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Vesicles can be used for the compartmentalization of chemical reactions and self‐assembly of reaction partners. This minireview highlights recent advances in biomimetic and light‐induced energy conversions with liposomes and polymersomes, relevant in the context of energy transfer, electron transfer, photocatalysis and artificial photosynthesis. Lipid bilayer membranes are ubiquitous in natural chemical conversions. They enable self‐assembly and compartmentalization of reaction partners and it becomes increasingly evident that a thorough fundamental understanding of these concepts is highly desirable for chemical reactions and solar energy conversion with artificial systems. This minireview focusses on selected case studies from recent years, most of which were inspired by either membrane‐facilitated light harvesting or respective charge transfer. The main focus is on highly biomimetic liposomes with artificial chromophores, and some cases for polymer‐membranes will be made. Furthermore, we categorized these studies into energy transfer and electron transfer, with phospholipid vesicles, and polymer membranes for light‐driven reactions., publishedVersion

Amaç: Bu çalışmada, güçlü antioksidan etkisi bilinen kafeik asitin kaplı olmayan ve kitozan kaplı lipozom formülasyonlarının geliştirilmesi, in vitro karakterize edilmesi, salım ve hücre geçiş çalışmaları yapılarak kitozan kaplamanın, kafeik asitin deriden geçişini artırmadaki katkısının incelenmesi ve bu sayede uzatılmış antioksidan etkinliğinin değerlendirilmesi amaçlanmıştır. Gereç ve Yöntemler: Yeni geliştirilen kitozan kaplı ve kaplı olmayan lipozomların karakterizasyon parametreleri (partikül büyüklüğü ve dağılımı, zeta potansiyel, polidispersite indeksi ve yükleme etkinliği) ölçülmüş, farklı kitozan konsantrasyonları ile hazırlanan kaplı lipozomlardan optimum formülasyon belirlenmiştir. In vitro salım çalışmaları yapılmış ve formülasyonların stabiliteleri tayin edilmiştir. Hücre kültürü çalışmaları kapsamında, fare fibroblast hücre hattı (L929) kullanılarak sitotoksisite testi ve hücre geçiş çalışmaları yapılmıştır. Geliştirilen formülasyonların antioksidan aktivitesi, 1,1-difenil-2-pikrilhidrazil (DPPH●) ve (2,2-Azino-bis3-etilbenzotiyazolin-6-sülfonik asit) (ABTS●+) radikal süpürücü etki ile belirlenmiştir. Bulgular: Kafeik asit yüklü lipozomal formülasyonlar başarıyla geliştirilmiş ve karakterize edilmiştir. Toksisite çalışmasına göre, kafeik asit çözeltisi (250 µg/mL ve altındaki konsantrasyonlar) ve kafeik asit yüklü geliştirilen lipozomal formülasyonlar toksik bulunmamıştır. In vitro salım ve hücre geçiş çalışması sonucu elde edilen kafeik asit miktarlarının, DPPH● ve ABTS●+ radikallerini süpürücü etkisi ispatlanmıştır. Sonuç: Sonuç olarak, toksik etkisi bulunmayan, yeni, kafeik asit yüklü kaplı olmayan ve kitozan kaplı lipozomlar başarıyla geliştirilmiş, kitozan kaplamanın deriye olan yüksek afinitesi ve uzatılmış antioksidan etkinliği kanıtlanmış ve topikal uygulama için potansiyel oluşturabileceği düşünülmektedir., Aim: In this study, it was aimed to develop uncoated and chitosan-coated liposome formulations containing caffeic acid which has a strong antioxidant effect, to characterize in vitro and to investigate of the contribution of chitosan coating to increase the permeation of caffeic acid through by skin release and permeation studies, and to evaluate its sustained antioxidant effect.Material and Methods: Characterization parameters (particle size and distribution, zeta potential, polydispersity index and ancapsulation efficiency) were measured, The optimum formulation was determined from coated liposomes prepared with different concentrations of chitosan. In vitro release studies of newly developed chitosan coated and uncoated liposomes were performed and stabilities of formulations were determined. Within the scope of cell culture studies, cytotoxicity test and cell permeation study were performed with using L929 mouse fibroblast cell line. Antioxidant activities of liposomal formulations were measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH●) ve 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS●+) radical scavenging effect. Results: Caffeic acid loaded liposomes were developed successfully and characterized. According to the toxicity study, caffeic acid solution (250µg/mL and below concentrations) and liposomal formulations were not toxic. The scavenging effects of DPPH● and ABTS●+ radicals of the amounts of caffeic acid obtained as an end of result of the in vitro release and cell permeation studies were proven.Conclusion: In conclusion, novel uncoated and chitosan coated liposomes containing caffeic acid have been successfully developed, high affinity to the skin of chitosan coating and the sustained antioxidant effects of liposomes were proven and are thought to be potential for topical application.

Breast cancer is one of deadliest diseases in the world. Turmeric extract was known to have antiproliferative activity. To minimize its toxicity, turmeric extract was encapsulated with liposome, a vesicle lipid bilayer that was functioned as cancer drug carrier in body. This research aimed to determine encapsulation effect of turmeric extract against antiproliferative activity in T47D breast cancer cells through in vitro assay. Liposomes was made using thin layer method and particle size was reduced by extrusion. Materials that was used phosphatidylcholine, cholesterol, and turmeric extract. Optimization of liposomes was made in three formulations with different extract concentrations. The most optimal formulation was formulation with less extract and physical parameters which have smallest precipitates and longest settling time. Evaluation liposome particle size and zeta potential were used DLS, morphology was used TEM, and entrapment efficiency was used dialysis. The most optimal formulation was tested their antiproliferative activity compared with not encapsulated extracts used 3-(4,5-dimethylazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The result showed that there was antiproliferative activity in encapsulated extracts. IC50 encapsulated extracts was 45.762 μg/ml and IC50 extracts was 36.399 μg/ml. Liposome particle size was below 445 nm. Zeta potential was -7.51 mV. Morphology was LUV and MVV. Entrapment efficiency was 63.80%. It could be concluded that encapsulation of turmeric extract into liposome could reduce its toxicity against cancer cells.

Liposome-based drug delivery systems hold great potential for cancer therapy. The aim of this study was to design a nanodevice for targeted anchoring of liposomes (with and without cholesterol) with encapsulated anticancer drugs and antisense N-myc gene oligonucleotide attached to its surface. To meet this main aim, liposomes with encapsulated doxorubicin, ellipticine and etoposide were prepared. They were further characterized by measuring their fluorescence intensity, whereas the encapsulation efficiency was estimated to be 16%. The hybridization process of individual oligonucleotides forming the nanoconstruct was investigated spectrophotometrically and electrochemically. The concentrations of ellipticine, doxorubicin and etoposide attached to the nanoconstruct in gold nanoparticle-modified liposomes were found to be 14, 5 and 2 µg•mL(-1), respectively. The study succeeded in demonstrating that liposomes are suitable for the transport of anticancer drugs and the antisense oligonucleotide, which can block the expression of the N-myc gene. Systémy transportu léčiv pomocí liposomů udržují velký potenciál pro léčbu rakoviny. Cílem této studie bylo navrhnout nanozařízení pro cílené ukotvení liposomů (s a bez cholesterolu) s enkapsulovanými protinádorovými léky a k povrchu připojeným antisense oligonukleotidem pro gen n-myc. K dosažení tohoto hlavního cíle byly připraveny liposomy s enkapsulovaným doxorubicinem, ellipticinem a etoposidem. Byly charakterizovány měřením intenzity fluorescence, zatímco účinnost enkapsulace byla odhadována na 16 %. Proces hybridizace jednotlivých oligonukleotidů tvořících nanokonstrukt byl sledován spektrofotometricky a elektrochemicky. Koncentrace ellipticinu, doxorubicinu a etoposidu připojených k nanokonstruktu v liposomech modifikovaných zlatými nanočásticemi byly 14, 5 a 2 µg•ml(-1). Autorům studie se podařilo prokázat, že liposomy jsou vhodné pro transport protinádorových léků a antisense oligonukleotidu, který může blokovat expresi n-myc genu.