Polymeric Microcapsules Research Articles

Degradable, thermo-, pH- and redox-sensitive hydrogel microcapsules for burst and sustained release of drugs.

Polymer microcapsules offer a possibility of storing increased amounts of drugs. Appropriate design and composition of the microcapsules allow tuning of the drug-release process. In this paper, we report on synthesis of hydrogel microcapsules sensitive to temperature and pH and degradable by glutathione and hydrogen peroxide. Microcapsules were based on thermo-responsive poly(N-isopropylacrylamide) and degradable cystine crosslinker, and were synthesized by applying precipitation polymerization. Such way of polymerization was appropriately modified to limit the crosslinking in the microcapsule center. This led to a possibility of washing out the pNIPA core at room temperature and the formation of a capsule. Microcapsules revealed rather high drug-loading capacity of ca. 17%. The degradation of the microcapsules by the reducing agent (GSH) and the oxidizing agent (H2O2) was confirmed by using the DLS, UV-Vis, SEM and TEM techniques. Depending on pH and concentration of the reducing/oxidizing agents a fast or slow degradation of the microcapsules and a burst or long-term release of doxorubicin (DOX) were observed. The DOX loaded microcapsules appeared to be cytotoxic against A2780 cancer cells similarly to DOX alone, while unloaded microcapsules did not inhibit proliferation of the cells.

Determination of the properties and loading efficiency of encapsulated BSA-FITC and dexamethasone for drug delivery systems

In this work porous microparticles of calcium carbonate were synthesized with bovine serum albumin - fluorescein isothiocyanate conjugate (BSA-FITC) and dexamethasone, and then used for encapsulation in polymer microcapsules by means of layer-by-layer assembly (LbL). The properties of the obtained microcapsules were characterized by scanning electron microscopy, dynamic light scattering, infrared-, ultraviolet- and visible spectroscopy. According to the performed DLS measurements, an average hydrodynamic diameter ranged from 4 to 8 µm and zeta-potential for all types of capsules was determined as -18 and -21 mV. BSA-FITC was encapsulated using this approach yielded a loading efficiency of 49 % protein. This value calculated for dexamethasone was of 38%. The microcapsules filled with an encapsulated drug may find applications in the field of biotechnology, biochemistry, and medicine.

Polymeric hollow microcapsules (PHM) via cellulose nanocrystal stabilized Pickering emulsion polymerization

A practical and sustainable method to prepare polymeric hollow microcapsules (PHMs) using cellulose nanocrystal (CNC) stabilized Pickering emulsion polymerization was developed. Pristine CNCs hydrolyzed from wood pulp are hydrophilic and could be employed as emulsifiers to prepare oil-in-water (O/W) Pickering emulsions. The O/W Pickering emulsions were used as templates for the Pickering emulsion polymerization of hydrophobic monomers inside the emulsion droplets. The crosslinked hydrophobic polymers phase separated and partitioned to the interface of the Pickering emulsion, leading to the formation of hydrophobic PHMs. Correspondingly, cinnamate modified CNCs with less surface hydrophilicity were employed as emulsifiers to obtain water-in-oil (W/O) inverse Pickering emulsions, which were then used as templates for inverse Pickering emulsion polymerization of hydrophilic monomers to prepare hydrophilic PHMs. Therefore, both hydrophobic and hydrophilic PHMs could be obtained via this approach. Herein, polystyrene, poly(4-vinylpyridine), and poly(N-isopropyl acrylamide) hollow microcapsules were prepared as models, where the size, crosslinking density, shell structure and stimuli-responsive properties of PHMs could be tuned by varying the synthesis parameters.

Chitosan microcapsule membranes with nanoscale thickness for controlled release of drugs

In this paper, chitosan microcapsules with stable nano-membranes for controlled release of drugs are prepared by a simple one-step microfluidic strategy from oil-in-water (O/W) single emulsion templates. The ultrathin membranes of microcapsules are formed at the interface of the O/W emulsion droplets via the interfacial reaction between chitosan in aqueous phase and terephthalaldehyde in oil core. The membrane thickness can be effectively controlled within 10 nm and accurately regulated at nanoscale from 2.8 nm to 8.0 nm by adjusting the crosslinking time, concentrations of reactant and viscosity of aqueous solution. Among these factors, the membrane thickness is more susceptible to the viscosity of aqueous phase. The stability of the nano-membranes is quite good, which makes the microcapsules exhibit excellent structure integrity during 150 days. Using tea tree oil (TTO) as the model drug, the prepared chitosan microcapsules with nano-membranes show low mass transfer resistance and rapid drug release. The cumulative release rate of TTO from chitosan microcapsules with membrane thickness of 3.1 nm and 4.3 nm reach to 76.1% and 56.6% within 10 h, respectively. The drug release behaviors from the chitosan microcapsules are directly related to the thickness of the capsule membranes, and therefore can also be finely controlled. The thinner the capsule membrane is, the faster the drug release. The initial TTO release rate doubles as the membrane thickness decreases from 4.3 nm to 3.1 nm. In addition, because no surfactant is used in the whole preparation process, the prepared chitosan microcapsules present satisfactory biocompatibility. The results provide valuable guidance for designing and fabricating polymeric microcapsule membranes with controllable nanoscale thickness to enhance their performances in biological and medical applications.

Ultrasound-triggered release from metal shell microcapsules

Metal shell microcapsules have been shown to completely retain their core until its release is triggered, making them a promising candidate for use as a controllable drug delivery vehicle due to their superior retention properties as compared to polymer shell microcapsules. Focused ultrasound (FUS) has been successfully utilised to trigger release of lipophilic drugs from polymer microcapsules, and in this work the response of gold shell microcapsules with and without an inner polymeric shell, to FUS and standard ultrasound is explored. The results show that gold shell microcapsules with an inner polymer shell rupture when exposed to standard ultrasound and that there is a linear correlation between the gold shell thickness and the extent of shell rupture. When FUS is applied to these microcapsules, powers as low as 0.16 W delivered in bursts of 10 ms/s over a period of 120 s are sufficient to cause rupture of 53 nm gold shell microcapsules. Additional findings suggest that gold shell microcapsules without the polymer layer dispersed in a hydrogel matrix, as opposed to aqueous media, rupture more efficiently when exposed to FUS, and that thicker gold shells are more responsive to ultrasound-triggered rupture regardless of the external environment. Release of dye from all successfully ruptured capsules was sustained over a period of between 7 and 35 days. These findings suggest that emulsion-templated gold shell microcapsules embedded in a hydrogel matrix would be suitable for use as an implantable drug delivery vehicle with FUS used to externally trigger release.

Magnetic polymer microcapsules: One-step template/surfactant-free preparation and Pt decoration for catalytic reduction of aromatic nitro compounds

Rapid and scalable preparation of polymer-based magnetic microcapsules (MMCs) without employing any templates and surfactants is still a challenge. Herein, we present a one-step template/surfactant-free strategy for fast and large-scale fabrication of poly(vinyl alcohol) (PVA)-based MMCs. The MMCs are formed from simultaneous creation of magnetic Fe3O4 nanoparticles and crosslinking of PVA chains, which is achieved by simple addition of ammonia solution into the preformed water-in-oil (W/O) emulsion comprising castor oil, aqueous mixture of PVA and iron salts. The size and shell thickness of MMCs could be readily controlled by fine tuning the process parameters. Furthermore, this approach allows for incorporation of additional functional nanoparticles into the PVA shell of MMCs, as demonstrated by the fabrication of Pt nanoparticles decorated MMCs (Pt-MMCs) in this study. The Pt-MMCs displayed favorable catalytic activity for reduction of aromatic nitro compounds (e.g., 4-nitrophenol and 4-nitroaniline), and could be conveniently recycled using magnet and reused for > ten times without obvious decline of catalytic activity. This work thus opens a new pathway for facile fabrication of property-tailored MMCs to meet the requirements of various applications.

Electrodeposition of Ginseng/Polyaniline Encapsulated Poly(lactic-co-glycolic Acid) Microcapsule Coating on Stainless Steel 316L at Different Deposition Parameters.

Electrodeposition is commonly used to deposit ceramic or metal coating on metallic implants. Its utilization in depositing polymer microcapsule coating is currently being explored. However, there is no encapsulation of drug within polymer microcapsules that will enhance its chemical and biological properties. Therefore, in this study, ginseng which is known for its multiple therapeutic effects was encapsulated inside biodegradable poly(lactic-co-glycolic acid) (PLGA) microcapsules to be coated on pre-treated medical grade stainless steel 316L (SS316L) using an electrodeposition technique. Polyaniline (PANI) was incorporated within the microcapsules to drive the formation of microcapsule coating. The electrodeposition was performed at different current densities (1-3 mA) and different deposition times (20-60 s). The chemical composition, morphology and wettability of the microcapsule coatings were characterized through attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM) and contact angle analyses. The changes of electrolyte colors, before and after the electrodeposition were also observed. The addition of PANI has formed low wettability and uniform microcapsule coatings at 2 mA current density and 40 s deposition time. Reduction in the current density or deposition time caused less attachment of microcapsule coatings with high wettability records. While prolonging either one parameter has led to debris formation and melted microcapsules with non-uniform wettability measurements. The color of electrolytes was also changed from milky white to dark yellow when the current density and deposition time increased. The application of tolerable current density and deposition time is crucial to obtain a uniform microcapsule coating, projecting a controlled release of encapsulated drug.

Controlling the internal morphology of aqueous core-PLGA shell microcapsules: promoting the internal phase separation via alcohol addition

The ability to control the internal core architecture of polymeric microcapsules has a direct impact on their applications. However, this task, especially to produce microcapsules with a high percentage of mononuclear aqueous cores, proved to be challenging. In this work, and in continuation to our previous studies, we report a facile protocol to prepare poly(D,L-lactide-co-glycolide) (PLGA) microcapsules with unprecedented percentage (almost 100%) of mononuclear aqueous cores by the internal phase separation method via adding alcohols. Different types of alcohols (methanol, ethanol, propanol, isopropanol, butanol, and octanol) were incorporated into the internal phase solution and then emulsified into mineral oil. In situ monitoring of emulsion droplets was performed by phase contrast microscopy at different time points and the percentage of mononuclear droplets was measured. While alcohol-free formulation ended up with only around 51% of mononuclear microcapsules, incorporating alcohols resulted in the formation of more than 90% of mononuclear microcapsules. Octanol, in particular, exhibited an outstanding performance as its incorporation led to an immediate (at 0 h) formation of almost entirely mononuclear microcapsules. Final microcapsules exhibited spherical shape with mean particle size in the range of 1–2 µm as depicted by scanning electron microscopy and dynamic light scattering analysis.

A Facile Route to Prepare PMMA/SiO2 Core‐Shell Particles and PMMA Microcapsules via Sonochemical Graft Polymerization

AbstractUltrasonically initiated graft polymerization is employed to prepare poly (methyl methacrylate)/silicon dioxide (PMMA/SiO2) core‐shell particles and PMMA microcapsules. Monodisperse SiO2 particles are obtained by the Stöber method. Its surface is modified with γ‐methacryloxypropyl trimethoxy silane (MPS) to introduce unsaturated double bonds. And then MMA and MPS are copolymerized under ultrasonic initiation to prepare PMMA/SiO2 core‐shell particles. PMMA microcapsules are obtained by etching SiO2 with the HF aqueous solution. The morphology and size of the core‐shell particles and polymer microcapsules are analysed using transmission electron microscopy (TEM) and dynamic light scattering (DLS). The encapsulation state is determined using a Fourier transform infrared spectrometer (FTIR) and X‐ray photoelectron spectrometer (XPS). The results show that both the core‐shell particles and the polymer microcapsules have perfect core‐shell or hollow structures. The control of shell thickness can be easily realized by adjusting the amount of monomer, e. g. 30 nm, 50 nm and 80 nm, respectively. And in the inner of the shell, PMMA is anchored onto the surface of SiO2 core with covalent bonds. As the monomer amount increases, the contents of Si, O, and C change accordingly. And the polymer shell would become denser and thicker.

Tribological behavior of polymer composites functionalized with various microcapsule core materials

Severe abrasion wear of water-lubricated bearings usually occurs during low-speed and heavy-duty working conditions. It is vital to improve the anti-friction and tribological properties of the composites used in the water-lubricated bearings. In this reported work, polymer microcapsules were added to matrix material as compositional modifications, to improve the tribological properties of the bearing as it was worn against a cast copper bushing. These microcapsules appeared to reduce the phase splitting between the low-melting-point lubricant and the matrix. In this particular study, urea formaldehyde (UF) microcapsules loaded with two lubricants included N, N′-ethylene Bis-stearamide and Erucic Amide as core materials were synthesized by double emulsion method (w/o/w) and then blended with high-density polyethylene (HDPE) to form the composites. The tribological properties of the microcapsule-modified composites were investigated using a CBZ-1 tribometer under different running conditions. After testing, the microcapsules were characterized using Fourier Transform Infrared Spectroscopy (FTIR) and the surface morphologies of composites were analyzed by using Scanning Electron Microscopy (SEM). The analytical results revealed that the tribological properties of the composites were improved as the quantity of microcapsules in the composite was increased. The composites containing the microcapsules produced lower sliding friction and exhibited a smoother surface morphology, which was due to the lubrication provided by the Erucic Amide in the microcapsules. As shell of microcapsules was worn away during the test, the encapsulated Erucic Amide was released into the friction pairs, which established a dense lubrication film. When the mass fraction of the Erucic Amide containing microcapsules is 10 wt%, the frictional coefficient of composites is reduced by 66.9% under low sliding velocity and middling applied load conditions. This study also provided an experimental basis for the structural design and performance enhancement of water-lubricated bearings.

Evolution of Self-Organized Microcapsules with Variable Conductivities from Self-Assembled Nanoparticles at Interfaces.

Self-organization dramatically affects the surface properties of materials on a macroscopic scale, such as wettability and adhesion. Fundamentally, it is equally interesting when self-organization at the nanoscale affects the bulk properties and thus provides a means to engineer the optoelectronic properties of the materials on larger scales. In this work, we report the evolution of conductive self-organized polymer microcapsules from a monomer emulsion droplet stabilized by a monolayer of conductive Janus nanoparticles (JNPs) via a mechanism resembling morphogenesis. The wall of the resulting conductive microcapsule has a honeycomb-like structure with highly oriented JNPs occupying each hollow cell. The JNPs consist of an electrically conductive lobe and an insulating lobe; because of their orientation and presence in the honeycomb, the conductivity of the microcapsule is greatly enhanced as compared to that of each of the constituting materials. This method can be universally applied to induce self-organization in conductive polymers forming by oxidative addition.

Characterization of CDNF-Secreting ARPE-19 Cell Clones for Encapsulated Cell Therapy

Cerebral dopamine neurotrophic factor (CDNF) shows beneficial effects in rodent models of Parkinson’s and Alzheimer’s disease. The brain is a challenging target for protein therapy due to its exclusive blood–brain barrier. Hence, the therapeutic protein should be delivered directly to the brain parenchyma. Implantation of encapsulated mammalian cells that constantly secrete CDNF is a potential approach for targeted and long-term protein delivery to the brain. In this study, we generated several CDNF-secreting cell clones derived from human retinal pigment epithelial cell line ARPE-19, and studied CDNF secretion from the clones maintained as monolayers and in polymeric microcapsules. The secretion of wild type (wt) CDNF transgene was low and the majority of the produced protein remained intracellular, locating mainly to the endoplasmic reticulum (ER). The secretion of wtCDNF decreased to even lower levels when the clones were in a non-dividing state, as in the microcapsules. Both codon optimization and deletion of the putative ER-retrieval signal (four last amino acids: KTEL) improved CDNF secretion. More importantly, the secretion of KTEL-deleted CDNF remained constant in the non-dividing clones. Thus, cells expressing KTEL-deleted CDNF, in contrast to wtCDNF, can be considered for cell encapsulation applications if the KTEL-deleted CDNF is proven to be biologically active in vivo.

Highly-efficient and selective adsorption of anionic dyes onto hollow polymer microcapsules having a high surface-density of amino groups: Isotherms, kinetics, thermodynamics and mechanism

Organic dye pollution in the water environment is a problem of global concern. Adsorption is demonstrated as a promising technology to remove organic dyes from wastewater, in which the development of highly-efficient adsorbents is still the challenging task. Herein, we reported the facile fabrication of polyamine-based cyclophosphazene hybrid (PCP-NH2) hollow microcapsules with cross-linked structure, generated by one-step precipitation polymerization between hexachlorocyclotriphosphazene and branched polyethyleneimine, and subsequent acetone treatment. Their morphology, composition and structure were confirmed by SEM, TEM, FTIR, TGA, and XPS. The endowment of hollow PCP-NH2 microcapsules as potential adsorbents were thoroughly evaluated using eight organic dyes with different surface charges. The adsorption action of hollow PCP-NH2 microcapsules highly depends on the surfaces charges, exhibiting highly-efficient and selective adsorption behavior towards anionic dyes. Especially, The adsorption capacity of the hollow PCP-NH2 microcapsules towards anionic dyes of EY, ACBK, MO and EB reaches up to 1196.36, 1190.65, 1142.77 and 1040.92 mg/g at 25 °C, respectively. The adsorption kinetics shows a better fit to pseudo second-order kinetic model, compared to pseudo-first-order kinetic and Weber’s intraparticle diffusion models. The adsorption equilibrium data followed the Langmuir isotherm well. The adsorption thermodynamic experiments demonstrated that adsorption was a physisorption process with endothermic and spontaneous characteristic.

Sustainable removal of pernicious arsenic and cadmium by a novel composite of MnO2 impregnated alginate beads: A cost-effective approach for wastewater treatment

There is a dire necessity of developing low cost waste water treatment systems, for the efficient removal of noxious heavy metals (and metalloids) such as Arsenic (As) and Cadmium (Cd). Magnetic biopolymer (CABs-MO) was synthesized by the entrapment of nanocrystalline MnO2 in the polymeric microcapsules of calcium alginate (CABs). Batch experiments were conducted under constant pH (6.5), temperature (25OC), different initial concentrations (30–300 mg L−1) and contact times (0–48 h) to study the adsorption isotherms and removal kinetics of pristine (CABs) and hybrid biopolymer (CABs-MO) for the removal of As and Cd. The pseudo-equilibrium process was mathematically well explained by the pseudo-second-order kinetic (R2 ≥ 0.99) and Langmuir isotherm model (R2 ≥ 0.99) with the highest monolayer sorption capacity of 63.6 mg g−1 for Cd on CABs-MO. The As removal rate was maximum up to 6.5 mg g−1 after 12 h of contact period in a single contaminant system than in the mixed contaminant (As + Cd) system (0.8 mg g−1), though the effect was non-significant for Cd (p < 0.05; t-test). The performance of the 10 mM HCl as a regenerating agent was superior (for As in comparison to Cd, p < 0.05; t-test) compared to distilled water (DW) through three to five regeneration cycles. Therefore, the obtained results clearly validate the feasibility of CABs-MO as a potential promising adsorbent for removing metal contaminants from the wastewater. Further research is required to study the decontamination of emerging contaminants with such novel composite beads characterized by varied physico-chemical properties.

The effects of Al surface treatment, adhesive thickness and microcapsule inclusion on the shear strength of bonded joints

The influences of various Al surface treatments, adhesive thicknesses as well as the incorporation of synthesized microcapsules into epoxy adhesive on the shear strength of adhesive/ Al joints have been investigated using lap-shear tensile tests. First, the influence of adhesive thickness on the shear strength of joints has been presented. Then, the effects of various Al surface treatments on the surface roughness of Al and shear strength of joint have been researched. Atomic force microscopy was used to study the Al surface morphologies and textures. Finally the few micron-sized polymeric microcapsules were synthesized and the shear performances of microcapsule filled epoxy adhesives were inspected. It was observed that the HCl acid based etching increased both micro-roughness and nano-texture of the Al surface and led to the peak shear strength. Moreover, HCl-nitric acid treatment offered the maximum value for the cohesive failure. Capsule inclusions into the adhesive displayed different influences on the joint shear performances depending on the capsule morphology and the surface treatment of Al.

Development of sustainable concrete repair materials via microencapsulated agents

Identification of non-structural damage in concrete infrastructure and actuation of preventive repair solutions is an established approach to avoid further structural damages and more expensive repair regimes. However the repair of concrete itself is not infallible with 55% of reported repairs in the EU failing within 5 years of service. Thus the already once repaired concrete structure is then subject to a constant cycle of repeated repair and a cumulative associated life cycle cost. The development of external repair material with self-healing capabilities, can affect a real step-change on the life-cycle costs and maintenance of existing and new infrastructure. Developed polymeric microcapsules containing liquid sodium silicate were used to impart autonomic self-healing to readily available commercial repair mortars for the first time. These materials cover a range of potential real time repair applications. Initially the compatibility between the developed self-healing agents and commercial products was established and the self-healing performance of the novel composite system was then evaluated. The results underlined the huge potential for the proposed composite systems as a stepping stone toward commercial uptake of self-healing microcapsule-based cementititious materials.

Ortho-substituted azobenzene: shedding light on new benefits

Abstract Novel functional polymeric microcapsules, based on modified azobenzene moieties, are exhaustively investigated, both from a theoretical and experimental points of view. Theoretical calculations and several measurements demonstrate that visible light can act as a trigger for release of encapsulated material, as a consequence of trans-cis isomerization which modifies microcapsule surface topography and can induce a “squeezing” release mechanism. Interfacial polymerization of an oil-in-water emulsion is performed and leads to core-shell microcapsules which are characterized by means of atomic force microscopy (AFM), optical microscopy (OM), scanning electron microscopy (SEM) and light scattering. These analyses put into evidence that microcapsules’ size and surface morphology are strongly affected by irradiation under visible light: moreover, these changes can be reverted by sample exposure to temperatures around 50°C. This last evidence is also confirmed by NMR kinetic analyses on modified azobenzene moiety. Finally, it is shown that these smart microcapsules can be successfully used to get a controlled release of actives such as fragrancies, as a consequence of visible light irradiation, as confirmed by an olfactive panel.

Assembly Controlled by Shape

ABSTRACTTo research the impact of the shape on the assembly of the natural objects (protein, virus, bacteria, living cells) the polymer microcapsules with similar surface chemistry and different by shape (spherical, cubical and tetrahedral) had been synthesized. It was found that the energetically favourable face-to-face attachment of anisotropic microcapsules drives the formation of stable and compacted assembly while isotropic microcapsules assembly is mobile and chain-like structures with a point like a contact area. The difference in assembling behaviour of anisotropic (cubic, tetrahedral) and isotropic (spherical) microparticles is related to the fact that the interfacial hydrophobic energies between the anisotropic microparticles are 6-4 orders of magnitude higher than that for the isotropic microparticles due to the significantly higher contact area of anisotropic microparticles. Such mimicking of the natural objects by polymer microcapsules and research their interaction driven by shape explains the arrangements of isotropic and anisotropic cells in bacteria and its mobility.

RETRACTED: Production, characterization and controlled release studies of biodegradable polymer microcapsules incorporating neem seed oil by spray drying

Abstract Azadirachtin is a biologically active constituent of neem seed oil, exhibiting medicinal and pesticidal properties. This work reports on the encapsulation of neem seed oil extract within three different polymeric shells: polyvinyl alcohol (PVA), gum arabic (GA) and whey protein isolate/maltodextrin (WPI/MD), using spray drying. The obtained, roughly spherical microcapsules had average sizes of 28.84 ± 11.86 μm, 32.43 ± 13.06 μm, and 52.88 ± 17.33 μm (obtained from PVA, GA, and WPI/MD, respectively). Fourier transform infrared spectroscopy confirmed the presence of the core and shell components, in addition to surface functional groups. Encapsulation efficiencies for neem seed oil proved higher in smaller microcapsules, although efficiency values of 60–92% were obtained in all cases. In vitro release of neem seed oil from the microcapsules followed the Ritger–Peppas model, as governed by Fickian diffusion. From these results, the association of botanical insecticides within biopolymer cores offer considerable potential for increasing agricultural production levels, and reducing impacts on the environment and human health.

Disruption of Polymer and Composite Microcapsule Shells under High-Intensity Focused Ultrasound

A process has been described for obtaining polymer (polyelectrolyte) microcapsules and polyelectrolyte/magnetite composite microcapsules, as well as silica-based hybrid capsules via silane-type precursor hydrolysis, which gives rise to the formation of silica nanoparticles in the structures of shells containing different numbers of polymer layers. The polymer and nanocomposite microcapsules have been formed by successive adsorption of oppositely charged polyelectrolytes and/or nanoparticles on the surface of microparticles of vaterite, which is a polymorphous modification of calcium carbonate. The obtained shells of microcapsules of all types have been studied by atomic force microscopy, confocal fluorescence microscopy, and scanning electron microscopy before and after sonication. The effect of high-intensity focused ultrasound on the obtained samples of microcapsules has been investigated and the sonication parameters that ensure efficient disruption of their shells in an aqueous medium have been determined. It has been found that composite microcapsules containing magnetite nanoparticles in their shells are most sensitive to sonication. The obtained composite microcapsules are promising for developing new systems for delivery of biologically active substances and multifunctional coatings.