pH Responsive Behavior of Fe3O4@PDEA-PEGMA Core-Shell Hybrid Magnetic Nanoparticles

Increasing antibiotic resistance in bacteria that cause zoonotic infections is a major problem for farmers rearing animals for food as well as for consumers who eat the contaminated meat resulting in food-borne infections. Bacteriophages incorporated in animal feed may help reduce carriage and infections in animals including chickens and pigs. There are, however, unmet challenges in protecting phages from processing stresses e.g., during animal feed pelleting operations and during transit of phages through the acidic gastric environment. Core-shell capsules were produced using a concentric nozzle and commercially available encapsulation equipment to fabricate capsules with phages formulated in an oil-in-water microemulsion in the core. pH-responsive capsules released the encapsulated phage cargo within 10–30 min triggered by changes in local environmental pH typically found in the lower gastrointestinal (GI) tract of animals. Acid stability of phages exposed to pH values as low as pH 1 was demonstrated. Encapsulated phages were able to withstand exposure to 95 °C wet heat thermal stress for up to 120 s, conditions typically encountered during feed pellet extrusion processing. Free phages were inactivated within 15 s under these conditions. The present study demonstrates that encapsulation of bacteriophages in core-shell pH-responsive capsules with water-in-oil emulsified phages in the core significantly improves phage viability upon exposure to processing and environmental stresses that require consideration during production of animal feed and application in animals for biocontrol. The results from this study should help guide future development of phage formulations suitable for use in animal feed for animal biocontrol applications.

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Regulating redox and pH- responsive behavior of emulsion by varying alkane carbon number of tertiary amine

Journal of Dispersion Science and Technology ◽

10.1080/01932691.2020.1857265 ◽

2020 ◽

pp. 1-8

Author(s):

Xin Lv ◽

Xiaojiang Li ◽

Peiyao Zhu ◽

Yang Ge ◽

Qingping Li ◽

...

Keyword(s):

Tertiary Amine ◽

Carbon Number ◽

Ph Responsive ◽

Responsive Behavior

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Water-soluble polymers. 71. pH responsive behavior of terpolymers of sodium acrylate, acrylamide, and the zwitterionic monomer 4-(2-acrylamido-2-methylpropanedimethylammonio)butanoate

Journal of Polymer Science Part A Polymer Chemistry ◽

10.1002/(sici)1099-0518(19970130)35:2<231::aid-pola5>3.0.co;2-v ◽

1997 ◽

Vol 35 (2) ◽

pp. 231-242 ◽

Cited By ~ 21

Author(s):

Erich E. Kathmann ◽

Charles L. McCormick

Keyword(s):

Water Soluble ◽

Sodium Acrylate ◽

Ph Responsive ◽

Water Soluble Polymers ◽

Soluble Polymers ◽

Responsive Behavior

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Magneto-Optical Characteristics of Streptavidin-Coated Fe3O4@Au Core-Shell Nanoparticles for Potential Applications on Biomedical Assays

Scientific Reports ◽

10.1038/s41598-019-52773-7 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Chin-Wei Lin ◽

Jian-Ming Chen ◽

You-Jun Lin ◽

Ling-Wei Chao ◽

Sin-Yi Wei ◽

...

Keyword(s):

Magnetic Nanoparticles ◽

Faraday Effect ◽

Au Nanoparticles ◽

Optical Characteristics ◽

Enzyme Linked Immunosorbent Assay ◽

Core Shell ◽

Shell Nanoparticles ◽

Time Resolved ◽

Biotechnology Research ◽

Core Shell Nanoparticles

Abstract Recently, gold-coated magnetic nanoparticles have drawn the interest of researchers due to their unique magneto-plasmonic characteristics. Previous research has found that the magneto-optical Faraday effect of gold-coated magnetic nanoparticles can be effectively enhanced because of the surface plasmon resonance of the gold shell. Furthermore, gold-coated magnetic nanoparticles are ideal for biomedical applications because of their high stability and biocompatibility. In this work, we synthesized Fe3O4@Au core-shell nanoparticles and coated streptavidin (STA) on the surface. Streptavidin is a protein which can selectively bind to biotin with a strong affinity. STA is widely used in biotechnology research including enzyme-linked immunosorbent assay (ELISA), time-resolved immunofluorescence (TRFIA), biosensors, and targeted pharmaceuticals. The Faraday magneto-optical characteristics of the biofunctionalized Fe3O4@Au nanoparticles were measured and studied. We showed that the streptavidin-coated Fe3O4@Au nanoparticles still possessed the enhanced magneto-optical Faraday effect. As a result, the possibility of using biofunctionalized Fe3O4@Au nanoparticles for magneto-optical biomedical assays should be explored.

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