Comparative study on the rheological properties and tablettability of various APIs and their composites with titanate nanotubes

The present study aimed to investigate the processability of API-titanate nanotube composites into direct compressed tablets and therefore to reveal the benefits of the composite formation provided in tablet manufacturing. Diltiazem hydrochloride, diclofenac sodium, atenolol, hydrochlorothiazide and their 1:1 ratio composites formed with titanate nanotubes (TNTs) were used for the comparative investigations focusing on flowability, compaction behaviour and post-compressional property measurements. The flowability was studied by measuring the flow time, the angle of repose, the Hausner Ratio and the Compressibility Index, while the compaction properties were estimated by the use of out-of-the-die method applying Kawakita and Walker models. The tablet properties were described by determining the apparent tablet density, the breaking strength and the disintegration time. Based on the experimental results, the composites have superior flowability and display better compactibility and compressibility than the pure APIs. These findings were supported by the more favourable post-compressional properties shown by the composite containing tablets. However, the measurements also revealed that the advantageous effect of TNTs on drug tablettability depends on the efficiency of the incorporation process. © 2017 Elsevier B.V

Photocatalytic H2 Evolution Using Different Commercial TiO2 Catalysts Deposited with Finely Size-Tailored Au Nanoparticles: Critical Dependence on Au Particle Size

One weight percent of differently sized Au nanoparticles were deposited on two commercially available TiO2 photocatalysts: Aeroxide P25 and Kronos Vlp7000. The primary objective was to investigate the influence of the noble metal particle size and the deposition method on the photocatalytic activity. The developed synthesis method involves a simple approach for the preparation of finely-tuned Au particles through variation of the concentration of the stabilizing agent. Au was deposited on the TiO2 surface by photo- or chemical reduction, using trisodium citrate as a size-tailoring agent. The Au-TiO2 composites were synthetized by in situ reduction or by mixing the titania suspension with a previously prepared gold sol. The H2 production activities of the samples were studied in aqueous TiO2 suspensions irradiated with near-UV light in the absence of dissolved O2, with oxalic acid or methanol as the sacrificial agent. The H2 evolution rates proved to be strongly dependent on Au particle size: the highest H2 production rate was achieved when the Au particles measured ~6 nm

Az elhízás és cukorbetegség kezelésére alkalmas új molekuláris targetek meghatározása és validálása = Identification and validation of novel molecular target for obesity and type 2 diabetes

A kutatási tervben megfogalmazott programunk elsődleges célja az volt, hogy korunk népbetegségének számító elhízás, metabolikus szindróma és 2-es típusú cukorbetegség kialakulásában szerepet játszó élettani és kórélettani mechanizmusokat feltárjuk, továbbá gyógyszerfejlesztési célpontokat azonosítsunk ezen betegségek megelőzésére és kezelésére. A program másodlagos célja, a cukorbetegek körében nagyon gyakori halálok, a szív és érrendszeri betegségek, elsősorban a szívritmuszavarok kialakulásának hátterében álló mechanizmusok tisztázása volt. Munkánk során különböző állatkísérletes modellekben, patkányokon és nyulakon vizsgáltuk: a CCK szerepét az atípusos antipsychoticumok szedése okozta súlygyarapodásra; a hyperinsulinaemia hatását a cardialis elektrofiziológiai paraméterekre. Új DPP-IV gátló vegyületeket terveztünk és szintetizáltunk, majd meghatároztuk hatásosságuk mértékét. Egy klinikai tanulmányban egészséges önkénteseken vizsgáltuk az egyszeri dózisban adott olanzapinnak (atípusos antipsychoticum), az étkezés kiváltotta CCK felszabadulásra gyakorolt hatását. Intézetünk izotóp laboratóriumában új radioimmunoassay (RIA) eljárásokat fejlesztettünk ki az OTKA támogatás segítségével a GLP-1, GIP, oxyntomodulin, thrittene és a corticosterone mérésére. | The primary objective of our proposed project was to explore the physiological and pharmacological basis of the development of obesity, insulin resistance and type-2 diabetes. The secondary objective of our research program was the investigation of the pathophysiological basis of the cardiac complication of the insulin resistance and diabetes. In this program: the role of CCK in the atypical antipsychotic-induced weight gain; the effect of hyperinsulinaemia on the cardiac electrophysiological parameters were investigated in different animal models using rats and rabbits. New chemical entities having DPP-IV blocking activity were designed and synthetized and their potencies were determined. In a clinical trial we investigated the possible role of a single dose of olanzapine, an atypical antipsychotic, on the meal-induced CCK release in healthy volunteers. Furthermore, new radioimmunoassay (RIA) methods were developed in our institute for the measurement of GLP-1, GIP, oxyntomodulin, thrittene and corticosterone with the support of OTKA