熒光適配器用于環(huán)境中微塑料觀察
微塑料,塑料纖維或尺寸約為毫米或更小的顆粒,在我們周圍的中無處不在,特別是在海洋環(huán)境中。一些微塑料是主要的,故意制造得很小,以執(zhí)行特定的功能,如洗面奶和化妝品,而另一些是次要的,由較大碎片的劣化產(chǎn)生。微塑料已在多種海洋生物體內(nèi)檢出,造成不同程度的毒性效應(yīng),但由于技術(shù)限制,關(guān)于海洋魚類對小粒徑微塑料攝入和排出過程的定量研究仍比較缺乏.
伴隨人們生活節(jié)奏的加快,社會生活正向便利化、衛(wèi)生化發(fā)展。為了順應(yīng)這種需求,一次性泡沫塑料飯盒、塑料袋、筷子、水杯等開始頻繁地進(jìn)入人們的日常生活。這些使用方便、價(jià)格低廉的包裝材料的出現(xiàn)給人們的生活帶來了諸多便利。但另一方面,這些包裝材料在使用后往往被隨手丟棄,造成極大環(huán)境危害。
許多小組現(xiàn)在正在使用體視顯微鏡的熒光適配器作為微塑料工作的工具。我們從查爾斯頓學(xué)院的一個(gè)使用該系統(tǒng)的團(tuán)隊(duì)那里了解到這個(gè)應(yīng)用程序。菲爾·達(dá)斯坦博士和他的學(xué)生一直在研究各種各樣的科目,包括海洋和陸地。許多感興趣的顆粒發(fā)出熒光,并清晰地顯示在樣品中。他們甚至在鷹糞樣本中發(fā)現(xiàn)了微塑料顆粒!
鷹的糞便在體視顯微鏡下的熒光
微塑料除了進(jìn)入食品外,微塑料還可以摻入制成品中。使用熒光適配器在體視顯微鏡下看著紙巾和衛(wèi)生紙,對發(fā)光斑點(diǎn)和纖維的數(shù)量感到驚訝。
白光照射紙巾在體視顯微鏡下觀察
紙巾在450nm激發(fā)光源照射下發(fā)出熒光
白光照射衛(wèi)生紙
衛(wèi)生紙?jiān)谠?50nm激發(fā)光源照射下發(fā)出熒光
許多實(shí)驗(yàn)室開始使用450NM的藍(lán)光激發(fā)光源來觀察微塑料的熒光,這也是上面紙巾和衛(wèi)生紙樣品所顯示的。他們后來添加了紫外線激發(fā)光源,以擴(kuò)展其檢測功能。許多合成纖維在紫外激發(fā)下具有強(qiáng)烈的藍(lán)色熒光。根據(jù)我們迄今為止的經(jīng)驗(yàn),我們現(xiàn)在的建議是,對于顆粒(非纖維),是皇家藍(lán),以紫外線為備選。對于超細(xì)纖維來說,這是相反的 - 紫外線激發(fā)應(yīng)該發(fā)現(xiàn)更多熒光。
上海峰志儀器有限公司現(xiàn)貨供應(yīng)LUYOR-3420UR體視顯微鏡熒光適配器(標(biāo)配365nm和450nm),能夠滿足實(shí)驗(yàn)室利用體視顯微鏡觀察各種微塑料的熒光。
Microplastics and Fluorescence
Microplastics, plastics fibers or particles on the order of millimeters or less in size, have become ubiquitous in the world around us, and especially in the marine environment. Some of the microplastics are primary, purposely manufactured to be small to perform specific functions such as in facial cleansers and cosmetics, while others are secondary, produced by deterioration of larger pieces. A Google search on ‘microplastics in the environment’ will point you to many good references.
A number of groups are now using the NIGHTSEA Stereo Microscope Fluorescence Adapter as a tool in their work with microplastics. We learned about this application from a team at the College of Charleston that used the system. Dr. Phil Dustan and his students have been examining a wide variety of subjects, both marine and terrestrial. Many of the particles of interest fluoresce and show up clearly in samples. They even found microplastic particles in a sample of eagle poop!
The Dustan lab started out using the Royal Blue excitation/emission set, and that is also what is shown for the paper towel and toilet paper samples. They later added the Ultraviolet set to expand their detection capabilities. Many synthetic fibers have a strong blue fluorescence under ultraviolet excitation. See our article on fibers collected by a washing machine discharge filter. Our recommendation now based on our experience to date is that for particles (non-fiber), the first choice would be Royal Blue, with Ultraviolet as the backup. For microfibers this is reversed – Ultraviolet should find more with Royal Blue as a powerful backup.