تاریخ انتشار : پنجشنبه 27 آبان 1400 - 22:02
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کد خبر : 102358

برش باکتری‌ها با پوشش کاشت ضد میکروبی گرافیتی

برش باکتری‌ها با پوشش کاشت ضد میکروبی گرافیتی

دانشمندان دانشگاه فناوری چالمرز(Chalmers) موفق به ساخت یک پوشش نانو گرافیتی شده اند که باکتری ها را برش می دهد و منجر به نابودی آنها می شود، اما سلول های انسانی را دست نخورده باقی می گذارد. به گزارش ایسنا و به نقل از نیو اطلس، همیشه این خطر وجود دارد که وسایل پزشکی کاشته شده

برش باکتری‌ها با پوشش کاشت ضد میکروبی گرافیتی

دانشمندان دانشگاه فناوری چالمرز(Chalmers) موفق به ساخت یک پوشش نانو گرافیتی شده اند که باکتری ها را برش می دهد و منجر به نابودی آنها می شود، اما سلول های انسانی را دست نخورده باقی می گذارد.

به گزارش ایسنا و به نقل از نیو اطلس، همیشه این خطر وجود دارد که وسایل پزشکی کاشته شده در بدن(ایمپلنت) به باکتری ها آلوده شوند و باعث ایجاد عفونت ها و حتی گاهی نیاز به برداشتن آنها شود. اکنون به لطف یک پوشش نانو گرافیتی جدید، احتمال بروز چنین عوارضی بسیار کمتر می شود.

این فناوری توسط دانشمندان دانشگاه فناوری چالمرز سوئد ساخته شده است. آنها در نسخه قبلی، با استفاده از ورقه های گرافن چیزی مشابه پوشش جدید ایجاد کرده بودند. پوشش قبلی از یک ماده زیرلایه افقی تشکیل شده بود که از تکه های گرافن که به صورت عمودی بیرون زده بود، بهره می برد.

اگر یک باکتری روی سطح آن پوشش قرار می گرفت، لبه های تیز غشای بیرونی آن موجب بریده شدن باکتری و نابودی آن می شد. در نتیجه میکروب قادر به تجمع و تسخیر سطح پوشش داده شده ایمپلنت نمی شد.

با این حال یکی از مشکلات مربوط به پوشش قبلی این واقعیت است که تولید لبه های گرافنی بسیار پرهزینه است. محققان با توجه به این محدودیت به جستجوی منبعی مبتنی بر کربن ارزانتر از گرافن یعنی گرافیت پرداختند.

آنها به ساخت یک پوشش جدید متشکل از یک پایه پلی اتیلن و نانو ورقه های گرافیت پرداختند.

این نانو ورقه ها مانند همان لایه های گرافنی کار می کنند و با بریدن باکتری ها آنها را می کشند. نکته مهم این است که سلول های انسانی توسط آنها آسیب نمی بینند. این امر به این دلیل است که هر سلول حدود ۲۵ برابر بزرگتر از یک باکتری است، بنابراین این پوشش تنها خراش کوچکی بر سلول ها می اندازند.

“سانتوش پاندیت” سرپرست این مطالعه می گوید: این پوشش علاوه بر کاهش رنج بیماران و کاهش نیاز آنها به آنتی بیوتیک ها، می تواند به کاهش وسایل مراقبتی مورد نیاز و بهبودی بیماران کمک کند. زیرا ایمپلنت ها می توانند بیشتر از آنچه که امروزه استفاده می شوند در بدن باقی بمانند. تحقیقات ما همچنین می تواند با کاهش هزینه های شگرف این گونه عفونت ها باعث ایجاد خدمات درمانی بهتر در سراسر جهان شود.

این تحقیق در مجله Small منتشر شده است.

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