Characterisation and separation of infectious bursal disease virus-like particles using aqueous two-phase systems

Infectious bursal disease(IBD)causes considerable economic losses in the commercial poultry industry worldwide.The principal way to control IBD virus(IBDV),the causative agent of IBD,is still through vaccination programs.Virus-like particles(VLPs)are recognised as a safe and potent recombinant vaccine platform.This research work explores the characterisation and separation of infectious bursal disease virus-like particles(IBD-VLPs)from crude feedstock.Various characteristics were studied with highperformance size-exclusion chromatography(HP-SEC),sodium dodecyl sulphate–polyacrylamide gel electrophoresis(SDS-PAGE)and transmission electron microscopy(TEM)analyses.Subsequently,the separation of IBD-VLPs using polyethylene glycol(PEG)/sodium citrate-based aqueous two-phase systems(ATPSs)was conducted and optimised.Moreover,a scale-up study of the best ATPS constituted of 15%PEG 6000,11%sodium citrate and 10%crude feedstock was performed to compare the separation performance of IBD-VLPs with and without centrifugation-assisted.The results indicated that the optimised ATPS with centrifugation-assisted for both 5 g and 50 g systems showed good recovery of IBDVLPs of>97%in the interphase between the PEG-rich top and salt-rich bottom phases.These optimised systems also showed high removal efficiencies of impurities of>95%.The results demonstrated that aqueous two-phase extraction could be a promising technology for efficient VLPs separation.

A breathing A4 paper by in situ growth of green metal-organic frameworks for air freshening and cleaning

Surface modification of natural cellulose fibers with nanomaterials is an effective strategy for producing functional textiles for multiple applications.A4-sized printing paper is a commonly used,cheap,and easily acquirable office supply which is mainly made of cellulose fibers.Here,we report green and simple nanofabrication of A4 paper to endow it with high capability for fragrance encapsulation and sustained release,and strong adsorption to indoor air pollutants.The method utilizes the sugar molecule of cellulose for in-situ growth ofγ-cyclodextrin(γ-CD)metal-organic frameworks(MOFs)on A4 paper.The obtainedγ-CD-MOF/A4 nanocomposites have superior specific surface area and high porous structure.Theγ-CD-MOF/A4 nanocomposites can effectively encapsulate fragrant molecules through host-guest interaction.Theγ-CD-MOF/A4 nanocomposites also show strong absorption capability to formaldehyde and carbon dioxide through the formation of hydrogen bonding and chemical bonds.Theseγ-CD-MOF/A4nanocomposites combine the advantages of both A4 paper andγ-CD-MOF,which can be used in indoor air freshening and cleaning.

UV/Vis-based process analytical technology to improve monoclonal antibody and host cell protein separation

Process analytical technology(PAT) is gaining more interest in the biomanufacturing industry because of its potential to improve operational control and compliance through real-time quality assurance.Currently, biopharmaceutical producers mainly monitor chromatographic processes with ultraviolet/visible(UV/Vis) absorbance. However, this measurement has a very limited correlation with purity and quantity. The current study aims to determine the concentration of monoclonal antibody(mAb) and host cell proteins(HCPs) using a build-in UV/Vis monitoring during Protein A affinity chromatography and to optimize the separation conditions for high purity of mAb and minimizing the HCPs content. The eluate was analyzed through in-line UV/Vis at 280 and 410 nm, representing mAb and HCPs concentration,respectively. Each 0.1 column volume(CV) fraction of UV/Vis chromatogram peak area were calculated,and different separation conditions were then compared. The optimum conditions of mAb separation were found as 12 CV loading, elution at pH 3.5, and starting the collection at 0.5 CV point, resulting in high m Ab recovery of 95.92% and additional removal of 49.98% of HCP comparing with whole elution pool. This study concluded that UV/Vis-based in-line monitoring at 280 and 410 nm showed a high potential to optimize and real-time control Protein A affinity chromatography for mAb purification from HCPs.

Biomanufacturing ofγ-linolenic acid-enriched galactosyldiacylglycerols:Challenges in microalgae and potential in oleaginous yeasts

γ-Linolenic acid-enriched galactosyldiacylglycerols(GDGs-GLA),as the natural form ofγ-linolenic acid in microalgae,have a range of functional activities,including anti-inflammatory,antioxidant,and anti-allergic properties.The low abundance of microalgae and the structural stereoselectivity complexity impede microalgae extraction or chemical synthesis,resulting in a lack of supply of GDGs-GLA with a growing demand.At present,there is a growing interest in engineering oleaginous yeasts for mass production of GDGs-GLA based on their ability to utilize a variety of hydrophobic substrates and a high metabolic flux toward fatty acid and lipid(triacylglycerol,TAG)production.Here,we first introduce the GDGs-GLA biosynthetic pathway in microalgae and challenges in the engineering of the native host.Subsequently,we describe in detail the applications of oleaginous yeasts with Yarrowia lipolytica as the representative for GDGs-GLA biosynthesis,including the development of synthetic biology parts,gene editing tools,and metabolic engineering of lipid biosynthesis.Finally,we discuss the development trend of GDGs-GLA biosynthesis in Y.lipolytica.

Local high-density distributions of phospholipids induced by the nucleation and growth of smectic liquid crystals at the interface

Amphiphilic molecules adsorbed at the interface could control the orientation of liquid crystals(LCs)while LCs in turn could influence the distributions of amphiphilic molecules.The studies on the interactions between liquid crystals and amphiphilic molecules at the interface are important for the development of molecular sensors.In this paper,we demonstrate that the development of smectic LC ordering from isotropic at the LC/water interface could induce local high-density distributions of amphiphilic phospholipids.Mixtures of liquid crystals and phospholipids in chloroform are first emulsified in water.By fluorescently labeling the phospholipids adsorbed at the interface,their distributions are visualized under fluorescent confocal microscope.Interestingly,local high-density distributions of phospholipids showing a high fluorescent intensity are observed on the surface of LC droplets.Investigations on the correlation between phospholipid density,surface tension and smectic LC ordering suggest that when domains of smectic LC layers nucleate and grow from isotropic at the LC/water interface as chloroform slowly evaporates at room temperature,phospholipids transition from liquid-expanded to liquid-condensed phases in response to the smectic ordering,which induces a higher surface tension at the interface.The results will provide an important insight into the interactions between liquid crystals and amphiphilic molecules at the interface.

De Novo Biosynthesis of Vindoline and Catharanthine in Saccharomyces cerevisiae

Vinblastine has been used clinically as one of the most potent therapeutics for the treatment of several types of cancer.However,the traditional plant extraction method suffers from unreliable supply,low abundance,and extremely high cost.Here,we use synthetic biology approach to engineer Saccharomyces cerevisiae for de novo biosynthesis of vindoline and catharanthine,which can be coupled chemically or biologically to vinblastine.On the basis of a platform strain with sufficient supply of precursors and cofactors for biosynthesis,we reconstituted,debottlenecked,and optimized the biosynthetic pathways for the production of vindoline and catharanthine.The vindoline biosynthetic pathway represents one of the most complicated pathways ever reconstituted in microbial cell factories.Using shake flask fermentation,our engineered yeast strains were able to produce catharanthine and vindoline at a titer of 527.1 and 305.1μg·liter^(−1),respectively,without accumulating detectable amount of pathway intermediates.This study establishes a representative example for the production of valuable plant natural products in yeast.

Tuning the Stability of the Polyplex Nanovesicles of Oligonucleotides via a Zinc(Ⅱ)-Coordinative Strategy

Oligonucleotide therapeutics have great potential to target the currently undruggable genes and to generate entirely new therapeutic paradigms in multiple types of disease,thus having attracted much attention in recent years.However,their applications are greatly hindered by a lack of safe and efficient oligonucleotide-delivery vectors.Polyplex nanovesicles formed from oligonucleotides and the cationic block have shown exceptional features for the delivery of therapeutic oligonucleotides and other biopharmaceuticals.Nevertheless,these polyplex nanovesicles are deeply fraught with difficulty in tolerating physiological ionic strength.Inspired by the high binding ability between the dipicolylamine(DPA)/zinc(Ⅱ)complex and the phosphodiester moieties of oligonucleotides,herein,we designed a coordinative cationic block to solve the intrinsic stability dilemma.Moreover,we found the stability of the resulted polyplex nanovesicles could be easily tuned by the content of coordinated zinc ions.In vitro cellular studies implied that the prepared zinc(Ⅱ)-coordinative polyplex nanovesicles preferred to retain in the lysosomes upon internalization,making them ideal delivery candidates for the lysosome-targeting oligonucleotide therapeutics.

Porous ultrathin-shell microcapsules designed by microfluidics for selective permeation and stimuli-triggered release

Microcapsules are versatile delivery vehicles and widely used in various areas.Generally,microcapsules with solid shells lack selective permeation and only exhibit a simple release mode.Here,we use ultrathin-shell water-in-oil-in-water double emulsions as templates and design porous ultrathin-shell microcapsules for selective permeation and multiple stimuli-triggered release.After preparation of double emulsions by microfluidic devices,negatively charged shellac nanoparticles dispersed in the inner water core electrostatically complex with positively charged telechelicα,ω-diamino functionalized polydimethylsiloxane polymers dissolved in the middle oil shell at the water/oil interface,thus forming a porous shell of shellac nanoparticles cross-linked by telechelic polymers.Subsequently,the double emulsions become porous microcapsules upon evaporation of the middle oil phase.The porous ultrathin-shell microcapsules exhibit excellent properties,including tunable size,selective permeation and stimuli-triggered release.Small molecules or particles can diffuse across the shell,while large molecules or particles are encapsulated in the core,and release of the encapsulated cargos can be triggered by osmotic shock or a pH change.Due to their unique performance,porous ultrathin-shell microcapsules present promising platforms for various applications,such as drug delivery.

“One-for-All”approach:a black technology for nanomedicine development?

Cancer nanomedicines require different,even opposite,properties to voyage the cascade drug delivery process involving a series of biological barriers.Currentlyapproved nanomedicines can only alleviate adverse effects but cannot improve patient survival because they fail to meet all the requirements.Therefore,nanocarriers with synchronized functions are highly requisite to capacitate efficient drug delivery and enhanced therapeutic efficacies.This perspective article summarizes recent advances in the two main strategies for nanomedicine design,the All-in-One approach(integration of all the functions in one system)and the One-for-All approach(one functional group with proper affinity enables all the functions),and presents our views on future nanomedicine development.

Biomedical polymers: synthesis, properties, and applications

Biomedical polymers have been extensively developed for promising applications in a lot of biomedical fields, such as therapeutic medicine delivery, disease detection and diagnosis, biosensing, regenerative medicine, and disease treatment. In this review, we summarize the most recent advances in the synthesis and application of biomedical polymers, and discuss the comprehensive understanding of their property-function relationship for corresponding biomedical applications. In particular, a few burgeoning bioactive polymers, such as peptide/biomembrane/microorganism/cell-based biomedical polymers, are also introduced and highlighted as the emerging biomaterials for cancer precision therapy. Furthermore, the foreseeable challenges and outlook of the development of more efficient, healthier and safer biomedical polymers are discussed. We wish this systemic and comprehensive review on highlighting frontier progress of biomedical polymers could inspire and promote new breakthrough in fundamental research and clinical translation.

Efficient acetylene/carbon dioxide separation with excellent dynamic capacity and low regeneration energy by anion-pillared hybrid materials

Adsorptive separation of acetylene/carbon dioxide mixtures by porous materials is an important and challenging task due to their similar sizes and physical properties.Here,remarkable acetylene/carbon dioxide separation featuring a high dynamic breakthrough capacity for acetylene(4.3 mmol·g^(–1))as well as an ultralow acetylene regeneration energy(29.5 kJ·mol^(–1))was achieved with the novel TiF_(6)^(2–)-pillared material ZU-100(TIFSIX-bpy-Ni).Construction of a pore structure with abundant TiF_(6)^(2–)anion sites and pores with appropriate sizes enabled formation of acetylene clusters through hydrogen bonds and intermolecular interactions,which afforded a high acetylene capacity(8.3 mmol·g^(–1))and high acetylene/carbon dioxide uptake ratio(1.9)at 298 K and 1 bar.Moreover,the NbO_(5)^(2–)anion-pillared material ZU-61 investigated for separation of acetylene/carbon dioxide.In addition,breakthrough experiments were also conducted to further confirm the excellent dynamic acetylene/carbon dioxide separation performance of ZU-100.