PL aquagel

Examples PSS SDV PL Gel Styragel TSK-H Shodex A,K PSS HEMA Shodex PSS HEMA Bio PSS Suprema PL Aquagel UltraHydrogel TSK-PW Shodex OH (ionic SO,H, amides) Very many ... 

The field of aqueous SEC is of growing interest and also represents an area of active development by several companies, with Polymer Laboratories included. In this area, contrary to the organic SEC scenario, a variety of polymer chemistries are employed in the preparation of the column packing materials. This fact alone makes the practice of aqueous SEC more difficult than its organic counterpart and requires the suppliers of such columns to offer a good level of technical support to the column user. This chapter outlines the characteristics and applications of PL aquagel-OH aqueous SEC columns. 

PL aquagel-OH consists of macroporous, hydrophilic particles that exhibit a polyhydroxyl functionality. The columns exhibit extremely good stability during operation they will tolerate an operating pressure up to 140 bar and an eluent composition containing organic modifier up to 50% by volume and eluent pH in the range of 2-10. 

FIGURE 12.7 SEC calibration curves for PL aquagel-OH columns (300 X 7.5 mm), eluent water at 1.0 ml/min, polyethylene oxide/glycol calibrants. 

Polymer type Typical examples Suitable eluent for use with PL aquagel-OH columns... 

SW series and Alltech Macrosphere series), hydroxylated methacrylate (e.g., TosoHaas TSK PW series. Waters Ultrahydrostyragel, Shodex OHPak), functionalized styrene/DVB (Polymer Laboratories PL aquagel-OH), poly(vinyl alcohol) (Shodex OHPak), and others. 

It is also useful to note that the hydrophilic alcohol coated stationary phases originally designed for size exclusion chromatography such as Zorbax GF250 and PL-aquagel also work well as normal phase media. The advantage of these lies in the increased stability of the stationary phases at high pH. 

HEP) than PS. It is proposed that size exclusion continues to dominate separations of PBMA for the mobile phases given previously. For PL Aquagel P3 packing in the second column, resolution of homopolymer peaks was obtained with mobile-phase compositions of 55 45 (THF-HEP) and 30 70 (THF-IP). However, these results are not as easy to interpret as the observations for PLgeL because both PS and PBMA homopolymer peaks appear to be influenced by adsorption on PL Aqua-gel P3 as the HEP concentration is increased and because there is a low difference in peak retention volumes between these peaks for elutions with THF-IP, requiring a very high fraction of IP to achieve peak resolution. 

Finally, the following SEC columns, which have been introduced in recent years, have been demonstrated by the vendors to be successful with PVP Jordi DVB Glucose BR linear column [in dimethyl sulfoxide (DMSO)], PL aquagel-OH column (in 0.1M-0.3M salt-buffer with 20% methanol) PSS Suprema column (in O.IM Tris pH 7 buffer), and PSS SDV column (in DMAC, 0.1% LiBr) [11-13]. 

Aquatic HS PL Aquagel-OH 30 SEC column 80/20 (v/v) Water/methanol mixture with 10 mM NH4HCO3 DAD and ESI-MS detectors Structure of HS 45... 

SEC calibration using polyethylene oxide (PEO) and polysaccharide (PSAC) standards, eolumn PL aquagel-OH 50 300 x 7.5 mm, eluant water, flow rate 1 ml/minute, detector RI. 

PL aquagel - OH 50, 10 pM 200 -100,000 Water soluble polymers Pol)winyl alcohol, polyacrylic acid, poly 2-vinyl pyridine... 

PL aquagel - OH 60,10 pM 100,000-2x107 Water soluble polymers Polyacrylamides, polyethylene oxides... 

The molecular weights of the hemicelluloses and their carboxymethylated derivatives were determined by GPC on a PL aquagel-OH50 column (3007.7 mm. Polymer Laboratories Ltd.). Detection was achieved with a Knauer differential refractometer. The weight of carboxymethylated hemicelluloses became lower than that of native hemicelluloses (26800 g.moP), as the Mw range from 12213 to 15312 g/mol. In addition, carboxymethyl hemicelluloses had a relatively low index of polydispersity (2.75-2.87), which indicated that the molecular weights of hemicellulosic derivatives were more uniform [72]. 

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