Name: Multimodal Analysis of Microplastics in Drinking Water using a Silicon Nanomembrane Analysis Pipeline (Video) | JoVE Journal
Uploaded: 2025-06-13T13:30:00.000+00:00
Duration: 9 min 10 s
Description: Learn the Silicon Nanomembrane Analysis Pipeline for multimodal microplastics detection in drinking water. This protocol reduces contamination while enabling optical, electron, and spectroscopic imaging techniques.

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Peng Miao at Horiba Scientific generously supported this publication with the use and expertise of their XploRA Plus Raman spectroscopy system. Electron microscopy imaging was performed in the Integrated Nanosystems Center (URnano) at the University of Rochester. Microfabrication was carried out at the Semiconductor and Micro-systems Fabrication Laboratory (SMFL) at the Rochester Institute of Technology.
Research reported in this publication was supported in part by the National Institute of Environmental Health Sciences under Award No. R44ES031036 to SiMPore, and by the Lake Ontario MicroPlastics Center (LOMP) under National Institute of Environmental Health Sciences Award No. P01 ES035526 and the National Science Foundation Award No. OCE-2418255 to the University of Rochester. The content is solely the responsibility of the authors and does not necessarily represent the official views of any funding agency.

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<li>Schwabl, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Detection+of+various+microplastics+in+human+stool%5BTitle%5D)+AND+%22Ann+Intern+Med%22%5BJournal%5D)">Detection of various microplastics in human stool.</a> Ann Intern Med. 171 (7), 453-457 (2019).</li>
<li>Leslie, H. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Discovery+and+quantification+of+plastic+particle+pollution+in+human+blood%5BTitle%5D)+AND+%22Environ+Int%22%5BJournal%5D)">Discovery and quantification of plastic particle pollution in human blood.</a> Environ Int. 163, 107199(2022).</li>
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<li>Nutrition and Food Safety (NFS), Standards & Scientific Advice on Food Nutrition (SSA). Dietary and inhalation exposure to nano-and microplastic particles and potential implications for human health. , 
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<li>Fries, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Identification+of+polymer+types+and+additives+in+marine+microplastic+particles+using+pyrolysis-GC%2FMC+and+scanning+electron+microscopy%5BTitle%5D)+AND+%22Environ+Sci%3A+Processes+Impacts%22%5BJournal%5D)">Identification of polymer types and additives in marine microplastic particles using pyrolysis-GC/MC and scanning electron microscopy.</a> Environ Sci: Processes Impacts. 15 (10), 1949-1956 (2013).</li>
<li>Primpke, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Critical+assessment+of+analytical+methods+for+the+harmonized+and+cost-efficient+analysis+of+microplastics%5BTitle%5D)+AND+%22Appl+Spectrosc%22%5BJournal%5D)">Critical assessment of analytical methods for the harmonized and cost-efficient analysis of microplastics.</a> Appl Spectrosc. 74 (9), 1012-1047 (2020).</li>
<li>Carter, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Comparative+evaluation+of+filtration+and+imaging+properties+of+analytical+filters+for+microplastic+capture+and+analysis%5BTitle%5D)+AND+%22Chemosphere%22%5BJournal%5D)">Comparative evaluation of filtration and imaging properties of analytical filters for microplastic capture and analysis.</a> Chemosphere. 332, 138811(2023).</li>
<li>Van Mourik, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((STOTEN%27s+minimum+requirements+for+measurement+of+plastics+in+environmental+samples%5BTitle%5D)+AND+%22Sci+Total+Environ%22%5BJournal%5D)">STOTEN's minimum requirements for measurement of plastics in environmental samples.</a> Sci Total Environ. 912, 168465(2024).</li>
<li>Käppler, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Analysis+of+environmental+microplastics+by+vibrational+microspectroscopy%3A+FTIR%2C+Raman+or+both%5BTitle%5D)+AND+%22Anal+Bioanal+Chem%22%5BJournal%5D)">Analysis of environmental microplastics by vibrational microspectroscopy: FTIR, Raman or both.</a> Anal Bioanal Chem. 408, 8377-8391 (2016).</li>
<li>Mikoliunaite, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+substrate+matters+in+the+Raman+spectroscopy+analysis+of+cells%5BTitle%5D)+AND+%22Sci+Rep%22%5BJournal%5D)">The substrate matters in the Raman spectroscopy analysis of cells.</a> Sci Rep. 5 (1), 13150(2015).</li>
<li>Madejski, G. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Silicon+nanomembrane+filtration+and+imaging+for+the+evaluation+of+microplastic+entrainment+along+a+municipal+water+delivery+route%5BTitle%5D)+AND+%22Sustainability%22%5BJournal%5D)">Silicon nanomembrane filtration and imaging for the evaluation of microplastic entrainment along a municipal water delivery route.</a> Sustainability. 12 (24), 10655(2020).</li>
<li>Romanick, S. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Assessment+of+household+settled+dust+via+silicon+nanomembrane+analysis+pipeline+%28SNAP%29%5BTitle%5D)+AND+%22Environ+Technol+Innov%22%5BJournal%5D)">Assessment of household settled dust via silicon nanomembrane analysis pipeline (SNAP).</a> Environ Technol Innov. 38, 104106(2024).</li>
<li>Cowger, W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Microplastic+spectral+classification+needs+an+open+source+community%3A+Open+specy+to+the+rescue%5BTitle%5D)+AND+%22Anal+Chem%22%5BJournal%5D)">Microplastic spectral classification needs an open source community: Open specy to the rescue.</a> Anal Chem. 93 (21), 7543-7548 (2021).</li>
<li>Kooi, M., Koelmans, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Simplifying+microplastic+via+continuous+probability+distributions+for+size%2C+shape%2C+and+density%5BTitle%5D)+AND+%22Env+Sci+Technol+Lett%22%5BJournal%5D)">Simplifying microplastic via continuous probability distributions for size, shape, and density.</a> Env Sci Technol Lett. 6 (9), 511-564 (2019).</li>
<li><a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=%22SpectraBase%22">SpectraBase</a>. , John Wiley & Sons, Inc. SpectraBase. https://spectrabase.com/spectrum/1uoQJ4M5hxj (2025).</li>
<li>Erni-Cassola, G., Gibson, M. I., Thompson, R. C., Christie-Oleza, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Lost+but+found+with+nile+red%3A+A+novel+method+for+detecting+and+quantifying+small+microplastics+%281+mm+to+20+%C2%B5m%29+in+environmental+samples%5BTitle%5D)+AND+%22Environ+Sci+Technol%22%5BJournal%5D)">Lost but found with nile red: A novel method for detecting and quantifying small microplastics (1 mm to 20 µm) in environmental samples.</a> Environ Sci Technol. 51 (23), 13641-13648 (2017).</li>
<li>Shim, W. J., Song, Y. K., Hong, S. H., Jang, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Identification+and+quantification+of+microplastics+using+Nile+Red+staining%5BTitle%5D)+AND+%22Mar+Pollut+Bull%22%5BJournal%5D)">Identification and quantification of microplastics using Nile Red staining.</a> Mar Pollut Bull. 113 (1-2), 469-476 (2016).</li>
<li>Greenspan, P., Mayer, E. P., Fowler, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Nile+red%3A+A+selective+fluorescent+stain+for+intracellular+lipid+droplets%5BTitle%5D)+AND+%22J+Cell+Biol%22%5BJournal%5D)">Nile red: A selective fluorescent stain for intracellular lipid droplets.</a> J Cell Biol. 100 (3), 965-973 (1985).</li>
<li>Cai, B., Andino, F. D. J., Mcgrath, J. L., Romanick, S. S., Robert, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Ingestion+of+polyethylene+terephthalate+microplastic+water+contaminants+by+Xenopus+laevis+tadpoles+negatively+affects+their+resistance+to+ranavirus+infection+and+antiviral+immunity%5BTitle%5D)+AND+%22Environ+Pollut%22%5BJournal%5D)">Ingestion of polyethylene terephthalate microplastic water contaminants by Xenopus laevis tadpoles negatively affects their resistance to ranavirus infection and antiviral immunity.</a> Environ Pollut. 356, 124340(2024).</li>
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JR and JM are founders and stockholders of SiMPore Inc. JR is co-inventor on a patent application enabling the use of Silicon Nitride filters like those depicted in this study.

Microplastic pollution mitigation is a growing subject of concern; and the first step of mitigation is to identify the presence of contamination. A streamlined method of capture and immediate analysis is crucial to saving investigators time and preserving sensitive sample metrics. This report describes flexible workflows based on variations of our developed SNAP methods for the analysis of such MPs in liquid samples, utilizing a single substrate for all analyses conducted. The sample must be vacuum filtered such that the particles are captured and isolated onto a Silicon nanomembrane housed inside a filter disk. Sufficient mitigation of background contamination is critical for meaningful results. Any contaminating particles on the dispensing syringe or glass vacuum funnel during filtration may contaminate the sample and be concurrently captured, so following the Section 1 quality control protocols diligently is crucial for accurate outcomes. Media-only controls are recommended to inform investigators of background contamination specific to individual processes and laboratory conditions. The protocol described herein relies on vacuum filtration of a liquid sample, as well as capturing and isolating particles from the sample on two different cut-off SiN filter disks. For all pipelines, particle capture and isolation must precede other methods, but all other identification methods can be done in the order most suitable for the investigator.
Two fluorescent microscopes were utilized for this study to demonstrate repeatability of results across instruments. Instructional steps specifically detail the use of an Olympus BX61 for fluorescent microscopy due to the predominance of its use and was operated per instrument instructions utilizing brightfield for grayscale imaging, TRITC channel (Ex. ~543 nm; Em. ~593 nm) for NR-stained particle imaging, and Cy5 channel (Ex. ~649 nm; Em. ~667 nm) for TB-stained particle imaging, as applicable. To display the results of the staining, we recommend constructing an overlay of the channel images (we use FIJI/ImageJ for image processing, subsequently referred to as the image analysis platform), at a resolution of 2,048 x 2,040 pixels and a 16-bit depth. Whole nanomembrane images can be displayed as in Figure 4A,B or as selected regions of interest as shown in Figure 3A,B.
Nile Red is commonly used to stain synthetic polymer MPs but can stain non-synthetic polymers from biological sources due to its lipophilic and hydrophobic nature, potentially introducing false positives that distort MP quantification results24,25,26. A Trypan Blue counterstaining step, as outlined in protocol section 3, is recommended to aid in the differentiation of false-positive events but is not an exhaustive solution and should be paired with additional analysis metrics to confirm results. Nile Red fluorescence of particles is a concern with Raman spectroscopy analysis as it may significantly increase the background signal. In this study, however, we counterstained polymers with Nile Red and Trypan Blue prior to Raman spectroscopy with an 830 nm laser, and little noise was observed, as shown in Figure 3.
Some wavelengths of lasers suitable for Raman spectroscopy are not able to ignore fluorescence from stained particles, such as a 532 nm laser, and therefore may introduce significant difficulty in correctly estimating the composition of the particle of interest. Metal coating the particles after capture is useful for enhancing the contrast during SEM imaging but is incompatible with any subsequent spectroscopic or fluorescent analysis. Make a note of all desired measurements prior to experimental setup to ensure that the process flow and coating types are taken properly into account. The Au-SiN filter disks can be utilized for all the mentioned analyses where transmission microscopy is not crucial to the workflow, or when Raman or IR spectroscopy is used.
The methods shown here, as well as the nanomembranes used to capture and isolate particles of interest, can be modified to suit individual investigators&#39; needs. The nanomembranes are suitable for a number of spectroscopic analyses, and the investigator may swap the media being filtered for another sample media of interest, including but not limited to digested animal tissues27, injectable pharmaceuticals, and oil samples. Two Raman spectroscopy instruments were utilized for this study, and instructional steps specifically detail the use of a Horiba XploRA Plus Raman instrument, which collected and processed all the data shown in Figure 4. It is also important to acknowledge the size limit of detection for each Raman microscope, to ensure the particles of interest can be suitably analyzed with the spot size of the instrument&#39;s lasers. To display particle identification results with Raman, the reference and sample spectra, plus an image of the analyzed particle, can be shown as in Figure 3C and Figure&#160;4C.
Protocol section 6 details instructions for particle identification using an open-source spectral library. The planarized capture of particles onto a uniformly flat membrane, as well as the membrane&#39;s regular array of pores, enables predictable, automated imaging. Both the 400 nm or 1,000 nm thicknesses of the SiN and their Silicon nitride composition endow them with excellent optical transparency but may also return an intense Silicon peak in some spectroscopic instrument parameters. Care should be taken when utilizing bare, non-metal-coated SiN with Raman analysis. The Si peak may function as a calibration signal, but the intensity of the peak may also mask the signals of lower-intensity spectra in the same wavenumber region as the Si&#39;s signal. Such Si peaks were not observed when using the 830 nm laser in this study.
The ultrathin nature of the SiN (400 nm- or 1,000 nm-thick) and Au-SiN (520 nm- or 1,120-nm thick) used here endowed them with their excellent filtration, optical, and spectroscopic properties. However, these membranes must be protected from physical damage, such as by excessive differential pressure (i.e., &#8805;-206 kPa), direct touching by tweezers or fingers, or by improper gasket placement. The filter disk housing the membranes protects them and enables ease of handling under normal usage. When manipulating the filter disks, touch only the black outer ring, and never the active membrane area. Although not quantitatively reported here, the collection of captured particles onto a small amount of membrane surface area (3 x 3 mm for 20 &#181;m and 3 x 0.7 x 3 mm for 8.0 &#181;m cut-off membranes, respectively) potentially lowers total sample analysis time, by reducing the time needed to find and analyze particles of interest. This &#34;concentration factor&#34; is worthy of future exploration and may offer a unique benefit of SiN filter disks for investigators. In combination with their higher surface area-normalized flow rates versus other widely used membranes for MP characterization15, automated particle imaging routines that need only image a relatively smaller area of uniformly flat and in-focus SiN may further reduce total analysis times. However, any benefits related to the hypothesized concentration factor still need to be empirically demonstrated by comparing total processing times (from filtration to image analysis) on conventional and SiN filter disks.
We heuristically demonstrated the utility of the SNAP variations on local tap water samples. The protocol described here focuses on MP capture from drinking water sources around Rochester, NY. Sample collection proceeded as follows: for each sample collection, at least one liter of water was run through the faucet before collection started. New, sealed polypropylene bottles were taken to the running faucet and opened directly before collection. Bottles were not rinsed with drinking water before collection proceeded. Each sample consisted of two 500 mL bottles collected, one directly after the other. Each water sample came from a distinct household&#39;s pipe system, and the pipe material was not consistent throughout the sampling. Variables like the amount of recent water usage, time of collection, age of pipes, and the age of the home from which the sample came could not be controlled in this study. This was not a validated sample collection protocol. Each investigator should develop and validate their own collection procedures. However, for the sake of complete disclosure of methods, the above description is included. The filter disks allow repeated analysis on the same substrate for a number of analytical methods. No subsampling or multiple samples are needed outside of standard trial replicates. Eliminating the need for subsampling and multiple samples increases confidence in capturing information on low abundance targets. In addition to the enabling of multi-modal analysis methods, the SiN filter disks provide a distinct advantage over other analogous filtration medias due to the time-saving quality of a faster filtration rate per unit area15.

Microplastics are defined as synthetic polymers measuring smaller than five millimeters in size1,2. Microplastic (MP) pollution is a growing human health, environmental, and ecological concern. MP contamination has been found in water sources of all types; freshwater, oceans, and even drinking water sources3. MPs are generated from the breakdown of primary plastic sources4, as well as synthetic textiles5,6,7. MPs are ubiquitous and have been found in human tissues, such as human placenta, feces, and blood8,9,10. There is an increasing interest in MP research, as evidenced by more than 4,100 and 4,600 publications in 2023 and 2024, respectively (PubMed data; keyword &#34;microplastics&#34;), as well as an increasing public concern regarding human exposure to MPs. Responding to a growing public concern, several government regulatory bodies such as the State of California11 and several EU countries12, have been (or will be) implementing regulations on MP levels in drinking water. Considering all of the above, the US&#160;Environmental Protection Agency has recently announced MPs as a new contaminant of concern. However, human risk evaluation is severely impeded by a lack of methods for the reliable and reproducible detection of MPs.
Characterization of MPs relies on analytical methods such as optical and electron microscopy13, and spectroscopic and spectrometric techniques1,14,15 to understand the visual characteristics of MPs7 and their composition, respectively. Samples containing MPs should include multiple analyses to characterize, identify, and quantify MPs, and at least require spectroscopy/spectrometry (i.e., Raman spectroscopy, infrared spectroscopy, or pyrolysis gas chromatography-mass spectrometry, etc.) as per some journal minimal requirements for the measurement of plastics in environmental samples, such as Science of the Total Environment16. Raman spectroscopy is more versatile than infrared (IR) spectroscopy, especially with respect to material identification in biological samples. Raman spectroscopy is a light scattering technique, enabling it to analyze smaller particles more easily than IR, a light-absorbing technique that necessitates larger particles and has more constraints on sample placement17. It has been previously suggested that substrates for Raman spectroscopy comprising Silicon or Silicon oxide can yield reliable results with minimal background noise18.
Substrates for certain analytical techniques that are usually compatible with one type of analysis (i.e., Gold-coated substrates required for IR spectroscopy) are not often compatible with transmission and/or reflectance light microscopy. Subsequently, replicate subsampling is popular among investigators to produce samples appropriate for each separate analysis, but subsampling is time-consuming and could exclude low-abundance particulates1,2,6. Typically, manual transfers of particulates from one substrate to the next is necessary to analyze the same particle for characterization and identification by different analytical modalities, but these slow, manual transfers increase the likelihood of bias, contamination, and loss, as well as limit analysis of MPs to only the largest sized particles that can be manually manipulated13. These suboptimal workflows introduce numerous challenges and reliability issues, contributing to the significant variability in MP quantification reported in the literature3,7.
Here, we present an analytical workflow we call the Silicon Nanomembrane Analysis Pipeline (SNAP) to capture, characterize, identify, and quantify MPs, and demonstrate the utility of SNAP by analyzing drinking water samples sourced from the Rochester, NY region. SNAP is enabled by conventionally sized 25 mm diameter filter disks with integrated Silicon nanomembranes (See Supplemental Table S1 for membrane properties), which offer a uniform substrate for concentrating and analyzing MPs from drinking water using multiple techniques15,19. After sequentially concentrating and capturing MPs onto nanomembranes with decreasing cut-off sizes (20 &#181;m microporous Silicon nitride (MPSN) with cylindrical pores and 8.0 &#181;m microslit Silicon nitride (MSSN) with rectangular prism pores), SNAP facilitates three consecutive analytical steps: 1) sample staining, optical microscopy, and MP quantification, 2) particle identification via Raman spectroscopy, followed by 3) particle characterization via scanning electron microscopy (SEM), enabling multiple analyses of the same particles captured onto one nanomembrane substrate.
We demonstrate multiple SNAP pipelines by utilizing both uncoated Silicon nanomembrane (SiN) filter disks and Gold coated Silicon nanomembrane (Au-SiN) filter disks: Pipeline A) SNAP performed on SiN and sequentially characterizing the same MPs through multiple analytical techniques; Pipeline B) SNAP performed on Au-SiN with Raman spectroscopy; and Pipeline C) SNAP performed on Au-SiN with SEM equipped with energy dispersive X-ray spectroscopy (EDX) (Figure 1). SNAP variations are thus flexible, streamlined analytical workflows that can be used for a number of sample types and analytical techniques. Unlike previously published methods that rely on polymeric membranes11, SNAP&#39;s advantages derive from its use of Silicon nanomembranes, where synthetic polymer MPs are captured onto a non-polymeric, Silicon-based membrane, enabling the compositional identification of MPs on a non-polymeric background. Further, Silicon nanomembranes offer uniform focal planes unlike polymeric membranes, which tend to wrinkle, enabling multiple automated microscopy and spectroscopy techniques.
We previously characterized the use of Silicon nanomembranes for MP analyses by analytical modeling, model particle challenges, and drinking water and air samples19,20, as well as by comparing their filtration and optical microscopy properties using model particles against four widely used membranes15. In this protocol, we heuristically demonstrate SNAP&#39;s utility for the analysis of MPs in four drinking water samples. Samples were collected from four distinct water sources around the greater Rochester, NY area. Each sample included in this study originated from a distinct surface water source, such as Lake Ontario, Hemlock Lake, a mix of Hemlock and Ontario, and Canandaigua Lake (Figure 2). Captured particles from these drinking water sources included widespread plastics like polystyrene (PS) and polyethylene (PE), heavy metals like iron, silica, and non-synthetic particles.

<table><tbody><tr><td>1 L Glass beaker</td><td>Pyrex</td><td>1000-1L</td><td></td></tr><tr><td>1 L Glass vacuum collection flask</td><td>Millipore Sigma</td><td>Z290459-1EA</td><td></td></tr><tr><td>100% cotton lab coat</td><td>Landau</td><td>LA-3172</td><td></td></tr><tr><td>100 mL glass filtration funnel&amp;nbsp;</td><td>Advantec</td><td>311000</td><td>https://www.sterlitech.com/glass-filter-holder-311000.html</td></tr><tr><td>99% isopropyl alcohol</td><td>Fisher Scientific</td><td>A416-20</td><td></td></tr><tr><td>APEX EDS</td><td>EDAX</td><td></td><td>EDX software used to perform EDX analysis on captured particles.&amp;nbsp;</td></tr><tr><td>Denton Prep Sputtering System</td><td>Denton Vacuum</td><td>DESK II : 293618089</td><td>Gold coating system</td></tr><tr><td>FIJI, image analysis platform</td><td>ImageJ</td><td>V 1.54F</td><td>FIJI (FIJI is just ImageJ) - a distribution of ImageJ&amp;nbsp;</td></tr><tr><td>Glass screw-cap bottle</td><td>Corning&amp;nbsp;</td><td>1395-250</td><td></td></tr><tr><td>Kimwipes</td><td>Kimtech</td><td>06-666-11C</td><td></td></tr><tr><td>LabSpec6</td><td>Horiba Scientific</td><td></td><td>Horiba Raman software containing ParticleFinder and ViewSharp</td></tr><tr><td>Laminar flow hood</td><td>Air Science</td><td>VLF-72A</td><td></td></tr><tr><td>Microscope&amp;nbsp;</td><td>Olympus&amp;nbsp; / Nikon</td><td>BX61 / Ti2e</td><td>Any microscope with suitable fluorescence can be utilized for optical microscopy.&amp;nbsp;</td></tr><tr><td>MPSN SiN filters</td><td>SiMPore Inc.</td><td>FD25-8.0-Au; FD25-8.0-NC&lt;br/&gt; FD25-20.0-Au, FD25-20.0-NC</td><td></td></tr><tr><td>Monoject 60 mL syringes</td><td>Coviden</td><td>8881560265</td><td></td></tr><tr><td>Nile Red powder</td><td>TCI</td><td>N0659</td><td></td></tr><tr><td>Nitrile Gloves</td><td>Ansell Microflex</td><td>19-167-17</td><td></td></tr><tr><td>OpenSpecy</td><td>openanalysis.org</td><td></td><td>Open source, spectral library</td></tr><tr><td>Oven</td><td>VWR</td><td>1310</td><td>Gravity Convection Utility Oven</td></tr><tr><td>P20 Pipette</td><td>Brandtech</td><td>705872</td><td></td></tr><tr><td>Pipette tip</td><td>Premium Vials</td><td>GS 151140R</td><td></td></tr><tr><td>Pourous support frit</td><td>Advantec</td><td>311000</td><td>Part of bundle</td></tr><tr><td>Raman instrument</td><td>Horiba</td><td>Xplora PLUS</td><td></td></tr><tr><td>Rubber stopper</td><td>Advantec</td><td>311000</td><td>Part of bundle</td></tr><tr><td>SEM instrument</td><td>Ziess</td><td>Auriga</td><td>Auriga Series, Modular Crossbeam workstation</td></tr><tr><td>Silicone gaskets</td><td>SiMPore</td><td>GASKET-25-R</td><td>Clear-cast PDMS gaskets, 0.8 mm thick</td></tr><tr><td>Silicone Roller</td><td>Sanyue</td><td>&amp;nbsp;(ASIN: B07XDTNPS3)</td><td>Silicone roller -&amp;nbsp; 8 x 5 x 2 inches</td></tr><tr><td>SmartSEM</td><td>Zeiss</td><td>V8</td><td>SEM software used to operate the Zeiss Auriga</td></tr><tr><td>Spray bottle</td><td>Uline</td><td>S-7273</td><td></td></tr><tr><td>Syringe filters&amp;nbsp;</td><td>Thermo Scientific</td><td>CH2225-PES</td><td>0.22 &amp;micro;m luer lock syringe filters, 25 mm&amp;nbsp;</td></tr><tr><td>Syringe pump</td><td>New Era Pump Systems, Inc.</td><td>NE-1000</td><td>Optional, but reccomended</td></tr><tr><td>Trypan Blue - 0.4%</td><td>Millipore Sigma</td><td>T8154-20ML</td><td></td></tr><tr><td>Tweezers</td><td>SiMPore</td><td>K6TWZR</td><td></td></tr><tr><td>Vacuum pump</td><td>Welch</td><td>847-676-8800</td><td></td></tr><tr><td>Vacuum tubing</td><td>Grainger</td><td>ZUSA-HT-4037</td><td></td></tr></tbody></table>

multimodal analysis of microplastics in drinking water using a silicon nanomembrane analysis pipeline

Multimodal Analysis of Microplastics in Drinking Water using a Silicon Nanomembrane Analysis Pipeline

The biological impact of microplastic pollution in human food and water sources is largely unknown, and drinking water sources are not exempt from this microplastic contamination. Here, we demonstrate a streamlined approach for capturing, quantifying, and identifying microplastics in drinking water. We present an analytical workflow termed the Silicon Nanomembrane Analysis Pipeline (SNAP) that takes advantage of novel Silicon nitride nanomembranes that enable a significant "concentration factor," which consolidates suspended particles into a planarized observation area for individuated, quantifiable, and multimodal particle analysis on the same substrate. SNAP's primary advantages derive from its use of ultrathin, Silicon nitride-based membranes housed in conventionally sized filter disks, enabling the direct capture and analysis of polymeric MPs on a non-polymeric background. Drinking water samples sourced in the Rochester, NY region, were collected from residential tap sources and analyzed using SNAP. Particles in each sample were characterized by optical and scanning electron microscopy (SEM), Raman spectroscopy, and energy-dispersive X-ray spectroscopy (EDX), and various identified constituents were quantified in proportion to the total captured particles.

Here, we present a protocol showcasing an optically transparent and flat substrate for the streamlined capture and analysis of contaminating particles in drinking water. Presented here is the Silicon Nanomembrane Analysis Pipeline (SNAP): a flexible pipeline for the capture, quantification, and identification of particles in liquid media.

The biological impact of microplastic pollution in human food and water sources is largely unknown, and drinking water sources are not exempt from this ...

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Research

JoVE Journal

Environment

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Sampling and Identification of Microplastics in Groundwater

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EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. I. Collection of Virus Samples

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EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. Part III. Virus Detection by RT-qPCR

Learn the Silicon Nanomembrane Analysis Pipeline for multimodal microplastics detection in drinking water. This protocol reduces contamination while enabling optical, electron, and spectroscopic imaging techniques.

Multimodal Analysis of Microplastics in Drinking Water using a Silicon Nanomembrane Analysis Pipeline

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