6 research outputs found
Reversible immobilization of glucose oxidase on polyaniline grafted polyacrylonitrile conductive composite membrane
WOS: 000279575300001PubMed: 20444598Polyacrylonitrile membrane surfaces were modified with chemical polymerization of conductive polyaniline. The effect of aniline concentration on the grafting efficiency was investigated As the amount of grafted PANI increased on the PAN membrane, the electrical resistance of composite membrane decreased Composite (PAN/PANI)-1-5 membrane were used for reversible immobilization of GOD. The immobilization efficiency and the activity of the immobilized GOD were increased with increasing PANI contents of the composite membrane. The maximum amount of immobilized enzyme into composite PAN/PANI-5 membrane containing 2.1% PANI was about 251 mu g/cm(2) Immobilized GOD exhibited 66% of its original activity even after two months of storage at 4 degrees C while the free enzyme lost its initial activity after three weeks (C) 2010 Elsevier Ltd. All rights reserve
Polyaniline grafted polyacylonitrile conductive composite fibers for reversible immobilization of enzymes: Stability and catalytic properties of invertase
WOS: 000267619700014Polyacylonitrile fibers (PAN) surfaces were modified with chemical polymerization of conductive polyaniline (PANI) in the presence of potassium dichromate as an oxidizing agent. The effect of aniline concentration on the grafting efficiency and on the electrical surface resistance of PAN/PANI composite fibers was investigated. The surface resistance of the conductive composite fibers in this work was found to be between 8.0 and 0.5 k Omega/cm. As the amount of grafted PANI increased on the PAN fibers the electrical resistance of composite fibers decreased. The PAN/PANI composite fibers were characterized by SEM and FTIR studies. Composite PAN/PANI fibers were used for reversible immobilization of invertase. The immobilization efficiency and the activity of the immobilized invertase (from 1.0 mg/mL invertase solution at pH 5.5) were increased with increasing PANI contents of the composite fibers. The maximum amount of immobilized enzyme onto composite fibers containing 2.0% PANI was about 76.6 mg/g. The optimum pH for the free enzyme was observed at 5.0. On the other hand, immobilized invertase yielded a broad optimum PH profile between pH 5.0 and 7.0. Immobilized invertase exhibited 83% of its original activity even after two months storage at 4 degrees C while the free enzyme showed only 7% of its initial activity. (C) 2009 Elsevier Ltd. All rights reserved
DETERMINATION OF VETERINARY DRUG RESIDUES IN SEA WATER, SEDIMENT, AND NATURAL FISH IN THE AEGEAN SEA
BAYDAN, Emine/0000-0001-5459-8616; ALTINTAS, Levent/0000-0002-5148-723X; AYDIN, FARAH GONUL/0000-0002-0068-2078; Yurdakok-Dikmen, Begum/0000-0002-0385-3602WOS: 000349805300011In this research, residues of certain veterinary drugs (florfenicol (FF) and florfenicol amine (FFA)) were screened in natural fish, sediment, and seawater samples of the Aegean Sea, while only chloramphenicol (CAP) was searched for in the sediment. Samples were collected from fish farming cages in selected coordinates (Bodrum, Salihli Region, Turkey) on September, October 2011 and March, April 2012. Method validation and analyses were carried out by HPLC method. For FF; LOD values were 25.11 ppb for sea water, 27.07 ppb for sediment as well as 38.16 and 37.95 ppb for Mullus barbatus and Oblada tnelanura fish samples. FFA value for Mullus barbatus was 39.60 ppb, respectively. For CAP in sediment samples, LOD values were found as 53.59 ppb. In 4 different sampling areas (A, B, C, D), the lowest temperature was recorded as 14 degrees C in March 2012 but the highest was 28.3 degrees C in October 2011; the lowest dissolved oxygen (mg/L) values were detected in March 2012 (from 6.05 to 6.44), the highest in October 2011(10.78-11.55). The pH values slightly varied month by month; the lowest was 7.9 and the highest 8.6. This research revealed that dissolved oxygen and pH values of the collected seawater samples were in accordance with the normal limits of the offshore seawater values; no significant residue of the analyzed veterinary drugs was found to be present, and all values were found to be lower than LOD values in the sampled fish farms. In conclusion; there was no pollution caused by veterinary drugs.General Directorate of Agricultural Research and Policy (GDAR), Ministry of Food, Agriculture and Livestock [TAGEM 10/AR-GE/20]This study was granted by General Directorate of Agricultural Research and Policy (GDAR), Ministry of Food, Agriculture and Livestock, with the project number: TAGEM 10/AR-GE/20
DETERMINATION OF VETERINARY DRUG RESIDUES IN SEA WATER, SEDIMENT, AND NATURAL FISH IN THE AEGEAN SEA
WOS: 000349805300011In this research, residues of certain veterinary drugs (florfenicol (FF) and florfenicol amine (FFA)) were screened in natural fish, sediment, and seawater samples of the Aegean Sea, while only chloramphenicol (CAP) was searched for in the sediment. Samples were collected from fish farming cages in selected coordinates (Bodrum, Salihli Region, Turkey) on September, October 2011 and March, April 2012. Method validation and analyses were carried out by HPLC method. For FF; LOD values were 25.11 ppb for sea water, 27.07 ppb for sediment as well as 38.16 and 37.95 ppb for Mullus barbatus and Oblada tnelanura fish samples. FFA value for Mullus barbatus was 39.60 ppb, respectively. For CAP in sediment samples, LOD values were found as 53.59 ppb. In 4 different sampling areas (A, B, C, D), the lowest temperature was recorded as 14 degrees C in March 2012 but the highest was 28.3 degrees C in October 2011; the lowest dissolved oxygen (mg/L) values were detected in March 2012 (from 6.05 to 6.44), the highest in October 2011(10.78-11.55). The pH values slightly varied month by month; the lowest was 7.9 and the highest 8.6. This research revealed that dissolved oxygen and pH values of the collected seawater samples were in accordance with the normal limits of the offshore seawater values; no significant residue of the analyzed veterinary drugs was found to be present, and all values were found to be lower than LOD values in the sampled fish farms. In conclusion; there was no pollution caused by veterinary drugs.General Directorate of Agricultural Research and Policy (GDAR), Ministry of Food, Agriculture and Livestock [TAGEM 10/AR-GE/20]This study was granted by General Directorate of Agricultural Research and Policy (GDAR), Ministry of Food, Agriculture and Livestock, with the project number: TAGEM 10/AR-GE/20
Rates of skincare product and cosmetic procedure use in patients with acne vulgaris and the effective factors: A multicenter study with 1,755 patients
Background Skincare products and cosmetic procedures are used as an adjunct or complementary to conventional drug therapy for acne vulgaris (AV). Objective To evaluate the use of skincare products and the frequency of cosmetic procedures in AV treatment. Methods A total of 1,755 patients with AV completed the survey prepared by the researchers and the Cardiff Acne Disability Index (CADI) questionnaire. The clinical findings and the Food and Drug Administration (FDA) severity scores were recorded by the dermatologists. Results For AV, 66.7% of the patients stated that they used skincare products and 26.7% had undergone cosmetic procedures. The use of skincare products was statistically significantly higher in women (female: 74.5%, male: 57.7%, p =%76.8, p < 0.0001). The rate of cosmetic procedures was higher in those with higher CADI scores (users: 7.8 +/- 3.8; non-users: 7.1 +/- 3.96, p < 0.0001); older patients (users: 22.7 +/- 10.7 years; non-users: 21.3 +/- 5 years, p < 0.0001); high school (25.6%); and graduate (28.9%) education (p = 0.043), those with lower disease severity (FDA-1: 31.1%; FDA-2: 28.5%, FDA-3: 27.1%, FDA-4: 20.4%, p = 0.022); smokers (smokers: 32.5%; non-smokers: 25.5%, p = 0.020), and those with AV in the family (present: 29.8%; absent: 24.2%, p = 0.009). The patients most frequently used cleansers (85.2%) as cosmetic products, and most commonly underwent skincare treatment (71%) as an interventional procedure. They mostly learned about such products and methods from the Internet, and 33.3% of the participants had undergone procedures performed by non-physicians. Conclusion The patients generally choose skincare products as a result of their Internet search and sometimes have these procedures performed by non-physicians. Dermatologists should be aware of this situation and inform their patients about appropriate products and procedures