BSA Protein Research Articles

Scrutinzing the interaction of bovine serum albumin and human hemoglobin with isatin-triazole functionalized rhodamine through spectroscopic and In-silico approaches

• Spectral methods have been used to investigate the interaction of R1 with HHb and BSA. • Thermodynamic parameters suggested exothermic spontaneous binding processes involving hydrogen bonding and van der Waal interaction. • Molecular docking and molecular dynamics have been utilized to discuss the principle binding sites of proteins for R1 . • R1 proposes preferentially binding to the hydrophobic cavity in site III of proteins. A Rhodamine-based fluorescent probe R1 has been successfully utilized to detect BSA and HHb proteins via non-covalent bonding. The protein binding nature with R1 has been unravelled by the characteristic changes in absorption, emission and circular dichroism spectra that indicated their noticeable interaction. The experimental results have also shown the moderate strength between proteins and R1 from the quenching of proteins through the static quenching mechanism. The hyperchromism in the absorption band of proteins with R1 has given vital information and binding affinity values have been calculated from Stern-Volmer plots. The calculated values of the thermodynamic parameters revealed a spontaneous binding processes occurring primarily via hydrogen bonding and van der Waal interactions. Furthermore, in-silico approaches have been utilized to make a comparison and conclusion with spectroscopic results. The outcome of these studies could be useful to examine the drug-protein binding for further exploitation.

Deciphering Dual Modes of Parkinsonian Biomolecules Derived Fluorescent Nanoparticles: Protein Specificity and White Light Generation.

Dopamine (DA) and 3,4-dihydroxy-l-phenylalanine (L-Dopa or DPA), a marker and medicine for the neurological disorder Parkinson's disease (PD), lead to the formation of polymeric fluorescent nanoparticles (F-Poly NPs or F-NPs or simply, NPs). The interaction study between proteins and NPs shows prominent interaction with strong specificity toward albumin type proteins for DPA derived and mixed NPs. Furthermore, encapsulation of the anticancer drug doxorubicin hydrochloride (Dox) inside the NP-protein conjugates results in excellent white light emission with pronounced specificity toward albumin proteins for F-PDPA and F-Mix NPs. Finally, the use of BSA protein fibril resulting in strong binding with NPs along with Dox assisted white light emission has also been studied.

Unique enantiopure camphor-based neutral arene–ruthenium(II) complexes: DNA/BSA binding, kinetic and cytotoxic studies

Two neutral enantiopure arene-ruthenium(II) complexes, [(arene)RuII(κ2(1S,3R)-Ar)Cl2] (1, 2), arene = p-cymene, Ar = o-tolyl or mesityl, derived from the reaction of arene-ruthenium(II) dimers and 1,3-diamino camphor based derivatives, were synthesized. The N1-mesityl-2,2,3-trimethylcyclopentane-1,3-diamine ligand and complex 2 are characterized via X-ray crystallography. Single crystal X-ray structure analysis revealed that 2 crystallizes in monoclinic space group P21 with Z = 4, a = 7.7724(14), b = 14.262(3), c = 14.433(3) Å. Reactivity measurements using UV-Vis of the RuII-arene complexes with guanosine-5′-monophosphate (5′-GMP), 9-methylguanine (9MeG), and L-methionine (L-Met) showed a high affinity towards these nucleophiles. Also, DFT calculations with 2 showed that the reaction with a guanine derivative is thermodynamically favored. Furthermore, the RuII-arene complexes were found to interact with CT-DNA and HT-DNA, and protein BSA. The cytotoxicities of 1 and 2 have been evaluated against human breast cancer cell line (MDA-MB), human cancer colon cell line (HCT-116), human lung carcinoma epithelial cell line (A549), mouse melanoma cell line (B16F10), and mesenchymal stem cells (MSCs) and compared to cisplatin as standard analog. The complexes display relevant activities against all cancer cell lines.

Structural elucidation, in vitro DNA binding and anticancer investigations of a new specific target dinuclear Zn(II) complex

In this study, dinuclear bis(2,2′-bipyridine)-tris{[μ-pyrimidin-2-yl)sulfanyl]acetato}Zn(II) perchlorate complex was synthesized and characterized by FT-IR, ESI-MS, 1H NMR and single-crystal X-ray diffraction studies. The bis(2,2′-bipyridine)-tris{[μ-pyrimidin-2-yl)sulfanyl]acetato}Zn(II) perchlorate was crystallized in a monoclinic crystal system having a P 21/c space group. The single-crystal structure of bis(2,2′-bipyridine)-tris{[μ-pyrimidin-2-yl)sulfanyl]acetato}Zn(II) perchlorate reveals that Zn1 is five coordinated and has adopted distorted square pyramidal geometry while as Zn2 centre is six coordinated and has adopted distorted octahedral geometry, bridged by three carboxylate groups of (2-pyrimidylthio) acetic acid (PTAA). Hirshfeld surface analysis and density functional theory were determined by crystallographic computational tools to investigate the contribution of non-covalent interactions, reactivity and stability of bis(2,2′-bipyridine)-tris{[μ-pyrimidin-2-yl)sulfanyl]acetato}Zn(II) perchlorate. In vitro, ct-DNA binding studies of the complex were accomplished by applying various spectroscopic and analytical techniques. The results obtained suggested a groove or electrostatic mode of binding. The bis(2,2′-bipyridine)-tris{[μ-pyrimidin-2-yl)sulfanyl]acetato}Zn(II) perchlorate has caused significant double-stranded scission of pBR322 DNA through the hydrolytic pathway as observed by the gel electrophoretic experiment. Cytotoxicity of bis(2,2′-bipyridine)-tris{[μ-pyrimidin-2-yl)sulfanyl]acetato}Zn(II) perchlorate was evaluated against MCF-7, MDA-MB-231, Hop-62, AW13516 and SiHa human cancer cell lines, which revealed a moderate anticancer response. In addition, binding studies of the bis(2,2′-bipyridine)-tris{[μ-pyrimidin-2-yl)sulfanyl]acetato}Zn(II) perchlorate with BSA protein were performed by fluorescence spectroscopy. The synchronous fluorescence spectra suggested the efficient binding of complex towards tyrosine than tryptophan. The quenching mechanism of BSA by complex was found static in nature.

Synthesis and application of MoS2 quantum dots-decorated ZnO nanoparticles for the fabrication of loose nanofiltration membranes with improved filtration, anti-fouling, and photocatalytic performance

MoS2 quantum dots (MoS2 QDs) have recently attracted extremely high consideration owing to their exclusive qualities related to both sheet-like structures and QDs. Doping MoS2 QDs with other semiconductors, such as ZnO nanoparticles (ZnO NPs), has provided superior synergistic effects on their performances. Herein, we constructed mixed matrix loose nanofiltration polyethersulfone (PES) membranes decorated with MoS2 QDs, ZnO NPs, and MoS2 QDs@ ZnO NPs (MNQs) separately, prepared by phase inversion method, for a comprehensive study of filtration, antifouling, and photocatalytic properties. Among all the prepared membranes, the MNQ0.5 membrane provides enhanced properties such as high permeation (15.46 ± 0.75 L/m.2 h. bar which is 11 times greater than control PES), significant rejection performance against Rhodamine B (Rh. B) (˃95 %), excellent photocatalytic activity (2.5 times greater than control PES), and outstanding anti-fouling features (FRR=93.14 %, reversible fouling ratios (Rr)= 39.17 %, irreversible fouling ratio (Rir)= 6.85 %, and total fouling ratio (Rt)= 46.02 %). Besides, the best anti-fouling performance was obtained by the MNQ0.5 membrane in comparison to that of the bare PES one, confirmed via BSA protein permeance.

Doubly modified MWCNTs embedded in polyethersulfone (PES) ultrafiltration membrane and its anti-fouling performance

Abstract Multiwall carbon nanotubes (MWCNTs) are often used to modify polymer membranes as additives, however, MWCNTs are easy to agglomerate and entangle in polymer matrix due to their own strong van der Waals force. MWCNTs were doubly modified by bonding octadecylamine (ODA) and SiO2 through the respective amidation and esterification reactions to prepare SiO2-MWCNT-ODA nanocomposites. The amino groups on ODA were amidated with the carboxyl groups on MWCNT-COOH. Then the hydroxyl groups on SiO2 were bonded to MWCNT-COOH through esterification to obtain SiO2-MWCNT-ODA nanocomposites. PES/SiO2-MWCNT-ODA composite ultrafiltration (UF) membrane was prepared by non-solvent induced phase separation (NIPS) method. SiO2-MWCNT-ODA nanocomposites and PES/SiO2-MWCNT-ODA membrane were characterized by FTIR, XRD, TGA, and SEM, etc. The results showed that PES/SiO2-MWCNT-ODA membrane had significantly improved permeability, rejection, and antifouling properties for comparison with PES membrane. The pure water flux of PES/Nano.2-0.5 reached 212.5 L m−2 h−1, which was approximately 2.6 times than that of PES membrane, and the rejection of BSA protein for composite membrane was as high as 94.2%. PES/SiO2-MWCNT-ODA composite membrane had excellent antifouling performance and the flux recovery rate (FRR) of PES/Nano.2-0.5 membrane could still maintain at higher value of 84.82% after two cycles in the antifouling test.

A Comparative Study on Total Muscle Protein Content of Different Fish Species in Fresh and Smoked - Dried Condition and to Analyze their Banding Pattern through SDS- PAGE

Fish plays an important role in human nutrition. They are known to be a very healthy food item. They are excellent protein sources that also deliver various minerals and vitamins necessary for good health. Due to the high content of polyunsaturated fatty a cid, fish flesh and fish oil are beneficial in reducing the serum cholesterol. In addition to that, the special type of fatty acid, omega -3 polyunsaturated fatty acid, is recognized as an important component to prevent a number of coronary heart diseases. Fish proteins contain all the essential amino acids in the required proportion and hence have a high nutritional value, which contribute to their high biological value. In fresh fi sh muscles, the water content is strongly bound to the proteins and cannot be easily removed even under higher pressure. For the present study, three different fish species, Clarias batrachus (E1), Mystus tengara (E2) and Puntius ticto (E3) were taken to study their protein content and analyze the electrophoretic protein banding pattern for both fresh and smoked dried conditions. Pr otein extract was made from the muscle tissue of the fishes taken. The protein content was measured by Lowry’s method using BSA protein as standard. The optical density was measu red at 660nm. The electrophoretic protein banding patterns were determined using SDS-PAGE gel electrophoresis. The results showed that the total protein concentration of samples for fresh condition E1F, E2F and E3F was found to be 7.15±0.247 mg/ml, 7.20±0.224 mg/ml and 4.98±0.283 mg/ml respectively and for smoked dried condition E1D, E2D and E3D was 8.48±0.273 mg/ml, 8.31±0.222 mg/ml and 5.81±0.335 mg/ml respectively. The SDS-PAGE electrophoresis showed significant increase in the protein bands of three types of smoked dried fish samples when compared to fresh ones. Therefore, the percentage of protein content in selected smoked dried fishes was found more.

A Comparative Study on Total Muscle Protein Content of Anabas testudineus, Labeo gonius, Labeo rohita and Heteropneustes fossilis and to analyze their Electrophoretic Banding Pattern using SDS-PAGE

India is undergoing nutrition transition and is facing the dual burden of malnutrition, problem of under-nutrition and malnutrition deficiencies. Fish is one such food that can solve the problem. Fresh fish flesh provides an excellent source of protein for human diet, which is relatively of digestibility, biological and growth promoting value for human consumption. The present study is aimed to determine the total muscle protein content of freshly killed fishes belonging to different species (Anabas testudineus [E1], Labeo gonius [E2], Labeo rohita [E3] and Heteropneustes fossilis [E4]) and also to analyze the electrophoretic banding pattern of muscle protein from the above species through SDS - PAGE gel electrophoresis. Electrophoresis can be used to separate and visualize proteins. In SDS -PAGE, proteins are separated based on size. When protein samples are applied to such gels, it is usually necessary to know the protein content or concentration of the sa mple. The total muscle protein estimation was done by Lowry’s method using BSA protein as standard. The optical densit y was measured at 660 nm. The results showed that the total protein concentration of sample E1, E2, E3 and E4 was found to be 8.31±0.314 mg/ml, 7.65±0.333 mg/ml, 6.98±0.315 mg/ml and 8.98±0.483 mg/ml respectively. The SDS-PAGE electrophoresis done in case of different fish species showed variation in the banding patterns, in which E1 and E4 showed maximum number of bands as compared to E2 and E3. Fishes belonging to the gro up of catfishes and perches were found to contain more amount of protein as compared to Indian Major Carps and Minor Carps. Therefore, fishes play a vital role as it is an important and cheaper source of quality animal proteins.

Chromatography at -30 °C for Reduced Back-Exchange, Reduced Carryover, and Improved Dynamic Range for Hydrogen-Deuterium Exchange Mass Spectrometry.

For hydrogen–deuterium exchange mass spectrometry (HDX-MS) to have an increased role in quality control of biopharmaceuticals, H for D back-exchange occurring during protein analyses should be minimized to promote greater reproducibility. Standard HDX-MS analysis systems that digest proteins and separate peptides at pH 2.7 and 0 °C can lose >30% of the deuterium marker within 15 min of sample injection. This report describes the architecture and performance of a dual-enzyme, HDX-MS instrument that conducts liquid chromatography (LC) separations at subzero temperature, thereby reducing back-exchange and supporting longer LC separations with improved chromatographic resolution. LC separations of perdeuterated, fully reduced, iodoacetamide-treated BSA protein digest standard peptides were performed at 0, −10, −20, and −30 °C in ethylene glycol (EG)/H2O mixtures. Analyses conducted at −20 and −30 °C produced similar results. After subtracting for deuterium retained in arginine side chains, the average peptide eluted during a 40 min gradient contained ≈16% more deuterium than peptides eluted with a conventional 8 min gradient at 0 °C. A subset of peptides exhibited ≈26% more deuterium. Although chromatographic peaks shift with EG concentration and temperature, the apparatus elutes unbroadened LC peaks. Electrospray ion intensity does not decline with increasing EG fraction. To minimize bias from sample carryover, the fluidic circuits allow flush and backflush cleaning of all enzyme and LC columns. The system can perform LC separations and clean enzyme columns simultaneously. Temperature zones are controlled ±0.058 °C. The potential of increased sensitivity by mixing acetonitrile with the analytical column effluent was also examined.

A monoclonal antibody for identifying capsaicin congeners in illegal cooking oil and its applications

In this work, we studied the preparation of a high-affinity antibody and its immunochromatographic applications to simultaneously identify capsaicin(LJJ), dihydrocapsaicin(HLJ), nordihydrocapsaicin, homodihydrocapsaicin, and other congeners in illegal cooking oil. We used dihydrocapsaicin hapten-conjugated carrier protein BSA as the immunogen according to the formaldehyde method, and conjugated capsaicin and OVA as the coated detection antigen according to the formaldehyde method. We subsequently screened and cloned a hybridoma cell line 2B3 with the highest affinity, which could stably secrete monoclonal antibodies against compounds in the capsaicin family. We then established a capsaicin indirect ELISA standard curve, which was fitted using the linear regression equation R = 0.9987, curve y = −2.3x + 0.2, and IC50 = 0.2 ng/mL. The cross-reaction rate for capsaicin was 100%, 116% for dihydrocapsaicin, 88% for homodihydrocapsaicin, and 94% for nordihydrocapsaicin. In the second application, we established a simple and accurate sample pretreatment method and a quantum dot-labeled test strip to quickly and quantitatively detect capsaicin family compounds in illegal cooking oil in 8 min. The average recovery rates for each spiked concentration were between 75% and 107.8%, and the coefficient of variation values for each spiked concentration were less than 15%. The high-affinity antibody we identified could simultaneously identify capsaicin, dihydrocapsaicin, nordihydrocapsaicin, homodihydrocapsaicin, and other congeners in illegal cooking oil, and the antibody could be quickly and accurately applied for the qualitative and quantitative detection of capsaicin family residues in illegal cooking oil.

Water Treatment Using High Performance Antifouling Ultrafiltration Polyether Sulfone Membranes Incorporated with Activated Carbon

Membrane fouling is a continued critical challenge for ultrafiltration membranes performance. In this work, polyether sulfone (PES) ultrafiltration (UF) membranes were fabricated via phase-inversion method by incorporating varying concentrations of APTMS modified activated carbon (mAC). The mAC was thoroughly characterized and the fabricated membranes were studied for their surface morphology, functional groups, contact angle, water retention, swelling (%) porosity, and water flux. The hydrophilicity of mAC membranes also resulted in lower contact angle and higher values of porosity, roughness, water retention as well as water flux. Also, the membranes incorporated with mAC exhibited antibacterial performance against model test strains of gram-negative Ecoil and gram-positive S. aureus. The antifouling studies based on bovine serum albumin protein (BSA) solution filtration showed that mAC membranes have better BSA flux. The higher flux and antifouling characteristics of the mAC membranes were attributed to the electrostatic repulsion of the BSA protein from the unique functional properties of AC and network structure of APTMS. The novel mAC ultrafiltration membranes developed and studied in present work can provide higher flux and less BSA rejection thus can find antifouling applications for the isolation and concentration of proteins and macromolecules.

Application of dextran to manipulate formation mechanism, morphology, and performance of ultrafiltration membranes

In this study, dextran polysaccharide was used as a hydrophilic non-solvent additive at different molecular weights and concentrations to prepare novel flat sheet PES membranes through non-solvent induced phase separation process. Formation mechanisms of the PES membranes were assessed thermodynamically and kinetically to verify the influence of dextran polysaccharide on evolving porous media. The obtained results revealed that, in the presence of dextran, the thermodynamic instability of the dope solutions could be remarkably enhanced, leading to a rapid instantaneous demixing during the phase inversion process. Morphologically, the long channel-like macrovoids of the sublayer were also transformed to a disordered structure and concave shapes were emerged on the membrane surface at high concentrations of dextran polysaccharide. Based on the obtained results, not only significant enhancements were achieved in membrane fluxes, but also BSA protein rejections and antifouling properties were improved by increasing the dextran concentration at either molecular weight. Accordingly, the experimental results indicated that the dextran polysaccharide could be employed in practice to achieve scalable high-quality UF membranes through simple NIPS method.

Integrated Approach to Interaction Studies of Pyrene Derivatives with Bovine Serum Albumin: Insights from Theory and Experiment.

This work aimed to investigate the interaction of bovine serum albumin with newly synthesized potent new pyrene derivatives (PS1 and PS2), which might prove useful to have a better antibacterial character as found for similar compounds in the previous report [Low et al. Bioconjugate Chemistry2014, 12, 2269−2284]. However, to date, binding studies with plasma protein are still unknown. Steady-state fluorescence spectroscopy and lifetime fluorescence studies show that the static interaction binding mode and binding constants of PS1 and PS2 are 7.39 and 7.81 [Kb × 105 (M–1)], respectively. The experimental results suggest that hydrophobic forces play a crucial role in interacting pyrene derivatives with BSA protein. To verify this, molecular docking and molecular dynamics simulations were performed to predict the nature of the interaction and the dynamic behavior of the two compounds in the BSA complex, PS1 and PS2, under physiological conditions of pH = 7.1. In addition, the free energies of binding for the BSA-PS1 and BSA-PS2 complexes were estimated at 300 K based on the molecular mechanics of the Poisson–Boltzmann surface (MMPBSA) with the Gromacs package. PS2 was found to have a higher binding affinity than PS1. To determine the behavior of the orbital transitions in the ground state geometry, we found that both compounds have similar orbital transitions from HOMO–LUMO via π → π* and HOMO–1–LUMO+1 via n → π*, which was included in the FMO analysis. A cytotoxicity study was performed to determine the toxicity of the compounds. Based on the MD study, the stability of the compounds with BSA and the dynamic binding modes were further revealed, as well as the nature of the binding force components involved and the important residues involved in the binding process. From the binding energy analysis, it can be assumed that PS2 may be more active than PS1.

Electrochemiluminescent detection of epilepsy biomarker miR-134 using a metal complex light switch

The detection of a key biomarker in epilepsy, miR-134, using an environmentally sensitive electrochemiluminescent luminophore, [Ru(DPPZ)2 PIC]2+, is reported, DPPZ is dipyrido[3,2-a:2′,3′-c]phenazine) and PIC is (2,2′-bipyridyl)-2(4-carboxy phenyl) imidazo [4,5][1,10] phenanthroline. A thiolated capture strand is first labelled with [Ru(DPPZ)2 PIC]2+ and then adsorbed onto a gold electrode. No significant electrochemiluminescence, ECL, is observed for immobilised Ru-labelled capture strands which is consistent with the light-switch dye being exposed to the aqueous solution. In sharp contrast, binding of the target turns on ECL. The ECL intensity, IECL, depends on the number of adenine “spacer” bases between the end of the capture sequence and the dye. The ECL intensity for the optimised system increases linearly with increasing miR-134 concentration from 100 nM to approximately 20 μM. Single and double base mismatches produce IECL that are only approximately 30% and 8% respectively of that observed for the fully complementary target reflecting differences in their association constants. Significantly, the presence of BSA protein causes IECL to increase by less 5% in either the single or duplex circumstances. Finally, the ability of the sensor to quantify miR-134 in unprocessed plasma samples from healthy volunteers and people with epilepsy is reported.

Synthesis and characterization of copper complexes of phenylpiperazine ring-based ligands and evaluation of their antimicrobial, BSA binding, computational, and molecular docking studies

This paper describes the synthesise of copper complexes of phenylpiperazine ring-based ligands and characterization via physical and spectroscopic methods. Structure of complexes has been proposed on the basis of UV-vis, IR and Mass fragmentation pattern and additionally supported by electrochemical and thermogravimetric analysis. Low molar conductance value of metal complexes in water and DMSO suggest non-ionic nature of complexes which is in agreement of proposed structure. TGA curve, where loss of coordinated solvent molecules starts early followed by loss of ligand itself also support the proposed structures. Percentage ash content analysis also indicate that only one copper metal is binding to the ligands reported here. Antibacterial activity of metal complexes has been performed by agar well diffusion method and indicated these metal complexes possess higher activity than the corresponding ligands. Binding interaction of these complexes were studied with BSA protein by UV-vis spectroscopic methods and binding constant was calculated which indicated that the complexes are having moderate affinity. Some complexes were also geometrically optimized to lowest energy ground state by using DFT calculations. Docking study of these optimized structures with BSA protein revealed these metal complexes exhibit hydrophobic interaction owing to the aromatic bulk in the ligand.

3D Natural Mesoporous Biosilica-Embedded Polysulfone Made Ultrafiltration Membranes for Application in Separation Technology.

Diatoms are the most abundant photosynthetic microalgae found in all aquatic habitats. In the extant study, the spent biomass (after lipid extraction) of the centric marine diatom Thalassiosira lundiana CSIRCSMCRI 001 was subjected to acid digestion for the extraction of micro composite inorganic biosilica. Then, the resulting three-dimensional mesoporous biosilica material (diatomite) was used as a filler in polysulfone (PSF) membrane preparation by phase inversion. The fabricated PSF/diatomite composite membranes were characterized by SEM-EDX, TGA, and ATR-IR, and their performances were evaluated. The number of pores and pore size were increased on the membrane surface with increased diatomite in the composite membranes as compared to the control. The diatomite composite membranes had high hydrophilicity and thermal stability, lower surface roughness, and excellent water permeability. Membranes with high % diatomite, i.e., PSF/Dia0.5, had a maximum water flux of 806.8 LMH (Liter/m2/h) at 20 psi operating pressure. High-diatomite content membranes also exhibited the highest rejection of BSA protein (98.5%) and rhodamine 6G (94.8%). Similarly, in biomedical rejection tests, the PSF/Dia0.5 membrane exhibited a maximum rejection of ampicillin (75.84%) and neomycin (85.88%) at 20 Psi pressure. In conclusion, the mesoporous inorganic biosilica material was extracted from spent biomass of diatom and successfully used in filtration techniques. The results of this study could enhance the application of natural biogenic porous silica materials in wastewater treatment for water recycling.

The myrosinase-glucosinolate system to generate neoglycoproteins: A case study targeting mannose binding lectins

A convenient strategy for a ‘one-pot’ synthesis of neoglycoproteins (NGP) was developed using the myrosinase-glucosinolate couple, a natural enzyme-substrate system. This enzymatic reaction allowed us to generate an isothiocyanate in situ which then reacted with the lysine residues of bovine serum albumin protein (BSA) to produce multivalent neoglycoproteins. Using two models, glucomoringin which is a natural glucosinolate bearing a l-rhamnose unit, and an artificial glucosinolate specifically designed for mannose type lectins, an average of up to 17.8 and 28.7 carbohydrate residues could be respectively grafted onto the BSA protein. This process is comparable to commercial approaches using BSA-ManC without the disadvantage of handling harmful chemical reagents. Lectin binding screening (GLYcoPROFILE®) showed that among all NGPs synthesized, BSA-Man 16 gave similar and in some cases better affinities in comparison with commercial BSA-Manc towards various mannose-specific lectins.

Controlled synthesis of PEGylated polyelectrolyte nanogels as efficient protein carriers

Designing rational carriers for protein encapsulation and delivery is of great interest in a wide range of applications. Herein, we develop a type of PEGylated polyelectrolyte nanogel that enables efficient protein loading, protection and intracellular delivery. Our design relies on a one pot process involving cooperative electrostatic assembly and polymerization, which constructs polyion complex (PIC) micelles containing cross-linked cationic PDMAEMA network associated with anionic PAA. Further removing PAA chains leads to core–shell nanogels with a cationic network surrounded by poly (ethylene glycol) (PEG) blocks. The established strategy allows to fabricate well-defined nanogels with regulated size and swelling ability depending on pH, salt concentration and cross-link degree. More notably, the abundant positive charges and the thermo-response of PDMAEMA network realize sufficient encapsulation and protection of BSA proteins, while the PEG blocks endow appreciable biocompatibility and successful intracellular protein delivery. Our study establishes a facile and robust approach for preparing core–shell polyelectrolyte nanogels with regulated size and properties, as well as prominent capabilities for protein encapsulation and delivery.

Sustainable Modification of Polyethersulfone Membrane with Poly(Maleic Anhydride-Co-Glycerol) as Novel Copolymer

This work presented an endeavour to fabricate sustainable and eco-friendly polyethersulfone (PES) ultrafiltration membranes. A novel and graft copolymer (Poly(Maleic Anhydride-Co-Glycerol)) (PMG) have been synthesized via a facile and rapid route to impart their hydrophilic features onto the final PES membrane. A series of characterization tools, for both nanoadditives and nanocomposite membranes, have been harnessed to confirm their successful fabrication processes. These include Fourier Transform Infrared Spectroscopy (FT-IR), scanning electron microscopy (SEM), Atomic Force Microscopy (AFM), and contact angle measurements (CA). Results disclosed the successful synthesis of PMG nanoparticles that manifested a smooth homogenous surface with an average molecular size of 88.07 nm. The nanocomposite membrane structure has witnessed a gradual development upon each increment in the nanoparticle content ratio along with relatively thicker pore walls. The size and shape of figure-like micropores exhibited critical visible structural changes following the nanoadditive incorporation into the PES polymeric matrix. For the nanocomposite membrane, the SEM imaging indicated that a thicker active layer and less finger-like micropores were formed at higher PMG NP content within the membrane matrix. Hydrophilicity measurements disclosed a reversible correlation with the NP content where the CA angle value was at a minimum at the higher PMG loading content. Compared to the pristine membrane, a considerable enhancement in the performance of the modified membranes was witnessed. The membrane prepared using 2.5 g PMGNPs showcased six times higher pure water flux than neat PES membrane and maintained the highest retention (98%) against BSA protein solution. Additionally, the nanocomposite revealed promising antifouling and self-cleaning characteristics.

Alum Adjuvant and Built-in TLR7 Agonist Synergistically Enhance Anti-MUC1 Immune Responses for Cancer Vaccine.

The tumor-associated antigen mucin 1 (MUC1) is an attractive target of antitumor vaccine, but its weak immunogenicity is a big challenge for the development of vaccine. In order to enhance immune responses against MUC1, herein, we conjugated small molecular toll-like receptor 7 agonist (TLR7a) to carrier protein BSA via MUC1 glycopeptide to form a three-component conjugate (BSA-MUC1-TLR7a). Furthermore, we combined the three-component conjugate with Alum adjuvant to explore their synergistic effects. The immunological studies indicated that Alum adjuvant and built-in TLR7a synergistically enhanced anti-MUC1 antibody responses and showed Th1-biased immune responses. Meanwhile, antibodies elicited by the vaccine candidate effectively recognized tumor cells and induced complement-dependent cytotoxicity. In addition, Alum adjuvant and built-in TLR7a synergistically enhanced MUC1 glycopeptide-specific memory CD8+ T-cell immune responses. More importantly, the vaccine with the binary adjuvant can significantly inhibit tumor growth and prolong the survival time of mice in the tumor challenge experiment. This novel vaccine construct provides an effective strategy to develop antitumor vaccines.