Injectable biodegradable polymeric system for preserving the active form and delayed-release of camptothecin anticancer drugs

Mert, Olcay
Demir, Ayhan Gürbüz
One of the most challenging problems for camptothecin (CPT) family anticancer drugs (i.e. topotecan (TPT)) is the conversion of the active lactone ring into an inactive toxic carboxylate form under physiological conditions (pH = 7.4) in the body. Therefore, a simple platform based on thermosensitive PLLA-mPEG gels was designed to maintain TPT and CPT in lactone form, especially for brain tumor therapies. A high stabilization of the lactone species CPT and TPT within gel (>95%), efficient versatile homogenous drug loadings at 0.015%, 1%, and 10%, and the sustained-release of CPT and TPT over three weeks were all successful. The stabilization mechanism of drugs with gel was elucidated by ATR-FTIR, confocal and light microscopy. The cytotoxic efficacy of TPT in the PLLA-mPEG platform (PLLA-mPEG-TPT) was evaluated on LLC-1 and 4T1 cancer cell lines. In vivo, the administration of PLLA-mPEG-TPT to mice with breast tumors resulted in a significant reduction in tumor size and better survival percentages.


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Gurel, I; Arica, MY; Hasırcı, Vasıf Nejat (1997-01-01)
Immobilization of glucose oxidase and urease in hydrogels of 2-hydroxyethyl methacrylae, and N-vinyl pyrrolidone (NVP) was achieved by irradiation (using UV kand gamma-rays). The effect of radiation on entrapment efficiencies, retention of activities and swelling rates was obtained. To optimize the system, duration of exposure, reaction temperature, co-monomer concentrations, initiator and cross linker compositions were varied. The repeated reusability of the generated products was also tested. It was found...
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The synthesis of (1S,2R)-1-amino-2-indanol, a key component of HIV protease inhibitor is accomplished in four steps starting from indanone efficiently and with high levels of diastereo- and enantioselectivity. The starting material is converted into 2-acetoxy-1-indanone involving Manganese (III) acetate oxidation. The 2-acetoxyketone is hydrolyzed to 2-hydroxy-1-indanone enantioselectively using Rhizopus oryzae. Selective reduction of 2-hydroxyoxime derivative, derived from the 2-hydroxyketone, gives the am...
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Simvastatin is one of the most frequently prescribed statins because of its efficacy in the treatment of hypercholesterolemia, reducing cardiovascular risk and related mortality. Determination of its side effects on different tissues is mandatory to improve safe use of this drug. In the present study, the effects of simvastatin on molecular composition and structure of healthy rat livers were investigated by Fourier transform infrared and Raman imaging. Simvastatin-treated groups received 50 mg/kg/day simva...
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Resveratrol is among the best-known secondary plant metabolites because of its antioxidant, anti-inflammatory, and anticancer properties. It also is an important allelopathic chemical widely credited with the protection of plants from pathogens. The ecological role of resveratrol in natural habitats is difficult to establish rigorously, because it does not seem to accumulate outside plant tissue. It is likely that bacterial degradation plays a key role in determining the persistence, and thus the ecological...
Enantioselective synthesis of new chiral 2-aziridinyl phosphonates and studies of their biological activities
Doğan, Özdemir; Beksultanova, Nurzhan; ALTANLAR, NURTEN; Simsek, Duygu; KARABIYIK, HASAN (2017-02-15)
A new series of chiral aziridinyl phosphonates has been synthesized and evaluated for antibacterial and antifungal activities. For the synthesis, a Gabriel-Cromwell reaction was used to form aziridinyl phosphonates in 52-83% yield. In order to evaluate antibacterial and antifungal activities, MIC values were measured. Although most of the compounds showed insignificant activity, two of them provided low to moderate antifungal activity.
Citation Formats
O. Mert, G. ESENDAĞLI, A. DOĞAN, and A. G. Demir, “Injectable biodegradable polymeric system for preserving the active form and delayed-release of camptothecin anticancer drugs,” RSC ADVANCES, pp. 176–185, 2012, Accessed: 00, 2020. [Online]. Available: