Microspheres thermosensitive

Inada et al. succeeded in combining enzyme on synthesized magnetic particles. Thermosensitive magnetic particles that are useful for separation of enzyme and biomaterials have been reported. Furthermore, since magnetic polymeric microsphere particles were developed for labeling and separation of biocells, " studies into the applications of magnetic particles in the biology and medical fields are under way. ... 

The macromonomers were then copolymerized with styrene in ethanol. The resulting microspheres, with a PS core and poly(NIPAM) brushes, were thermosensitive [264-267]. 

The synthesis of stimuli-responsive polymer gel microspheres have been receiving growing attention [67-69,73]. Polymer microspheres that combine both temperature- and pH-responsive volume phase transitions have been elaborated, as reported by many authors [2,5-7,65,66]. Owing to their relatively rapid and easy magnetic separation, thermosensitive polymer magnetic microspheres could be widely used in biomedical and bioengineering, such... 

Among stimuli-responsive or thermoresponsive polymer microspheres, poly(N-isopropylacrylamidc) (PNIPA) was investigated most intensively. Cross-linked PNIPA is a thermosensitive hydrogel which undergoes a volume phase transition at its lower critical solution temperature (LCST) of around 34 °C. Several authors reported the synthesis of PNIPA microspheres [68-73]. 

BIODEGRADABLE MICROSPHERES BASED ON THE THERMOSENSITIVE PROPERTY OF PLCA-PEC-PLCA... 

Kwon YM, Kim SW. Biodegradable triblock copolymer microspheres based on thermosensitive sol-gel transition. Pharm Res 2004 21 339-343. 

Musial, W., Voncina, B., Pluta, J., Kokol, V., 2012. The Study of release of chlorhexidine from preparations with modified thermosensitive poly-N-isopropylacrylamide microspheres. Scientific World Journal 2012. 

Deng, Y., Yang, W., Wang, C. Fu, S. 2003, A novel approach for preparation of thermosensitive polymer magnetic microspheres with core-shell structure , Advanced Materials, vol. 15, no. 20, pp. 1729-1732. 

A block copolymer of poly(A-isopropylacrylamide) (PNI-PAAm) and PLA may combine the thermosensitive property of PNIPAAm and the biodegradable property of PLA. Polymeric micelles from such polymers can improve protein release properties. Temperature change can alter the hydro-philicity and conformation of PNIPAAm, which may affect the physicochemical properties of microspheres of the polymer. Amphiphilic block copolymers of P(NIPAAm-Z -LA) have been prepared by ROP of LA in toluene using Sn(Oct)2 as a catalyst and hydroxyl-terminated PNIPAAm, as depicted in Figure 4.6 [62]. Such copolymers have recently been synthesized by ROP of lactide using the two hydroxyl groups of 5, 5 -bis(2-hydroxyethyl-2 -butyrate)trithiocarbonate (BHBT). PLA-Z -PNIPAAm-Z -PLA was prepared by reversible addition-fragmentation chain transfer (RAFT) polymer-... 

Design and synthesis of multifunctional drug carriers based on luminescent rattle-type mesoporous silica microspheres with a thermosensitive hydrogel as a controlled switch. Adv,... 

The need for drug defivery systems to improve safety, efhcacy and patient compliance is well estabfished. There exist various drag delivery systems such as microspheres, nano particles, as well as environmentally sensitive systems [1-3]. Thermosensitive polymers are a subset of environmentally sensitive polymers which undergo a phase transition (sol-gel) when subjected to a change in temperature. 

Thermosensitive microspheres can be obtained by grafting of PNlPAAm onto or silica spheres. The volume... 

Recently core shell microspheres of NIPAM copolymer gels with sty-rene(St) have been prepared [33]. Because St-NIPAM copolymer microspheres prepared by soap-free emulsion polymerization have an imperfect core shell structure, seeded polymerization of NIPAM was carried out using the St-NIPAM microspheres as seeds to prepare uniform core shell microspheres. The particles obtained are thermosensitive gels and the adhesion between these particles and leukocytes has been investigated. Adsorption of proteins on the particles was also studied using PNIPAM gels [34]. 

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