Effect of quasi‐interpenetrating network of polyacrylamide and poly(N,N‐dimethylacrylamide) on separation of dsDNA fragments and basic protein using CE

Abstract

Quasi-interpenetrating network (quasi-IPN) of linear polyacrylamide (LPA) with low molecular mass and poly(N,N-dimethylacrylamide) (PDMA), which is shown to uniquely combine the superior sieving ability of LPA with the coating ability of PDMA, has been synthesized for application in dsDNA and basic protein separation by CE. The performance of quasi-IPN on dsDNA separation was determined by polymer concentration, electric field strength, LPA molecular masses and different acrylamide (AM) to N,N-dimethylacrylamide (DMA) ratio. The results showed that all fragments in Phix174/HaeIII digest were achieved with a 30 cm effective capillary length at -6 kV at an appropriate polymer solution concentration in bare silica capillaries. Furthermore, EOF measurement results showed that quasi-IPN exhibited good capillary coating ability, via adsorption from aqueous solution, efficiently suppressing EOF. The effect of the buffer pH values on the separation of basic proteins was investigated in detail. The separation efficiencies and analysis reproducibility demonstrated the good potentiality of quasi-IPN matrix for suppressing the adsorption of basic proteins onto the silica capillary wall. In addition, when quasi-IPN was used both as sieving matrix and dynamic coating in bare silica capillaries, higher peak separation efficiencies, and better migration time reproducibility were obtained.

Brush‐like copolymer as a physically adsorbed coating for protein separation by capillary electrophoresis

“…Figure 4 shows the proposed model of adsorption of PEGMA‐DMA copolymer onto capillary surface. Compared with the hydrogen bonding, the hydrophobic interaction is more important to improve the adsorbing capability and the stability of copolymer coating 44, 45.…”

Polymer sieving matrices in microanalytical electrophoresis

“…112 For DNA separations in CE formats, various quasiIPNs have been investigated including: LPA + PVP, 114 PDMA + PVP, 113 poly(N-acryloyl-2-amino-2-hydroxymethyl-1,3-propanediol) + PVP, 112 and LPA + PDMA. 94 In addition to reduced analyte adsorption and lowered viscosity, higher separation efficiency was observed as compared to homopolymers of a similar molecular mass, aer carefully tuning molecular mass and ratio of two incompatible polymers. high sieving capacity of LPA and the dynamic surface coating properties of PDMA, separation efficiencies ranged from 3.02 to 4.29 Â 10 5 plates per m. The separation efficiency of the IPN containing a low molecular mass LPA (<1 MDa) was higher than that of a homopolymer LPA of much higher molecular mass (>3 MDa).…”

“…54 Reagents for this purpose include polymers of acrylamide 60,80 and acrylamide derivatives such as PDMA 34 and PHEA (poly-N-hydroxyethylacrylamide), 81 polysaccharide and its derivatives such as dextran, 82 Lastly, novel sieving matrices that offer complex properties are being more widely adopted. These include: thermally responsive polymers, 93 interpenetrating networks (IPN) 94 and carbon nanotube (CNT) modied polymers (see chapter 5 also for more detail). 95 While somewhat complicated to prepare, all of these polymers were intended to prevent analyte adsorption, facilitate polymer loading and replacement, and afford highperformance separations.…”

Electrophoretic and electrochromatographic separation of proteins in capillaries: An update covering 2007–2009

“…Quasi‐interpenetrating network (quasi‐IPN) of linear polyacrylamide with low molecular mass and poly( N,N ‐dimethylacrylamide), which is shown to uniquely combine the superior sieving ability of linear polyacrylamide with the coating ability of poly( N,N ‐dimethylacrylamide), has been synthesized for application in dsDNA and basic protein separation by CGE 64. The EOF measurement results showed that quasi‐IPN exhibited good capillary coating ability, via adsorption from aqueous solution, efficiently suppressing EOF.…”