No abstract

The sorption of doxorubicin by hydrogeles obtained through cross-limking of polyacrylic acid with varied quantity (%, mass) of N, N-methylene-bis-acrylamide within pH = 1÷10 interval for 24 hours was performed. It revealed that protonation of active functional groups of hydrogel in acidic media (pH ≤ 4) impedes electrostatic interaction with identical charges in hydrogel and doxorubicin. A small degree of swelling at low pH of medium also impedes the penetration of molecule of antibiotic into internal pores of hydrogele. Note that pH changes toward alkaline medium, deprotonation and thereby negative charging of hydrogele surface leads to the sorption of positively charged molecule of doxorubicin. As the pH changes to the alkaline, the deprotonation of the hydrogel surface and, on the contrary, the negative loading that causes the easy sorption of positively charged doxorubicin molecule..On the other hand, the high swelling of hydrogel in alkaline medium also contributes to the increase of sorption level. Also, the nature of chemical interaction between hydrogel and antibiotic was examined by infrared spectroscopy methods, as well as by scanning electron microscopy. It found that the relation between the polymer and the doxorubicin occurs mainly due to hydrogen bond, electrostatic and hydrophobic interaction.

Orta molekul kütləsi 200 kDa olan qummiarabik və 40 kDa olan polietilenqlikol, eləcədə 200 kDa olan xitozan mühitində, Ag 0 nanohissəciklərinin alınması və stabilləşdirilməsi həyata keçirilmiş və alınmış gümüş nanohissəciklərinin quruluşları müxtəlif fiziki üsullarla tədqiq edilmişdir. Müəyyən olunmuşdur ki, qummiarabik və polietilenqlikol mühitində stabilləşən gümüş nanohissəciklərinin ölçüləri başlangıc maddələrin mol nisbəti, temperatur və reduksiya müddətindən asılı olaraq 12-17 nm aralığında, təbii poliaminosaxarid olan xitozandan istifadə etdikdə formalaşan gümüş nanohissəciklərinin ölçüləri isə reaksiya müddətindən asılı olaraq 8-11 nm aralığında dəyişir. İnfraqırmızı spektroskopiya üsulu ilə göstərilmişdir ki, gümüş nanohissəciklərinin stabilləşməsində qummiarabikin tərkibində olan-OH və-COOH qrupları, xitozan makromolekulunda isə-NH 2 və-OH qrupları aktiv iştirak edir. Polimer kompozitlərinin UV-Vis tədqiqinə əsasən Ag 0 nanohissəcikləri xarakterik səth plazmon rezonansı yaradırlar ki (410 nm), bu da Ag 0 nanozərrəciklərinin varlığını göstərir.

Over the past few decades, a significant increase in the use of heavy metals has led to an increase in the amount of metals in the aquatic environment. For living organisms, among heavy metals, copper (II) is one of the toxic metals and one of the most common environmental pollutants. Excessive concentrations of Cu2+ ions can cause various diseases and intoxications in humans. In this regard, the use of absorbents for the sorption of metals is both an economically and technologically efficient method. Quaternized natural polymer chitosan was used as a sorbent to study the sorption properties of copper (II) ion. During the research, the optimal conditions of the sorption process was determined, pH effect of the environment, initial concentration of the metal on the sorption process were studied. The sorption capacity of the synthesized sorbent towards the Cu (II) ion was studied and it was determined that the maximum sorption capacity equal to 255 mg/g was at pH=4. Moreover the influence of copper (II) ion concentration on the sorption process was studied. It was found that the sorption capacity and sorption degree of the sorbent increase with an increase in the concentration of the Cu2+ ion in the solution. It was determined that the maximum sorption capacity was 406 mg /g, which corresponds to the concentration of copper (II) ion, equal to 10∙10-2 mol/L. The results show that quaternized chitosan-based sorbent can be successfully used for the sorption of Cu (II) ion

Network polymer hydrogels with high swelling effect were synthesized by using of ultraviolet crosslinking, with crosslinking agent N,N'-methylene-bis-acrylamide with chitosan an average molecular weight of 100-300 kDa t. The amount of crosslinking agent made up 10% of chitosan weight. The gel structure was studied using FTIR and the mechanism of the cross-linking process identified. The sorption of levofloxacin on the obtained hydrogel was studied at different pH and the degree of sorption and the dependence of the sorption capacity of the hydrogel on the pH of the medium was studied. It found that the degree of sorption of hydrogel by levofloxacin is 90.4 % while the sorption capacity of gel increases as pH of the medium rises and at pH=8 it has the highest value equal to 8.9 mg/g.