Global DNA Compaction in Stationary-Phase Bacteria Does Not Affect Transcription.

In stationary-phase Escherichia coli, Dps (DNA-binding protein from starved cells) is the most abundant protein component of the nucleoid. Dps compacts DNA into a dense complex and protects it from damage. Dps has also been proposed to act as a global regulator of transcription. Here, we directly examine the impact of Dps-induced compaction of DNA on the activity of RNA polymerase (RNAP). Strikingly, deleting the dps gene decompacted the nucleoid but did not significantly alter the transcriptome and only mildly altered the proteome during stationary phase. Complementary in vitro assays demonstrated that Dps blocks restriction endonucleases but not RNAP from binding DNA. Single-molecule assays demonstrated that Dps dynamically condenses DNA around elongating RNAP without impeding its progress. We conclude that Dps forms a dynamic structure that excludes some DNA-binding proteins yet allows RNAP free access to the buried genes, a behavior characteristic of phase-separated organelles.

Soft, malleable double diamond twin.

A twin boundary (TB) is a common low energy planar defect in crystals including those with the atomic diamond structure (C, Si, Ge, etc.). We study twins in a self-assembled soft matter block copolymer (BCP) supramolecular crystal having the double diamond (DD) structure, consisting of two translationally shifted, interpenetrating diamond networks of the minority polydimethyl siloxane block embedded in a polystyrene block matrix. The coherent, low energy, mirror-symmetric double tubular network twin has one minority block network with its nodes offset from the (222) TB plane, while nodes of the second network lie in the plane of the boundary. The offset network, although at a scale about a factor of 103 larger, has precisely the same geometry and symmetry as a (111) twin in atomic single diamond where the tetrahedral units spanning the TB retain nearly the same strut (bond) lengths and strut (bond) angles as in the normal unit cell. In DD, the second network undergoes a dramatic restructuring-the tetrahedral nodes transform into two new types of mirror-symmetric nodes (pentahedral and trihedral) which alternate and link to form a hexagonal mesh in the plane of the TB. The collective reorganization of the supramolecular packing highlights the hierarchical structure of ordered BCP phases and emphasizes the remarkable malleability of soft matter.

Whole-genome detection using multivalent DNA-coated colloids.

To minimize the incorrect use of antibiotics, there is a great need for rapid and inexpensive tests to identify the pathogens that cause an infection. The gold standard of pathogen identification is based on the recognition of DNA sequences that are unique for a given pathogen. Here, we propose and test a strategy to develop simple, fast, and highly sensitive biosensors that make use of multivalency. Our approach uses DNA-functionalized polystyrene colloids that distinguish pathogens on the basis of the frequency of selected short DNA sequences in their genome. Importantly, our method uses entire genomes and does not require nucleic acid amplification. Polystyrene colloids grafted with specially designed surface DNA probes can bind cooperatively to frequently repeated sequences along the entire genome of the target bacteria, resulting in the formation of large and easily detectable colloidal aggregates. Our detection strategy allows "mix and read" detection of the target analyte; it is robust and highly sensitive over a wide concentration range covering, in the case of our test target genome Escherichia coli bl21-de3, 10 orders of magnitude from [Formula: see text] to [Formula: see text] copies/mL. The sensitivity compares well with state-of-the-art sensing techniques and has excellent specificity against nontarget bacteria. When applied to real samples, the proposed technique shows an excellent recovery rate. Our detection strategy opens the way to developing a robust platform for pathogen detection in the fields of food safety, disease control, and environmental monitoring.

Novel class of peptides disintegrating biological membranes to aid in the characterization of membrane proteins.

Styrene-maleic acid (SMA) and similar amphiphilic copolymers are known to cut biological membranes into lipid nanoparticles/nanodiscs containing membrane proteins apparently in their relatively native membrane lipid environment. Our previous work demonstrated that membrane raft microdomains resist such disintegration by SMA. The use of SMA in studying membrane proteins is limited by its heterogeneity and the inability to prepare defined derivatives. In the present paper, we demonstrate that some amphiphilic peptides structurally mimicking SMA also similarly disintegrate cell membranes. In contrast to the previously used copolymers, the simple peptides are structurally homogeneous. We found that their membrane-disintegrating activity increases with their length (reaching optimum at 24 amino acids) and requires a basic primary structure, that is, (XXD)n, where X represents a hydrophobic amino acid (optimally phenylalanine), D aspartic acid, and n is the number of repeats of these triplets. These peptides may provide opportunities for various well-defined potentially useful modifications in the study of membrane protein biochemistry. Our present results confirm a specific character of membrane raft microdomains.

Cascade degradation and upcycling of polystyrene waste to high-value chemicals.

Plastic waste represents one of the most urgent environmental challenges facing humankind. Upcycling has been proposed to solve the low profitability and high market sensitivity of known recycling methods. Existing upcycling methods operate under energy-intense conditions and use precious-metal catalysts, but produce low-value oligomers, monomers, and common aromatics. Herein, we report a tandem degradation-upcycling strategy to exploit high-value chemicals from polystyrene (PS) waste with high selectivity. We first degrade PS waste to aromatics using ultraviolet (UV) light and then valorize the intermediate to diphenylmethane. Low-cost AlCl3 catalyzes both the reactions of degradation and upcycling at ambient temperatures under atmospheric pressure. The degraded intermediates can advantageously serve as solvents for processing the solid plastic wastes, forming a self-sustainable circuitry. The low-value-input and high-value-output approach is thus substantially more sustainable and economically viable than conventional thermal processes, which operate at high-temperature, high-pressure conditions and use precious-metal catalysts, but produce low-value oligomers, monomers, and common aromatics. The cascade strategy is resilient to impurities from plastic waste streams and is generalizable to other high-value chemicals (e.g., benzophenone, 1,2-diphenylethane, and 4-phenyl-4-oxo butyric acid). The upcycling to diphenylmethane was tested at 1-kg laboratory scale and attested by industrial-scale techno-economic analysis, demonstrating sustainability and economic viability without government subsidies or tax credits.

Nanopore Blockade Sensors for Quantitative Analysis Using an Optical Nanopore Assay.

Nanopore sensing is a popular biosensing strategy that is being explored for the quantitative analysis of biomarkers. With low concentrations of analytes, nanopore sensors face challenges related to slow response times and selectivity. Here, we demonstrate an approach to rapidly detect species at ultralow concentrations using an optical nanopore blockade sensor for quantitative detection of the protein vascular endothelial growth factor (VEGF). This sensor relies on monitoring fluorescent polystyrene nanoparticles blocking nanopores in a nanopore array of 676 nanopores. The fluorescent signal is read out using a wide-field fluorescence microscope. Nonspecific blockade events are then distinguished from specific blockade events based on the ability to pull the particles out of the pore using an applied electric field. This allows the detection of VEGF at sub-picomolar concentration in less than 15 min.

Droplet Polymer Bilayers for Bioelectronic Membrane Interfacing.

Model membranes interfaced with bioelectronics allow for the exploration of fundamental cell processes and the design of biomimetic sensors. Organic conducting polymers are an attractive surface on which to study the electrical properties of membranes because of their low impedance, high biocompatibility, and hygroscopic nature. However, establishing supported lipid bilayers (SLBs) on conducting polymers has lagged significantly behind other substrate materials, namely, for challenges in membrane electrical sealing and stability. Unlike SLBs that are highly dependent on surface interactions, droplet interface bilayers (DIBs) and droplet hydrogel bilayers (DHBs) leverage the energetically favorable organization of phospholipids at atomically smooth liquid interfaces to build high-integrity membranes. For the first time, we report the formation of droplet polymer bilayers (DPBs) between a lipid-coated aqueous droplet and the high-performing conducting polymer poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS). The resulting bilayers can be produced from a range of lipid compositions and demonstrate strong electrical sealing that outcompetes SLBs. DPBs are subsequently translated to patterned and planar microelectrode arrays to ease barriers to implementation and improve the reliability of membrane formation. This platform enables more reproducible and robust membranes on conducting polymers to further the mission of merging bioelectronics and synthetic, natural, or hybrid bilayer membranes.

Novel Polystyrene-Binding Nanobody for Enhancing Immunoassays: Insights into Affinity, Immobilization, and Application Potential.

Nanobodies, which represent the next generation of antibodies due to their unique properties, face a significant limitation in their poor physical adsorption on solid supports. In this study, we successfully discovered polystyrene binding nanobodies from a synthetic nanobody library. Notably, bivalent nanobody B2 exhibited high affinity for polystyrene (0.7 nM for ELISA saturation binding analysis and 15.6 nM for isothermal titration calorimetry), displaying a pH-dependent behavior. Remarkably, hydrophobic and electrostatic interactions contribute minimally to the binding process. Molecular modeling provided insights into the interaction between B2 and polystyrene, revealing that the Trp51 residue within the CDR2 loop formed an aromatic H-bond with polystyrene at a distance of 2.74 Å, thus explaining the observed reduction in B2 affinity caused by Trp51 mutations. To explore B2's potential in protein immobilization, we constructed a bispecific nanobody by fusing B2 to an anticarcinoembryonic antigen nanobody 11C12, which cannot be immobilized on polystyrene through passive adsorption. Remarkably, the fusion construct achieved effective immobilization on polystyrene within 5 min by passing the need for periplasmic protein purification despite its low expression level. Moreover, the fusion construct demonstrated excellent linearity in the chemiluminescent enzyme immunoassay. For the first time, this study reports a simplified and seamless platform for the oriented immobilization of nanobody. Importantly, the entire process eliminated the need for protein purification, enabling efficient and rapid immobilization of fusion proteins directly from crude cell extracts, even when the expression level was low. Our developed process dramatically reduced the processing time from 2.5 days to just 5 min.

Unraveling Intracellular Protein Corona Components of Nanoplastics via Photocatalytic Protein Proximity Labeling.

Bioaccumulation of nanoplastic particles has drawn increasing attention regarding environmental sustainability and biosafety. How nanoplastic particles interact with the cellular milieu still remains elusive. Herein, we exemplify a general approach to profile the composition of a "protein corona" interacting with nanoparticles via the photocatalytic protein proximity labeling method. To enable photocatalytic proximity labeling of the proteome interacting with particles, iodine-substituted BODIPY (I-BODIPY) is selected as the photosensitizer and covalently conjugated onto amino-polystyrene nanoparticles as a model system. Next, selective proximity labeling of interacting proteins is demonstrated using I-BODIPY-labeled nanoplastic particles in both Escherichia coli lysate and live alpha mouse liver 12 cells. Mechanistic studies reveal that the covalent modifications of proteins by an aminoalkyne substrate are conducted via a reactive oxygen species photosensitization pathway. Further proteomic analysis uncovers that mitochondria-related proteins are intensively involved in the protein corona, indicating substantial interactions between nanoplastic particles and mitochondria. In addition, proteostasis network components are also identified, accompanied by consequent cellular proteome aggregation confirmed by fluorescence imaging. Together, this work exemplifies a general strategy to interrogate the composition of the protein corona of nanomaterials by endowing them with photooxidation properties to enable photocatalytic protein proximity labeling function.

Accurate and High-Resolution Particle Mass Measurement Using a Peak Filtering Algorithm.

Charge detection quadrupole ion trap mass spectrometry (CD-QIT MS) is an effective way of achieving the mass analysis of microparticles with ultrahigh mass. However, its mass accuracy and resolution are still poor. To enhance the performance of CD-QIT MS, the resolution Rpeak of each peak in the mass spectra resulting from an individual particle was assessed, and a peak filtering algorithm that can filter out particle adducts and clusters with a lower Rpeak was proposed. By using this strategy, more accurate mass information about the analyzed particles could be obtained, and the mass resolution of CD-QIT MS was improved by nearly 2-fold, which was demonstrated by using the polystyrene (PS) particle size standards and red blood cells (RBCs). Benefiting from these advantages of the peak filtering algorithm, the baseline separation and relative quantification of 3 and 4 µm PS particles were achieved. To prove the application value of this algorithm in a biological system, the mass of yeast cells harvested at different times was measured, and it was found that the mixed unbudded and budded yeast cells, which otherwise would not be differentiable, were distinguished and quantified with the algorithm.

Real-Time Monitoring of the Evaporation and Fission of Electrospray-Ionized Polystyrene Beads and Bacterial Pellets at Elevated Temperatures.

This study uses real-time monitoring, at microsecond time scales, with a charge-sensing particle detector to investigate the evaporation and fission processes of methanol/micrometer-sized polystyrene beads (PS beads) droplets and bacterial particles droplets generated via electrospray ionization (ESI) under elevated temperatures. By incrementally raising capillary temperatures, the solvent, such as methanol on 0.75 µm PS beads, experiences partial evaporation. Further temperature increase induces fission, and methanol molecules continue to evaporate until PS ions are detected after this range. Similar partial evaporation is observed on 3 µm PS beads. However, the shorter period of the fission temperature range is necessary compared to 0.75 µm PS beads. For the spherical-shaped bacterium, Staphylococcus aureus, the desolvation process shows a similar fission period as compared to 0.75 µm PS beads. Comparably, the rod-shaped bacteria, Escherichia coli EC11303, and E. coli strain W have shorter fission periods than S. aureus. This research provides insights into the evaporation and fission mechanisms of ESI droplets containing different sizes and shapes of micrometer-sized particles, contributing to a better understanding of gaseous macroion formation.

Dual Engine Boosts Organic Photoelectrochemical Transistor for Enhanced Modulation and Bioanalysis.

Organic photoelectrochemical transistor (OPECT) has shown substantial potential in the development of next-generation bioanalysis yet is limited by the either-or situation between the photoelectrode types and the channel types. Inspired by the dual-photoelectrode systems, we propose a new architecture of dual-engine OPECT for enhanced signal modulation and its biosensing application. Exemplified by incorporating the CdS/Bi2S3 photoanode and Cu2O photocathode within the gate-source circuit of Ag/AgCl-gated poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) channel, the device shows enhanced modulation capability and larger transconductance (gm) against the single-photoelectrode ones. Moreover, the light irritation upon the device effectively shifts the peak value of gm to zero gate voltage without degradation and generates larger current steps that are advantageous for the sensitive bioanalysis. Based on the as-developed dual-photoelectrode OPECT, target-mediated recycling and etching reactions are designed upon the CdS/Bi2S3, which could result in dual signal amplification and realize the sensitive microRNA-155 biodetection with a linear range from 1 fM to 100 pM and a lower detection limit of 0.12 fM.

Membrane-Free Lateral Flow Assay with the Active Control of Fluid Transport for Ultrasensitive Cardiac Biomarker Detection.

Membrane-based lateral flow immunoassays (LFAs) have been employed as early point-of-care (POC) testing tools in clinical settings. However, the varying membrane properties, uncontrollable sample transport in LFAs, visual readout, and required large sample volumes have been major limiting factors in realizing needed sensitivity and desirable precise quantification. Addressing these challenges, we designed a membrane-free system in which the desirable three-dimensional (3D) structure of the detection zone is imitated and used a small pump for fluid flow and fluorescence as readout, all the while maintaining a one-step assay protocol. A hydrogel-like protein-polyelectrolyte complex (PPC) within a polyelectrolyte multilayer (PEM) was developed as the test line by complexing polystreptavidin (pSA) with poly(diallyldimethylammonium chloride) (PDDA), which in turn was layered with poly(acrylic acid) (PAA) resulting in a superior 3D streptavidin-rich test line. Since the remainder of the microchannel remains material-free, good flow control is achieved, and with the total volume of 20 µL, 7.5-fold smaller sample volumes can be used in comparison to conventional LFAs. High sensitivity with desirable reproducibility and a 20 min total assay time were achieved for the detection of NT-proBNP in plasma with a dynamic range of 60-9000 pg·mL-1 and a limit of detection of 56 pg·mL-1 using probe antibody-modified fluorescence nanoparticles. While instrument-free visual detection is no longer possible, the developed lateral flow channel platform has the potential to dramatically expand the LFA applicability, as it overcomes the limitations of membrane-based immunoassays, ultimately improving the accuracy and reducing the sample volume so that finger-prick analyses can easily be done in a one-step assay for analytes present at very low concentrations.

Protein Binding Leads to Reduced Stability and Solvated Disorder in the Polystyrene Nanoparticle Corona.

Understanding the conformation of proteins in the nanoparticle corona has important implications in how organisms respond to nanoparticle-based drugs. These proteins coat the nanoparticle surface, and their properties will influence the nanoparticle's interaction with cell targets and the immune system. While some coronas are thought to be disordered, two key unanswered questions are the degree of disorder and solvent accessibility. Here, a model is developed for protein corona disorder in polystyrene nanoparticles of varying size. For two different proteins, it is found that binding affinity decreases as nanoparticle size increases. The stoichiometry of binding, along with changes in the hydrodynamic size, supports a highly solvated, disordered protein corona anchored at a small number of attachment sites. The scaling of the stoichiometry versus nanoparticle size is consistent with disordered polymer dimensions. Moreover, it is found that proteins are destabilized less in the presence of larger nanoparticles, and hydrophobic exposure decreases at lower curvatures. The observations hold for proteins on flat polystyrene surfaces, which have the lowest hydrophobic exposure. The model provides an explanation for previous observations of increased amyloid fibrillation rates in the presence of larger nanoparticles, and it may rationalize how cell receptors can recognize protein disorder in therapeutic nanoparticles.

A Multisystemic Approach Revealed Aminated Polystyrene Nanoparticles-Induced Neurotoxicity.

Exposure to plastic nanoparticles has dramatically increased in the last 50 years, and there is evidence that plastic nanoparticles can be absorbed by organisms and cross the blood-brain-barrier (BBB). However, their toxic effects, especially on the nervous system, have not yet been extensively investigated, and most of the knowledge is based on studies using different conditions and systems, thus hard to compare. In this work, physicochemical properties of non-modified polystyrene (PS) and amine-functionalized PS (PS-NH2 ) nanoparticles are initially characterized. Advantage of a multisystemic approach is then taken to compare plastic nanoparticles effects in vitro, through cytotoxic readouts in mammalian cell culture, and in vivo, through behavioral readouts in the nematode Caenorhabditis elegans (C. elegans), a powerful 3R-complying model organism for toxicology studies. In vitro experiments in neuroblastoma cells indicate a specific cytotoxic effect of PS-NH2 particles, including a decreased neuronal differentiation and an increased Amyloid ß (Aß) secretion, a sensitive readout correlating with Alzheimer's disease pathology. In parallel, only in vivo treatments with PS-NH2 particles affect C. elegans development, decrease lifespan, and reveal higher sensitivity of animals expressing human Aß compared to wild-type animals. In summary, the multisystemic approach discloses a neurotoxic effect induced by aminated polystyrene nanoparticles.

Polystyrene-Based Matrix to Enhance the Fluorescence of Aggregation-Induced Emission Luminogen for Fluorescence-Guided Surgery.

Achieving ultrabright fluorogens is a key issue for fluorescence-guided surgery (FGS). Fluorogens with aggregation-induced emission (AIEgens) are potential agents for FGS on the benefit of the bright fluorescence in physiological conditions. Herein, the fluorescence brightness of AIEgen is further improved by preparing the nanoparticle using a polystyrene-based matrix and utilizing it for tumor FGS with a high signal-to-background ratio. After encapsulating AIEgen into polystyrene-poly (ethylene glycol) (PS-PEG), the fluorescence intensity of the prepared AIE@PS-PEG nanoparticles is multiple times that of nanoparticles in 1, 2-distearoyl-sn-glycero-3-phosphoethanolamine-poly (ethylene glycol) (DSPE-PEG), a commonly used polymer matrix for nanoparticle preparation. Molecular dynamics simulations suggest that higher free energy is required for the outer rings of AIEgen to rotate in polystyrene than in the DSPE, indicating that the benzene rings in polystyrene can restrict the intramolecular motions of AIEgen better than the alkyl chain in DSPE-PEG. Fluorescence correlation microscopy detections suggest that the triplet excited state of AIEgens is less in PS-PEG than in DSPE-PEG. The restricted intramolecular motions and suppressed triplet excited state result in ultrabright AIE@PS-PEG nanoparticles, which are more conducive to illuminating tumor tissues in the intestine for FGS. The illumination of metastatic tumors in lungs by AIE@PS-PEG nanoparticles is also tried.

Nanoplastic Stimulates the Amyloidogenesis of Parkinson's Alpha-Synuclein NACore.

Environmental plastic wastes are potential health hazards due to their prevalence as well as their versatility in initiating physical, chemical, and biological interactions and transformations. Indeed, recent research has implicated the adverse effects of micro- and nano-plastics, including their neurotoxicity, yet how plastic particulates may impact the aggregation pathway and toxicity of amyloid proteins pertinent to the pathologies of neurological diseases remains unknown. Here, electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS) is employed to reveal the polymorphic oligomerization of NACore, a surrogate of alpha-synuclein that is associated with the pathogenesis of Parkinson's disease. These data indicate that the production rate and population of the NACore oligomers are modulated by their exposure to a polystyrene nanoplastic, and these cellular assays further reveal an elevated NACore toxicity in microglial cells elicited by the nanoplastic. These simulations confirm that the nanoplastic-NACore association is promoted by their hydrophobic interactions. These findings are corroborated by an impairment in zebrafish hatching, survival, and development in vivo upon their embryonic exposure to the nanoplastic. Together, this study has uncovered the dynamics and mechanism of amyloidogenesis elevated by a nanoplastic trigger, shedding a new light on the neurological burden of plastic pollution.

Engineering Proteins for PEDOT Dispersions: A New Horizon for Highly Mixed Ionic-Electronic Biocompatible Conducting Materials.

Poly (3,4-ethylenedioxythiophene) (PEDOT) doped with polystyrene sulfonate (PSS) is the most used conducting polymer from energy to biomedical applications. Despite its exceptional properties, there is a need for developing new materials that can improve some of its inherent limitations, e.g., biocompatibility. In this context, doping PEDOT is propose with a robust recombinant protein with tunable properties, the consensus tetratricopeptide repeated protein (CTPR). The doping consists of an oxidative polymerization, where the PEDOT chains are stabilized by the negative charges of the CTPR protein. CTPR proteins are evaluated with three different lengths (3, 10, and 20 identical CTPR units) and optimized varied synthetic conditions. These findings revealed higher doping rate and oxidized state of the PEDOT chains when doped with the smallest scaffold (CTPR3). These PEDOT:CTPR hybrids possess ionic and electronic conductivity. Notably, PEDOT:CTPR3 displayed an electronic conductivity of 0.016 S cm-1, higher than any other reported protein-doped PEDOT. This result places PEDOT:CTPR3 at the level of PEDOT-biopolymer hybrids, and brings it closer in performance to PEDOT:PSS gold standard. Furthermore, PEDOT:CTPR3 dispersion is successfully optimized for inkjet printing, preserving its electroactivity properties after printing. This approach opens the door to the use of these novel hybrids for bioelectronics.

New Sight of Renal Toxicity Caused by UV-Aged Polystyrene Nanoplastics: Induced Ferroptosis via Adsorption of Transferrin.

Secondary nanoplastics (NPs) caused by degradation and aging due to environmental factors are the main source of human exposure, and alterations in the physicochemical and biological properties of NPs induced by environmental factors cannot be overlooked. In this study, pristine polystyrene (PS) NPs to obtain ultraviolet (UV)-aged PS NPs (aPS NPs) as secondary NPs is artificially aged. In a mouse oral exposure model, the nephrotoxicity of PS NPs and aPS NPs is compared, and the results showed that aPS NPs exposure induced more serious destruction of kidney tissue structure and function, along with characteristic changes in ferroptosis. Subsequent in vitro experiments revealed that aPS NPs-induced cell death in human renal tubular epithelial cells involved ferroptosis, which is supported by the use of ferrostatin-1, a ferroptosis inhibitor. Notably, it is discovered that aPS NPs can enhance the binding of serum transferrin (TF) to its receptor on the cell membrane by forming an aPS-TF complex, leading to an increase in intracellular Fe2+ and then exacerbation of oxidative stress and lipid peroxidation, which render cells more sensitive to ferroptosis. These findings indicated that UV irradiation can alter the physicochemical and biological properties of NPs, enhancing their kidney biological toxicity risk by inducing ferroptosis.

Chemically-Induced Lipoprotein Breakdown for Improved Extracellular Vesicle Purification.

Extracellular vesicles (EVs) are nanosized biomolecular packages involved in intercellular communication. EVs are released by all cells, making them broadly applicable as therapeutic, diagnostic, and mechanistic components in (patho)physiology. Sample purity is critical for correctly attributing observed effects to EVs and for maximizing therapeutic and diagnostic performance. Lipoprotein contaminants represent a major challenge for sample purity. Lipoproteins are approximately six orders of magnitude more abundant in the blood circulation and overlap in size, shape, and density with EVs. This study represents the first example of an EV purification method based on the chemically-induced breakdown of lipoproteins. Specifically, a styrene-maleic acid (SMA) copolymer is used to selectively breakdown lipoproteins, enabling subsequent size-based separation of the breakdown products from plasma EVs. The use of the polymer followed by tangential flow filtration or size-exclusion chromatography results in improved EV yield, preservation of EV morphology, increased EV markers, and reduced contaminant markers. SMA-based EV purification enables improved fluorescent labeling, reduces interactions with macrophages, and enhances accuracy, sensitivity, and specificity to detect EV biomarkers, indicating benefits for various downstream applications. In conclusion, SMA is a simple and effective method to improve the purity and yield of plasma-derived EVs, which favorably impacts downstream applications.