1. |
- Coll, M., et al.
(author)
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Towards Oxide Electronics: a Roadmap
- 2019
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In: Applied Surface Science. - : Elsevier BV. - 0169-4332 .- 1873-5584. ; 482, s. 1-93
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Journal article (peer-reviewed)abstract
- At the end of a rush lasting over half a century, in which CMOS technology has been experiencing a constant and breathtaking increase of device speed and density, Moore’s law is approaching the insurmountable barrier given by the ultimate atomic nature of matter. A major challenge for 21st century scientists is finding novel strategies, concepts and materials for replacing silicon-based CMOS semiconductor technologies and guaranteeing a continued and steady technological progress in next decades. Among the materials classes candidate to contribute to this momentous challenge, oxide films and heterostructures are a particularly appealing hunting ground. The vastity, intended in pure chemical terms, of this class of compounds, the complexity of their correlated behaviour, and the wealth of functional properties they display, has already made these systems the subject of choice, worldwide, of a strongly networked, dynamic and interdisciplinary research community. Oxide science and technology has been the target of a wide four-year project, named Towards Oxide-Based Electronics (TO-BE), that has been recently running in Europe and has involved as participants several hundred scientists from 29 EU countries. In this review and perspective paper, published as a final deliverable of the TO-BE Action, the opportunities of oxides as future electronic materials for Information and Communication Technologies ICT and Energy are discussed. The paper is organized as a set of contributions, all selected and ordered as individual building blocks of a wider general scheme. After a brief preface by the editors and an introductory contribution, two sections follow. The first is mainly devoted to providing a perspective on the latest theoretical and experimental methods that are employed to investigate oxides and to produce oxide-based films, heterostructures and devices. In the second, all contributions are dedicated to different specific fields of applications of oxide thin films and heterostructures, in sectors as data storage and computing, optics and plasmonics, magnonics, energy conversion and harvesting, and power electronics.
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2. |
- Hellstrom, A., et al.
(author)
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New insights into the development of retinopathy of prematurity - importance of early weight gain
- 2010
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In: Acta Pædiatrica. - : Wiley. - 1651-2227 .- 0803-5253. ; 99:4, s. 502-508
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Research review (peer-reviewed)abstract
- Evidence is accumulating that one of the strongest predictors of retinopathy of prematurity (ROP), in addition to low gestational age, is poor weight gain during the first weeks of life. In infants born preterm, the retina is not fully vascularised. The more premature the child, the larger is the avascular area. In response to hypoxia, vascular endothelial growth factor (VEGF) is secreted. For appropriate VEGF-induced vessel growth, sufficient levels of insulin-like growth factor I (IGF-I) in serum are necessary. IGF-I is a peptide, related to nutrition supply, which is essential for both pre- and post-natal general growth as well as for growth of the retinal vasculature. In prematurely born infants, serum levels are closely related to gestational age and are lower in more prematurely born infants. At preterm birth the placental supply of nutrients is lost, growth factors are suddenly reduced and general as well as vascular growth slows down or ceases. In addition, the relative hyperoxia of the extra-uterine milieu, together with supplemental oxygen, causes a regression of already developed retinal vessels. Postnatal growth retardation is a major problem in very preterm infants. Both poor early weight gain and low serum levels of IGF-I during the first weeks/months of life have been found to be correlated with severity of ROP. Conclusion: This review will focus on the mechanisms leading to ROP by exploring factors responsible for poor early weight gain and abnormal vascularisation of the eye of the preterm infant.
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- Hultborn, Ragnar, 1946, et al.
(author)
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Efficacy of pamidronate in breast cancer with bone metastases: a randomized, double-blind placebo-controlled multicenter study
- 1999
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In: Anticancer Res. - 0250-7005. ; 19:4C, s. 3383-92
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Journal article (peer-reviewed)abstract
- PURPOSE: To evaluate the efficacy of pamidronate 60 mg i.v. q 4 weeks in women with advanced breast cancer with skeletal metastases. PATIENTS AND METHODS: 404 woman with skeletal metastases from breast cancer in Sweden and Norway were included in a randomized, placebo-controlled, multicenter study. Except for the study medication, other palliative treatment was chosen at the discretion of the physician. Skeletal related events, i.e. increased pain, treatment of hypercalcemia, pathologic fractures of long bones or pelvis, paralyses due to vertebral compression, palliative radiotherapy for skeletal metastases, surgery on bone and change of antitumor therapy were recorded every third month as well as a self-estimated pain-score using visual Analog Scales and analgesic consumption. RESULTS: There was a significantly increased time to progression of pain (p < 0.01), to hypercalcemic events (p < 0.05) as well as for the cumulative number of skeletal related events (p < 0.01) in favor for the pamidronate group. No statistically significant reduction of pathologic fractures of long bones or pelvis, or pareses due to vertebral compression occurred. No statistically significant differences were found for the need of radiotherapy and surgery on bone. The pamidronate group faired better regarding performance status (p < 0.05). There was a statistically not significant lower consumption of opioid analgesics in the pamidronate group (p = 0.14). CONCLUSION: Pamidronate 60 mg i.v. q 4 weeks reduces skeletal events and improves the quality of life in women with bone metastases from breast cancer.
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- Löfqvist, Chatarina, 1964, et al.
(author)
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A pharmacokinetic and dosing study of intravenous insulin-like growth factor-I and IGF-binding protein-3 complex to preterm infants
- 2009
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In: Pediatric Research. - 1530-0447 .- 0031-3998. ; 65:5, s. 574-9
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Journal article (peer-reviewed)abstract
- In preterm infants, low levels of insulin like growth factor 1 (IGF-I) have been associated with impaired growth and retinopathy of prematurity. Our objective was to study safety and pharmacokinetics of i.v. administered rhIGF-I with its binding protein 3 (rhIGFBP-3) to preterm infants. At 3 d chronological age, an i.v. 3 h infusion of rhIGF-I/rhIGFBP-3 was administered followed by serial measurements of IGF-I and IGFBP-3. Infants were evaluated for physiologic safety measurements. The individual dose of rhIGF-I ranged from 1 to 12 microg/kg. The study was conducted at Queen Silvia Children's Hospital, Gothenburg, Sweden, between January and November 2007. Five patients (3 F) with mean (range) post menstrual age 27 wk (26-29) and birth weight 1022 g (810-1310) participated. IGF-I and IGFBP-3 levels before infusion were median (range) 18 (12-28) and 771 (651-1047) ng/mL, respectively. Immediately after study drug infusion, serum IGF-I and IGFBP-3 levels were 38 (25-59) and 838 (754-1182) ng/mL, respectively. Median (range) half-life for IGF-I and IGFBP-3 was 0.79 (0.59-1.42) and 0.87 (0.85-0.94) hours, respectively. Blood glucose, insulin, sodium, potassium, and physiologic safety measures were within normal ranges. The rhIGF-I/rhIGFBP-3 equimolar proportion was effective in increasing serum IGF-I levels and administration under these study conditions was safe and well tolerated.
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5. |
- Maanja, M, et al.
(author)
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An electrocardiography score predicts heart failure hospitalization or death beyond that of cardiovascular magnetic resonance imaging
- 2022
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In: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 12:1, s. 18364-
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Journal article (peer-reviewed)abstract
- The electrocardiogram (ECG) and cardiovascular magnetic resonance imaging (CMR) provide powerful prognostic information. The aim was to determine their relative prognostic value. Patients (n = 783) undergoing CMR and 12-lead ECG with a QRS duration < 120 ms were included. Prognosis scores for one-year event-free survival from hospitalization for heart failure or death were derived using continuous ECG or CMR measures, and multivariable logistic regression, and compared. Patients (median [interquartile range] age 55 [43–64] years, 44% female) had 155 events during 5.7 [4.4–6.6] years. The ECG prognosis score included (1) frontal plane QRS-T angle, and (2) heart rate corrected QT duration (QTc) (log-rank 55). The CMR prognosis score included (1) global longitudinal strain, and (2) extracellular volume fraction (log-rank 85). The combination of positive scores for both ECG and CMR yielded the highest prognostic value (log-rank 105). Multivariable analysis showed an association with outcomes for both the ECG prognosis score (log-rank 8.4, hazard ratio [95% confidence interval] 1.29 [1.09–1.54]) and the CMR prognosis score (log-rank 47, hazard ratio 1.90 [1.58–2.28]). An ECG prognosis score predicted outcomes independently of CMR. Combining the results of ECG and CMR using both prognosis scores improved the overall prognostic performance.
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- Niklasson, Gunnar A., 1953-, et al.
(author)
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Optics of sunscreen lotions : Preliminary results on scattering and absorption coefficients
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Other publication (other academic/artistic)abstract
- Sunscreen lotions are used to protect the skin from damage due to solar ultraviolet (UV) radiation. The active UV-blocking components can be organic molecules or inorganic particles, for example TiO2. While both in-vivo and in-vitro methods exist for assessing the protective capacity of sunscreens, their basic optical properties have received little attention. In this paper we take the first steps to address this issue by presenting a method to obtain spectra of absorption and scattering coefficients of a sunscreen by analysis of experimental transmittance and reflectance spectra. We model the optical properties of the sunscreen by two-flux theory, develop approximate expressions for interface reflection coefficients and obtain the remaining optical parameters by fitting the two-flux theory to measurements. We analyze spectrophotometric reflectance and transmittance spectra of experimental narrow band UV blocking materials based on mesoporous magnesium carbonate – TiO2 mixtures, as well as some commercial sunscreens. Our method is demonstrated in vitro using quartz substrates and is further used to model in vivo measurements on the upside of the hand of one of the authors. The obtained absorption and scattering coefficient spectra give information on the relative contributions of these processes to the UV-blocking effect as well as the scattering of visible light responsible for the whitening of the skin upon application of a sunscreen lotion. Our analysis method may be useful for computational optimization of novel sunscreen formulations as well as for the development of in-vivo test methods.
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11. |
- Niklasson, Gunnar, 1953-, et al.
(author)
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Light Scattering Parameters by Inversion of Experimental Data: The Case of Sunscreen Lotions
- 2021
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In: Proceedings of the Bremen Zoom Workshop on Light Scattering 2021. - Bremen : Leibniz Institute for Materials Engineering IWT. ; , s. 16-19
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Conference paper (peer-reviewed)abstract
- We present a method to obtain absorption and backscattering coefficients of a light scattering material and apply it to the technologically important case of sunscreen lotions. While both in-vivo and in-vitro methods exist for assessing the ultraviolet (UV) protective capacity of sun-screens, their basic optical properties have previously received little attention. We model the light scattering properties by two-flux theory and invert spectrophotometric total transmittance and reflectance measurements to obtain backscattering and absorption coefficient spectra.
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- Wilkinson, S. Mark, et al.
(author)
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The European baseline series and recommended additions : 2023
- 2023
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In: Contact Dermatitis. - : Wiley. - 0105-1873 .- 1600-0536. ; 88:2, s. 87-92
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Research review (peer-reviewed)abstract
- The European baseline series was last updated in 2019. This article discusses the reasoning behind a further iteration of the series for 2023.
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15. |
- Albers, E, et al.
(author)
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Continuous estimation of product concentration with calorimetry and gas analysis during anaerobic fermentations of Saccharomyces cerevisiae
- 2002
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In: Thermochimica Acta. - 0040-6031. ; 394:1-2, s. 185-190
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Journal article (peer-reviewed)abstract
- Product concentrations may be estimated from gas analysis or calorimetric measurements. These techniques of analysis are fast, simple, and provide a continuous output. To check the accuracy of these estimations, the anaerobic ethanol formation of an industrial strain of the yeast Saccharomyces cerevisiae was selected as a test system. Cultivations were carried out as batch cultures with different nitrogen sources (ammonium, glutamate and a mixture of amino acids) and 20 g/l of glucose as the carbon and energy source. The results showed that there was a good agreement between measured and calculated ethanol values. However, especially when using heat data the results are very sensitive to small changes in the stoichiometry of the catabolic reaction, i.e. ethanol is not the only product but there are also minor amounts of glycerol and acetate. The problems generated by these products when using heat data to calculate ethanol concentrations are discussed in detail. (C) 2002 Elsevier Science B.V. All rights reserved.
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19. |
- Bayrak Pehlivan, I., et al.
(author)
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A polymer electrolyte with high luminous transmittance and low solar throughput : Polyethyleneimine-lithium bis(trifluoromethylsulfonyl) imide with In2O3:Sn nanocrystals
- 2012
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In: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 100:24, s. 241902-
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Journal article (peer-reviewed)abstract
- Chemically prepared similar to 13-nm-diameter nanocrystals of In2O3:Sn were included in a polyethyleneiminelithium bis(trifluoromethylsulfonyl) imide electrolyte and yielded high haze-free luminous transmittance and strong near-infrared absorption without deteriorated ionic conductivity. The optical properties could be reconciled with effective medium theory, representing the In2O3:Sn as a free electron plasma with tin ions screened according to the random phase approximation corrected for electron exchange. This type of polymer electrolyte is of large interest for opto-ionic devices such as laminated electrochromic smart windows.
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26. |
- Costenoble, R, et al.
(author)
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Engineering of the metabolism of Saccharomyces cerevisiae for anaerobic production of mannitol
- 2003
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In: FEMS Yeast Research. - 1567-1364. ; 3:1, s. 17-25
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Journal article (peer-reviewed)abstract
- Under anaerobic conditions, Saccharomyces cerevisiae uses NADH-dependent glycerol-3-phosphate dehydrogenase (Gpd1p and Gpd2p) to re-oxidize excess NADH, yielding substantial amounts of glycerol. In a Δgpd1 Δgpd2 double-null mutant, the necessary NAD+ regeneration through glycerol production is no longer possible, and this mutant does not grow under anaerobic conditions. The excess NADH formed can potentially be used to drive other NADH-dependent reactions or pathways. To investigate this possibility, a double-null mutant was transformed with a heterologous gene (mtlD) from Escherichia coli, coding for NADH-dependent mannitol-1-phosphate dehydrogenase. Expression of this gene in S. cerevisiae should result in NADH oxidation by the NADH-requiring formation of mannitol-1-phosphate from fructose-6-phosphate. The strain was characterized using step-change experiments, in which, during the exponential growth phase, the inlet gas was changed from air to nitrogen. It was found that the mutant produced mannitol only under anaerobic conditions. However, anaerobic growth was not regained, which was probably due to the excessive accumulation of mannitol in the cells.
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27. |
- Costenoble, R, et al.
(author)
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Microaerobic glycerol formation in Saccharomyces cerevisiae.
- 2000
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In: Yeast (Chichester, England). - 0749-503X. ; 16, s. 1483-95
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Journal article (peer-reviewed)abstract
- The yeast Saccharomyces cerevisiae produces large amounts of glycerol as an osmoregulator during hyperosmotic stress and as a redox sink at low oxygen availability. NAD(+)-dependent glycerol-3-phosphate dehydrogenase in S. cerevisiae is present in two isoforms, coded for by two different genes, GPD1 and GPD2. Mutants for either one or both of these genes were investigated under carefully controlled static and dynamic conditions in continuous cultures at low oxygen transfer rates. Our results show that S. cerevisiae controls the production of glycerol in response to hypoxic conditions by regulating the expression of several genes. At high demand for NADH reoxidation, a strong induction was seen not only of the GPD2 gene, but also of GPP1, encoding one of the molecular forms of glycerol-3-phosphatase. Induction of the GPP1 gene appears to play a decisive role at elevated growth rates. At low demand for NADH reoxidation via glycerol formation, the GPD1, GPD2, GPP1, and GPP2 genes were all expressed at basal levels. The dynamics of the gene induction and the glycerol formation at low demand for NADH reoxidation point to an important role of the Gpd1p; deletion of the GPD1 gene strongly altered the expression patterns of the GPD2 and GPP1 genes under such conditions. Furthermore, our results indicate that GCY1 and DAK1, tentatively encoding glycerol dehydrogenase and dihydroxyacetone kinase, respectively, may be involved in the redox regulation of S. cerevisiae.
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- Gonzalez-Borrero, P. P., et al.
(author)
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Optical band-gap determination of nanostructured WO3 film
- 2010
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In: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 96:6
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Journal article (peer-reviewed)abstract
- The optical band-gap energy of a nanostructured tungsten trioxide film is determined using the photoacoustic spectroscopy method under continuous light excitation. The mechanism of the photoacoustic signal generation is discussed. The band-gap energy is also computed by other methods. The absorption coefficient as well as the band-gap energy of three different crystal structures of tungsten trioxide is calculated by a first-principles Green's function approach using the projector augmented wave method. The theoretical study indicates that the cubic crystal structure shows good agreement with the experimental data.
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35. |
- Granqvist, Claes Göran, et al.
(author)
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Electrochromic foil-based devices : Optical transmittance and modulation range, effect of ultravioled irradiation, and quality assessment by 1/f current noise
- 2008
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In: Thin Solid Films. - : Elsevier BV. - 0040-6090 .- 1879-2731. ; 516:17, s. 5921-5926
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Journal article (peer-reviewed)abstract
- We introduce electrochromic (EC) technology for modulating the transmittance of visible light and solar radiation in window apertures, with focus on recent work on foil-type devices embodying sputter deposited WO3 and NiO films joined by a polymer electrolyte. The purpose of this paper is to present a number of new and preliminary results showing that (i) double-sided antireflection coatings based on dip coating can enhance the transmittance significantly, (ii) tandem foils can yield a ratio between bleached-state and colored-state transmittance exceeding fifty, (iii) solar irradiance onto the EC device can enhance its charge insertion dynamics and thereby its optical modulation, and (iv) electromagnetic noise spectroscopy may serve as quality assessment of EC devices.
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- Hammar, M. L., et al.
(author)
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Effects of hormonal replacement therapy on the postural balance among postmenopausal women
- 1996
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In: Obstetrics and Gynecology. - 0029-7844 .- 1873-233X. ; 88:6, s. 955-960
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Journal article (peer-reviewed)abstract
- OBJECTIVE: To establish whether hormone replacement therapy affects postural balance in postmenopausal women. METHODS: Nineteen healthy postmenopausal women with vasomotor symptoms were included. Median age was 54 years, median time since menopause was 3 years. They underwent dynamic posturography before and after 4 and 12 weeks of transdermal estrogen treatment (17 beta-estradiol 50 micrograms/day) as well as after 2 additional weeks of combined estrogen-progestagen treatment. The dynamic posturography method quantifies the amplitude, frequency, and pattern of body sway and tests the visual, vestibular, and somatosensory systems, which together maintain balance. The two most difficult tests either cancel visual and distort somatosensory inputs or give distorted information from both the visual and somatosensory systems. RESULTS: Hormone replacement therapy increased static balance performance assessed by dynamic posturography. A highly significant improvement was seen in the two most difficult tests between the pretreatment test and the test performed after 4 weeks of estrogen therapy (P < .01, P < .001, respectively). This improvement was sustained after 12 weeks and also during the 14th week, with the women on combined estrogen-progestagen treatment. CONCLUSION: Estrogen treatment increased balance performance measured by dynamic posturography, indicating that the beneficial effects from estrogens on postmenopausal fracture risk may include central nervous system effects on balance. Two weeks' addition of gestagen to the treatment regimen did not counteract the estrogen effects.
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39. |
- Harmini, Sri, et al.
(author)
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Fungal Pretreatment of Oil Palm Empty Fruit Bunch : Effect of Manganese and Nitrogen
- 2013
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In: Cellulose Chemistry and Technology. - : Editura Academiei Romane. - 0576-9787. ; 47:9-10, s. 751-757
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Journal article (peer-reviewed)abstract
- Oil palm empty fruit bunch (OPEFB) was biologically pretreated using Pleurotus floridanus LIPIMC996 supplemented with various concentrations of manganese and nitrogen and incubated for 35 days at 30°C, and enzyme activities of manganese peroxidase (MnP) and laccase were examined. When OPEFB was supplemented with manganese, the highest lignin reduction was achieved up to 25.0±5.6% at the addition of 200 μg Mn2+/g OPEFB.In addition, Pleurotus floridanus LIPIMC996 grew best on OPEFB supplemented with 800 μg Mn2+/g OPEFB. When OPEFB was supplemented with nitrogen, the highest lignin reduction was achieved up to 27.2± 3.5% at the addition of 20 mM nitrogen. The best growth of Pleurotus floridanus was also achieved with the addition of 20 mM nitrogen. The addition of nitrogen and manganese on OPEFB did not significantly affect the activity of MnP and laccase.
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40. |
- Harmini, S, et al.
(author)
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Fungal Pretreatment of Oil Palm Empty Fruit Bunch: Effect of Manganese and Nitrogen
- 2013
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In: Cellulose Chemistry and Technology. - 0576-9787. ; 47:9-10, s. 751-757
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Journal article (peer-reviewed)abstract
- Oil palm empty fruit bunch (OPEFB) was biologicallypretreated usingPleurotus floridanusLIPIMC996 supplementedwith various concentrations of manganese and nitrogen and incubated for 35 days at 30°C, and enzyme activities ofmanganese peroxidase (MnP) and laccase were examined. When OPEFB was supplemented with manganese, thehighest lignin reduction was achieved up to 25.0±5.6% at the addition of 200 μg Mn2+/g OPEFB.In addition,PleurotusfloridanusLIPIMC996 grew best on OPEFB supplemented with 800μg Mn2+/g OPEFB. When OPEFB wassupplemented with nitrogen, the highest lignin reduction was achieved up to 27.2± 3.5% at the additionof 20 mMnitrogen. The best growth ofPleurotus floridanuswas also achieved with the addition of 20 mM nitrogen. The additionof nitrogen and manganese on OPEFB did not significantly affect the activity of MnP and laccase.
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41. |
- Hellström, Ann, 1959, et al.
(author)
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Early weight gain predicts retinopathy in preterm infants: new, simple, efficient approach to screening
- 2009
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In: Pediatrics. - 1098-4275. ; 123:4, s. 638-645
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Journal article (peer-reviewed)abstract
- BACKGROUND: The risk for sight-threatening retinopathy of prematurity is predicted by using gestational age and/or weight at birth. All infants below a threshold undergo serial ophthalmologic examinations for identification of those who would benefit from treatment (approximately 10%). We hypothesized that factoring in postnatal weight gain could identify children at risk for sight-threatening retinopathy of prematurity more specifically and earlier. METHODS: Weekly weights from birth to postmenstrual week 36 were retrospectively entered into a surveillance system that gave an alarm when the rate of weight gain decreased to a certain level. For all children (N = 354) screened and/or treated for retinopathy of prematurity at Sahlgrenska University Hospital in 2004-2007, weekly weights were recorded. One child was excluded because of known nonphysiologic weight gain (hydrocephalus). RESULTS: For 127 (36%) of 353 children, no alarm was given; for 40%, alarm at low risk was given after postmenstrual week 32. None of those children developed retinopathy of prematurity requiring treatment. Of the remaining 24% of children who received alarm at high or low risk before 32 postmenstrual weeks, 41% developed proliferative retinopathy of prematurity and 29% were treated because of sight-threatening disease. The median time from alarm to treatment was 9 weeks. CONCLUSIONS: The weight, insulin-like growth factor, neonatal retinopathy of prematurity algorithm detected early 100% of infants who developed retinopathy of prematurity requiring treatment and correctly predicted the majority who did not require treatment. With this simple postnatal evaluation, costly stressful eye examinations can be markedly reduced (approximately 75% of infants). In addition, early identification of children at risk may lead to the initiation of interventions and possibly prevent sight-threatening retinopathy of prematurity.
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- Karlsson, Isabella, et al.
(author)
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Nature-Derived Epoxy Resin Monomers with Reduced Sensitizing Capacity-Isosorbide-Based Bis-Epoxides
- 2023
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In: Chemical Research in Toxicology. - : American Chemical Society (ACS). - 0893-228X .- 1520-5010. ; 36:2, s. 281-290
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Journal article (peer-reviewed)abstract
- Epoxy resin systems (ERSs) are a class of thermosetting resins that become thermostable and insoluble polymers upon curing. They are widely used as components of protective surfaces, adhesives, and paints and in the manufacturing of composites in the plastics industry. The diglycidyl ether of bisphenol A (DGEBA) is used in 75-90% of ERSs and is thus by far the most used epoxy resin monomer (ERM). Unfortunately, DGEBA is a strong skin sensitizer and it is one of the most common causes of occupational contact dermatitis. Furthermore, DGEBA is synthesized from bisphenol A (BPA), which is a petroleum-derived chemical with endocrine-disruptive properties. In this work, we have used isosorbide, a renewable and nontoxic sugar-based material, as an alternative to BPA in the design of ERMs. Three different bisepoxide isosorbide derivatives were synthesized: the diglycidyl ether of isosorbide (1) and two novel isosorbide-based bis-epoxides containing either a benzoic ester (2) or a benzyl ether linkage (3). Assessment of the in vivo sensitizing potency of the isosorbide bis-epoxides in the murine local lymph node assay (LLNA) showed that all three compounds were significantly less sensitizing than DGEBA, especially 2 which was nonsensitizing up to 25% w/v. The peptide reactivity showed the same order of reactivity as the LLNA, i.e., 2 being the least reactive, followed by 3 and then 1, which displayed similar peptide reactivity as DGEBA. Skin permeation of 2 and 3 was compared to DGEBA using ex vivo pig skin and static Franz cells. The preliminary investigations of the technical properties of the polymers formed from 1-3 were promising. Although further investigations of the technical properties are needed, all isosorbide bis-epoxides have the potential to be less sensitizing renewable replacements of DGEBA, especially 2 that had the lowest sensitizing potency in vivo as well as the lowest peptide reactivity.
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