EMDT_European Medical Device Technology

European Medical Device Technology, Spring 2014

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emdt.co.uk European Medical Device Technology Spring 2014 | 51 Furthermore, some compounds, such as the plasticizer Bis(2-ethylhexyl)-phthalate (DEHP) may interact with hormone recep- tors at the surface of biological cells and induce hormone-like signals after hav- ing leached out from medical polymers. Although DEHP is not a hormone, it is called an "exogeneous hormone" or "endo- crine disruptor" due to its hormone-like capacity. According to the EU, DEHP meets the criteria for classification as toxic for reproduction (category 1B) in accord- ance with regulation (EC) Nr. 1272/2008 and should not be present in medical devices applied to adolescents and breast- feeding women, among others 6 . Leachables may also occur during the natural ageing process of polymers. This is a further argument in support of an expi- ration date for medical devices. Scientists from the U.S. Centers for Disease Con- trol and Prevention (CDC), for instance, reported in 2000 7 that a severe and unu- sual outbreak of serious neurological signs and symptoms occurred in five out of seven patients associated with the use of 10-year- old dialyzers. All patients exposed to these filters developed acute onset of diminished vision and hearing; four patients never recovered. The authors attributed these findings to material degradation of the cellulose- acetate polymer, as the average molecular weight decreased from 40,000 to 30,000 in the dialyzers tested and referred to either deacetylation (saponification) or chain scis- sion of the polymer 7 . To the surprise of many medical device manufacturers, quality management EPflex Feinwerktechnik GmbH · 72581 Dettingen/Erms · Germany Im Schwoellbogen 24 · Phone +49 (0) 71 23 / 97 84-0 Fax +49 (0) 71 23 / 97 84-22 · E-Mail: info @ epflex.com www.epflex.com Nitinol baskets Dispenser Special Guide wires Guide wires Tipless baskets Hypotubes MRI Guide wires for medical applications We create flexible solutions Table 1: Blood, composed of plasma and cells: A perfect medium for extraction Plasma (> 1300 compounds) Cells 1. Proteins (8%) among others: - albumin (50%) - immunoglobulins (antibodies, 35%) - fibrinogen (5%) 1. Erythrocytes (red blood cells, 4-5 x 1012/L) 2. Water 2. Thrombocytes (platelets, 150 - 380 x 109/L) 3. Inorganic salts; electrolytes 3. Leukocytes (white blood cells, 6-8 x 109/L) (T-cells, B-cells, macrophages, monocytes, killer-cells) 4. Further compounds hormones, fat, carbohydrates enzymes Visit us at MEDTEC Europe Stand 7A05 Visit us at MEDTEC Europe Stand 7D04 ES433895_EMDT1405_051.pgs 05.02.2014 14:04 UBM black yellow magenta cyan

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