Chemistry / Kimya

Permanent URI for this collectionhttps://hdl.handle.net/11147/4072

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Department: search.filters.department.İzmir Institute of Technology. Chemical EngineeringSubject: search.filters.subject.Chitosan

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Now showing 1 - 3 of 3
  • Book Part
    Citation - Scopus: 6
    Recent Advances in Chitosan-Based Systems for Delivery of Anticancer Drugs
    (Springer, 2020) Polat, Mehmet; Polat, Hürriyet; Polat, Hürriyet; Polat, Mehmet; 04.01. Department of Chemistry; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 04. Faculty of Science; 01. Izmir Institute of Technology
    Problems in transporting drug molecules to tumor sites in required dose or constitution lead to low efficacy and significant side effects. Shielding the drug molecules in micelles, liposomes, or nanoparticles is a major line of investigation to improve chemotherapeutic treatment. Though compatibility for proper envelopment of the drug and timely release at the tumor site are required of such a carrier, protecting its own physicochemical and morphological integrity during transport is another precondition. Because of its superior polymerization capability, biocompatibility, pH dependence, and charging characteristics, chitosan has been in the forefront of potential drug carriers. Numerous synthesis routes for chitosan-based nanocarriers have been suggested to the extent that a search of the literature published since 2000 with the keywords “novel + nano + chitosan” in the title results in 527 articles, indicating the bewildering quality and quantity of the new information. This review was carried out not only to peruse this large amount of work on chitosan-based anticancer drug delivery but also to extract manageable patterns from numerous synthesis routes. The main conclusion is that the synthesis methods suggested in literature can be combined into two main routes, and the degree of hydrophobicity of the drug determines which route should be followed. © Springer Nature Singapore Pte Ltd. 2019.
  • Article
    Citation - WoS: 16
    Citation - Scopus: 19
    Designing of Spherical Chitosan Nano-Shells With Micellar Cores for Solvation and Safeguarded Delivery of Strongly Lipophilic Drugs
    (Elsevier Ltd., 2017) Cihan, Esra; Polat, Mehmet; Polat, Mehmet; Polat, Hürriyet; 04.01. Department of Chemistry; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 04. Faculty of Science; 01. Izmir Institute of Technology
    Chitosan is a very effective biopolymer for drug delivery purposes due to its biocompatibility, positive charge and exceptionally pH sensitive degradability behavior in an aqueous medium. Nevertheless, its inability for dissolving lipophilic drug active material and the difficulties in controlling the size and shape of the synthesized particles in nanometer range are critical drawbacks in its effective use. In this study, a synthesis procedure which addresses both issues simultaneously is presented. The procedure is based on initial dissolution of lipophilic drug molecules within the hydrophobic cores of the micelles of a bio-compatible block-copolymer by ionic gelation and subsequent formation of a chitosan shell by polymerization around the micellar structures. Well-formed, hollow and perfectly spherical chitosan particles (nano-shells) in the 30–300 nm size range could be successfully manufactured. Characterization by STEM, TEM, AFM, FTIR and DLS, DLS-LDV techniques showed clearly that the drug was successfully incorporated into the chitosan structure. It was demonstrated that the particles enveloped the micelle(s) of a Pluronic copolymer (P-123) whose hydrophobic cores contained a strongly hydrophobic drug Probucol. The chitosan nano-shells are expected to act as an agent protecting the integrity of the drug-loaded micelles in the body fluid while providing a pH sensitive release medium. The drug uptake by the chitosan particles was very high. A very sharp increase in the amount of the drug released with a slight change in the acidity of the medium was an indication of the potential of the manufactured chitosan nano-shells as pH sensitive, target specific delivery vehicles for drug release.
  • Article
    Citation - WoS: 14
    Citation - Scopus: 15
    Chitosan-Immobilized Pumice for the Removal of As(v) From Waters
    (Springer Verlag, 2014) Turan, Dilek; Kocahakimoğlu, Cemre; Eroğlu, Ahmet Emin; Sofuoğlu, Sait Cemil; Eroğlu, Ahmet Emin; Sofuoğlu, Sait Cemil; 03.07. Department of Environmental Engineering; 04.01. Department of Chemistry; 03. Faculty of Engineering; 04. Faculty of Science; 01. Izmir Institute of Technology
    A novel sorbent, chitosan-immobilized pumice, has been prepared for the sorption of As(V) from waters prior to its determination by hydride generation atomic absorption spectrometry. The success of the immobilization has been checked with such characterization techniques as scanning electron microscopy, thermal gravimetric analysis, and elemental analysis. Points of zero charge of the sorbents were determined with potentiometric mass titration. Batch-type equilibration studies have shown that the novel sorbent can be employed at a wide pH range resulting in quantitative sorption (>90 %) at pH 3.0-7.0 and greater than 70 % sorption at pH >8.0. These results demonstrate the advantage of immobilizing chitosan onto pumice, because, under the same conditions, pumice displays <20 % sorption toward As(V), whereas chitosan gives approximately 90%sorption only at pH 3.0. The validity of the method was verified through the analysis of ultrapure, bottled drinking, and tap water samples spiked with arsenate; the respective sorption percentages of 93.2 (±0.7), 89.0 (±1.0), and 80.9 (±1.3) were obtained by batch-type equilibration. Arsenic sorption was also examined in the presence of common interfering ions resulting in competing effects of PO3- 4 and NO- 3on As(V) adsorption.