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【求助】AFM可以直接表征溶液样本,是吗
大家好,我合成的纳米颗粒不稳定,大慨有20min的稳定期。因此我想避免复杂的制样过程,而去直接表征样本溶液中的纳米颗粒。听说AFM可以直接表征溶液样本,是吗?谁有相关的经验可以告诉我下吗?【求助】AFM可以直接表征溶液样本,是吗
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【求助】AFM可以直接表征溶液样本,是吗
【求助】AFM可以直接表征溶液样本,是吗
字体: 小 中 大 | 打印 发表于: 2016-2-07 16:46 作者: hcy517 来源: 分析测试百科网
最新回复
p1900 (2016-2-07 16:46:34)
886爱 (2016-2-07 16:47:01)
不过测溶液难度很大,不仅仅对设备要求高,对使用者技术也要求高。
如果仅仅是为了表征一下形貌,不建议用AFM
兔子 (2016-2-07 16:47:26)
n111 (2016-2-07 16:47:48)
目前的SPM设备不少都带着个液相测试的附属功能
但是如何把图做漂亮很花时间和精力
你要找得到愿意给你做的人,你就去做吧。
mimima (2016-2-07 16:48:10)
你想知道纳米颗粒的什么性质呢?如果只是尺寸,建议用散射方法。
danzi (2016-2-07 16:48:31)
efp (2016-2-07 16:48:54)
PP熊 (2016-2-07 16:49:23)
The sample of dsDNA or ssDNA (10 μl) was deposited onto a freshly cleaved mica surface (Ted
Pella, Inc.) and left to adsorb for 10 min. Then 10 mM MOPS (12.5 mM Mg2+) (500 μl) was
added to the liquid cell and the sample was scanned in a tapping mode using Agilent AFM
series 5500 (Agilent Technologies, USA) with 0.08 N/m force constant cantilever of a Silicon
nitride cantilevers with sharpened Pyramidal tip (OMCL-TR400PSA, Olympus, Atomic Force
F&E GmbH, Mannheim, Germany). After engagement the tapping amplitude set point was
typically 2.0 volts and the scan rates ranged from 1-2 Hz. During the liquid AFM imaging the
better imaging was in most cases obtained with minimal loading forces applied and optimized
feedback parameters. Several AFM images, all 512 × 512 pixels, were obtained from separate
locations across the mica surfaces to ensure reproducibility of the results. All the images were
analyzed by using Gwyddion 2.16 software.
我看了,貌似没什么制样过程。你们帮我研究一下,难度在哪里?我打算请公司或者高校的人帮我做。
hcy517 (2016-2-07 16:49:47)
The sample of dsDNA or ssDNA (10 μl) was deposited onto a freshly cleaved mica surface (Ted
Pella, Inc.) and left to adsorb for 10 min. Then 10 mM MOPS (12.5 mM Mg2+) (500 μl) was
added to the liquid cell and the sample was scanned in a tapping mode using Agilent AFM
series 5500 (Agilent Technologies, USA) with 0.08 N/m force constant cantilever of a Silicon
nitride cantilevers with sharpened Pyramidal tip (OMCL-TR400PSA, Olympus, Atomic Force
F&E GmbH, Mannheim, Germany). After engagement the tapping amplitude set point was
typically 2.0 volts and the scan rates ranged from 1-2 Hz. During the liquid AFM imaging the
better imaging was in most cases obtained with minimal loading forces applied and optimized
feedback parameters. Several AFM images, all 512 × 512 pixels, were obtained from separate
locations across the mica surfaces to ensure reproducibility of the results. All the images were
analyzed by using Gwyddion 2.16 software.
我看了,貌似没什么制样过程。你们帮我研究一下,难度在哪里?我打算请公司或者高校的人帮我做。
QQ爱 (2016-2-07 16:50:15)
此外,能保证纳米颗粒分散均匀,尤其是在液体表面有分布,就不需要特殊制样。
efp (2016-2-07 16:50:40)
n111 (2016-2-07 16:51:07)
zouyou (2016-2-07 16:51:38)
efp (2016-2-07 16:52:06)
qinqinai (2016-2-07 16:52:30)
886爱 (2016-2-07 16:53:11)
QQ爱 (2016-2-07 16:55:07)
2)悬浮颗粒沉降吸附到基板的时间与粒径可能存在一定关系,一般说来,大颗粒会稳定得快,小颗粒相对较慢。那么,如果你的颗粒粒径不均匀,在特定时刻,基板上吸附的粒子的粒径分布会与实际溶液中粒子的粒径分布差别很大。很可能得情况是,大量的大粒径粒子,或者是杂质已经布满了基板,而你想看的5nm粒子还没有足够地出现。
如果你不关心粒径分布,只要证明有5nm的粒子,那么可以试试。但是要尽可能的除去大粒径的粒子和杂质,例如多次过滤。
3)前面说到了吸附的时间,你引的文献中是10分钟。文献中还提到了扫描参数, 512 pixel, 1-2 Hz,算下来扫一张图是4.3至8.6分钟。考虑到你要看到5nm的粒子,要实现这个分辨率,4至8分钟一张图已经很勉强了。再加上仪器操作调试的时间,即使一个非常熟练的操作者,在仪器性能和状态极好的条件下,最乐观的估算,也很难在20分钟内完成从一张图(从进样开始计时)。再考虑到你的样品吸附时间可能需要更长,你的粒子能稳定到图像扫出来么?
甚至,如果你的粒子吸附不那么牢靠的话,很有可能就被AFM的针尖推走了。
4)如果你确实想试试,建议一,处理基板,调节表面荷电性,甚至改变溶剂,目的是增强样品粒子在基板的吸附能力;二,用质量较好的针头过滤器,多次过滤溶液,除去大粒子和杂质;三,找个熟练工,找个好仪器、好针尖。
5)再次建议用散射方法。前面已经有人提到了,原理上,动态光散射能给出溶液中1纳米以下至微米级的粒径分布。不过最好找个懂散射的人做,不然光有那么台仪器,给出的数据不一定靠谱,解释起来更是容易出错。
【求助】AFM可以直接表征溶液样本,是吗