Preparation Of Poly(acrylamide)Cryogel Beads And Puerarin Solid Lipid Nanoparticles Based On Microchannels

Microchannels have advantages in preparation of monodisperse microparticles and nanoparticles due to their good stability,high mass transfer rate and good controllability.Supermacroporous cryogels can capture biomolecules directly from microbial fermentation feedstocks at high flow velocities,expected to be widely applied in bioseparation areas,with the merits of biocompatibility,physical and chemical stability.Solid lipid nanoparticles is a new drug delivery system,which can control drug release,prevent drug from leakage,thus improve the drug bioavailability.In this paper,we use liquid flow-focusing microchannel system with a cross-junction to prepare poly(acrylamide)cryogel beads.The influences of the flow rates of the oil and the aqueous phases on the diameter of the obtained cryogel beads were investigated.After filling into the chromatography column,cryogel beads were grafted in-situ with sulfo-group and anion-exchange cryogel beads were obtained.Separation of lysozyme from chicken egg white solution using the anion-exchange cryogel beads was carried out.The chromatographic behaviour of lysozyme before and after the second grafted was also studied.Using nitrogen as the gas phase,puerarin as model drug,puerarin solid lipid nanoparticles were prepared in microchannel system and major factors were investigated.The results showed that monodisperse poly(acrylamide)cryogel beads could be prepared using microchannel system.The diameters of the cryogel beads decreased with the increase of the oil phase flow rate,while increased with the increase of the aqueous phase flow rate.The cryogel beads were spherical in shape and suitable for bioseparation due to the inner highly interconnected large pores.The mean diameter of poly(acrylamide)cryogel beads filled in the first chromatography column was 1248 ?m.The filling chromatographic bed has high axial dispersion coefficient and permeability after the graft polymerization.The isolation of lysozyme from chicken egg white with one-step elution was introduced by anion-exchange chromatography at the velocities of 0.5 to 15 cm/min after the first grafted.The adsorption capacities were decreased with the increase of the velocity.The purity of the obtained lysozyme was about 78%to 92%,while this date was about 88%with two-step elution under the velocity of 1 cm/min.The activity of the obtained lysozyme was high as 16000 U/mg,and the activity recovery was 86%.Using lysozyme as a model protein,the adsorption capacities and recoveries were decreased with the increase of the velocity(0.5?15 cm/min).After the secondly grafted,the adsorption capacities increased by 15.9%?71%,and the recoveries increased by 5.59%?30.27%.The mean diameter of composite poly(acrylamide)cryogel beads filled in the second chromatography column was 873 ?m.The adsorption capacities and the recoveries were high than those of the first chromatography column filled with big diameter of poly(acrylamide)cryogel beads under the velocities of 2?10 cm/min.Puerarin solid lipid nanoparticles could be prepared using microchannel system.The diameter decreased with the increase of the aqueous phase flow rate,while increased with the increase of the oil phase flow rate,the gas phase flow rate and the concentration of hydrogenated coconut oil glycerides(Softisan 100).The puerarin concentration has great infiuence on the drug loading and the encapsulation efficiency,they all increased with the increase of the puerarin concentration.