Transcript #625 Surface Analysis of Resin

Degradation of an Organic Overlayer Model of a Dental Composite
Analyzed by Liquid Chromatography Mass Spectrometry
Peter Koin,2 Ayben Kilislioglu,4 Manshui Zhou,1 James L. Drummond,3 and Luke Hanley1,*
University of Illinois at Chicago, Departments of 1Chemistry, 2Bioengineering, and 3Restorative Dentistry, m/c 111, Chicago, IL 60607-7061 USA
4Istanbul University, Department of Chemistry, Avcilar 34320, Istanbul, Turkey
Experimental Methods
Degradation Study Purpose
31.6% H2O2
Nanoporous silicon
1.0
50°C, 1hr
20 mA/cm2, 5 min
Porous SiO2 Surface (Stored in 1N HNO3 Solution)
Porous SiO2
60°C, 96hrs
96
HO
O
88
Wash
Toluene
80°C, 12hrs
80
72
0.6
0.5
0.4
64
56
576
Initiator Solution
747
64
56
48
40
32
708
48
532
752
40
24
488
0.3
2.0 mg/ml BisGMA/EtOH
72
Unknown Structure
88
0.7
Baking
16
32
Cure, UV light
0.2
796
24
20 min
161
87
840
444
8
16
0.1
4
6
8
10
12
14
16
18
Retention T ime (min)
20
22
24
26
28
30
80
Instrumentation
• TIC of Extract from Methacryoyl BisGMA monolayer on nanoporous
silicon aged for 2 weeks in DI water.
•LCMS
–Finnigan Mat LcQ
•HPLC
–SpectraSYSTEMS SCM 1000 vacuum membrane degasser
–P4000 gradient elution pump
–AS 3000 autosampler
–UV 2000 dual-wave length detector
Si
O
O
Si
O
O
O
OH
O
OH
O
MPS
Methacryloyl overlayer
SiO2 Surface
+
OH
O
O
Si
O
O
O
O
hv
OH
O
O
OH
Eosin Y / TEA / VP
O
O
O
Bis-GMA
HO
OH
O
O
O
O
Bis-GMA-methacryloyl overlayer
Relative Intensity (%)
0.7
0.6
0.1
536
684
Goals
•Study degradation of Dental Composite Model after aging in
water for 2 weeks
•Qualitative analysis to find degradation peaks using MS
Fragmenter software and MS-MS analysis
800
880
0
5
560
640
720
800
O
HO
Unknown Structure
CH3
HO
B
OH
O
O
OH
CH3
O
O
590
CH3
678
O
H3C
A
O
CH3
O
OH
64
CH2
722
56
48
CH 3
766
546
HO
O
H 2C
40
CH 3
HO
O
CH 3
OH
O
810
O
502
24
O
HO
O
458
16
10
15
20
Retention T ime (min)
25
30
35
CH 3
H 3C
H 3C
80
160
240
320
400
480
560
640
720
800
880
•Electrospray ion trap mass spectra of (BisGMA)”’ Polymer at 21.8
min, which is a BisGMA polymer derivative with a m/z difference of
44 between peaks.
CH 3
BisGMA-2MA
m/z 363
BisGMA-MA
m/z 462
40
96
Retention Time
(min)
m/z
Name
# of
runs
Method of ID peak
Structure
(# of runs)
Structure
556
CH 3
H 2C
O
88
H 2C
O
HO
530
BisGMA
26
HO
O
530
HO
CH 3
H 2C
O
HO
O
72
88
O
HO
CH 3
O
Unknown Structure
80
O
HO
CH 3
H 3C
O
O
64
MS of StandardObvious
CH 3
H 3C
O
O
O
O
O
O
O
H 2C
20.623 +/- 0.517
634
(BisGMA)”
25
Unknown Structure
MS/MS (14)
19.088 +/- 0.477
620
(BisGMA)’
15
Unknown Structure
MS/MS (4)
21.819 +/- 0.526
644
(BisGMA)”’
12
Unknown Structure
MS/MS (8)
72
CH 3
H 3C
56
48
CH 3
H 2C
O
CH 3
H 2C
HO
O
O
O
64
56
600
48
644
669
688
512
40
O
32
O
CH 3
468
32
11.343 +/- 0.547
CH 3
H 3C
24
462
BisGMA-MA
O
H 2C
HO
O
15
462
HO
O
732
16
Standards
•Resin Material: BisGMA
•Silane Coupler: MPS- not run because of adverse effect of
MPS with columns
•Photoinitiator solution: triethanolamine, vinyl
pyrrolidinone, and eosin Y
•Glass Filler: nanoporous silicon chip, prepared similar to
DIOS chips
16.014 +/- 0.546
96
CH 3
+
NH4
O
80
CH 3
H 2C
CH 3
H 2C
40
880
HO
•Electrospray ion trap mass spectra of BISGMA from TIC at 16.0
min with a main peak of m/z 530.
Standards Analysis to find retention time
3 nanoporous silicon chips per sample
2 weeks aged in de-ionized water
Also aged blank nanoporous silicon chip with no BisGMA or
methacryloyl layer to determine nanoporous silicon background
480
BisGMA-methacryloyl monolayer
m/z
•Mobile Phase: Gradient of MeOH/H20
•Flow Rate: 0.3 ml/min
•Temperature: Room Temperature, 25°C
•UV Wavelength: 250 nm
•Column: Reverse Phase Water Symmetry C18 3.5 μm, 3.0 mm
diameter, 150 mm length
•Injection volume: 10 μL
Aged Monolayer Samples
400
•Reaction of BisGMA-methacryloyl monolayer in the presence of
water. Hydrolysis of ester bonds causes degradation products of
BisGMA to appear. Hydrolysis reactions can also occur at black
arrows, but do not show up in sample data.
8
16
513
495
8
424
H 3C
80
160
240
320
400
480
560
640
720
800
880
80
160
240
320
400
480
m/z
96
H2C
O
494
HO
H 2C
HO
O
H 2C
192
277
HO
O
72
H 3C
H 2C
O
CH 3
CH 3
428
HO
O
HO
O
CH 3
O
O
48
C
C
H 3C
40
O
HO
O
495
CH3
H3C
OH
56
O
O
O
+
80
CH 3
CH3
O
H3C
+
HO
+
O
CH3
M+NH4
CH 3
H 3C
OH
H 2C
O
O
HO
O
CH 3
H2C
5
HO
CH 3
363
O
O
H 3C
H 2C
88
O
64
880
O
O
O
72
800
CH3
CH3
O
720
Electrospray ion trap mass spectra from TIC at RT= 11.5 min with a
main peak at m/z 462 that corresponds to a BisGMA degradation
product
462
CH3
80
640
363
BisGMA2MA
MS Fragmenter
Software
CH 3
Conclusions
96
H2C
CH 3
MS Fragmenter
Software, MSMS
(4)
HO
CH 3
m/z
• MSMS of BisGMA, m/z 530. Spectra shows the M+NH4 peak
at m/z 530, M+H peak at m/z 513, M-H20+H at m/z 495, and
main degradation products at m/z 191, 277, and 427513
88
560
OH
O
776
8
24.115 +/- 0.304
CH 3
O
64
H 3C
56
CH3
CH 3
O
48
H 2C
HO
O
•Unreacted BisGMA strongly adsorbs to surface of
nanoporous silicon and slowly leaches out
•Aging also causes hydrolysis of ester bonds and
causes degradation products of BisGMA to appear
•Oligomer peaks with unknown structures also
appear after aging
OH
40
O
32
HO
32
O
+H
24
24
H 3C
16
530
8
277
191
150
200
250
300
409
350
400
8
450
500
550
CH 3
16
427
323
m/z
[1] MS Zhou, JL. Drummond, L Hanley. Dental Materials. 21 (2005) : 145-155.
[2] MS. Zhou, CP. Wu, PD. Edirisinghe, JL. Drummond, L. Hanley. Journal of
Biomedical Materials Research A. 76 (2006).
720
32
29.484
462
0.2
20.443
Data Analysis Software
ACD Labs (Toronto, Ont., Canada)
•ACD MS Manager to analyze and process data
•ACD MS Fragmenter- Program generates fragments and
structures by using standard fragmentation rules
18.568
0.3
634
363
23.746
620
610
33.199
21.779
645
31.317
0.5
0.4
–Possible Degradation Products: bisphenol A,
methacrylic acid
320
72
24
O
640
Si
80
OH
O
560
0.8
Relative Intensity (%)
O
480
88
Relative Intensity (%)
+
400
96
0.9
Relative Intensity (%)
OH
O
320
634
1.0
HPLC Conditions
OH
O
240
•Electrospray ion trap mass spectra of (BisGMA)” Polymer at 20.4 min.
530
Relative Intensity (%)
OH
160
m/z
530
Dental Composite Model
240
m/z
15.973
•Dental composites made of resin matrix, glass particle filler, and a
silane coupling agent
•Resin matrix: Bisphenol A glycerolate dimethacrylate
(BisGMA)
•Glass filler: Nanoporous silicon chip
•Silane coupling agent: MPS- 3- (trimethoxysilyl) propyl
methacrylate
•Glass particles used to reduce overall polymer shrinkage
•Silane coupler covalently links resin to glass filler: improves
mechanical properties and increases hydrolytic stability due to
hydrophobic nature
2
11.535
Monolayer System
0
Relative Intensity
•Degradation studies of commercial composites too complex [1]
•Monolayer system to understand degradation and erosion [2]
160
8
Polymerized methacryloyl BisGMA Overlayer
CH 3
H 3C
80
New System of Analysis
CH 3
O
96
0.8
MPS-Silanized Substrate
MPS-Silanized Substrate
HO
CH 3
80
0.9
2 (wt) % MPS/Toluene
363
620
Relative Intensity (%)
•Composites undergo property changes due to oral environment
•Environment can weaken materials and reduce restoration
longevity
•Can release compounds into tissues and accumulate
•Study materials that can leach out of composite
Silicon Wafer
(N-Type 100)
• TIC of Pure BisGMA run through HPLC, no aging.
Relative Intensity
•Dental Composites consist of a polymerizable resin matrix,
reinforcing glass filler particles, and a silane coupler.
•One of the most used resin monomer of dental composites is
Bisphenol A glycerolate dimethacrylate (BisGMA)
24 (wt)% HF/EtOH
• Electrospray ion trap mass spectra of (BisGMA)’ Polymer at 18.6
min, which is a BisGMA polymer derivative with a m/z difference of
44 between peaks.
Relative Intensity (%)
Motivation
Electrospray ion trap mass spectra of BisGMA degradation product
with a m/z 363, at a retention time of 23.8 min.
Results
600
+H-H2O
150
80
160
240
320
445
427
400
480
560
640
720
800
880
m/z
Funded by National Institute of Dental and Craniofacial Research,
DE-07979