2013 4 Vol. 31 No. 4 April 2013 Chinese Journal of Chromatography 322 ~ 328 DOI 10. 3724 /SP. J. 1123. 2013. 03012 1* 1 2 1 2 1 2 1 1* 1. 116023 2. 100049 POSS Bu-POSS POSS POSS-MA / 400 Bu-POSS-co- POSS-MA POSS-MA POSS-MA clc POSS POSS-MA POSS - O658 A 1000-8713 2013 04-0322-07 Preparation and modification of polyhedral oligomeric silsesquioxane-containing hybrid monolithic capillary columns OU Junjie 1* LIN Hui 1 2 LIU Zheyi 1 ZHANG Zhenbin 1 2 DONG Jing 1 ZOU Hanfa 1* 1. CAS Key Laboratory of Separation Science for Analytical ChemistryDalian Institute of Chemical Physics Chinese Academy of SciencesNational Chromatographic R. & A. CenterDalian 116023China 2. University of Chinese Academy of SciencesBeijing 100049China Abstract Two kinds of hybrid monolithic capillary columns were prepared via free radical polymerization. First the hybrid monolithic column was in situ fabricated by using two polyhedral oligomeric silsesquioxanes POSS POSS-methacryl substituted cage mixturen = 81012 POSS-MA and POSS- 1-propylmethacrylate -heptaisobutyl substituted Bu-POSS as crosslinker and monomerrespectively in the presence of porogenic solvents propanol /PEG400 and initiator azodisobutyronitrile. Second the hybrid monolithic column was similarly prepared by using POSS-MAas sole monomer under the same conditions. The resulting two kinds of hybrid monolithic columnspoly Bu-POSS-co- POSS-MA and poly POSS-MA were characterized and applied for the separation of alkylbenzenes by capillary liquid chromatography clc showing good mechanical stability and reproducibility. Additionally the poly POSS-MA monolith could be easily modified with other organic monomerssuch as stearyl methacrylate SMA and benzyl metacrylate BeMA with the presence of methacryl groups on the surface of the poly POSS-MA monolith. Compared with the raw poly POSS-MA monoliththe postmodified poly POSS-MA monolith exhibited higher column efficiency and better selectivity. This simple process of using POSS reagents via free radical polymerization is providing a novel way for the preparation of the organic-silica hybrid monolithic columns. *. Tel 0411 84379576 E-mail junjieou@ dicp. ac. cn Tel 0411 84379610 E-mail hanfazou@ dicp. ac. cn. 2012CB910601 21175133 21021004. 2013-03-04
4 323 Key words polyhedral oligomeric silsesquioxane monolithic column organic-silica hybrid capillary liquid chromatography capillary-hplcclc nm micro-hplcμ-lc HPLC 24 POSS HPLC clc POSS POSS- n = 81012POSS-MA POSS- 1- MS - Bu-POSS 25 26 27 POSS 1-4 clc CEC clc clc POSS POSS clc 1 1. 1 5 6 clc HPLC Agilent 1100 Hewlett-Packard 7 8 9 10 model 7125Rheodyne Knauer 11-13 K-2501 CT-21 Malik 14 - sol-gel - POSS POSS-MA Bu-POSS 1 Acros stearyl methacrylatesma benzyl metacrylatebema 400 esquioxaneposs 50 μm i. d. 375 μm o. d. 75 μm i. d. 375 μm o. d. R n SiO 1. 5 n R Milli-Q n 4 POSS 1. 2 1 ~ 3 clc T ph PEG400 380 ~ 420 γ- γ- C8 MAPS ribonuclease B 15-18 bovine serum albuminbsa c cytochrome c myoglobin - insulin ovalbumin Sigma lysozyme 19-23 azodisobutyronitrileaibn TFA polyhedral oligomeric sils-
324 31 50 μm i. d. 1 375 μm o. d. 95 cm 1. 4. 1 Bu-POSS POSS-MA 1 /500 Monolith Ⅰ 50 μm i. d. 375 μm o. d. 6 cm POSS-MA 1 mg AIBN 214 nm 320 μl 160 μl 400 15 min A TFA / 1 g /L B TFA / 1 g /L 0 ~ 30 min20% B ~ 60% 55 B 500 nl /min Darcy 18 h 20 B 0 = FηL / πr 2 ΔP F η L r ΔP Monolith Ⅰ 1. 3 0. 1 mol /L NaOH 1. 4. 2 POSS-MA Monolith 75 μm i. d. 375 μm o. d. 2 h Ⅱ 30 min 0. 1 mol /L HCl 12 h AIBN 320 μl 160 μl 50% 400 1. 4. 1 γ-maps Monolith Ⅱ 45 16 h 1. 4. 3 Monolith Ⅲ 1. 4. 2 20 mg Bu-POSS 100 mg γ-maps 120 mg POSS-MA 1 mg Monolith Ⅱ 30 min SMA Be- 1. 4 POSS MA AIBN 10 /1 /90 15 /1 /85 Fig. 1 1 POSS Schematic fabrication of POSS-containing hybrid monoliths via two routes i. formation of the monoliths ii. post-modification.
4 325 v /w /v Monolith Ⅱ 400 55 18 h Mon- olith Ⅲ 2 2. 1 POSS POSS POSS 320 /160 1 B 5. 18 10-14 m 2 2c d Bu-POSS POSS-MA 100 mg POSS-MA 20 Monolith I mg Bu-POSS 320 μl 160 μl 400-1 mg AIBN Bu-POSS-co- POSS-MA Monolith Ⅰ POSS-MA POSS-MA - - - - - 1 C 1 A 5. 93 4. 25 10-14 m 2 10-14 m 2 2a b 2e f -Bu-POSS-co-POSS-MA 2 POSS Fig. 2 Scanning electron microscope photographs of POSS-containing hybrid monoliths prepared under different conditions ab. column A cd. column B e f. column C gh. column D. Preparation conditions are the same as in Table 1.
326 31-400 3. 85 10-14 m 2 POSS-MA 2g h D POSS-MA Monolith Ⅱ 320 /160 1 D Table 1 1 POSS Compositions of polymerization mixtures for the preparation of POSS-based hybrid monolithic columns Column * POSS-MA /mg Bu-POSS /mg Porogenic solvents Permeability / 10-14 m 2 A 90 30 50 μl tert-pentanol 310 μl dedacanol 5. 93 B 100 20 320 μl propanol 160 μl PEG400 5. 18 C 120-320 μl propanol 160 μl butanediol 4. 25 D 120-320 μl propanol 160 μl PEG400 3. 85 * Preparation conditions polymerization temperature55 AIBN1 mg. 2. 2 POSS POSS-co-POSS-MA Bu-POSS-co- -Si-O-Si- POSS-MA POSS-MA clc Bu-POSS-co-POSS-MA 100 nl /min 1. 0 μl /min van Deemter 3b 1 400 kpa 14 000 kpa r = 0. 999 clc 30. 2 μm 33 100 N /m clc 4a 70% 5 POSS-MA clc RSD 2. 2% n = 3 2. 3% n = 3 POSS-MA RSD 2. 8% n = 3 2. 5% n = 3 RSD 5. 2% n = 3 4. 9% n = 3 POSS-MA 2. 3 POSS POSS-MA clc -Si-O-Si- 4b clc POSS-MA van Deemter 4b 3 4 3a 70% 5 Bu-POSS-co-POSS- MA clc 36. 1 μm 27 700 N /m POSS-MA Bu- POSS- 3 B a b van Deemter Fig. 3 a Chromatogram of alkylbenzenes and b van Deemter plot on the hybrid monolithic column B with clc Conditions column dimension30 cm 75 μm i. d. mobile phaseacn /H 2 O 70%v /v flow rate400 nl /min for a. Peaks 1. thiourea 2. benzene 3. toluene 4. ethylbenzene 5. propylbenzene 6. butylbenzene.
4 327 4 a b SMA c d SMA D van Deemter Fig. 4 Chromatograms of alkylbenzenes and van Deemter plots on the hybrid monolithic column D a and b before and c and d after modification Conditions column dimension30 cm 75 μm i. d. mobile phaseacn /H 2 O 70%v /v flow rate400 nl /min for a. Peaks 1. thiourea 2. benzene 3. toluene 4. ethylbenzene 5. propylbenzene 6. butylbenzene. POSS-MA 7 SMA BeMA 5% 10% 4c clc SMA POSS- MA POSS- MA 5 5a 15% 7 BSA POSS-MA 5b 7 SMA POSS- MA van Deemter 7 4d 4d clc BSA BSA 23. 9 μm 41 800 N /m Monolith Ⅱ SMA SMA Monolith Ⅲ 5c 7 BeMA 50. 9% SMA POSS-MA clc POSS-MA 5c 7 5b c SMA BeMA 2. 4 POSS-MA clc POSS-MA POSS-MA clc 5a MA clc 5b POSS-MA
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