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The treatment of bladder cancers has improved with new immunotherapy such as PD-L1. However, not all bladder cancers respond to PD-L1 immunotherapy which is why new targets are being assessed. Melanoma-associated antigen gene A (MAGE-A) family proteins are expressed in a variety of tumors, with each MAGE-A protein having unique roles in cancer pathogenesis. One advantage of targeting MAGE-A family members is the lack of expression in normal tissues which makes them well-suited for targeted cancer immunotherapy. The challenge with screening the MAGE-A family is to find a specific antibody since the 12-member family has over 60% sequence in homology. In this study, we evaluate multiple MAGE-A3 and MAGE-A4 antibodies using CytoSections, a reproducible alternative to control tissue with an expression of target biomarkers. A series of antibodies specific to each MAGE-A3 and MAGE-A4 protein were discovered and used to screen twenty-five bladder cancer tissues. The results showed that MAGE-A3 was present in 9 of the 25 bladder cancers, while MAGE-A4 was present in 10 of the 25 bladder cancers evaluated; in the meantime, 7 bladder cancers were positive for both targets after double immunofluorescence staining with MAGE-A3 or A4 specific antibodies. The data presented here could be an important development in treatment protocols for pre-screening patients who are at risk. Our findings show that MAGE-A3 and MAGE-A4 can be both present in bladder cancer, suggesting that targeting both genes may be necessary for the success of immunotherapy treatment. Citation Format: Bailey Gilmore, Rachel Gonzalez, Aubrey Su, Dehe Kong, Eden Zewdu, Jina Yom, Tianli Qu, Zhaoying Guo, Xiaomin Hu, Qi Ren, Ranran Zhang, Eric Christenson, Yan Ma, Dezhong Yin, Patrick Yin, Wei Fu, Xuan Liu, Krishnan Allampallam. Colocalization of MAGE-A3 and MAGE-A4 in bladder cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 999.

Tet-On is a powerful inducible system and a classical tool to regulate gene expression in mammalian cells. It has also been applied to regulate Pol III-driven transcription, such as shRNA or gRNA driven by a U6 or H1 promoter. However, all of the current versions of Tet-On shRNA vectors are based on H1-2O2 or U6-2O2 promoters, which are only compatible with first-generation tetracycline repressor TetR. In addition, these promoters have the problem of driving downstream transcription without the binding of the Tet regulatory protein. Here, we developed a new system that is built upon tetracycline activator protein, Tet-On 3G, combined with a new structure of Tet responsive promoter H1-4O4, which tightly regulates the downstream transcription of gRNA or shRNA. The responsiveness of our system to Doxycycline regulation is dramatically improved compared with the current versions. The new Tet-On system is further optimized into a compact structure to be compatible with the lentivirus package (All-In-One Lenti-Tet-On system), which still keeps the leaky expression at an undetectable level. Combined with all these features, the new generation of the Tet-On system offers broad applications in gene knocking down and genomic editing. Citation Format: Lipeng Wu, Hua Su, Justin Fellows, Mao Fu, Julian Heller, Brian Park, Dezhong Yin. Development of a new All-In-One inducible lentiviral shRNA/gRNA Vector. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3727.

In this paper, BiOBr/BiOCl heterostructure microspheres are prepared successfully via a simple solvothermal way. Research shows that BiOBr/BiOCl microspheres exhibit significantly much higher photocatalytic performance than pure BiOBr or BiOCl. The optimum photodegradation rate of BiOBr/BiOCl for rhodamine B (RhB) is 0.0290 min−1, which is approximately 4.5 times as high as pure BiOBr (k = 0.0065 min−1) and 8.8 times as high as pure BiOCl (k = 0.0033 min−1) under visible light. For this new photocatalyst, the enhanced photoactivity is presumably attributed to the formation of heterojunction which improves the separation of photoinduced electrons and holes to a great extent. Mechanism investigation reveals that O.− plays significant roles during the photocatalysis process.

Neurological diseases and disorders are leading causes of death and disability worldwide. Many of these pathologies are associated with high levels of neuroinflammation and irreparable tissue damage. As the global burden of these pathologies continues to rise there is a significant need for the development of novel therapeutics. Due to their multipotent properties, stem cells have broad applications for tissue repair; additionally, stem cells have been shown to possess both immunomodulatory and neuroprotective properties. It is now believed that paracrine factors, such as extracellular vesicles (EVs), play a critical role in the functionality associated with stem cells. The diverse biological cargo contained within EVs are proposed to mediate these effects and, to date, the reparative and regenerative effects of stem cell EVs have been demonstrated in a wide range of cell types. While a high potential for their therapeutic use exists, there is a gap of knowledge surrounding their characterization, mechanisms of action, and how they may regulate cells of the CNS. Here, we report the isolation, characterization, and functional assessment of EVs from two sources of human stem cells, mesenchymal stem cells and induced pluripotent stem cells. We demonstrate the ability of these EVs to enhance the processes of cellular migration and angiogenesis, which are critical for both normal cellular development as well as cellular repair. Furthermore, we investigate their reparative effects on damaged cells, specifically those with relevance to the central nervous system. Collectively, our data highlight the similarities and differences among these EV populations and support the view that stem cells EV can be used to repair or partially reverse cellular damage. Graphical Abstract Stem cell-derived Extracellular Vesicles (EVs) for repair of damaged cells. EVs isolated from human induced pluripotent stem cells and mesenchymal stem cells contribute to the partial reversal of phenotypes induced by different sources of cellular damage.

Hepatocellular carcinoma (HCC) is one of the most prevalent tumors worldwide. Hydroxysteroid 17-beta dehydrogenase 13 (HSD17B13), which was newly identified as a liver lipid droplet associated protein, was recently found to be down-regulated in HCC. However, the effects of HSD17B13 on the underlying mechanisms of HCC have not yet been fully explored. For this purpose, HSD17B13 gene was knockdown with CRISPER/Cas9 technique in several HCC cell lines. HSD17B13 expression was detected by Flow cytometry and Western blotting with recombinant rabbit monoclonal antibodies (clone OTIR3G2 and OTIR5C10) against HSD17B13 which were screened for use in immunohistochemistry, western blot, and ELISA application. Overexpressed HSD17B13 induces hepatic cell line G1 capture and increases several G1 arrest-related protein expression, including p21, p27, MMP2 and MMP3. Then the proliferation and cell cycle were suppressed. HSD17B13 gene knockdown will reverse the suppression. These data indicated that HSD17B13 play important roles in the progression of HCC lesions. HSD17B13 might be a potential immune-oncology marker for HCC. Citation Format: Tianli Qu, Lipeng Wu, Jina Yom, Zhaoying Guo, Xiaomin Hu, Qi Ren, Qian Niu, Ruei-Shiuan Lin, Dezhong Yin, Xuan Liu, Fu Wei. Overexpression of HSD17B13 induced G1 arrest in hepatic cell lines detected by anti-HSD17B13 recombinant rabbit monoclonal antibody [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3695.

Melanoma-associated antigen gene A (MAGEA) family proteins are expressed in a variety of tumors with each MAGEA protein having unique roles in cancer pathogenesis. The MAGEA members lack of expression in normal tissue and their role in cancer make them well suited for targeted cancer immunotherapy. Thus, knowing which MAGEA protein expression exists in a tumor is important. However, the MAGEA family shares sequence similarity that makes it difficult to find antibodies that are specific to just one family member. It is also challenging to source tissue generally with HIPAA regulation and even more so to get tissue representation of all 12 MAGEA family members. Here we present CytoSections as an alternative to patient control tissues. CytoSections are formalin fixed, paraffin embedded (FFPE) section of over-expression cell pellets. These cells were transfected with expression plasmids coding for genes of individual MAGES family. In this study, CytoSections are used to screen antibodies to all 12-member MAGEA family of proteins. The MAGEA family members were initially shown positive by targeted protein expression in western and immunohistochemistry using DDK tag antibody. Then multiple MAGEA3, MAGEA4, MAGEA9 antibodies were assessed by IHC to determine their specificity to their intended target. Using MAGEA family as a pilot project, we show that CytoSections is a verified, reproducible, and renewable alternative to human control tissues and serves as an ideal tool for antibody specificity assessment. Citation Format: Eden B. Zewdu, Rachel M. Gonzalez, Yan Ma, Derek Ling, Xiaomin Hu, Qi Ren, Ranran Zhang, Li-Hui Lei, Krishnan Allampallam, Dezhong Yin, Xuan Liu, Wei Fu. A renewable IHC control tool CytoSections࣪ for defining MAGEA3, MAGEA4, and MAGEA9 antibody specificity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2803.

Neurodegeneration is a hallmark of many diseases and disorders of the central nervous system (CNS). High levels of neuroinflammation are often associated with irreparable damage to CNS cells due to the dysregulation of signaling cascades that are unable to restore a homeostatic balance. Due to the inherent complexity of the CNS, development of CNS-related therapeutics has met limited success. While stem cell therapy has been evaluated in the context of CNS repair, the mechanisms responsible for their functional properties have not been clearly defined. In recent years, there has been growing interest in the use of stem cell extracellular vesicles (EVs) for the treatment of various CNS pathologies as these vesicles are believed to mediate many of the functional effects associated with their donor stem cells. The potency of stem cell EVs is believed to be largely driven by their biological cargo which includes various types of RNAs, proteins, and cytokines. In this review, we describe the characteristic properties of stem cell EVs and summarize their reported neuroprotective and immunomodulatory functions. A special emphasis is placed on the identification of specific biological cargo, including proteins and non-coding RNA molecules, that have been found to be associated with stem cell EVs. Collectively, this review highlights the potential of stem cell EVs as an alternative to traditional stem cell therapy for the repair of cellular damage associated with diverse CNS pathologies.

In order to meet the application of the flexible wings of the submersible, nanocomposite hydrogels(NC gels) was prepared. Preparation of polyglycidyl methacrylate (PGMA) microspheres and correspondingly NC gels were reported. PGMA microspheres were prepared and modified by N-Methyl-D-glucamine, followed by free radical polymerization of acrylamide in the presence of microspheres to construct nanocomposite hydrogel. FT-IR, XPS and DLS verified a successful introduction of hydroxyl groups during modification. The effects of the particle size and content of the microspheres on the swelling properties of the composite hydrogels were investigated. Hydrogen bonds between hydroxyl groups and polyacrylamide molecular chains play important roles to the swelling property of NC gels. The intermolecular interaction and the crosslinking density were enhanced by the hydrogen bonds, and resultantly, swelling ratio of NC gels decreases.

A new experiment based on phase inversion of Pickering emulsions was carried out in a physical chemistry course. The emulsions were stabilized by surfactant-modified SiO2 particles. As the concentration of surfactant increased, the emulsions changed from oil-in-water type (O/W) to water-in-oil type (W/O) type, and then reverted to be O/W type again. This double phase inversion of emulsions proved to be an ideal indicator for the adsorption of surfactant on particle surfaces. The students gained preliminary lab skills and improved their understanding of the basic concepts in colloid and interface chemistry. In addition, students were encouraged to work out a mechanism to explain the phase inversion; this practice helped strengthen and improve their reasoning abilities.

Microencapsulated phase change materials (MePCMs) based on swelling polymerization in Pickering emulsion were demonstrated. Monodisperse poly(glycidyl methacrylate-co-2-hydroxyethyl methacrylate) P(GMA-co-HEMA) particles were prepared by dispersion polymerization. The introduction of hydrophilic monomer HEMA endowed the obtained particles with suitable surface hydrophilicity for stabilizing Pickering emulsion. MePCMs with PGMA–polystyrene interpenetrating composite shell were formed when non-crosslinked particles were employed as stabilizer, while MePCMs with particles-embedded shell were prepared with crosslinked particles as Pickering stabilizer. Phase change property, thermal stability and thermal reliability of two kinds of MePCMs were investigated by TGA, FT-IR, DSC and cycling test. The temperature of 10% weight loss of MePCMs with interpenetrating shell was 11 °C higher than that of MePCMs with particles-embedded shell. After cycling test, the percentage of leached core materials from MePCMs with interpenetrating shell was approximately one-third of that from MePCMs with particles-embedded shell. The results showed that MePCMs with an integral shell presented better thermal stability, tightness and thermal reliability than MePCMs with particles-embedded shell. The research developed a simple process for MePCMs with excellent performance.

Fe 3 O 4 @SiO 2 @m-SiO 2 magnetic mesoporous (SmSMM) microspheres were synthesized by two steps Stober hydrolysis. The surface of the SmSMM microspheres were modified with γ-(2,3-epoxypropoxy)propytrimethoxysilane (KH560) and dendritic hyperbranched amine (DHA) to obtain SmSMM-DHA microspheres, which were used as carriers for the immobilization of penicillin G acylase (PGA). The diameter of SmSMM-DHA microspheres was around 500 nm and the specific saturation magnetization was 61.25 emu g −1 . The advantages of the as-prepared carries were large specific surface area and high amino content, the values were 323.1 m 2 g −1 and 2.1 mmol g −1 , respectively. The influences of the factors on amino content, immobilization rate and enzyme activity were investigated. The research results of PGA immobilized on SmSMM-DHA microspheres indicated that compared with free enzyme, the immobilized PGA showed excellent pH and thermo stability. Meanwhile, after being used for ten times, the enzyme activity retention rate was 94.5%. The designed immobilized enzyme shows potential application value in the synthesis of antibiotics.

A polymerized high internal phase emulsion (polyHIPE) was prepared using styrene, divinylbenzene and butyl acrylate as raw material and employed as stationary phase of thin layer chromatography (TLC). SEM, mercury intrusion porosimetry and FT-IR spectrum were employed to characterize the pore structure and chemical composition. To verify the feasibility as stationary phase of TLC, identification of plant extracts, Chinese herbs and traditional Chinese medicine were practiced on the prepared polyHIPE. Relative retardation factor (α), theoretical plate number (Nplate) and resolution (R) were used to evaluate the performance of TLC. Large difference in α value make it is feasible to optimize the chromatographic condition. The resolution R and Nplate indicates that the introduction of BA in polyHIPE facilitates the preparation and improves the performance for TLC separation. Our results show that polyHIPE monolith is a reusable stationary phase of TLC with high performance.

In this paper, BiOBr/BiOCl/CQDs heterostructure microspheres were successfully synthesized via a facile solvothermal method. Then, the structures, morphologies, optical properties and photocatalytic performances were investigated. This research showed that the BiOBr/BiOCl/CQDs microspheres exhibited significantly enhanced photocatalytic performance compared with BiOBr/BiOCl. In the photocatalysis process of rhodamine B (RhB) under visible light irradiation, the highest photodegradation rate (0.0609 min−1) would be obtained when the weight percentage of CQDs was appropriate, which was about 2.8 times higher than that of BiOBr/BiOCl (0.0217 min−1). In this photocatalytic system, the enhanced photoactivity was mainly attributed to the heterojunction interface among CQDs, BiOBr and BiOCl, and enhanced light harvesting for the appropriate CQD introduction. The radical trapping experiments revealed that O2˙−, e− and h+ were the main active species during the photocatalysis process.

Microcapsules of a phase change material synthesized by thermally sintering Pickering emulsion-based colloidosomes were demonstrated. The protocol included three steps: (1) monodispersive poly(glycidyl methacrylate) (PGMA) microspheres were prepared by dispersive polymerization and were endowed with a contact angle of 63.4° for oil-in-water Pickering stabilization by hydrolysis. (2) By phase separation during Pickering emulsion polymerization, microcapsules with a structure of a single PCM core and a PGMA armored polystyrene shell were fabricated. (3) Thermal sintering was performed to fuse the polystyrene and PGMA microspheres into an integral shell of the microcapsules. The durability of the microcapsules before and after sintering was investigated by a suspension test (in water and ethanol) and an accelerated thermal cycling test. The sintering reduced the percentage of leaked dodecanol from 19.6% to 10.3% in the suspension test in ethanol and from 10.4% to 2.8% in the accelerated cycling test. These results verified that the sintering process endowed the prepared microcapsules with better tightness and durability.

Highly stretchable silica/polyacrylamide (PAM) nanocomposite hydrogels were synthesized via in situ free radical polymerization in the presence of silica nanoparticles. The effect of particle size and content of silica nanoparticles on tensile properties and swelling behavior were investigated. The hydrogen bond between PAM molecule and silica nanoparticles was evidenced by Fourier transform infrared spectroscopy and the swelling behavior of hydrogels. The tensile strength of silica/PAM hydrogels is 2 times that of PAM gels, and the elongation at break is nearly 2800% when the silica particle size is 15 nm and the content is 10 wt%. This excellent stretching property of hydrogels was ascribed to the presence of hydrogen bond between PAM molecule and silica nanoparticles.

Surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) was applied to graft poly(glycidyl methacrylate) (PGMA) brushes from macroporous hydrogel templating from oil-in-water high internal phase emulsion (O/W HIPE), and the grafted hydrogel was further heparinized as stationary phase of affinity chromatography for Enterovirus 71 (EV71) purification. Acrylate functional monomer containing isobutyl bromide (HEMA-BiBB) was synthesized and introduced into oil phase for macroporous hydrogel with ATRP initiator-anchored surface. With the increase of HEMA-BIBB dosage, the average pore size of hydrogel increased and the specific surface area decreased. Bromine atomic percent of hydrogel reached the maximum of 1.56 % when the HEMA-BiBB dosage was 1.0 g. The corresponding heparinized hydrogel possessed the highest amount of carboxyl group (56.8 μmol per column). Interconnected macropore (1.71 μm) and high porosity (84.2 %) of heparinized hydrogel ensured an excellent permeability (2.1 × 10−13 m2). Meanwhile, grafted PGMA brushes afforded abundant epoxy groups for immobilizing high density of heparin, which endowed hydrogel with outstanding adsorption capability for EV71. Immobilized heparin ligands were competent in specific capture of EV71 by receptor-ligand interaction. Besides, enhanced hydrophilicity of heparinized hydrogel avoided the irreversible and nonspecific adsorption of proteins. As a result, heparinized hydrogel demonstrated superior adsorption selectivity and capability for EV71 (dynamic adsorption capacity: 1275 ng per column, recovery: 86.2 %). The developed heparinized PGMA-grafted macroporous hydrogel was promising to be applied in the large-scale production of EV71 for vaccine industry.

Monolithic macroporous hydrogels was prepared from oil-in-water high internal phase emulsions (HIPEs) and heparinized using polydopamine (PDA) and polyethyleneimine (PEI) as mediators, and then used as a support of affinity chromatography to purify Enterovirus 71 (EV71) from culture supernatant. Our innovative strategy was characterized by two remits. (1) Interconnected macropores (1–5 μm) and high porosity (76–93%) of hydrophilic hydrogels ensured an excellent permeability (6.95 × 10−13 m2); (2) PDA/PEI composite provided abundant amino groups to immobilize heparin on macroporous hydrogels and increased the amount of carboxyl group to 46.5 μmol per column. A selective recognition of EV71 was achieved by receptor-ligand interaction between heparin and EV71. The adsorption capacity for EV71 was 986.0 ng per column and the recovery for EV71 reached a maximum of 79.9%. It was verified that these high performances were ascribed to the high density of heparin immobilized via PDA and PEI as mediators. Our innovative strategy provided a useful paradigm as a preparation method for heparin-affinity chromatographic medium for virus purification.

Herein we present a systematic study of the antagonistic effect of nanoparticles and nonionic surfactant on pore structure of polymerized high internal phase emulsion (polyHIPE). Interconnected polyHIPE with small voids and large RSD in void size was obtained by surfactant-stabilized emulsion, while a close-cellar polyHIPE with large voids and low RSD in void size was prepared by particles-stabilized emulsion. This antagonistic effect was originated from the different stabilizing mechanism of two different stabilizers. Particles improve the stability of HIPE, and resultantly, endow the polyHIPE with excellent homogeneity; On contrary, surfactant lead to the formation of interconnected void. To obtain polyHIPE with interconnected homogeneous voids, an optimal ratio of surfactant/particle is necessary. The interconnectivity of polyHIPE was first investigated by the loading and releasing property of polyHIPE.

Large size virion is unable to diffuse into pores of conventional porous chromatography particles. Therefore, separation of virion by conventional column-packing materials is not quite efficient. To solve this problem, a monolithic column with large convective pores and quaternary amine groups was prepared and was applied to separate Enterovirus 71 (EV71, ≈5700-6000kDa). Cross-section, pore structure, hydrodynamic performance, adsorption property and dynamic binding capacity of prepared monolithic column were determined. Double-pore structures, macropore at 2472nm and mesopore at 5-60nm, were formed. The porosity was up to 63.3%, which enable higher permeability and lower back pressure of the monolithic column than commercial UNO™ Q1 column. Based on the breakthrough curves, the loading capacity of bovine serum albumin was calculated to be 42.0mg per column. In addition, prepared quaternary amine monolithic column was proved to be suitable for the separation of protein mixture by strong anion-exchange chromatography. As a practical application, prepared monolith column presents excellent performance to the separation of EV71 from virus-proteins mixture.

Brush-like and centipede multigraft copolymers of poly(n-butyl acrylate)–g–poly(styrene) were synthesized via seeded emulsion polymerization under 1,1-diphenylethylene (DPE) and miniemulsion polymerization. Single-tailed and double-tailed poly(styrene) macromonomers were prepared by DPE-technique in emulsion and Steglich esterification. Then poly(n-butyl acrylate)–g–poly(styrene) multigraft copolymers were obtained by miniemulsion copolymerization. The molecular characteristics of poly(styrene) macromonomers and poly(n-butyl acrylate)–g–poly(styrene) have been characterized by gel permeation chromatography. The weight content of poly(styrene) and the number of branch points in brush-like and centipede multigraft copolymers were calculated by proton nuclear magnetic resonance, and the maximum number of branch points is 47. Differential scanning calorimetry analysis and morphological observations by atomic force microscopy confirmed microphase separation in poly(n-butyl acrylate)–g–poly(styrene). Tensile properties showed that brush-like and centipede multigraft copolymers had characteristics of TPEs when the weight content of poly(styrene) in poly(n-butyl acrylate)–g–poly(styrene) was 23 %∼37 %. And centipede multigraft copolymers showed better elastic properties than brush-like multigraft copolymers, which was in line with our previous work.

Magnetic poly(glycidylmethacrylate) microspheres were prepared by dispersion polymerisation in the presence of oleic acid coated Fe3O4 nanoparticles and modified by N-methyl-D-glucamine for the fabrication of magnetic boron specific chelating microspheres. The structure and properties of obtained microspheres were analysed by scanning electron microscopy, Fourier transform infrared spectroscopy and vibrating sample magnetometer. The utility efficiency of monomer reached 60% under an optimum dropwise feeding process. The magnetic microspheres are ∼1 μm in size, and superparamagnetic nanoparticles have a saturation magnetisation of 17.1 emu g− 1 and a Fe3O4 content of 28 wt.%. The resultant boron specific chelating sorbent presents an adsorption capacity of 0.43 mmol g− 1 in the optimum conditions. Fast separation by magnetic field makes the prepared microspheres useful for the purification of boron contaminated water. These microspheres will exhibit strong potential in the treatment of boron contaminated w...

We propose a novel route for the stabilization of oil-in-water Pickering emulsions using inherently hydrophilic nanoparticles. In the case of dialkyl adipate oils, in situ hydrophobisation of the particles by dissolved oil molecules in the aqueous phase enables stable emulsions to be formed. Emulsion stability is enhanced upon decreasing the chain length of the oil due to its increased solubility in the precursor aqueous phase. The oil thus acts like a surfactant in this respect in which hydrogen bonds form between the carbonyl group of the ester oil and the hydroxyl group on particle surfaces. The particles chosen include both fumed and precipitated anionic silica and cationic zirconia. Complementary experiments including relevant oil-water-solid contact angles and infra-red analysis of dried particles after contact with oil support the proposed mechanism.

In this paper, surface-initiated atom transfer radical polymerization (SI-ATRP) on surface of Pickering stabilizer for microencapsulation was investigated. By SI-ATRP on initiator-immobilized SiO2 particles, emulsion droplets were involved into microcapsules. The density of PMMA chains on SiO2 surface reached 1.31 chain nm−2 and the initiator efficiency was estimated to be 28%. The results confirmed that polymerization was confined successfully at the interface of emulsion and 80% of polymer chains were formed via SI-ATRP on Pickering stabilizer. This covalent between SiO2 and polymer endowed the prepared microcapsules with good durability and thermal reliability in phase change materials application.

In this paper, poly(n-butyl acrylate)-g-poly(methyl methacrylate) multigraft copolymers were synthesized by macromonomer technique and miniemulsion copolymerization. The PMMA macromonomers were obtained by an activator generated by electron transfer atom transfer radical polymerization (AGET ATRP) in emulsion system and subsequent allylation. Then the copolymerization of different macromonomers with nBA was carried out in miniemulsion system, obtaining multigraft copolymers with high molecular weight. The latex particles and distribution of emulsion AGET ATRP and miniemulsion copolymerization were characterized using laser light scattering. The molecular weight and polydispersity indices of macromonomers and multigraft copolymers were analyzed by gel permeation chromatography, and the number-average molecular weight range is 187,600–554,800 g/mol for PnBA-g-PMMA copolymers. In addition, the structural characteristics of macromonomer and brush-like copolymers were determined by infrared spectra and 1H nuclear magnetic resonance spectroscopy. The thermal performance of brush-like copolymers were characterized by differential scanning calorimetry and thermogravimetric analysis. Atomic force microscopy results showed that the degree of microphase separation was varying with increasing PMMA content in PnBA-g-PMMA. The dynamic rheometer analysis revealed that multigraft copolymer with PMMA content of 31.4% exhibited good elastomeric properties to function as a TPE. These multigraft copolymers show a promising low cost and environmental friendly thermoplastic elastomer.

Microencapsulated phase change materials (MePCMs) using melamine–formaldehyde resin/SiO2 as shell were investigated in this paper. Organically modified SiO2 particles were employed to stabilize Pickering emulsion, and in situ polymerization of melamine and formaldehyde was carried out to form hybrid shell. The performances of resultant MePCMs with hybrid shell were investigated comparatively with the MePCMs with polymer shell. SiO2 particles raise the microencapsulation efficiency by improving the stability of emulsion and providing a precipitation site for melamine–formaldehyde resin. Also, the mechanical strength, thermal reliability, and anti-osmosis performance of MePCMs were improved significantly by SiO2 particles in the shell. Our study shows that Pickering emulsion is a simple and robust template for MePCMs with polymer-inorganic hybrid shell. Copyright © 2015 John Wiley & Sons, Ltd.

Core–shell polymeric microspheres of tens microns in size with perfect spherical virus-like surface morphology were prepared through Pickering emulsion polymerization. Pickering stabilizer, monodisperse Poly(Glycidyl methacrylate) (PGMA) microsphere were obtained by two-stage dispersion polymerization and acid catalyzed hydrolysis was employed to transform the epoxy groups into glycol groups, rendering the P(GMA) microspheres moderately hydrophilic to stabilize Pickering emulsion. The P(GMA) microspheres and core–shell microspheres were characterized by scanning electronic microscope(SEM), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering(DLS). The results show that monodisperse P(GMA) microspheres were arrayed in a compact hexagonal arrangement on the surface of core–shell microspheres, forming a perfect spherical virus-like surface morphology.

An innovative, rapid and efficient route is developed to fabricate ene loaded microcapsules via a thiol–isocyanate click reaction based on a hydrolyzed poly(glycidyl methacrylate) (PGMA) particle stabilized oil-in-water Pickering emulsion. The whole process for the reaction only requires 10 min, opening up a new, time-saving and energy-efficient strategy. The oil droplets contain isophorone diisocyanate (IPDI), trimethylolpropane tris(3-mercaptopropionate) (TMMP) and 1,3,5-tri-2-propenyl-1,3,5-triazine-2,4,6 (1H, 3H, 5H)-trione (TTT), in which IPDI and TMMP are subsequently catalyzed by triethylamine (TEA) to produce a polythiourethane network, forming microcapsules. From scanning electron microscopy (SEM) and optical microscopy (OM), the resulting microcapsules are in good spherical shape and their outer surface is coated with a compact PGMA particle layer. The mean diameter of the TTT loaded microcapsules decreases from 238.8 to 110 μm with increasing the particle stabilizer concentration. Solid-state 13C NMR measurement proves that almost no side reactions exist in the base-catalyzed thiol–isocyanate reaction. Moreover, the core content (up to 67.8%) and the thickness of the shell wall (8–36 μm) can be adjusted by the feeding amount of core materials. These microcapsules with an outer PGMA layer disperse well and maintain their integrity in the epoxy coating, and no agglomeration is observed. Even though being encapsulated, the core ingredient maintains high reactivity as its raw version and exhibits favorable healing capability. Furthermore, besides TTT, the proposed method is versatile and applicable to the encapsulation of SR833S and diallyl phthalate.

Hexadecane-loaded microcapsules with SiO2–poly(methyl methacrylate) (PMMA) hybrids as shells were prepared by surface-initiated atom transfer radical polymerization (SI-ATRP) in an oil-in-water Pickering emulsion. ATRP-initiators were introduced onto SiO2 particles by a homemade silane coupling reagent containing a 2-bromoisobutyrate group. SI-ATRP polymerization was conducted on Pickering stabilizers based on activators regenerated by electron transfer (ARGET). TGA results indicated that 80.3% of PMMA chains in the shell were covalently-bonded to SiO2, which was formed by SI-ATRP polymerization. The microcapsules show excellent potential for thermal energy storage, as evidenced by a high melting enthalpy of 161.7 J g−1.

Summary Microcapsules with high thermal energy storage density were synthesized by in situ polymerization using melamine–formaldehyde resin as shell and n-hexadecanol as core. Styrene–maleic anhydride (SMA) copolymer was synthesized by solution polymerization and hydrolyzed by NaOH to enhance its water solubility. This negatively charged SMA molecular copolymer self-assembles on the surface of n-hexadecanol droplets and facilitates the precipitation of positively charged melamine–formaldehyde prepolymer onto the droplet surface electrostatically. The morphology, chemical structure, composition, and thermal properties were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, thermal gravimetric analysis, differential scanning calorimetry, and gas chromatography, respectively. The results show that the obtained microencapsulated phase-change material (MePCM) dispersed individually with a spherical shape. Amount of emulsifier, ratio of shell–core material, and pH value of solution have a significant effect on the microencapsulation. Under optimum condition of 8% SMA to core material, 3.3:10 of shell–core material in feed, and polymerization under pH 4.0, spherical n-hexadecanol MePCMs with core content of 79.1% and melting enthalpy of 171 J g−1 at around 51°C were prepared. In situ polymerization based on SMA-stabilized emulsion opens up a route to prepare a variety of microcapsules with aliphatic alcohol as core material. Copyright © 2014 John Wiley & Sons, Ltd.

This paper presented a facile approach to fabricate interconnected multi-hollow polymer microspheres by water-in-oil-in-water (W/O/W) multiple emulsions co-stabilized by SiO2 and Span80. Two-step emulsification was employed to obtain W/O/W emulsion, followed by polymerizing the monomer into the skeleton of microspheres. The inner structure of microspheres was successfully regulated by adjusting the relative amount of SiO2 to Span80. A large range of microspheres with different inner structures was obtained, including close-celled microspheres, interior hollowed microspheres, interconnected microspheres by single channel or multi-channels, and bicontinuous structure. A formation mechanism of microspheres with different inner structure was proposed and verified by the characteristic of released Ca2+ from inner aqueous phase to outer aqueous phase. These microspheres have advantages of high surface area, high porosity, and multi-hollow structure.

MePCMs (microencapsulated phase change materials) with covalently bonded SiO2/polymer hybrid as shell were fabricated via Pickering emulsion polymerization stabilized solely by organically-modified SiO2 particles. Morphology and core–shell structure of these microcapsules were observed by scanning electron microscopy (SEM). Thermal properties of microencapsulated 1-dodecanol were determined using DSC (differential scanning calorimetry) and TGA (thermal gravimetric analysis). The results indicate that mass ratio of St (styrene)/DVB (divinylbenzene)/dodecanol has great effect on the morphology, inner structure, microencapsulation efficiency and durability of resultant MePCMs. When ratio of St/DVB/dodecanol was 5/1/12, dodecanol content of as much as 62.8% is obtained and the utility efficiency of dodecanol reaches 94.2%. The prepared MePCMs present good durability and thermal reliability. 2.2% of core material leached away the microcapsule after suspended in water for 10 days and 5.8% of core material leached after 2000 accelerated thermal cycling. Our study demonstrated that Pickering emulsion polymerization is a simple and robust method for the preparation of MePCMs with polymer–inorganic hybrids as shell.

Three-dimensional “organoid” growth of tumors may represent a more physiologically relevant in vitro model system than traditional two-dimensional monolayer cultures of cancer cell lines. With the increased availability of cryopreserved human cancer organoids generated by academic laboratories, large-scale biobanking initiatives, and commercial sources, there is an unmet need for simplified, standardized, and cost-effective methods for preparation of the complex growth media required by these models. Human organoid culture media contains a variety of recombinant proteins, small molecules, and other growth factors that are costly to purchase in small-scale, time consuming to reconstitute and aliquot, and have varying stability and shelf life once prepared. Organoid culture media often also utilizes undefined conditioned media (CM) from one or more engineered cell lines that must be cultured separately, requiring additional time and resources to maintain. These lines secrete critical growth factors and the CM generated must be carefully prepared, collected, and stored. CM is subject to variability in activity levels due to batch-to-batch and protocol-to-protocol differences that can affect subsequent organoid culture performance. To address these challenges and to facilitate the wide-spread adoption of human organoid culture we are developing reagent kits containing essential growth medium components in an individually lyophilized format for long-term storage and easy single-use preparation of organoid growth media for a variety of tissue types including human colon, mammary, and lung. We compared growth medium formulated with our components with small-scale “homebrew” preparations and found equivalent or better culture performance (as calculated by doubling times) and similar morphology. Both approaches were able to generate media capable of supporting growth for at least three passages (~30 days) in 15 different organoid models. Additionally, we compared protocols and cell lines for CM generation to support organoid culture and found that an optimized, scaled-up production method could generate Wnt-3a and R-spondin1 CM with higher activity levels (up to 52%) and reduced lot-lot variability in comparison with commonly used small-scale protocols. We found that the optimized protocols produced CM that was stable for at least 2 months at 4°C and at least 6 months at -20°C, and was resilient against freezing and thawing. Previously frozen CM was also able to support organoid growth in culture. These results show that our tissue-specific kits and ready-to-use CM can provide a simplified, cost effective method to support the long-term propagation of human cancer organoids from multiple tissues and cancer types. Citation Format: James Clinton, Allison Ruchinskas, Himanshi Desai, Nanda Mahashetty, Dezhong Yin. Propagation of human colon, mammary, and lung cancer organoids in growth medium utilizing tissue-specific reagent kits and ready-to-use Wnt-3a and R-Spondin1 conditioned media [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 51.

Exosomes are subcellular particles 50-200 nm in size released from cells through a fusion of multicellular bodies with the plasma membrane. Exosomes are currently being evaluated as potential diagnostic tools in a number of diseases, including cancer. Exosomes are stable carriers of cell-free cargo in the form of DNA, RNA, and protein, thereby making them an attractive candidate for early detection of cancer via liquid biopsy. Tumor-derived exosomes have been linked to stimulation of tumor cell growth, angiogenesis, metastasis, and suppression of the immune system. However, isolating a consistent population of exosomes can be challenging and there is an unmet need for highly characterized exosomes for use as reference standards for research and diagnostic applications. We have developed a novel method employing tangential flow filtration for the isolation of large quantities of highly purified, ready to use exosomes from cell culture supernatant. Exosomes from a variety of cancer cell lines representing the most prevalent cancer types, including prostate (LNCaP), colorectal (HCT116), breast (MDA-MB-231, MCF-7), lung (A549), cervical (HeLa), and glioblastoma (U87-MG) were isolated and characterized in this study. We employed a stringent quality control approach in order to define and characterize these exosomes. Our method generated a high yield (>1×1010 exosomes/mL) and average protein equivalent of 2 mg/mL. Our data demonstrated expression of a number of different characteristic exosomal proteins including tetraspanin, which was confirmed through western blot and PCR. Isolated exosomes had a median size of 102 nm through nanoparticle tracking analysis. Western blot data revealed cell line specific protein marker expression of CD63, CD81, flotillin 1, Alix and TSG101 protein. We assessed the functionality of these purified exosomes through cellular uptake, migration assay, and anchorage independent growth assay in this study. We also evaluated exosomal RNA from these purified exosomes for the presence of common mutations associated with cancer through PCR. Here we report that exosomes isolated by our method not only had high exosome yield and quality, but also retained relevant functionality and thereby make ideal reference standards/controls in the field of cancer research and diagnostics development. Citation Format: Siddhartha Paul, Nanda Mahashetty, Joy Wells, Dezhong Yin, Fang Tian. Development and characterization of cancer cell line exosomes as reference standards in cancer research [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-038.

This paper describes a novel chemical method for preparing SiO2/TiO2 Janus particles. First, polystyrene (PSt)/SiO2 particles with a raspberry-like structure are prepared by electrostatic assembly. The influences of the reaction time of sulfonation and the treatment times of polyelectrolyte solutions (PDADMAC, PSS) on PSt and SiO2 are investigated with respect to the surface charge density of the particles. SiO2/TiO2 Janus particles are then obtained by hydrolysis of butyl titanate on the surface of PSt/SiO2 particles followed by a calcination process. Particle size analyzer, Zeta potential instrument, FTIR, TEM and SEM are used to characterize the particle size, the amount of charge on the surface of PSt and SiO2 particles and the compositions and morphologies of PSt/SiO2, SiO2/TiO2 and PSt/SiO2/TiO2. The diameters of the PSt, SiO2, PSt/SiO2 and SiO2/TiO2 particles are 2.0 μm, 303 nm, 2.7 μm and 330 nm, respectively.

BSA/Fe3O4 magnetic composite microspheres with high saturation magnetization and paramagnetic property were prepared via inverse emulsion technology at room temperature, bovine serum albumin (BSA, 60 KD), magnetic nanoparticles (Fe3O4) and glutaraldehyde as macromonomer, inorganic particles and cross-linking agent, respectively. Fourier transform infrared (FTIR), scanning electron microscope (SEM), metalloscope, and particle size analyzer were used to characterize morphology and structure of composite microspheres. Vibrating sample magnetometer (VSM) and thermogravimetric analysis (TGA) were used to test magnetic properties of the synthesized samples, adsorption capacity of microspheres was determined by ultraviolet spectrophotometer (UV). The results showed that BSA/Fe3O4 microspheres were 43 μm with relatively narrow particle size distribution, perfect sphere-shaped morphologies, superparamagnetism with a saturation magnetization of 11 emu/g, and high magnetic content with a value of 57.29%. The main factors influencing properties of microspheres including raw material ratio, the amount of emulsifier and cross-linking agent, agitation speed were investigated and optimized. Furthermore, these microspheres accompanying with high separable and reusable efficient may have great potential application in the field of separation, in particular, removal of antibiotics. Adsorption capacities of the microspheres of four different kinds of antibiotics (erythromycin, streptomycin, tetracycline and chloramphenicol) ranging from 69.35 mg/g to 147.83 mg/g were obtained, and Langmuir isotherm model coincided with equilibrium data than that of the Freundlich model.

In this work, Fe3O4/P(acrylic acid-methyl methacrylate-N-isopropylacrylamide) (Fe3O4/P(AA-MMA-NIPAm)) thermoresponsive magnetic composite microspheres have been prepared by controlled radical polymerization in the presence of 1,1-diphenylethene (DPE). The shell thickness of thermosensitive polymer (PNIPAm), which was on the surface of the microspheres, can be controlled by using DPE method. The morphology and thermosensitive properties of the composite microspheres, polymerization mechanism of the shell were characterized by TEM, FTIR, VSM, Laser Particle Sizer, TGA, NMR, and GPC. The microspheres with narrow particle size distribution show high saturation magnetization and superparamagnetism. The thermosensitive properties of the composite microspheres can be adjusted indirectly via controlling the addition amount of monomer (NIPAm) in the second step during controlled radical polymerization. Phenolphthalein was chosen as a model drug to investigate drug release behavior of the thermoresponsive magnetic composite microspheres with different shell thickness. Controlled drug release testing reveals that the release behavior depends on the thickness of polymer on the surface of the microspheres.

Covalently bonded polystyrene/SiO2 microspheres were synthesised via Pickering emulsion polymerisation using methacryloxypropyltrimethoxysilane modified SiO2 as a sole stabiliser. The effect of polymerisation condition on morphologies of composites was investigated, and a formation mechanism of microspheres with different morphologies was proposed. Three strategies, increasing amount of stabiliser, adding inhibitor in continuous phase and employing cross-linking agent, were employed to regulate the morphology of products. It was concluded that suppression of nucleation in continuous phase was critical for the formation of dispersive microspheres with high sphericity and smooth surface.

Facile one-step Pickering emulsion polymerization was employed to prepare magnetic polymer microspheres with high magnetism and armored inorganic particles. Partially hydrophilic CTAB-modified Fe 3 O 4 particles were employed as stabilizer of Pickering emulsion and were armored on the as-prepared microspheres, while totally hydrophobic oleic acid-modified Fe 3 O 4 particles were encapsulated in the obtained microspheres. The microspheres were characterized by scanning electron microscopy (SEM), energy dispersive X-ray microanalyses (EDX) and magnetic measurements. Total Fe 3 O 4 , encapsulated Fe 3 O 4 and armored Fe 3 O 4 were detected and catalytic activity of microspheres for Fenton reaction was evaluated. The results showed that steady barrier formed by CTAB-modified Fe 3 O 4 on droplet surface can prevent oleic acid-modified Fe 3 O 4 from escaping away the polymerization vessel, which lead to an efficient encapsulation to oleic acid-modified Fe 3 O 4 . The encapsulated Fe 3 O 4 enables the microspheres to be separated by external magnetic field and the armored Fe 3 O 4 endows the composites with special catalytic property.

The first guidance on Good Cell Culture Practice (GCCP) dates back to 2005. This document expands this to include aspects of quality assurance for in vitro cell culture focusing on the increasingly diverse cell types and culture formats used in research, product development, testing and manufacture of biotechnology products and cell-based medicines. It provides a set of basic principles of best practice that can be used in training new personnel, reviewing and improving local procedures, and helping to assure standard practices and conditions for the comparison of data between laboratories and experimentation performed at different times. This includes recommendations for the documentation and reporting of culture conditions. It is intended as guidance to facilitate the generation of reliable data from cell culture systems, and is not intended to conflict with local or higher level legislation or regulatory requirements. It may not be possible to meet all recommendations in this guidance for practical, legal or other reasons. However, when it is necessary to divert from the principles of GCCP, the risk of decreasing the quality of work and the safety of laboratory staff should be addressed and any conclusions or alternative approaches justified. This workshop report is considered a first step toward a revised GCCP 2.0.

One-dimensional (ID) magnetic thermosensitive Fe3O4/poly(N-isopropylacrylamide–N,N′-methylenebisacrylamide) (P(NIPAM-MBA)) peapod-like nanochains have been successfully synthesized by magnetic-field-induced precipitation polymerization using Fe3O4 as building blocks and P(NIPAM-MBA) as linker. Fe3O4 microspheres can be arranged with the direction of an external magnetic field in a line via the dipolar interaction between Fe3O4 microspheres and linked permanently via P(NIPAM-MBA) coating during precipitation polymerization. 1D magnetic Fe3O4/P(NIPAM-MBA) peapod-like nanochains can be oriented and aligned along the direction of the external magnetic field. More interestingly, Fe3O4 microspheres in each peapod were regularly arranged in a line and periodically separated through the P(NIPAM-MBA) layers with a visible interparticle spacing.

One-dimensional (1D) magnetic Fe(3)O(4)/P(GMA-DVB) peapod-like nanochains have been successfully synthesized by magnetic-field-induced precipitation polymerization using Fe(3)O(4) as building blocks and P(GMA-DVB) as linker. The Fe(3)O(4) microspheres without surface modification can be arranged with the direction of the external magnetic field in a line via the dipolar interaction between Fe(3)O(4) microspheres and linked permanently via P(GMA-DVB) coating during precipitation polymerization. The length of peapod-like nanochains can be controlled by magnetic field intensity, and the thickness of polymer shell can be tuned by the amount of monomers. Magnetic measurement revealed that these 1D peapod-like nanochains showed highly magnetic sensitivity. In the presence of magnetic field, 1D magnetic Fe(3)O(4)/P(GMA-DVB) peapod-like nanochains can be oriented and aligned along the direction of external magnetic field.

A magnetically separable Fe 3 O 4 –NH 2 –Pd (0) catalyst was easily synthesized by immobilizing Pd nanoparticles on the surface of magnetic Fe 3 O 4 –NH 2 microspheres. It was found that the combination of Fe 3 O 4 and triethylene tetramine (TETA) could give rise to structurally stable catalytic sites. Furthermore, the high-magnetization Fe 3 O 4 –NH 2 –Pd(0) catalyst can be recovered by magnet and reused for six runs for Heck reaction without significant loss in catalytic activity.