Hormon salımı için polimerik membran sistemleri

Bu tezde, insülin hormonunun kontrollü salımı için poli(HEMA-GMA) polimerik hidrojel membranlar serbest radikal fotopolimerizasyon yöntemi ile sentezlendi. Monomer ve çağraz bağlayıcı oranları optimize edildi. Polimerik hidrojel membranların oluşumunda en iyi HEMA/GMA mol oranı 3,41 ve en iyi çapraz bağlayıcı oranı % 0,5 (toplam reaksiyon hacminin) olarak belirlendi. Polimerik hidrojel membranların karakterizasyonunda SEM, FTIR, ve şişme testleri yapıldı. En yüksek şişme değeri % 195 olarak tespit edildi. Polimerik hidrojel membranlara farklı oranlarda yüklenen insülinin salım koşullarının optimizasyonu yapıldı. İnsülin salımı en yüksek, 37°C sıcaklıkta yüklenen insülinin kümülatif salım değerleri % 90, pH 4,9 'da yüklenen insülinin kümülatif salım değerleri % 94 ve 0,5 mg/mL insülin yüklü polimerik hidrojel membranlarda yüklenen insülinin kümülatif salım değeri %52 olduğu belirlendi. Polimerik hidrojel membranların şişme kinetiğinin matematiksel analizinde, polimerik hidrojel membranların HEMA/GMA mol oranı azaldıkça difüzyon modeli Fick yasasına uymayan difüzyon modelinden, Fick difüzyon modeline dönüştüğü belirlendi. Ayrıca, söz konusu polimerik hidrojel membranlar için difüzyon katsayıları 3,66x10-3 , 9,01x10-3 ve 5,61x10-3 cm2/dk olarak saptandı

New insight into anti-wrinkle treatment: Using nanoparticles as a controlled release system to increase acetyl octapeptide-3 efficiency

Botulinum neurotoxins represent a revolution in cosmetic science because of their extraordinary and long-term anti-wrinkle properties. Nevertheless, high neurotoxicity severely limits their usage. Therefore, design and validation of new non-toxic molecules which mimics the Botox are needed. Here, acetyl octapeptide-3 is used which mimics the effect mechanism of botulinum neurotoxin to reduces the depth of wrinkles, was chosen as an alternative molecule. Glutamic acid containing poly(2-hydroxyethyl methacrylate–methacryloylamidoglutamic acid) [p(HEMAG)] nanoparticles were synthesized for controlled release of acetyl octapeptide-3 to increase the efficiency on the related area. Scanning electron microscopy and atomic force microscopy were used to state the morphological characteristics of the synthesized nanoparticles, and the Fourier transform infrared was used to characterize chemical structures; additionally, the dimensional analysis was carried out by using a zeta-sizer device, and then, characterized nanoparticles were used for loading acetyl octapeptide-3. Time, pH, ionic strength, temperature and concentration experiments were performed to optimize the adsorption conditions of the acetyl octapeptide-3 to the nanoparticles. The maximum acetyl octapeptide-3 adsorption capacity onto nanoparticles was found 220.69 mg/g. The pH and temperature experiments were carried out to follow-up the release conditions of acetyl octapeptide-3-loaded nanoparticles. Lastly, cytotoxicity tests were done by using Alamar Blue method and Lactate Dehydrogenase (LDH) Assay. Our results imply that the developed nanocosmetic material is non-toxic, efficient and cost-effective and it is promising to use in anti-wrinkle treatment. Graphical abstract: [Figure not available: see fulltext.]

Poly(hydroxyethyl methacrylate-co-methacryloylglutamic acid) nanospheres for adsorption of Cd2+ ions from aqueous solutions

WOS: 000330311300001Poly(2-hydroxyethyl methacrylate-co-N-methacryloyl-(l)-glutamic acid) p(HEMA-MAGA) nanospheres have been synthesized, characterized, and used for the adsorption of Cd2+ ions from aqueous solutions. Nanospheres were prepared by surfactant free emulsion polymerization. The p(HEMA-MAGA) nanospheres were characterized by SEM, FTIR, zeta size, and elemental analysis. The specific surface area of nanospheres was found to be 1,779 m(2)/g. According to zeta size analysis results, average size of nanospheres is 147.3 nm with poly-dispersity index of 0.200. The goal of this study was to evaluate the adsorption performance of p(HEMA-MAGA) nanospheres for Cd2+ ions from aqueous solutions by a series of batch experiments. The Cd2+ concentration was determined by inductively coupled plasma-optical emission spectrometer. Equilibrium sorption experiments indicated a Cd2+ uptake capacity of 44.2 mg g(-1) at pH 4.0 at 25 A degrees C. The adsorption of Cd2+ ions increased with increasing pH and reached a plateau value at around pH 4.0. The data were successfully modeled with a Langmuir equation. A series of kinetics experiments was then carried out and a pseudo-second order equation was used to fit the experimental data. Desorption experiments which were carried out with nitric acid showed that the p(HEMA-MAGA) nanospheres could be reused without significant losses of their initial properties in consecutive adsorption and elution operations