from the dependence of the specific conductivity of the substrate concentration. The temperature dependence of ln c.m.c was fitted to the function of the second degree polynomial. From the fitting parameters, Gibss free energies (ΔG⁰), enthalpies (ΔH⁰), and entropies (ΔS⁰) of micellization as a function of temperature were estimated. The "mass action model" was applied to micelle formation to calculate the micellization parameters. Full article

Journal Menu

Journal Browser

Sci. Pharm., Volume 72, Issue 3 (September 2004) – 6 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI