Liposomes temperature sensitive

Figure 2. Liposomes with a specific character a), temperature-sensitive liposome b). target-sensitive liposome c). pH-sensitive liposome. Closed triangles and rectangles in lipid bilayer indicate amphiphiles which change the liposome s hydration with pH changes.

Needham D, Anyarambhatia G, Kong G, Dewhirst MW. A new temperature-sensitive liposome for use with mild hyperthermia characterization and testing in human tumor xenograft model. Cancer Res 2000 60 1197-1201. 

To this purpose, Fossheim et al. reported temperature sensitive liposomal Gd(III)-based probes (137-138). The composition of the liposomes was chosen in order to tune the temperature of transition between the gel-crystalline, where the liposome is water-impermeable, to the liquid-crystalline state, where water has free access to the interior of the liposome. This means that at temperatures below the transition, the relaxivity of the system is very low (paramagnetic contribution close to zero), whereas at higher temperature the Gd(III) complex ([GdDTPABMA(H20)] is the reference) is no longer silent... 

In a human tumor xenograft model, Kong et al.21 compared the antitumor effect of doxorubicin encapsulated in three types of liposome formulations, a nonthermosensitive liposome (NTSL), a traditional thermosensitive liposome (TTSL), and a low-temperature-sensitive liposome (LTSL). All three liposomes are sterically stabilized with PEG grafted on their surface. All the liposomes have a long circulation time and can accumulate selectively in tumor tissue. However, the lipid compositions of the three formulations are different. The NTSL was composed of saturated long-chain lipids such as hydrogenated soybean... 

Other functional liposomes are mainly stimuli-responsive liposomes. The pH-sensitive liposomes contain pH-sensitive lipids such as l,2-dioleoyl-vn-3-phosphatidylethanolamine (DOPE) showing an inverted hexagonal configuration in a low-pH environment and release entrapped drugs in the low-pH environment of tumor tissues due to liposomal membrane destabilization [89], Temperature-sensitive liposomes are prepared from special lipids such as DPPC whose phase transition temperature (Tc = 41°C) is proper to perform clinical anticancer therapy. When up to Tc, the fluidity of liposomal membranes increases sharply, followed by... 

Zou, Y. Yamagishi, M. Hoiikoshi, I. Ueno, M. Gu, X. Perez-Soler, R. Enhanced therapeutic effect against Uver W256 carcinoma with temperature-sensitive liposomal adriamycin administered into the hepatic artery. Cancer Res. 1993, 53, 3046-3051. 

Weinstein JN, Magin RL, Cysyk RL, et al. Treatment of solidL1210 murine tumors with local hyperthermia and temperature sensitive liposomes containing methotrexate. Cancer Res 1980 40 1388-1395. 

Kono K, Ozawa T, Yoshida T, Ozaki F, Ishizaka Y, Maruyama K, et al. Highly temperature sensitive liposomes based on a thermosensitive block copolymer for tumor-specific chemotherapy. Biomaterials 2010 27 7096-105. 

Landon, C. D., Park, J.-Y, Needham, D., Dewhirst, M. W. (2011]. Nanoscale drug delivery and Hyperthermia The materials design and preclinical and clinical testing of low temperature-sensitive liposomes used in combination with mild hyperthermia in the treatment of local cancer. Open Nanomed.J., 3,38-64. 

Yudina, A. de Smet, M. Lepetit-Coiffe, M. Langereis, S. Van Ruijssevelt, L. Smirnov, R Bouchaud, V. Voisin, R Gruell, H. Moonen, C. X. W Ultrasound-mediated intracellular drug delivery using microbubbles and temperature-sensitive liposomes. J. Controlled Release 2011, 155, 442- 8. 

Chen Q, Krol A, Wright A, Needham D, Dewhirst MW, Yuan F. Tumor microvascular permeability is a key determinant for antivascular effects of doxorubicin encapsulated in a temperature sensitive liposome. Int J Hyperthermia 2008 24 475-482. 

A temperature-sensitive liposome can be produced in two ways direct transition of lipid bilayers or incorporation of temperature-sensitive triggers. A liposome applied to tumors [75,76] can be made to release its contents rapidly and almost completely at the phase transition temperature, Tn. Temperature-sensitive liposomes have achieved a selectivity greater than 10-fold between heated and nonheated tumors in the delivery of methotrexate to tumors implanted in mice [77-79] or with cisplatin [80]. Hyperthermal targeting [81,82] was used in combination with radiation or chemotherapy with masked and temperature-sensitive liposomes [76,83-87]. 

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