Retention and Separation Changes of Ternary and Quaternary Alkaloids from Chelidonium majus L. by TLC Under the Influence of External Magnetic Field.

Thin layer techniques proved their usefulness in the analysis of plant extract material. Thanks to their low operation costs, high sample throughput and possibility to gather chromatographic data for the whole sample in a single act, they allowed to find, and in some cases identify, active ingredients often hidden in sophisticated plant extract matrices. It was also proved that the presence of a magnetic field changes the retention of some substances, and moreover changes the separation efficiency of chromatographic systems. In the presented experiment, retention, efficiency and separation abilities of TLC chromatographic systems for mixtures of alkaloids under the influence of magnetic field depending on inductivity of the magnetic field, the saturation of chromatographic chamber and quantity of chromatographed substances were investigated. The results obtained were tested on real plant extracts that revealed the ability of chromatography in a magnetic field for separation of ternary and quaternary alkaloids from Chelidonium majus L. Our experiments proved that the presence of magnetic field induction lines perpendicular to the chromatographic plate plane can influence the width and retention of chromatographed substances, and can be considered as a tool for separation adjustment of plant extracts containing ternary and quaternary alkaloids.

Determination of binding properties of ampicillin in drug-human serum albumin standard solution using N-vinylpyrrolidone copolymer combined with the micellar systems.

It is well-known that only the unbound (free) drug fraction can achieve a pharmacological effect. Therefore the determination of free drug concentration is a very important issue in the field of pharmacology. In this study poly-1-vinyl-2-pyrrolidone (VP) crosslinked with divinylbenzene (DVB) compared with the micellar liquid chromatography (MLC) with and without pre-made drug adsorption was used for quantitative analysis of free ampicillin concentration in the standard solution of drug-human serum albumin owing to its ability to block protein adsorption. The commonly recognized adsorption method based on drug adsorption on VP-DVB has been compared to the entirely new application of MLC with direct sample injection (DSI) not requiring pre-made adsorption. Micellar aggregates are able to solubilize various compounds therefore micellar environment can be used for direct determination of free drug concentration. The obtained results show that the free drug concentration values obtained in the micellar systems based on cetyltrimethylammonium bromide (CTAB) (93.98µgL-1, 78.3%) as well as on polyoxyethylene (23) lauryl ether (Brij35) (91.15µgL-1, 75.9%) are similar to those obtained after the drug adsorption on VP-DVB using both RP-HPLC (95.85µgmL-1, 79.9%) and spectrophotometry (96.47µgmL-1, 80.4%). However, only %PPB (% plasma protein binding) value calculated on the basis of Brij35 retention factor is similar to the literature data. The obtained results are within the analytical range of % of free drug concentration. Therefore N-vinylpyrrolidone copolymer as well as micellar system based on the non-ionic surfactant can be successfully applied for determination of free drug concentration. Moreover, the new application of MLC with DSI can be recognized as a promising, fast and simple method for quantitative determination of free drug concentration.

HPTLC and magnetochromatography of new complexes of carboxylates with transition metals or rare earth elements and their ligands - study of lipophilicity.

Nineteen new complexes of carboxylates with transition and rare elements as central ions and their ligands were characterized by chromatographic analyses. The parameter of relative lipophilicity (RM0 ) of the tested compounds was determined experimentally by the reversed-phase high-performance thin layer chromatography method with mixtures of various organic modifiers (acetonitrile, acetone, dioxane) and water as a mobile phase. The extrapolated RM0 values were compared with the logP values calculated from the molecular structures of tested solutes. Similarities between the lipophilicity indices were analysed by principal component analysis and linear regression. Thin-layer chromatography combined with a magnetic field has been proposed as a complementary method for determination of lipophilicity of the investigated compounds. The chromatograms in the field and outside it were developed simultaneously in two identical chromatographic chambers. One of them was placed in the external magnetic field of 0.4 T inductivity. We proved that chelation causes a drastic change in compound lipophilicity, but all complexes did not exhibit enhanced activity as compared with the parent ligand. Also in the magnetic field the retention of some complexes changed, which means that the presence of the field influences the physicochemical properties of the compounds and their interactions with the stationary phase.

Skin-mimetic chromatography for prediction of human percutaneous absorption of biologically active compounds occurring in medicinal plant extracts.

The main aim of this study was to predict quantitatively human percutaneous absorption of chosen compounds commonly occurring in plants which can be used as medicinal extracts in the drug and beauty industries. The most important human percutaneous descriptors, i.e. logKp (logarithm of the water/skin partition coefficient) and logJmax (logarithm of the maximum flux of solutes penetrating the skin), of fatty acids and polyphenols were determined using both in vitro and in silico methods. For in vitro determination of human percutaneous absorption, micellar liquid chromatography based on hexadecyltrimethylammonium bromide, sodium dodecyl sulfate and polyoxyethylene (23) lauryl ether (Brij35) was used. Human percutaneous absorption was characterized by entirely new QSAR/QRAR models based on retention, lipophilic, steric and electronic data as well as on the linear free energy relationship parameters. Many different correlations between human skin absorption and different physicochemical parameters were performed, e.g. the in silico estimated logKp value was correlated with the retention parameter logkw (logarithm of the retention factor extrapolated to pure water) from the systems imitating a cutaneous environment (R2 = 0.92). Moreover, the influence of lipophilicity on percutaneous absorption was examined. The obtained correlation was excellent (R2 = 0.95).

A new application of micellar liquid chromatography in the determination of free ampicillin concentration in the drug-human serum albumin standard solution in comparison with the adsorption method.

The determination of free drug concentration is a very important issue in the field of pharmacology because only the unbound drug fraction can achieve a pharmacological effect. Due to the ability to solubilize many different compounds in micellar aggregates, micellar liquid chromatography (MLC) can be used for direct determination of free drug concentration. Proteins are not retained on the stationary phase probably due to the formation of protein - surfactant complexes which are excluded from the pores of stationary phase. The micellar method is simple and fast. It does not require any pre-preparation of the tested samples for analysis. The main aim of this paper is to demonstrate a completely new applicability of the analytical use of MLC concerning the determination of free drug concentration in the standard solution of human serum albumin. The well-known adsorption method using RP-HPLC and the spectrophotometric technique was applied as the reference method. The results show that the free drug concentration value obtained in the MLC system (based on the RP-8 stationary phase and CTAB) is similar to that obtained by the adsorption method: both RP-HPLC (95.83µgmL(-1), 79.86% of free form) and spectrophotometry (95.71µgmL(-1), 79.76%). In the MLC the free drug concentration was 93.98µgmL(-1) (78.3%). This indicates that the obtained results are within the analytical range of % of free ampicillin fraction and the MLC with direct sample injection can be treated like a promising method for the determination of free drug concentration.

in vitro and in silico determination of oral, jejunum and Caco-2 human absorption of fatty acids and polyphenols. Micellar liquid chromatography.

In this investigation chosen saturated, mono- and polyunsaturated fatty acids as well as polyphenols have been analyzed. The main aim of this study was to determine oral, jejunum and Caco-2 human absorption of chosen fatty acids and polyphenols using in vitro and in silico methods. For in vitro determination of human drug absorption, the usefulness of Micellar Liquid Chromatography (MLC) with mobile phases containing different surfactants (including Brij35-Biopartitioning Micellar Chromatography (BMC)) has been confirmed. On the basis of Foley's equation, 1/k vs. CM correlations for the tested compounds have been done. Satisfactory linearity of the relationships was found over the whole eluents composition range studied with R(2) approximately 0.99 in each case. Moreover, the analyte-micelle association constants (Kma) from Foley's equation have been compared for different micellar environments, containing Brij35, SDS and CTAB as a main component of micellar mobile phases. Completely new models describing human oral as well as Caco-2 and jejunum absorption have been constructed and compared with the cited models. These models are based on the Abraham descriptors and lipophilicity parameters as well as steric descriptors. Furthermore, many different correlations between physicochemical parameters and human intestinal absorption have been done, e.g. the correlation between human jejunum permeability estimated in silico and received using LSER parameters was excellent (R(2) nearly 0.99). Chromatographic parameters have been collated with steric, electronic and physicochemical ones using QRAR (Quantitative Retention - Activity Relationships) and QSAR (Quantitative Structure - Activity Relationships) models. Moreover, retention BMC data have been compared with lipophilicity parameter logPo/w (n-octanol-water partition coefficient). The influence of lipophilicity on oral absorption (%) has been checked. The correlation between predicted oral absorption (%) and logPo/w has been done. Obtained R(2) was 0.82. On the basis of chromatographic, lipophilicity, steric and different physicochemical parameters, the principal components analysis (PCA) has been done.

Chromatographic Study of Novel Heteronuclear Complexes with Schiff Base as Main Ligand.

The properties of 12 new heterodi- and heterotrinuclear complexes having general formulae [Cu2Ln(L)2(NO3)(H2O)2](NO3)2·3H2O [where Ln = Pr (1), Nd (2), Sm (3) and Eu (4)], and [CuLn(L)(NO3)2(H2O)3MeOH]NO3·MeOH [where Ln = Gd (5), Tb (6), Dy (7), Ho (8), Ef (9), Tm (10), Yb (11) and Lu (12)], and their main ligand [L = C19H18N2O4Br2 = N,N'-bis(5-bromo-3-methoxysalicylidene)propylene-1,3-diamine] have been characterized by chromatographic analyses. The parameter of relative lipophilicity (RM0) of the tested compounds was determined experimentally by reversed-phase high-performance thin layer chromatography method with mixtures of methanol and water as a mobile phase. We also described interactions between chromatographed substances and various surfaces (silica-SiO2 and modified by hydrocarbon chains-RP-2, RP-8, RP-18 phases). This study also investigates the effect of pH of the mobile phase on the retention on the polar stationary phase. Thin layer chromatography combined with magnetic and electric field has been proposed as a complementary method for the determination of physicochemical properties of the investigated compounds. The chromatograms in the field and outside of it were developed simultaneously in three identical chromatographic chambers. One of them was placed in external magnetic field of 0.4 T inductivity, and the second in external electrical field. In magnetic and electric fields, retention of some complexes changed, which indicated that the presence of these fields influenced physicochemical properties of the compounds and their interactions with the stationary phase.

Comparison of TLC and Different Micro TLC Techniques in Analysis of Tropane Alkaloids and Their Derivatives Mixture from Datura Inoxia Mill. Extract.

Planar chromatography is a very useful tool for analysis of wide range of different mixtures. Thanks to its possibility for rapid separation of large number of samples simultaneously, low solvent consumption and ability to analyse rough material allow to receive precise and reliable results in short time and low cost. Miniaturization of planar techniques brings a lot of advantages, such as shortening distance and time of chromatogram development, and further lowering of solvent consumption. Besides, it often allows to improve separation parameters and raise efficiency of chromatographic system. In this paper, ability of analysis of tropane alkaloids mixture from Datura Inoxia Mill. extract using conventional TLC technique with five micro TLC techniques (short distance TLC, HPTLC, UTLC, OPLC and ETLC) in maximally closed chromatographic conditions was compared in order to present abilities of micro TLC techniques in plant material analysis.

The use of biopartitioning micellar chromatography and immobilized artificial membrane column for in silico and in vitro determination of blood-brain barrier penetration of phenols.

Biopartitioning Micellar Chromatography (BMC) is a mode of micellar liquid chromatography that uses C18 stationary phases and micellar mobile phases of Brij35 under adequate experimental conditions and can be useful to mimic human drug absorption, blood-brain barrier distribution or partitioning processes in biological systems. BMC system can be useful in constructing good predictive models because the characteristics of the BMC system are similar to biological barriers and extracellular fluids. Immobilized Artificial Membrane (IAM) chromatography uses stationary phase which consists of a monolayer of phosphatidylcholine covalently immobilized on an inert silica support. IAM columns are thought to mimic very closely a membrane bilayer and are used in a HPLC system with a physiological buffer as eluent. In this paper the usefulness of BMC and IAM system for in silico and in vitro determination of blood-brain barrier (BBB) penetration of phenols has been demonstrated. The most important pharmacokinetic parameters of brain have been obtained for the determination of BBB penetration, i.e. BBB permeability - surface area product (PS), usually given as a logPS, brain/plasma equilibration rate (log(PS×fu,brain)) and fraction unbound in plasma (Fu). Moreover, the relationships between retention of eighteen phenols and different parameters of molecular size, lipophilicity and BBB penetration were studied. Extrapolated to pure water values of the logarithms of retention factors (logkw) have been compared with the corresponding octanol-water partition coefficient (logPo-w) values of the solutes. In addition, different physicochemical parameters from Foley's equation for BMC system have been collated with the chromatographic data. The Linear Solvation Energy Relationship (LSER) using Abraham model for the describing of phenols penetration across BBB has been used. Four equations were developed as a multiple linear regression using retention data from IAM and BMC system (QRAR models) and molecular volume parameter (Vm) and Abraham descriptors to correlate the logBB values. Moreover, in order to establish the relationships between different variables, the principal components analysis (PCA) has been done. The results of PCA were obtained using chromatographic data from IAM and BMC systems as well as from the structures of tested phenols. The four parameters: logkwIAM(exp), logkwBMC(exp), analyte-micelle association constant (Kma) and logPo-w have been checked.

Some aspects of TLC in homogenous magnetic fields.

This article consists of two parts. First part is a short review about the role of magnetic phenomena in natural environment, human surroundings, and his activities such as science, engineering, and medicine. The second part of the article presents a set of experiments, their results, and data obtained in a static homogenous magnetic field, generated by a pair of permanent magnets and outside it. Adsorption chromatographic systems were investigated: as chromatographed substances - polyaromatic hydrocarbon (PAH), as stationary phase - silica gel 60, as monocomponent mobile phases - n-hexane, n-heptane, n-octane, and benzene were used and binary mobile phases n-hydrocarbons - benzene. Magnetic field influences retention and efficiency of investigated chromatographic systems. Experimental data analysis (RF, N) allows us to propose some explanations of the differences between experiment results performed in induced magnetic field and outside it, and in consequence on the changes in the interfacial phenomena induced by field presence.

[Successes and failures of ozena's medical treatment]. / Sukcesy i porazki zachowawczego leczenia ozeny.

Ozena belongs to the primary atrophic rhinitis of unknow etiology. The incidence of this disease has markedly decrease in the last decades. We treated 4 patients with ozena between 2000-2005. The diagnosis was confirmed by physical and ENT examination, culture from the nose and CT scan of perinasal sinusis. Ciprofloxacin was aministrated orally in a dose 1,0-0,5 g daily to all patients. Also they were instructed how to clean the nose regularly with an isotonic saline solution and to moisteurse nosa by wotery spray. The treatment with ciprofloxacin was maintained for 4-6 weeks. In 3 causes the result was very good after 2-4 y observation. 1 patient, 16 y. old girl, didn't cooperate therapy propely - she stoped nasal rinsing after some improvement. The second course of treatment seems to get good result (3 months observation). Our and some other authors conclusion is: ciprofloxacin seems to be a promising drug for the treatment of ozena. For good results cleanising the nose regularly is importent as well as antibiotic.

[Long-term results of transtympanic gentamicin treatment in Meniere's disease]. / Odlegle wyniki transtympanalnego leczenia gentamycyna w chorobie Meniere'a.

OBJECTIVE: To determine the long-term hearing and vestibular outcomes in patients with intractable vertigo caused by unilateral Meniere's disease, who were treated with transtympanic injection of gentamicin. STUDY DESIGN: the study was a long-term analysis of hearing and control of vertigo in patients with unilateral Meniere's disease who received transtympanic gentamicin. METHODS: Pure-tone thresholds and ENG, along with the control of vertigo. Criteria described in 1995 by the American Academy of Otolaryngology - Head and Neck Surgery were used. Patients treated with transtympanic gentamicin had definite Meniere's disease and had intractable vertigo despite optimal medical therapy, no symptoms suggestive of Meniere's disease in the contralateral ear, and serviceable hearing in the contralateral ear. The study analyzed the outcomes of 9 patients for whom follow-up data were available for periods greater than 24 months after transtympanic gentamicin. RESULTS: Complete control of vertigo was obtained in all 9 patients. Profound sensorineural hearing loss occurred only in 1 patient. Hearing was improved in 6 patients, and in 2 was unchanged. CONCLUSIONS: Transtympanic gentamicin therapy is a good method of controlling vertigo and the risk of hearing loss is low.

[Transtympanic steroid application in sudden deafness]. / Transtympanalne podawanie steroidów w leczeniu naglej gluchoty.

The paper presents the results of transtympanic steroid therapy for sadden sensorineural hearing loss in 20 patients. All patients previously underwent a full conventional treatment, without the beneficial effect. Patients were classified into two groups: the first one consisted of 16 patients who received intratympanic Dexaven application just after termination of conventional treatment. The second group received intratympanic treatment 1 or more months after the conventional therapy had been finished. The pattern of intratympanic Dexaven application is presented. The results of treatment are promising (hearing improvement in 7 cases) and the method is both minimally invasive and inexpensive.

[Labyrinthectomy with preservation of the cochlear duct and a reconstruction of the lateral wall in the vestibule]. / Labiryntektomia z zachowaniem przewodu slimaka i rekonstrukcja bocznej sciany przedsionka--zastosowanie kliniczne.

The authors described a technique and presented the results of the modified labyrinthectomy in 9 cases. A labyrinthectomy was performed during the removal of neuromas by translabirynthine approach, in advanced unilateral Meniere disease, in a huge perylimphatic fistula and in a case of labyrinthitis latens. In 3 cases of the neuromas removal the residual hearing was preserved. In remained cases of labyrinthectomy hearing was preserved partially.

[The role of immunological factors in Meniere's disease]. / Rola czynników immunologicznych w chorobie Meniere'a.

Involvement of the immunological mechanisms in the pathogenesis of Meniere's disease has been discussed over the past two decades. Nevertheless, we lack well-defined laboratory tests that might confirm the autoimmune background of the disorder. Therefore the diagnosis is often based solely on the patient's clinical profile and the positive response to the immunosuppressive therapy. In this article we present a case of 44 year-old woman with Meniere's disease successfully treated with systemic glucocorticoids. The pathogenesis, diagnosis and management of immune-mediated cases of Meniere's disease are reviewed.