Surface Modification of Polystyrene by Gamma-Radiation

Onyiriuka, Emmanuel C.; Hersh, L. S.; Hertl, W.

doi:10.1366/0003702904086975

Cited by 55 publications

(26 citation statements)

References 8 publications

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“…7a and b. The only noticeable difference between irradiation in vacuum and in oxygen is the presence of a broad absorption band peaking near 1730 cm À1 , which is due to the formation of carbonyl groups (C]O), for the latter environment, similar to that reported for normal PS [34]. Using the styrene aromatic band at 1500 cm À1 as a reference, it can be seen that the intensity of the 1730 cm À1 band increases with increasing dose.…”

Section: Chemical and Morphological Behaviors Of Isothermally Crystalsupporting

confidence: 65%

Melting and chemical behaviors of isothermally crystallized gamma-irradiated syndiotactic polystyrene

Liu

Nguyen

Yang

et al. 2009

Polymer

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Section: Chemical and Morphological Behaviors Of Isothermally Crystalsupporting

confidence: 65%

Melting and chemical behaviors of isothermally crystallized gamma-irradiated syndiotactic polystyrene

Liu

Nguyen

Yang

et al. 2009

Polymer

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“…In the latter case, the gamma irradiation is known to initiate radical formation and in the presence of air to lead to the incorporation of 10-20% of surface oxygen. The oxidized polystyrene surface contains numerous reactive groups, including ␣, ␤-unsaturated carbonyl groups (41), which likely form adducts with the ␤ 2 GP1 (15,40). In addition, investigators have reported that some aPLs bind to various coagulation factors, such as prothrombin (42), and again it is interesting that in some cases these antibodies may be directed at PL-bound prothrombin (43).…”

Section: Discussionmentioning

confidence: 99%

The epitopes for some antiphospholipid antibodies are adducts of oxidized phospholipid and β₂glycoprotein 1 (and other proteins)

Hörkkö

Miller

et al. 1997

Proc. Natl. Acad. Sci. U.S.A.

133

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Circulating autoantibodies to phospholipids (aPLs), such as cardiolipin (CL), are found in patients with antiphospholipid antibody syndrome (APS). We recently demonstrated that many aPLs bound to CL only after it had been oxidized (OxCL), but not to a reduced CL analogue that could not undergo oxidation. We now show that the neoepitopes recognized by some aPLs consist of adducts formed between breakdown products of oxidized phospholipid and associated proteins, such as ␤ 2 glycoprotein 1 (␤ 2 GP1). Addition of human ␤ 2 GP1, polylysine, native low-density lipoprotein, or apolipoprotein AI to OxCL-coated wells increased the anticardiolipin antibody (aCL) binding from APS sera that first had been diluted so that no aCL binding to OxCL could be detected. No increase in aCL binding was observed when these proteins were added to wells coated with reduced CL. The ability of ␤ 2 GP1, polylysine, or low-density lipoprotein to be a ''cofactor'' for aCL binding to OxCL was greatly reduced when the proteins were methylated. Incubation of ␤ 2 GP1 with oxidized 1-palmitoyl-2-linoleyl-[1-14 C]-phosphatidylcholine (PC), but not with dipalmitoyl-[1-14 C]-PC, led to formation of covalent adducts with ␤ 2 GP1 recognized by APS sera. These data suggest that the reactive groups of OxCL, such as aldehydes generated during the decomposition of oxidized polyunsaturated fatty acids, form covalent adducts with ␤ 2 GP1 (and other proteins) and that these are epitopes for aCLs. Knowledge that the epitopes recognized by many aPLs are adducts of oxidized phospholipid and associated proteins, including ␤ 2 GP1, may give new insights into the pathogenic events underlying the clinical manifestations of APS.

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“…UV irradiation and X-ray irradiation lead to opening of the polystyrene aromatic ring and comparatively much higher oxygen incorporation into the surface. Whereas the corona profile decreases linearly with depth, the UV profile exhibits a dramatic increase with depth and the gamma profile shows a relatively flat oxidation level over [1][2][3][4][5][6][7][8][9][10] nm sampling depth.…”

Section: Discussionmentioning

confidence: 99%

The effects of high‐energy radiation on the surface chemistry of polystyrene: A mechanistic study

Onyiriuka

1993

J of Applied Polymer Sci

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SYNOPSISIrradiation of polystyrene by 15 Mrad gamma or exposure to a 254 nm ultraviolet (UV) light source leads t o surface oxidation of the polymer to depths greater than 10 nm as opposed to -3 nm depth offered by either plasma or corona-discharge treatment. Oxidation increases linearly with UV irradiation time. More carboxyl (0 = C -0) acid functionality, which increases with depth, was detected for UV-treated polymer. With 3 Mrad gamma irradiation, only hydroxyl (C -0) groups were detected by XPS as the surface-oxidized species. ADXPS, GPC, and static SIMS data suggest that chain scission is the dominant degradation mechanism for polystyrene exposed to high gamma and UV radiation, respectively. 0 1993 John Wiley & Sons, Inc. INTRODUCTIONPolymer surfaces are modified to improve the surface properties such as surface energy and chemistry, while maintaining the bulk properties of the polymer. These properties are usually necessary to improve ( a ) adhesion, e.g., between fiberlresin interface; ( b ) biocompatibility; ( c ) printability; and ( d ) wettability of surfaces for tissue culture applications. The high-energy processes used for the modification of polymer surfaces include corona-discharge, lowpressure O2 plasma, and ultraviolet radiation.The reactions between a polymer surface and corona discharge are believed to proceed by a freeradical mechanism via a peroxide intermediate. oxides, carbonyls, epoxys, carboxylic acids, and esters. In applications such as label adhesion, cell adhesion, chemical coupling, etc., the extent of crosslinking or chain scission due to the treatment may be of equal importance to product performance as are the relative distribution and quantity of oxidized functional groups on the polymer surface. Failure to consider short-chain soluble species resulting perhaps from extensive chain scission could have adverse effects on the adhesion and/or mechanical properties ( e.g., hardness, tensile strength, fracture stress) of the surfaces. Therefore, it is important to evaluate the degree of cross-linking and/or chain scission due to the treatment of polymers by the various high-energy processes. Angle-dependent X-ray photoelectron spectroscopy ( ADXPS ) is a surface-sensitive technique for nondestructive depth profiles (< 10 nm thickness) of polymers. Therefore, ADXPS should be particularly sensitive to changes in the types, concentration, and depth distribution of the surface functional groups. Static secondary ion mass spectrometry (SIMS) can provide structural or long-range information about surface species; hence, it is complementary to XPS.In this work, ADXPS, size exclusion chromatography, formally known as gel permeation chromatography (GPC ), infrared spectroscopy, and static SIMS were used to study the effect of high energy 2187 2188 ONYIRIUKA ( corona-discharge, oxygen plasma, ultraviolet, Xray radiation, and gamma) treatments on polystyrene. EXPERIMENTAL Material TreatmentsThe surfaces studied were commercial injectionmolded polystyrene dishes and roller bottles (except film...

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Surface Modification of Polystyrene by Gamma-Radiation

Cited by 55 publications

References 8 publications

Melting and chemical behaviors of isothermally crystallized gamma-irradiated syndiotactic polystyrene

Melting and chemical behaviors of isothermally crystallized gamma-irradiated syndiotactic polystyrene

The epitopes for some antiphospholipid antibodies are adducts of oxidized phospholipid and β₂glycoprotein 1 (and other proteins)

The effects of high‐energy radiation on the surface chemistry of polystyrene: A mechanistic study

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Surface Modification of Polystyrene by Gamma-Radiation

Cited by 55 publications

References 8 publications

Melting and chemical behaviors of isothermally crystallized gamma-irradiated syndiotactic polystyrene

Melting and chemical behaviors of isothermally crystallized gamma-irradiated syndiotactic polystyrene

The epitopes for some antiphospholipid antibodies are adducts of oxidized phospholipid and β2glycoprotein 1 (and other proteins)

The effects of high‐energy radiation on the surface chemistry of polystyrene: A mechanistic study

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The epitopes for some antiphospholipid antibodies are adducts of oxidized phospholipid and β₂glycoprotein 1 (and other proteins)