Introduction Microplastics are becoming a major global environmental issue. Regular, newsworthy research reveals that plastics and microplastics exist in remote locations or as contaminants in different consumer products (especially food and beverages) and in marine digestive systems. The source of microplastics may be nascent microplastics, ie secondary microplastics that are specifically designed or fabricated into small sizes, or that start with larger materials but break down into smaller pieces in the environment. Initially, microplastics were defined as plastic materials having a size of less than 5 mm , but although not yet globally accepted, this definition is now more generally expressed as plastic particles having dimensions ranging from 1 mm to as small as micron. A large amount of plastic pollution in the environment is a visible and significant problem that needs to be resolved. Small-sized micro-plastics are not visible to the human eye, but they have a major impact on the health of aquatic and marine species and may eventually enter the human food chain. Analysis of environmental samples containing microplastics is critical to determining their prevalence and its effects. A range of analytical techniques have been applied to the analysis of microplastics. Among the techniques employed, infrared ( IR ) spectroscopy, and more specifically infrared microscopy, is the primary analytical technique for detecting and identifying microplastics. Micro-plastic analysis operation flow of infrared microscope There are several steps from the original sample to the final result, including sample collection to data analysis. The steps involved may vary, depending on the type of sample and the amount of sample purge required to prepare the sample by infrared ( IR ) analysis. The workflow is shown in Table 1 . Samples from different sources and different types of samples require analysis of their microplastic content. Different samples have their own complexity in terms of collection and purification. For example, the analysis of micro-plastics in bottled water does not require sample cleanup, but can be analyzed with a simple filter. The micro-plastics ingested by sewage or animals take several days to purify the samples and digest other organic materials to perform a “clean†analysis of the micro-plastics. Sample Collection The following is a brief overview of the sampling strategies taken for samples from different sources. Water sampling streams, rivers to lakes, distant seas and many other different water environments contain micro-plastics. In addition, it is reported that water from water treatment plants also contains microplastics. There are similarities between sampling requirements, as it is important to collect all the microplastics in the desired particle size range and to understand the volume of the water sample. Using a consistent sampling strategy, it is possible to determine whether the amount and / or quality of microplastics increases or decreases over time. Sample collection has different requirements for seawater and freshwater, mainly because of the different water densities. Most synthetic polymeric materials have a lower density than seawater, which means that microplastics generally float on the surface of the water, but many polymeric materials are sunk in freshwater systems. A typical device for collecting seawater surface samples is a Manta trawl of known mesh sizes that are towed behind the ship. For samples at the water level, a suitable plankton collection network is used. This method also applies to lakes and water bays. Mesh size is an important parameter because too small a mesh can cause the net to be blocked quite quickly during sample collection. The volume and area of ​​sample collection can be determined by using a flow meter and depending on the inlet size of the mesh and the distance traveled during the acquisition. To test river water, the net is usually suspended at a fixed point in the river, and the position of the net can be set or adjusted to capture at a fixed depth on the water or below the surface. Sediment sampling In many cases, (micro)plastics can be observed on the surface of a sediment sample, such as on a beach or river bank. In this case, the sample can be easily extracted and cleaned prior to analysis. However, microplastics are present at deeper levels of the deposit, so a sampling strategy is required. Sediments of known mass or volume are typically collected and the mass or amount of particles per unit volume is determined. Sediment samples can be collected from seabeds, lakes or riverbeds, or collected from beaches or river banks when the tides or rivers are lowered. The sediment sample requires further sample cleanup to extract the microplastic for analysis, which is described below. Plastic sampling of animal intake It is reported that plastics and microplastics are found in the stomachs of a variety of seabirds and marine life and often cause death. A larger plastic material can be physically extracted from the anatomy of the organism, which needs to be cleaned prior to analysis. To determine the total amount of plastic, including microplastics, it is necessary to completely remove the biomaterial by digestion prior to analysis. The various methods of digestion are discussed below. The digestion process leaves plastic material and is expected to remove all other materials. Household goods and consumer goods sampling Several microplastics are released into the drainage system in the home. It is well known that washing machines produce thousands of fibers during the cleaning process. 2 In addition, although the use of plastic microbeads is being phased out according to legislation in different countries and regions, many consumer goods and cosmetics (such as toothpaste and shower gel) contain plastic microbeads. Sampling of microplastics from household goods can be accomplished by installing a screen of suitable mesh size on the water outlet of the washing machine or the water outlet of the drainage system. In the case of exfoliating agents and body scrubs, most of their ingredients are water soluble, so mixing the sample with boiling water prior to filtration usually removes everything except microplastics. 3 Related instruments: Spotlight 400/400N FT-IR Infrared Spectral Imaging System Spectrum Two FT-IR Infrared Spectrometer For details, click the button below to request information. 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