Release Of Bovine Serum Albumin Research Articles

Asymmetric Triblock Copolymer Nanocarriers for Controlled Localization and pH-Sensitive Release of Proteins.

Designing nanocarriers to release proteins under specific conditions is required to improve therapeutic approaches, especially in treating cancer and protein deficiency diseases. We present here supramolecular assemblies based on asymmetric poly(ethylene glycol)-b-poly(methylcaprolactone)-b-poly(2-(N,Ndiethylamino)ethyl methacrylate) (PEG-b-PMCL-b-PDMAEMA) copolymers for controlled localization and pH-sensitive release of proteins. Copolymers self-assembled in soft nanoparticles with a core domain formed by PMCL, and a hydrophilic domain based on PEG mainly embedded inside, and the branched PDMAEMA exposed at the particle surface. We selected as model proteins to be attached to the nanoparticles bovine serum albumin (BSA) and acid sphingomyelinase (ASM), the latter being an ideal candidate for protein replacement therapy. The hydrophilic/hydrophobic ratio, nanoparticle size, and the nature of biomolecules are key factors for modulating protein localization and attachment efficiency. The predominant outer shell of PDMAEMA allows efficient pH-triggered release of BSA and ASM, and in acidic conditions >70% of the bound proteins were released. Uptake of protein-attached nanoparticles by HELA cells, together with low toxicity and pH-responsive release, supports such protein-bound nanoparticles as efficient stimuli-responsive candidates for protein therapy.

Ca(II)+Ba(II) ions crosslinked alginate gels prepared by a novel diffusion through dialysis tube (DTDT) approach and preliminary BSA release study

In this work, plain and model therapeutic protein Bovine Serum Albumin(BSA) loaded alginate hydrogels, crosslinked with Ca(II)+Ba(II) ions, were prepared by ‘Diffusion Through Dialysis Tube’ (DTDT) technique which involved permeation of crosslinking ions into alginate solution via a dialysis tube with a molecular weight cutoff of 8 k Da. The model protein BSA loaded hydrogels were characterized by Fourier transform infrared (FTIR) and X-ray diffraction (XRD) analysis. The dynamic water uptake behavior of plain hydrogels was investigated in phosphate buffer saline (PBS) of pH 7.4 at 37 °C. Finally, the controlled release of therapeutic protein BSA from these hydrogels was studied in the phosphate buffer medium of pH 7.4 at 37 °C.The release data were interpreted in the terms of Power function model and First order kinetic model respectively.

Biodegradable star-shaped polycyclic ester elastomers: Preparation, degradability, protein release, and biocompatibility in vitro

Effective local delivery methods for sustained and stable release of protein drugs are urgently needed. Biodegradable elastomers based on star-shaped polycyclic esters have received attention for their drug-loading and drug-release kinetics. However, the long degradation periods resulting from their strong lipophilicity greatly hinder their application. In this study, we synthesized new cross-linked elastomers based on methyl-acrylic-star-poly(ϵ-caprolactone- co-d,l-lactide) cyclic ester and methyl-bi-acrylic-poly(ϵ-caprolactone-b-poly(ethylene glycol)-b-ϵ-caprolactone) with different molecular weights; determined their physical, thermal, and morphological characteristics; and studied their in vitro degradation and release of bovine serum albumin and recombinant human interleukin 2. Elastomer hydrophilicity improved with the introduction of methyl-bi-acrylic-poly(ϵ-caprolactone-b-poly(ethylene glycol)-b-ϵ-caprolactone), and a shorter degradation period (~25 weeks) was achieved. Additionally, the degradation rate could be adjusted by varying the composition of methyl-bi-acrylic-poly(ϵ-caprolactone-b-poly(ethylene glycol)-b-ϵ-caprolactone) to directly influence the degree of swelling, cross-linking density, and sol content of the elastomer. The controlled rate of bovine serum albumin and recombinant human interleukin 2 release increased with a larger degree of swelling, higher sol content, and lower cross-link density of the elastomers. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide analysis showed good biocompatibility. These results suggest that these new elastomers are potential candidates for carrier materials in controlled, implantable delivery systems for protein drugs and other biomedical applications.

Preparation of chitosan/pumpkin polysaccharide hydrogel for potential application in drug delivery and tissue engineering

Biological hydrogel is important in drug delivery system and tissue engineering. In this paper, we prepared a series of biological hydrogels with N,O-carboxymethyl chitosan and oxidized pumpkin polysaccharide-II (oxidized PP-II). Morphological analyses indicated that the N,O-carboxymethyl chitosan/oxidized PP-II hydrogels (CPHs) had porous interior structures. The pore diameters ranged from several tens to several hundreds of micrometers. The storage modulus (G′) of the hydrogels ranged from 11 to 77 Pa, which indicated that the hydrogels had suitable mechanical strength. In vitro release test showed that the cumulative release of bovine serum albumin decreased from 95 to 60 % along with the proportion of oxidized PP-II to N,O-carboxymethyl chitosan from 1:1 to 1:3. After CPH-2 implanted in muscle tissues of mice for 15 days, fibroblast grew well in the CPH-2 pieces without inflammatory reaction. Therefore, the CPH-2 presented good histocompatibility with the muscle tissues of mice. Taken together, the N,O-carboxymethyl chitosan/oxidized PP-II hydrogels (CPHs) might have potential applications in the drug delivery system and tissue engineering.

Dual Stimuli Responsive Gelatin‐CNT Hybrid Films as a Versatile Tool for the Delivery of Anionic Drugs

Hybrid hydrogel films able to modulate the release of anionic species, ketoprofen (Ket) and bovine serum albumin (BSA), as a function of their molecular size are prepared by UV‐induced polymerization of methacrylated gelatin in the presence of oxidized multiwalled carbon nanotubes (MWNT_COOH). The dual‐stimuli responsive composites can modulate the release in response to the variation of temperature and the application of an external voltage. Drug release profiles, analyzed by mathematical models, show that different temperatures (25 and 45 °C) and applied voltages (0 and 36 V) have a different effect on the release of the two therapeutics. Ket release is enhanced at 45 °C (77% vs 22% at 25 °C) with the maximum value recorded when 36 V is applied (94%). An increase in the amount of released BSA is recorded at 45 °C (96% vs 50% at 25 °C), while the application of the external voltage reduces this value (39%).image

Application of the dry‐spinning method to produce poly(ε‐caprolactone) fibers containing bovine serum albumin laden gelatin nanoparticles

ABSTRACTWe designed and manufactured a polymeric system with combined hydrophilic–hydrophobic properties by loading gelatin nanoparticles (GNPs) containing bovine serum albumin (BSA) into poly(ε‐caprolactone) (PCL) fibers. Our ultimate goal was to create a device capable of carrying and releasing protein drugs. Such a system could find several biomedical applications, such as those in controlled release systems, surgical sutures, and bioactive scaffolds for tissue engineering. A two‐step desolvation method was used to produce GNPs, whereas PCL fibers were produced by a dry‐spinning method. The morphological, mechanical, and thermal properties of the produced system were investigated, and the distribution of nanoparticles both inside and on the surface of the fibers was examined. The effect of the particles on the biodegradability of the fibers was also evaluated. In vitro preliminary tests were performed to study the release of BSA from nanoparticle‐laden fibers and to compare this with its release from free nanoparticles. Our results indicate that the distribution of particles inside the fibers was quite homogeneous and only a few of them were present on the surface. The presence of the particles in the fibers did not affect the thermal properties of the PCL polymer matrix, although it created voids that affected the degradation characteristics so the PCL fibers favored faster erosion compared to the plain fibers. Preliminary results indicate that the release from GNP‐laden fibers occurred much more slowly compared to that in the free GNPs. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44233.

Chemical treatment and chitosan coating of yeast cells to improve the encapsulation and controlled release of bovine serum albumin

We investigate the encapsulation of bovine serum albumin (BSA) in chemical-treated and chitosan-coated yeast cells, Saccharomyces cerevisiae (S. cerevisiae), for the controlled release of BSA. The chemical treatment can sufficiently enlarge the small-sized cell-wall cavities and/or break the integrity for the entrance of BSA to the interior of yeast cells, and the additional chitosan coating can well prevent the rapid release of encapsulated BSA from the yeast-derived microcapsules. The sodium hydroxide pretreated S. cerevisiae gives a maximum encapsulation yield of (10.1 ± 0.2)% for BSA. An additional coating of S. cerevisiae with chitosan can reduce the initial burst release of BSA and extend the release period from 24 h in the chitosan-free case to 48 h in phosphate buffer at pH 7.4. The prepared microcapsules can well keep the shapes and sizes of yeast cells and thus show uniform sizes of 3.85 ± 0.81 μm. The encapsulated BSA well retains its pristine ultraviolet spectroscopic and chromatographic behaviors. The present microencapsulation protocol has the advantages of convenient and mild operation, high encapsulation efficiency, and organic solvent-free nature, which is of reference value for establishing high-performance controllable biomacromolecule-delivery systems.

PH-Responsive Polyethylene Glycol Monomethyl Ether-ε-Polylysine-G-Poly (Lactic Acid)-Based Nanoparticles as Protein Delivery Systems.

The application of poly(lactic acid) for sustained protein delivery is restricted by the harsh pH inside carriers. In this study, we synthesized a pH-responsive comb-shaped block copolymer, polyethylene glycol monomethyl ether-ε-polylysine-g-poly (lactic acid) (PEP)to deliver protein (bovine serum albumin (BSA)). The PEP nanoparticles could automatically adjust the internal pH to a milder level, as shown by the quantitative ratio metric results. The circular dichroism spectra showed that proteins from the PEP nanoparticles were more stable than those from poly(lactic acid) nanoparticles. PEP nanoparticles could achieve sustained BSA release in both in vitro and in vivo experiments. Cytotoxicity results in HL-7702 cells suggested good cell compatibility of PEP carriers. Acute toxicity results showed that the PEP nanoparticles induced no toxic response in Kunming mice. Thus, PEP nanoparticles hold potential as efficient carriers for sustained protein release.

Stable thermosensitive in situ gel-forming systems based on the lyophilizate of chitosan/α,β-glycerophosphate salts

In the present study, lyophilization was attempted to improve the long-term storage of CS/GP thermogelling systems for biopharmaceutical applications. After lyophilization, CS/α,β-GP lyophilizate could not be dissolved in water, but some metal salts, such as NaCl, CaCl2, and MgCl2 surprisingly facilitated its dissolution. X-ray powder diffraction analysis suggested that calcium ions might preferentially form salts with α,β-GP, inhibit the transfer of protons from CS to α,β-GP, and then inhibit the aggregation of CS molecules during lyophilization. Comparison of the freshly prepared CS/α,β-GP/salt solutions and the reconstituted solutions from lyophilizates showed that lyophilization clearly influenced the properties of reconstituted CS/α,β-GP/salt solutions such as gelation time, viscosity, and pH. Furthermore, the reconstituted CS/α,β-GP/CaCl2 solutions maintained thermogelling properties and formed hydrogels at 37°C within approximately 5min, but did not form hydrogels at 20°C and 4°C over 2 weeks. The model protein bovine serum albumin (BSA) was further incorporated into the CS/α,β-GP/CaCl2 system. In vitro release experiments showed the sustained release of BSA from CS/α,β-GP/CaCl2 hydrogels in a pH-sensitive manner, demonstrating that CS/α,β-GP/CaCl2 may be useful as an in situ gel-forming system.

Genipin-crosslinked O-carboxymethyl chitosan-gum Arabic coacervate as a pH-sensitive delivery system and microstructure characterization.

The possibility of genipin-crosslinked O-carboxymethyl chitosan-gum Arabic coacervate as a pH-sensitive delivery vehicle was investigated. O-carboxymethyl chitosan-gum Arabic coacervates separated in pH 3.0, 4.5, and 6.0 were crosslinked by genipin for different durations and the crosslinked products were subjected to crosslinking degree, swelling behavior, bovine serum albumin release profile, and microstructure characterization. Genipin-crosslinking greatly improved the stability of the coacervates against the simulated gastric solution and created certain pH-sensitivity. The coacervates displayed higher swelling ratios in the simulated gastric solution than in the simulated intestine and colon solutions; meanwhile, the coacervates prepared in pH 4.5 and 6.0 swelled more severely than the complex separated in pH 3.0. Nevertheless, the bovine serum albumin release in the simulated gastric solution from the microcapsules prepared in pH 6.0 was much lower than those prepared in pH 4.5 and 3.0, whose cumulative release percentages in the three simulated solutions were 17.14%, 55.23%, and 79.79%, respectively, in crosslinking duration 2 h. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy analysis revealed that genipin-crosslinking improved the regularity and compactness of coacervate structure, whereas confocal laser scanning microscopy observation indicated that O-carboxymethyl chitosan content was possibly the major reason for the different swelling and bovine serum albumin release behavior of the coacervates. It was concluded that the genipin-crosslinked O-carboxymethyl chitosan-gum Arabic coacervate was a potential intestine-targeted delivery system and its delivery performance could be tailored by varying the crosslinking degree and coacervation acidity.

Development of amphoteric alginate/aminated chitosan coated microbeads for oral protein delivery

A new amphoteric biopolymer carrier based on alginate and aminated chitosan coated microbeads (Alg/AmCS) was developed and characterized for bovine serum albumin (BSA) protein delivery. The amphoteric character was investigated through studying the swelling and in vitro BSA release behaviors of the developed microbeads in simulated gastric (SGF; pH1.2), intestinal (SIF; pH6.8), and colonic (SCF; pH7.4) fluids. The pH sensitivity was found to depend on the amount of AmCS in the coating medium. The results were interpreted from the view of the individual pH sensitivity of alginate and aminated chitosan in addition to the ionic interaction between them under the studied pHs. Besides; it was found that the BSA loading efficiency (LE) exceeded 82% regardless of the initial concentration of BSA. The released amount of BSA reached approximately 63% and 86% in SIF and SCF, respectively, using 0.25% AmCS. The stability of alginate microbeads in SCF was improved with increasing AmCS concentration in the coating medium up to 2%. Furthermore, the developed microbeads demonstrated their ability for biodegradation in addition to their antibacterial activities against selected bacterial strains. The results clearly suggested that Alg/AmCS coated microbeads could be suitable carriers for site-specific protein delivery in the intestinal and colon tracts.

3D printing enables separation of orthogonal functions within a hydrogel particle.

Multifunctional particles with distinct physiochemical phases are required by a variety of applications in biomedical engineering, such as diagnostic imaging and targeted drug delivery. This motivates the development of a repeatable, efficient, and customizable approach to manufacturing particles with spatially segregated bioactive moieties. This study demonstrates a stereolithographic 3D printing approach for designing and fabricating large arrays of biphasic poly (ethylene glycol) diacrylate (PEGDA) gel particles. The fabrication parameters governing the physical and biochemical properties of multi-layered particles are thoroughly investigated, yielding a readily tunable approach to manufacturing customizable arrays of multifunctional particles. The advantage in spatially organizing functional epitopes is examined by loading superparamagnetic iron oxide nanoparticles (SPIONs) and bovine serum albumin (BSA) in separate layers of biphasic PEGDA gel particles and examining SPION-induced magnetic resonance (MR) contrast and BSA-release kinetics. Particles with spatial segregation of functional moieties have demonstrably higher MR contrast and BSA release. Overall, this study will contribute significant knowledge to the preparation of multifunctional particles for use as biomedical tools.

Tandem Delivery Platform for Small Molecules and Biologic Pharmaceuticals Via Silicone Foam1

Tandem Delivery Platform for Small Molecules and Biologic Pharmaceuticals Via Silicone Foam1

Gelatin/Carboxymethyl chitosan based scaffolds for dermal tissue engineering applications

The present study delineates the preparation, characterization and application of gelatin-carboxymethyl chitosan scaffolds for dermal tissue engineering. The effect of carboxymethyl chitosan and gelatin ratio was evaluated for variations in their physico-chemical-biological characteristics and drug release kinetics. The scaffolds were prepared by freeze drying method and characterized by SEM and FTIR. The study revealed that the scaffolds were highly porous with pore size ranging between 90 and 170μm, had high water uptake (400–1100%) and water retention capacity (>300%). The collagenase mediated degradation of the scaffolds was dependent on the amount of gelatin present in the formulation. A slight yet significant variation in their biological characteristics was also observed. All the formulations supported adhesion, spreading, growth and proliferation of 3T3 mouse fibroblasts. The cells seeded on the scaffolds also demonstrated expression of collagen type I, HIF1α and VEGF, providing a clue regarding their growth and proliferation along with potential to support angiogenesis during wound healing. In addition, the scaffolds showed sustained ampicillin and bovine serum albumin release, confirming their suitability as a therapeutic delivery vehicle during wound healing. All together, the results suggest that gelatin-carboxymethyl chitosan based scaffolds could be a suitable matrix for dermal tissue engineering applications.

Surface functionalization of zirconium dioxide nano-adsorbents with 3-aminopropyl triethoxysilane and promoted adsorption activity for bovine serum albumin

Surface functionalization of zirconium dioxide (ZrO2) nano-adsorbents was carried out by using 3-aminopropyl triethoxysilane (APTES) as the modifier. The addition amount of APTES was varied to determine the optimum modification extent, and the bulk ZrO2 microparticles were also modified by APTES for comparison. Some means, such as TEM, XRD, FT-IR, XPS and TG-DSC were used to character these ZrO2 particles. The results showed that the APTES molecules were chemically immobilized on the surface of ZrO2 nanoparticles via ZrOSi bonds, and the nano-ZrO2 samples showed larger special surface area. In the adsorption of bovine serum albumin (BSA), nano-ZrO2 samples exhibited enhanced adsorption activity, and APTES modified nano-ZrO2 with proper APTES content presented the best adsorption property. Under the same adsorption conditions, the equilibrium adsorption capacity of BSA on APTES-ZrO2-2 was almost 2.3 times as that on pristine nano-ZrO2 and 3.0 times as on bulk ZrO2 microparticles. The increased adsorption capacity of APTES-ZrO2 nano-adsorbents can be attributed to the chemical interaction between amino and carboxyl groups at APTES-ZrO2/BSA interface. The pH-dependent experiments showed that the optimum pH value for the adsorption and desorption was 5.0 and 9.0, respectively, which suggested that the adsorption and release of BSA could be controlled simply by adjusting the solution pH condition.

Core–Shell Structured Chitosan–Carbon Nanotube Membrane as a Positively Charged Drug Delivery System: Selective Loading and Releasing Profiles for Bovine Serum Albumin

Here we present carbon nanotube (CNT) buckypaper with efficient loading and releasing patterns for negatively charged drug. Carbonaceous membrane (Chit–NH2 /CNT) with three‐dimensionally interwoven porous nanostructure and positive surface was prepared by self‐assembly of CNT fibers hybridized with chitosan (Chit–NH2 ) in core–shell structure. Transmission electron microscopy and scanning electron microscopy images clearly showed that core–shell structured Chit–NH2 /CNT fibers and countless nanosized pores at less than 30 nm in length were formed between positively charged Chit–NH2 /CNT fibers. Based on Brunauer–Emmett–Teller N2 ‐adsorption method, the surface area, average pore size, and pore volume were approximately 19.7 m2/g, 9.54 nm, and 0.043 cc/g, respectively. Bovine serum albumin (BSA) loading and releasing profiles of these carbonaceous membrane constructed with positively charged CNT fibers were tested. The maximum entrapment of BSA was at a loading capacity of 0.65 mg/mg for 1.0 mg of Chit–NH2 /CNT hybrid membrane. The maximum release of BSA was about 65% of the entrapped amount for 1.0 mg of Chit–NH2 /CNT hybrid membrane. BSA was almost continuously released over the 11‐day period at a rate of about 0.23 g/day. Chit–NH2 /CNT hybrid membranes showing impressive drug‐loading/‐releasing characteristics could be potentially used as transdermal drug delivery system for negatively charged drugs in the medicinal field and tissue regeneration area.

Preparation, characterization and in vitro release study of BSA-loaded double-walled glucose-poly(lactide-co-glycolide) microspheres.

The aim of this study was to prepare a model protein, bovine serum albumin (BSA) loaded double-walled microspheres using a fast degrading glucose core, hydroxyl-terminated poly(lactide-co-glycolide) (Glu-PLGA) and a moderate-degrading carboxyl-terminated PLGA polymers to reduce the initial burst release and to eliminate the lag phase from the release profile of PLGA microspheres. The double-walled microspheres were prepared using a modified water-in-oil-in-oil-in-water (w/o/o/w) method and single-polymer microspheres were prepared using a conventional water-in-oil-in-water (w/o/w) emulsion solvent evaporation method. The particle size, morphology, encapsulation efficiency, thermal properties, in vitro drug release and structural integrity of BSA were evaluated in this study. Double-walled microspheres prepared with Glu-PLGA and PLGA polymers with a mass ratio of 1:1 were non-porous, smooth-surfaced, and spherical in shape. A significant reduction of initial burst release was achieved for the double-walled microspheres compared to single-polymer microspheres. In addition, microspheres prepared using Glu-PLGA and PLGA polymers in a mass ratio of 1:1 exhibited continuous BSA release after the small initial burst without any lag phase. It can be concluded that the double-walled microspheres made of Glu-PLGA and PLGA polymers in a mass ratio of 1:1 can be a potential delivery system for pharmaceutical proteins.

Formulation and Characterization of Bovine Serum Albumin-Loaded Niosome.

Niosomal vesicle, as a unique novel drug delivery system, is synthesized by non-ionic surfactants. Both hydrophilic and lipophilic drugs and also biomacromolecular agents, such as peptides and proteins can be encapsulated in this vesicular particle. Regarding polypeptide-based component loading, and delivery potential of the niosome, some valuable studies have been conducted in recent years. However, exploring the full potential of this approach requires fine tuned optimization and characterization approaches. Therefore, this study was conducted to achieve the following two goals. First, formulation and optimization of bovine serum albumin (BSA) load and release behavior as a function of cholesterol (CH) to sorbitan monostearate (Span 60) molar ratio. Second, investigating a cost- and time-effective polypeptide detecting method via methyl orange (MO) dye. To this aim, BSA-loaded niosomes were prepared by reversed-phase evaporation technique. The effect of CH to Sorbitan monostearate (Span 60) molar ratio on noisome entrapment efficiency (EE%) and release profile of BSA was studied using a ultraviolet (UV) spectrophotometer technique (NanoDrop 2000/2000c).Niosome with a 60% CH content showed the highest BSA EE% and release behavior. Then, BSA was dyed using MO in an acidic solution and used in BSA-niosome formulation. The MO-colored protein, loaded into the vesicles, was successfully assessed by an inverted light microscope, in order to observe the protein location in the vesicle. The results obtained in this study can be useful for various applications in different fields, including pharmaceutical, cosmetics, and drug delivery in biomedical and tissue engineering.

Synthesis, characterization, and cytotoxicity of star‐shaped polyester‐based elastomers as controlled release systems for proteins

ABSTRACTWith the growing number of therapeutic proteins on the market, effective delivery systems are receiving particular attention. In this study, biodegradable elastomers, intended for protein drug delivery and based on methacrylic tripoly(ε‐caprolactone‐co‐d,l‐lactide) cyclic ester with different ratios of ɛ‐caprolactone tod,l‐lactide and methacrylic bipoly[ɛ‐caprolactone‐b‐poly(ethylene glycol)‐b‐ɛ‐caprolactone], were synthesized and characterized. The degradation behavior, bovine serum albumin (BSA)‐releasing kinetics, and cytotoxicity of the elastomersin vitrowere investigated. The elastomers were degraded by the hydrolysis of the ester bond; this resulted in pH changes, which further affected the degradation rate. The BSA‐releasing behavior was strongly dependent on the diffusion mechanism. In the diffusion‐controlled period, nearly sustained and stable BSA release was achieved. Furthermore, the elastomers displayed good biocompatibility, as demonstrated by a 3‐(4,5‐dimethyl thiazol‐2‐yl)−2,5‐diphenyl tetrazolium bromide assay and inflammation–induction experiments, and are considered promising candidates for the controllable delivery of protein drugs. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2016,133, 43393.

Controlled release of protein from magnetite–chitosan nanoparticles exposed to an alternating magnetic field

ABSTRACTIn this research, the controlled release of proteins from magnetite (Fe3O4)–chitosan (CS) nanoparticles exposed to an alternating magnetic field is reported. Fe3O4–CS nanoparticles were synthesized with sodium tripolyphosphate (TPP) molecules as a crosslinking reagent. Bovine serum albumin (BSA) was used as a model protein, and its controlled release studied through the variation of the frequency of an alternating magnetic field. The results show the successful coating of CS and BSA on the Fe3O4 nanoparticles with an average diameter of 50 nm. Intermolecular interactions of TPP with CS and BSA were confirmed by Fourier transform infrared spectroscopy. The application of low‐frequency alternating magnetic fields to such magnetic CS nanoparticles enhanced the protein release properties, in which the external magnetic fields could switch on the unloading of these nanoparticles. We concluded that enhanced BSA release from nanoparticles exposed to an alternating magnetic field is a promising method for achieving both the targeted delivery and controlled release of proteins. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43335.