Cationic imidazolium polymer monoliths for efficient solvent
exchange, activation and fluorination on a continuous flow system
Rehana Ismail
1,2
, Jonathan Irribaren
1,2
, Muhammad Rashed Javed
1,2
, Ariella Machness
1,2
, R. Michael van
Dam
1,2
, Pei Yuin Keng*
1,2
1
Department of Molecular and Medical Pharmacology,
2
Crump Institute for Molecular Imaging, David
Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, U.S.A.
Supporting Information
Grafting of the glass channels of the microfluidic chip
Glass microfluidic chip was functionalized with methacryloxypropyltrimethoxysilane following a
literature report.
1
The siloxly ether groups on the glass surface was first hydrolyzed to activate the glass
surface by flowing NaOH (1 M,1 mL) through an empty microfluidic chip at 1ml/hr for 30 minutes. The
microfluidic channel was then washed with water followed by HCl (1M, 1 mL) to neutralize the residual
NaOH on the glass surface. The chip was finally washed with water (0.5 mL) and ethanol (0.5 mL). The
activated microfluidic chip was dried in a vacuum oven overnight at 80°C. The channels were then
incubated with the methacryloxypropyltrimethoxysilane (0.31 g, 1.3 mM, 0.3 mL) solution in acetone
(3:7 v/v) in dark at room temperature overnight. The excess alkoxysilane reagent was washed with
acetone and then air dried. The functionalized glass chip was kept in the dark at 2-8 °C.
0 min
30 min
45 min
Scale
150µm
Scale
150µm
Scale
150µm
Fig. S-1: Optical images of the UV-polymerization of vinylbenzylchloride and divinylbenzene within the
glass microfluidic chip at different times.
UV-photografting of the inner surface of ETFE tubing
Benzophenone (0.25 g, 1.4 mM) and EDMA (0.1 g; 0.5 mmoles; 95 µL) was dissolved in 5 mL
of acetone to achieve a final concentration of 0.1 M of ethylene dimethacrylate (EDMA) and 5% of
benzophenone in acetone according to a modified literature report.
2
The reaction mixture was sonicated
in a Schintilation vial for ~ 5 minutes. The degassed mixture was immediately charged into a 1/16 inch
OD ETFE (ID 400µm) tubing using a syringe and capped. The tubing was placed inside the UV
spectrolinker equipped with a 254 nm lamp at 504 mJ/m
2
for 20 min. After the initial photografting step,
the tubing was washed with ~ 1 mL of acetone and briefly dried with air.
The pore size of the vinylbenzyl chloride polymer monolith ranged from 1115 µm to 0.0036 µm with
while the average pore size was 0.2490 µm. The surface area of the polymer monolith was determined by
BET analysis using nitrogen gas and found to be 1.047m
2
/g.
Electronic Supplementary Material (ESI) for RSC Advances.
This journal is © The Royal Society of Chemistry 2014