Low Ionic Strength Solutions Research Articles

ATP-induced reconfiguration of the micro-viscoelasticity of cardiac and skeletal myosin solutions.

We study the high-frequency, micro-mechanical response of suspensions composed of cardiac and skeletal muscle myosin by optical trapping interferometry. We observe that in low ionic strength solutions, upon the addition of magnesium adenosine triphosphate (MgATP2-), myosin suspensions radically change their micro-mechanics properties, generating a viscoelastic fluid characterized by a complex modulus similar to a suspension of worm-like micelles. This transduction of energy, from chemical to mechanical, may be related to the relaxed states of myosin, which regulate muscle contractility and can be involved in the etiology of many myopathies. Within an analogous generic mechanical response, cardiac and skeletal myosin suspensions provide different stress relaxation times, elastic modulus values, and characteristic lengths. These discrepancies probably rely on the dissimilar physiological functions of cardiac and skeletal muscle, on the different MgATPase hydrolysis rates of cardiac and skeletal myosins, and on the observed distinct cooperative behavior of their myosin heads in the super-relaxed state. In vitro studies like these allow us to understand the foundations of muscle cell mechanics on the micro-scale, and may contribute to the engineering of biological materials whose micro-mechanics can be activated by energy regulators.

Plasmid size determines adsorption to clay and breakthrough in a saturated sand column

Horizontal gene transfer (HGT) is a major factor in the spread of antibiotic resistant genes (ARG). Transformation, one mode of HGT, involves the acquisition and expression of extracellular DNA (eDNA). eDNA in soils is degraded rapidly by extracellular nucleases. However, if bound to a clay particle, eDNA can persist for long periods of time without losing its transformation ability. To better understand the mechanism of eDNA persistence in soil, this experiment assessed the effects of 1) clay mineralogy, 2) mixed salt solution, 3) plasmid size on DNA adsorption to clay and 4) breakthrough behavior of three differently sized plasmids in an environmentally relevant solution. Batch test methods were used to determine adsorption trends of three differently sized DNA plasmids, pUC19, pBR322, and pTYB21, to several pure clay minerals, goethite (α-FeOOH), illite, and kaolinite, and one environmental soil sample. Results show not all sorbents have equal adsorption capacity based on surface area with adsorption capacities decreasing from goethite > illite = kaolinite > bulk soil, and low ionic strength solutions will likely not significantly alter sorption trends. Additionally, plasmid DNA size (i.e., length) was shown to be a significant predictor of adsorption efficiency and that size affects DNA breakthrough, with breakthroughs occurring later with larger plasmids. Given that DNA persistence is linked to its adsorption to soil constituents and breakthrough, eDNA size is likely an important contributor to the spread of ARG within natural microbial communities.

Countercurrent preferential precipitation of acidic variants from monoclonal antibody pools

The process of countercurrent multistage precipitation (CnMP) was developed for reduction of the acidic variant (av) content in monoclonal antibody (mAb) pools. The process was performed in polyethylene glycol (PEG) solutions of low ionic strength, at which av was the most prone to precipitate. To design the process, a mathematical model was formulated, which consisted of steady-state mass balance equations and underlying thermodynamic dependencies. The model was solved for different combinations of the process variables, including the protein concentration in the feed material and the PEG concentration in subsequent precipitation stages. The model solution was projected onto two-dimensional planes, where the performance indicators, such as the separation yield and the av reduction level, were correlated with the process variables. CnMP overperformed crosscurrent multistage precipitation (CsMP) and ion exchange chromatography (IEX) used in previous studies; in the comparison with CsMP, the 3-stage CnMP process allowed up to 28% increase in yield and up to 25% increase in the av reduction level, and in the comparison with IEX, up to 37% increase in yield and up 12.5% increase in the av reduction level. The yield benefit of CnMP depended on the composition of the feed material and the demand for the av reduction. The concept was experimentally verified; the 2- and 3-stage CnMP processes were performed using the input process variables provided by the model solution. The performance indicators calculated by the model and experimentally measured were in a good agreement, which indicated both feasibility and predictability of CnMP.

SARS-CoV-2 detection by using graphene FET arrays with a portable microfluidic measurement system

We developed graphene FET (G-FET) arrays combined with a portable microfluidic measurement system for SARS-CoV-2 detection. Multiple G-FETs modified with SARS-CoV-2 spike antibodies and those not modified were integrated onto the same chip. By calculating the difference in the FET-responses, we aimed to minimize noise including virus physisorption and baseline drifts. The microfluidic system was used to change ionic strengths of buffers without manual pipetting. The virus was incubated in a high ionic strength solution, followed by electrical measurements in a low ionic strength solution, leading to effective binding and electrical detection. Upon introducing the virus at a concentration of 108 virus ml−1, a response of 7.9 mV was obtained. To confirm whether the response was attributed to the virus, we employed a scanning electron microscope (SEM). SEM observation indicates that the virus was much adsorbed on the antibody-modified surface compared to the non-modified surface, which agrees with the G-FET response.

Dual-crosslinked starch/carboxymethyl cellulose blend film with ion-responsive dissolution properties

While the ability of quickly vanishing in water has made starch-based plastics a potential solution to the current marine plastic issue caused by discarded single-use plastics, this ability also translates into lack of water resistance in daily scenario. Here, we aim to improve the water resistance of starch-based blend films in daily scenarios while allowing them to disintegrate and vanish rapidly in marine environments via the introduction of ionic crosslinks. A dialdehyde starch (DAS)/carboxymethyl cellulose (CMC) blend film is prepared via a modified solution casting process, during which DAS is gradually rendered cationic by a cationizing reagent, Girard's reagent T, and interacts with CMC to form ionic crosslinks. Meanwhile, the aldehyde groups on DAS also form acetal bonds with the -OH groups on both DAS and CMC, which further increases the wet strength. In solutions of low ionic strength encountered in daily life, such as freshwater, the film remains stable for both types of crosslinks. In high-ionic-strength solutions, such as seawater, the film swells rapidly and disintegrates owing to the cleavage of ionic crosslinks. This study demonstrated ionic crosslink could be a potential solution for balancing the protection of marine ecosystem and ease of use of starch-based blend films, which is essential to the development of future marine ecosystem-friendly single-use plastics.

Molecular structure of soluble vimentin tetramers

Intermediate filaments (IFs) are essential constituents of the metazoan cytoskeleton. A vast family of cytoplasmic IF proteins are capable of self-assembly from soluble tetrameric species into typical 10–12 nm wide filaments. The primary structure of these proteins includes the signature central ‘rod’ domain of ~ 300 residues which forms a dimeric α-helical coiled coil composed of three segments (coil1A, coil1B and coil2) interconnected by non-helical, flexible linkers (L1 and L12). The rod is flanked by flexible terminal head and tail domains. At present, the molecular architecture of mature IFs is only poorly known, limiting our capacity to rationalize the effect of numerous disease-related mutations found in IF proteins. Here we addressed the molecular structure of soluble vimentin tetramers which are formed by two antiparallel, staggered dimers with coil1B domains aligned (A11 tetramers). By examining a series of progressive truncations, we show that the presence of the coil1A domain is essential for the tetramer formation. In addition, we employed a novel chemical cross-linking pipeline including isotope labelling to identify intra- and interdimeric cross-links within the tetramer. We conclude that the tetramer is synergistically stabilized by the interactions of the aligned coil1B domains, the interactions between coil1A and the N-terminal portion of coil2, and the electrostatic attraction between the oppositely charged head and rod domains. Our cross-linking data indicate that, starting with a straight A11 tetramer, flexibility of linkers L1 and L12 enables ‘backfolding’ of both the coil1A and coil2 domains onto the tetrameric core formed by the coil1B domains. Through additional small-angle X-ray scattering experiments we show that the elongated A11 tetramers dominate in low ionic strength solutions, while there is also a significant structural flexibility especially in the terminal domains.

Spectroscopic characterization of the interactions between poly(2-(trimethylamino)ethyl methacrylate) chloride and the xanthene dyes, 2′, 7′-difluorofluorescein and 2, 4, 5, 7-tetraiodofluorescein

Intermolecular interactions in buffered aqueous solution between the polycation, poly(2-(trimethylamino)ethyl methacrylate) chloride (pTMAEMC) and two anionic xanthene dyes, 2′, 7′-difluorofluorescein (Oregon Green 488) and 2, 4, 5, 7-tetraiodofluorescein (Erythrosin B), are characterized using multiple optical spectroscopic methods. Visible absorption spectroscopy indicates the formation of ground-state pTMAEMC-dye complexes. Benesi-Hildebrand binding isotherm analysis of visible absorption spectra for pTMAEMC-dye mixtures quantifies the strength of binding interactions producing the complexes. For both Oregon Green 488 (OG) and Erythrosin B (EB) in mixtures with pTMAEMC, the concentration of the solution’s sodium acetate buffer at a fixed pH alters the binding constants, Kb, suggesting that ionic strength plays a key role in determining the binding affinity of pTMAEMC for the dyes. Comparison of Kb, for the dyes indicates stronger binding of EB under all solution conditions. Steady-state fluorescence emission spectroscopy, fluorescence quenching, excited-state fluorescence lifetime measurements and fluorescence correlation spectroscopy provide complementary data for the interactions between pTMAEMC and the dyes. Mixtures of pTMAEMC with the dyes produce fluorescence enhancements and fluorescence quenching which exhibit a dependence on the buffer concentration used in the mixture. Excited-state lifetime analysis indicates that OG interacts with pTMAEMC through ground-state interactions while EB exhibits both ground-state and excited-state interactions with pTMAEMC. The spectroscopic measurements suggest that a polyelectrolyte effect for pTMAEMC due to ionic strength variation produced by the buffer concentration affects the dye binding profile of the polycation. This conclusion is supported by fluorescence correlation spectroscopy (FCS) analyses of the hydrodynamic diameter changes in pTMAEMC-OG binding in low buffer concentration (low ionic strength) solution. FCS analyses of pTMAEMC-OG mixtures also reveal diversity in the complexes formed in low ionic strength solution suggesting that other xanthene dyes will exhibit similar binding behaviors in mixtures with pTMAEMC as a function of solution ionic strength.

L-histidine inhibits the heat-induced gelation of actomyosin in a low ionic strength solution.

The heat-induced gelation of actomyosin plays a key role in meat processing. Our previous study showed that L-histidine could affect the characteristics of a heat-induced gel of myosin on a low ionic strength. To apply the specific effect of L-histidine to meat processing, the heat-induced gel properties of actomyosin in the presence of L-histidine were investigated. Actomyosin in a low ionic strength solution containing L-histidine did not form a gel upon heating. The dynamic rheological properties of actomyosin in low ionic strength solutions were distinct depending on the presence or absence of L-histidine. Electron microscopy showed that, heated at 50°C, actomyosin in a low ionic strength solution containing L-histidine remained a filamentous structure. The surface hydrophobicity of actomyosin was stable up to 50°C in a low ionic strength solution containing L-histidine. In conclusion, L-histidine might suppress the aggregation of actomyosin and inhibit heat-induced gelation in a low ionic strength solution.

Cation modified Fe–N–C catalyst for the electrochemical reduction of nitrate in solutions of low ionic strength

Cationic sites fixed on an Fe–N–C catalyst modulate the electric field in the double layer and facilitate electrochemical nitrate reduction to ammonia in solutions of ionic strength comparable to that of actual river water.

Immunohematological Discrepancy – Due to Nuisance Antibody!

Timely provision of blood plays an important role in the management algorithm of patients. Interference by minor blood group (BG) antibodies has become a common entity among multi-transfused patients; other nonsignificant antibodies are too encountered rarely. We report one such interfering nonspecific antibody in a 55-year-old female patient posted for splenectomy at our institute. BG discrepancy (type one) with a pan-positive (4+) antibody screening panel was found in her testing results. Crossmatches were compatible at antihuman globulin phase and at room temperature, and autocontrol was negative. Detailed meticulous immunohematological workup helped us in concluding that the offending antibody was not directed against the ingredients of column matrix of gel cards or the enhancement media (low ionic strength solution); rather it was directed against the chemical constituents in the suspension medium of commercial cell panel. Bearing the presence of nonspecific “nuisance” antibodies in mind becomes extremely important so that they can be detected and managed quickly.

Dual Red Cell Alloimmunization with Anti-c and anti-E Antibodies

Background and Objectives: Alloimmunization can lead to difficulty in arranging compatible, antigen-negative blood units for the patients. Alloimmunization by coexisting “c” and “E” antibodies, though common, is frequently missed. Both “c” and “E” antigens are highly immunogenic and have the potential to cause hemolytic disease of newborn and hemolytic transfusion reactions. The objective of this study is to discuss different clinical scenarios of concomitant and singular presence of anti-c and anti-E along with the diagnostic approach and transfusion management in resource-limited settings. Methods: Column agglutination gel technology in low ionic strength solution phase was used for initial antibody identification. Detailed immunohematological workup was done by the use of select cells (c+, E− and c−, E+) and adsorption elution studies using a commercially available acid elution kit. Results: Out of 16 patients, detailed immunohematological workup was available for 14 patients, whereas two patients were lost to follow-up. Among 14 patients, 12 had CCDee (R1R1) phenotype, whereas two patients had CcDee phenotype (possible R1r) with anti-E antibody. In 12 patients with R1R1 phenotype, 6/12 (50%) had dual coexisting anti-c and E, whereas 3/12 (25%) had only anti-c and 3/12 (25%) had only anti-E. In R1R1 patients having anti-E, coexisting anti-c was found in 6/9 (66.66%) of patients. Conclusion: The study emphasizes the use of both “c” and “E” negative red cells (R1R1) in R1R1 patients having either anti-c or anti-E. Thus, in India, there is a need to develop our own red cell panels having an adequate representation of indigenous antigens and phenotypes.

Two different approaches to XPS quantitative analysis of polyelectrolyte adsorption layers

X‐ray photoelectron spectroscopy (XPS) was employed to quantify adsorption of polyelectrolytes from aqueous solutions of low ionic strength onto mica, glass, and silica. Silica surfaces were conditioned in base or in acid media as last pre‐treatment step (silica‐base last or silica‐acid last, respectively). Consistency in the determined adsorbed amount, Γ, was obtained independent of the choice of XPS mode and with the two quantification approaches used in the data evaluation. Under the same adsorption conditions, the adsorbed amount, Γ, varied as Γmica > Γsilica‐base last ≈ Γglass > Γsilica‐acid last. In addition, the adsorbed amount increased with decreasing polyelectrolyte charge density (100% to 1% of segments being charged) for all substrates. Large adsorbed amount was measured for low‐charge density polyelectrolytes, but the number of charged segments per square nanometer was low due to steric repulsion between polyelectrolyte chains that limited the adsorption. The adsorbed amount of highly charged polyelectrolytes was controlled by electrostatic interactions and thus limited to that needed to neutralize the substrate surface charge density. For silica, the adsorbed amount depended on the cleaning method, suggesting that this process influenced surface concentration and fraction of different silanol groups. Our results demonstrate that for silica, a higher density and/or more acidic silanol groups are formed using base, rather than acid, treatment in the last step.

Selecting the right elution buffer for mRNA purification using the POROS Oligo (dT)25 Affinity Resin

The POROS™ Oligo (dT)25 Affinity Resin helps to address the selectivity and capacity requirements for the large-scale manufacturing of mRNA used in vaccine and gene therapy applications. Typically, mRNA binds to the Oligo (dT)25 affinity resin using high ionic strength conditions and neutral pH and is eluted from the column using low ionic strength solutions such as water. Although water works well for most mRNA constructs, a need to identify alternative elution buffers to optimize mRNA recovery exists. This article describes experiments conducted to optimize mRNA purification using high-throughput screening.

Optimizing mRNA purification conditions by using a high-throughput screening approach

To support the development of mRNA-based therapies, Thermo Fisher Scientific has developed a platform chromatography solution for the purification of mRNA. The POROS™ Oligo (dT)25 Affinity Resin helps to address the selectivity and capacity requirements for the large-scale manufacturing of mRNA used in vaccine and gene therapy applications. Typically, mRNA binds to the Oligo (dT)25 affinity resin using high ionic strength conditions and neutral pH and is eluted from the column using low ionic strength solutions such as water. Although water works well for most mRNA constructs, a need to identify alternative elution buffers to optimize mRNA recovery exists. This article describes experiments conducted to optimize mRNA purification using high-throughput screening.

Salt-Induced Transitions in the Conformational Ensembles of Intrinsically Disordered Proteins.

Salts modulate the behavior of intrinsically disordered proteins (IDPs) and influence the formation of membraneless organelles through liquid-liquid phase separation (LLPS). In low ionic strength solutions, IDP conformations are perturbed by the screening of electrostatic interactions, independent of the salt identity. In this regime, insight into the IDP behavior can be obtained using the theory for salt-induced transitions in charged polymers. However, salt-specific interactions with the charged and uncharged residues, known as the Hofmeister effect, influence IDP behavior in high ionic strength solutions. There is a lack of reliable theoretical models in high salt concentration regimes to predict the salt effect on IDPs. We propose a simulation methodology using a coarse-grained IDP model and experimentally measured water to salt solution transfer free energies of various chemical groups that allowed us to study the salt-specific transitions induced in the IDPs conformational ensemble. We probed the effect of three different monovalent salts on five IDPs belonging to various polymer classes based on charged residue content. We demonstrate that all of the IDPs of different polymer classes behave as self-avoiding walks (SAWs) at physiological salt concentration. In high salt concentrations, the transitions observed in the IDP conformational ensembles are dependent on the salt used and the IDP sequence and composition. Changing the anion with the cation fixed can result in the IDP transition from a SAW-like behavior to a collapsed globule. An important implication of these results is that a suitable salt can be identified to induce condensation of an IDP through LLPS.

Freeze-thaw cycles induce diverse bacteria release behaviors from quartz sand columns with different water saturations

Bacteria present in natural environment especially those in cold regions would experience freeze-thaw (FT) process during day-night and season turns. However, knowledge about the influence of FT on bacteria release behaviors in porous media was limited. In present study, the bacteria release behaviors from quartz sand columns without and with 1 and 3 FT treatment cycles under three water saturations (θ=100%, 90%, and 60%) were investigated. We found that for all three water saturated columns without FT treatment, negligible bacteria released from columns via background salt solution elution, while the subsequent release of bacteria from sand columns via low ionic strength (IS) solution elution decreased with decreasing column water saturations. More importantly, we found unlike the negligible bacteria release in columns without FT treatment, for columns with high saturations (θ=100% and 90%), FT treatment could promote bacteria release with background salt solution elution. Moreover, for high saturated columns, FT treatment would decrease subsequent bacteria release with low IS solution elution. This phenomenon was more obvious with increasing FT treatment cycles. In contrast, FT treatment had negligible influence on bacteria release from columns with lower saturation (θ=60%). The decreased bacterial sizes, the loss of bacterial flagella, as well as the change of local configuration of porous media (via changing water into ice and ice back into water) during the FT processes contributed to increased bacteria release via background salt solution elution from high saturated sand columns. While, the reduced amount of bacteria being retained at secondary energy minima drove to the subsequently decreased bacteria release via low IS solution elution. The results of this study clearly showed that for porous media with high saturations, FT cycles would increase the risk of bacteria detaching from porous media with flushing by the background solution.

Study on the effect of ionic strength on particle migration and deposition in porous media covered by biofilm based on coupled Lattice Boltzmann method and Discrete element method

AbstractBiofilms covering porous media will interact with particles and affect particle migration. In order to investigate the migration mechanism of particles in porous media covered by biofilms, the migration process of particles with different particle sizes under the condition of the changing ionic strength is analyzed by using the lattice Boltzmann method–discrete element method (LBM‐DEM) coupling method from mesoscopic scale. The variation patterns of ion strength include gradient and mutation, respectively. Also, the agglomeration of particles at the pore throat in porous media is investigated under different conditions. The main results are obtained as follows. First, both the change of ionic strength and its changing mode significantly affect the migration behavior of particles in NaCl solution but have little effect on the behavior of particles in CaCl2 solution. Second, when the pressure difference between the pressure difference between the inlet and outlet of porous media is 0.4 kPa, the residual permeability of 1.5‐μm particles in the NaCl solution with ionic strength mutation is the highest, which has value of 64.92%. Third, at the specific flow rate, the particles in low ionic strength solution are more likely to be settled. The attraction of particles in the CaCl2 solution is one order of magnitude less than that in the NaCl solution, and the accumulated particles are more likely to be dispersed.

Type and screen method and Coombs crossmatch method for pretransfusion testing: A prospective comparative study in a tertiary care hospital in Delhi.

BACKGROUND:The aim of pretransfusion testing (PTT) is to prevent the immune-mediated hemolytic reaction by the transfusion of incompatible donor red cells. The methods of PTT have evolved over the years and a new method of type and screen (T and S) was introduced, in which only ABO grouping, Rh typing, and antibody screening would be carried out with omission of routine Coombs crossmatch. Although T and S is an accepted method for PTT in developed countries, only a few studies in literature have evaluated its efficacy in India.AIM AND OBJECTIVE:The aim of the study was to compare T and S method with conventional Coombs crossmatch method for PTT.MATERIALS AND METHODS:Two thousand and fifty samples were randomly selected from the samples received in blood bank for requisition of blood transfusion after taking informed consent. ABO blood grouping and Rh typing were performed for each recipient's sample. “T and S” and “Coombs crossmatch” were done simultaneously by two different persons without knowing the result of each test. A commercially available three cell panel was used for antibody screening, in which the recipient's plasma was reacted with red cells in the low ionic strength solution Coombs Gel card at 37°C by column agglutination technology.RESULTS:Antibody screening was positive in 29 (1.41%) patients and negative in 2021 (98.59%) patients. Out of 29 patients, 27 had alloantibodies and 2 had autoantibody. Most common alloantibody found in our study was anti-D. Other antibodies found were anti-K, anti-C + D, anti-E, anti-C, anti-c, anti-Jka, and anti-Mi (a). Crossmatch on first attempt was compatible in 2028 (98.93%) patients and incompatible in 22 (1.07%) patients. Out of 29 patients who were positive for antibody screening, crossmatch was incompatible in nine patients. Crossmatch was compatible in twenty patients, who had positive antibody screen. However, crossmatch compatibility in these patients, reflect either absence of corresponding antigen or antigen present in low dose (heterozygous) in donor blood. On the other hand, out of 22 patients incompatible on first crossmatch, antibody screening was negative in 13 patients and was positive in only nine patients. Hence, 13 patients with antibody would have been missed by antibody screen alone. Kappa statistics was used to compare the efficacy of “type and screening” and “Coombs crossmatch.” It showed κ =0.445 (P < 0.001) implying moderate agreement between the two variables of “T and S” and “Coombs crossmatch.”CONCLUSION:T and S is a scientifically better method but needs to be implemented with caution. We need to develop our own cell panels having adequate representation of indigenous antigen (including In, Mi (a), etc.,). Large-scale studies need to be done in India with indigenous screening cells to evaluate efficacy and safety of T and S method.

Influence of pore fluid-soil structure interactions on compacted lime-treated silty soil

The effects on hydromechanical performance due to chemical interactions between pore solution and soil components in lime-treated soil are investigated. Static- and kneading-compacted soils are percolated by demineralized water (DW) and a low-ionic strength solution. Kneading action causes aggregate deformation, thus consequently reducing macropores of diameter 105 Å. This increases the hydraulic tortuosity and lengthens the pore fluid-soil structure contact, which favors the long-term pozzolanic reactions. DW being relatively more aggressive than low-ionic strength solution accelerates the leaching of Calcium, thus negatively impacting the hydromechanical performance. The study shows that the hydromechanical evolution in lime-treated soil is governed by the duration of pore fluid and soil structure contact, depending on the compaction mechanisms implemented. The extent of the effect of pore fluid-soil structure interaction is regulated by the pore solution chemistry and the lime content. Thus, importance should be given to the relevancy of the selected compaction procedure and the permeant solution at the laboratory scale with respect to in-situ compaction mechanism and pore water.

Transport and deposition behaviors of microplastics in porous media: Co-impacts of N fertilizers and humic acid

Due to the interaction of fertilizers with microplastics (MPs) and porous media, fertilization process would influence MPs transport and distributions in soil. The co-impacts of N fertilizers (both inorganic and organic N fertilizers) and humic substance on MPs transport/retention behaviors in porous media were examined in 10 mM KCl solutions at pH 6. NH4Cl and CO(NH2)2 were employed as inorganic and organic N fertilizers, respectively, while humic acid (HA) was used as model humic substance. We found that for all three sized MPs (0.2, 1 and 2 µm) without HA, both types of N fertilizers decreased their transport/increased their retention in porous media (both quartz sand and soil). N fertilizers adsorbed onto surfaces of MPs and sand/soil, lowering the electrostatic repulsion between MPs and porous media, thus contributed to the enhanced MPs deposition. MPs with N fertilizers in solutions more tightly attached onto porous media and thus were more difficult to be re-mobilized by low ionic strength solution elution. Via steric repulsion and increasing electrostatic repulsion between MPs and porous media due to adsorption onto their surfaces, HA could increase MPs transport with N fertilizers in solutions.