Table 4 Adsorption pathways of nanoplastics
Chemical–physical characteristics | Type of nanoplastics | Type of study | Absorption pathways | Ref. |
|---|---|---|---|---|
Gold-core polystyrene, 25 nm, uniform spherical, hydrophilic by photooxidation during synthesis | Virgin | In vitro, microfluidic on-chip (IOC) model | Absorption by epithelial cells of the IOC model via receptor-mediated endocytosis tested through inhibitors of endocytic mechanisms | |
Polystyrene, 50, 100 and 500 nm, spherical, negative charge, hydrophilic by surface modification | Virgin | In vivo (mice) | Observation of nanoplastics in intestinal sections; no investigation of the mechanism of overcoming intestinal barriers and uptake | |
Polystyrene, 50, 500 and 5,000 nm, spherical, positive charge, hydrophilic | Virgin | In vivo (mice) | Observation of nanoplastics in intestinal sections; co-exposure increases absorption for damage to the intestinal barrier; no investigation of the mechanism of overcoming intestinal barriers and uptake | |
Polystyrene, 60 nm, spherical | Virgin | In vivo (mice, only female) | Endocytosis by M cells in Peyer’s plates with absorption and translocation from the intestinal lumen and mucus layer | |
Polystyrene, 80 nm, spherical, negative charge, aggregation tendency | Virgin | In vitro, exposure to IEC-6 cell line | Observation of nanoplastics in lysosomes of IEC-6 cells before aggregation; no investigation of the absorption mechanism | |
In vivo (mice, only male) | Observation of an intracellular effect (dysfunctional mitophagy with weakening of the intestinal barrier) | |||
Polymethylmethacrylate, 25 nm, spherical, negative charged, hydrophilic | Virgin | In vitro, exposure to Caco-2 cell line | No observation of nanoplastics inside and outside the cell membrane; observation of transport through the mucus layer model | |
Polylactic acid 250 nm, spherical, negative charge | Cellular uptake (potential clathrin-mediated endocytosis) and transport through the simulated monolayer by HT29-MTX and Caco-2 cell lines (<10%) | |||
Melamine formaldehyde resin, 366 nm, spherical, positive charge, hydrophilic | Cellular uptake (potential endocytosis mediated by caveolin or macropinocytosis) and transport through the simulated monolayer by HT29-MTX and Caco-2 cell lines (<10%) | |||
Polylactic acid 2 μm, spherical, negative charge | Cellular uptake (potential macropinocytosis) and transport through the simulated monolayer by HT29-MTX and Caco-2 cell lines (<10%) | |||
Polymethylmethacrylate, 25 nm, spherical, negative charge, hydrophilic | Virgin | In vitro, exposure to Caco-2 cell line | Poor uptake, observation of transport through the monolayer simulated by Caco-2 cell line (>10%) | |
Polylactic acid 250 nm, spherical, negative charge | Cellular uptake (potential clathrin-mediated endocytosis) and transport through the monolayer simulated by the Caco-2 cell line (<10%) | |||
Melamine formaldehyde resin, 366 nm, spherical, positive charge, hydrophilic | Cellular uptake (potential endocytosis mediated by caveolin or macropinocytosis) and transport through the monolayer simulated by the Caco-2 cell line (<10%) | |||
Polylactic acid 2 μm, spherical, negative charge | Cellular uptake (potential macropinocytosis) and transport through the monolayer simulated by Caco-2 cell line (<10%) | |||
Carboxylate-modified polystyrene, 40 nm and 200 nm, negative charged | Virgin | In vivo (mice) | Observation of nanoplastics in intestinal sections; no investigation of the mechanism of overcoming intestinal barriers and uptake; hypothesized clathrin-dependent endocytosis based on similar studies | |
Polystyrene, 25 nm, spherical, negative charge | Virgin | In vivo (mice, only male) | Mitochondrial damage observed in liver cells | |
Polystyrene, 50 nm, no aggregation tendency | Virgin | In vivo (mice) | Observation of nanoplastics in the intestinal sections of the intestine; no investigation of the mechanism for overcoming intestinal barriers and uptake | |
Polystyrene, 100 nm, spherical, carboxyl and amino-modified, hydrophilic | Virgin | In vitro, exposure to Caco-2 cell line | Clathrin-dependent endocytosis in the Caco-2 cell line, tested with endocytic pathway inhibitors with rupture of the close junction between Caco-2 cells; increased uptake for amino-e-carbolisyl-modified nanoplastics | |
In vivo (mice, only male) | Observation of nanoplastics in the intestinal sections of the tender and gross | |||
Polystyrene, 100 nm, spherical, carbon-modified, negative charge | Virgin | In vitro | Endocytosis mediated by caveolae on GES-1 cell line (mean rate of internalization) tested using the inhibitors of endocytic mechanisms | |
In vivo (mice, only male) | NA | |||
Polystyrene, 100 nm, spherical, amino-modified, positive charge | Virgin | In vitro | Endocytosis mediated by caveolae on GES-1 cell line (high internalization rate) tested using inhibitors of endocytic mechanisms | |
In vivo (mice, only male) | NA | |||
Polystyrene, 100 nm, spherical, neutral charged | Virgin | In vitro | Caveola-mediated endocytosis on GES-1 cell line (low internalization rate) tested using inhibitors of endocytic mechanisms | |
In vivo (mice, only male) | Observation of nanoplastics in the intestinal sections, stomach and liver; no investigation of the mechanism for overcoming intestinal barriers and uptake | |||
Polystyrene, 20 nm, 500 nm, slightly negative charge, hydrophobic | Virgin | In vivo (mice) | Observation of nanoplastics in the intestine, distributed in intestinal villi and lamina propria; penetration of the mucus layer and presence in the epithelial cells of the intestinal epithelium | |
Polystyrene, 50 nm, spherical, negative charge, hydrophobic, potentially functionalized | Virgin | In vitro, exposure to Caco-2/HT29 + Raji-B cell lines | Observation of nanoplastics in the mucus layer and cells; no investigation of uptake mechanism | |
Polystyrene, 50 nm, spherical, negative, hydrophobic | Virgin | In vitro, exposure to Caco-2 cell line | Observation of nanoplastics in cells; no investigation of uptake mechanism | |
Polystyrene, 20 nm, neutral charge, spherical, hydrophobic | Virgin | In vitro (splenocytes extracted from mice) | No investigation of the uptake mechanism | |
Polystyrene, 20 nm, positively charged, hydrophilic, spherical | Virgin | In vitro (splenocytes extracted from mice | No investigation of the uptake mechanism | |
Polystyrene, 20 nm, negative charge, spherical hydrophilic tendency | Virgin | In vitro (splenocytes extracted from mice | No investigation of the uptake mechanism | |
Polystyrene, 50 nm, negative charge, spherical, hydrophobic | Virgin | In vitro (splenocytes extracted from mice | Internalization observed with higher rate than 20-nm nanoplastics; no investigation of the uptake mechanism | |
Polystyrene, 50–100 nm, negative charge | Virgin | In vitro, exposure to Caco-2 cell line | Observation of nanoplastics in cells, including nuclei in a concentration-dependent manner | |
Polystyrene, 50 nm, 500 nm and 5,000 nm, negative and positive charges, with surface modification with functional groups | Virgin | In vitro, exposure to RBL-2H3 cell line | Observation of lysosomal uptake for 50 nm and 500 nm; clathrin-dependent endocytosis for 50-nm nanoplastics, macropinocytosis for 500-nm nanoplastics tested using inhibitors of endocytic mechanisms | |
Polystyrene, 10 nm, 15 nm, 25 nm, 40 nm, 50 nm and 500 nm, spherical | Virgin | In vitro exposure to HeLa cell line | Observation of nanoplastics < 25 nm; for nanoplastics > 25 nm, less distribution and non-uniform assumed for passive diffusion | |
Amino-modified polystyrene, 100 nm, spherical | Virgin | In vitro, exposure to Caco-2 cell line | Observation of high internalization capacity in lysosomes compared to polystyrene and caboxyl-modified polystyrene nanoplastics; no investigation of the absorption mechanism | |
Polystyrene, 50 nm–10 μm, spherical | Virgin | In vitro exposure to the BeWo cell line b30 human placental trophoblastic barrier model | Observation of nanoplastics; no investigation of absorption mechanism | |
Weathered | Observation of nanoplastics; no investigation of absorption mechanism | |||
Polystyrene, 10 μm, spherical | Virgin | In vitro exposure to RAW264.7 macrophage and Caco-2 cell lines | Internalization mechanism not specified | |
Polystyrene, 10 μm, spherical | Weathered | RAW264.7 macrophages and Caco-2 cell lines; greater recognition by macrophages due to protein corona |
