Microgels properties swelling

The ODN adsorption onto cationic microgel poly(N-isopropylacrylamide) particles was reported to be dramatically affected by the salinity of the incubation medium [9] as illustrated in Fig. 6. The observed result was related to (i) the reduction in attractive electrostatic interactions between ODN molecules and the adsorbent and (ii) the drastic effect of ionic strength on the physico-chemical properties of such particles [17, 27]. In fact, the hydrodynamic size, the swelling ability, the electrokinetic properties, and the colloidal stability are dramatically affected by pH, salt concentration, and the medium temperature [27]. 

Investigations by DLS measurements of composite particles indicated that the original thermosensitive properties of the PNIPA network are not suppressed by the incorporation of metal particles into the network. That is, the shrinking and re-swelling of microgel is not hampered by the incorporation of metal nanoparticles into the network. The metal composite particles show similar volume transition temperature as the carrier particle at 32°C, which is in excellent agreement with previous findings on these systems as shown in Fig. 7 [64, 65], This indicates... 

Our group has demonstrated that the catalytic properties of immobilized enzymes can be manipulated by the temperature-dependent swelling behavior of the microgel. The hydrolytic activity of adsorbed and native P-D-glucosidase was determined as a function of temperature. Desorption of immobilized enzyme upon... 

Microgels can be produced by the mixing and emulsification of two different polymer solutions that can react to form cross-linked microgel particles that are monodisperse and have predictable swelling properties [8]. An example of this is the use of aldehyde and hydrazide-functionaUzed carbohydrates where heating or UV irradiation can be used for gelation. 

Swelling properties of water-soluble microgels can be modified by copolymerization with hydrophobic comonomers. In such cases, the desaiption of the sweUing ratio as a function of temperature by the Flory-Rehner theory was only partially satisfying and fails for higher comonomer contents. ... 

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