can be immobilized to any appropriate materials. We foresee
promising application of this affinity ligand in the areas of
proteomics, metabolomic and glycomics.
This study was supported by the Fundamental Research
Funds for the Central Universities (Grant No. 1093020506).
The authors also acknowledge the financial support from the
National Natural Science Foundation of China (Grant No.
21075063), the Ministry of Science and Technology of China
(Grants No. 2008DFA01910 and 34-8), and the Ministry of
Education of China (Grant No. NCET-08-0270).
Notes and references
Fig. 4 MEKC analysis of urine sample (a) and extracted components
by the boronate affinity monolithic column (b). Peak identity: 5,
cytidine; 12, guanosine; other, unknown.
z Selected data for 4. 1H NMR (500 MHz, CDCl3): d 7.48 (1H, d, J =
8 Hz), 6.69 (1H, s), 6.62 (1H, d, J = 4.5 Hz), 3.91 (2H, s), 3.79 (2H, s),
2.53 (6H, s), 1.32 (12H, s); 13C NMR (500 MHz, CDCl3): d 135.5,
114.6, 113.7, 77.0, 62.8, 44.5, 25.7; 11B NMR (500 MHz, CDCl3): d
22.54; MS(EI+) m/z [275.2 (4.82), 276.2 (18.72), 277.2 (0.24)] (M+).
The retention mechanism on the boronate affinity column was
further confirmed with quinol and catechol as analytes. The
boronate affinity monolithic column exhibited specific affinity
to catechol at and above pH 5.5 (Fig. S18, ESIw).
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(cytidine) and 12 (guanosine) confirm the specific affinity of
the monolithic column to cis-diol compounds in real sample
environments. With using the boronate affinity monolithic
capillary as an extraction column, we are establishing a two-
dimensional (2D) nano-LC-MSn platform for metabolomic
analysis of human urinary nucleosides, which will be published
elsewhere.
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In conclusion, a new Wulff-type boronate, 3-(dimethylamino-
methyl)aniline-4-pinacol boronate, was designed and synthesized.
The compound was attached to a polymer monolithic column
through nucleophilic addition reaction. The resulting boronate
affinity monolithic column showed specific affinity towards
cis-diol compounds under environmental pH at or above 5.5.
The availability of this Wulff-type boronate greatly expands
the application range of boronate affinity-based approaches to
samples of medium acidic pH, such as urine and saliva.
It is noteworthy that the supporting materials are not
necessarily limited to monoliths. The new Wulff-type boronate
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c
This journal is The Royal Society of Chemistry 2011
Chem. Commun., 2011, 47, 8169–8171 8171