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Function of Polymers in Encapsulation Process

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A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Polymer Processing and Engineering".

Deadline for manuscript submissions: closed (31 December 2021) | Viewed by 46118

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Special Issue Editors

Dr. M. Ali Aboudzadeh

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Guest Editor

1. Centro de Física de Materiales, CSIC-UPV/EHU, Paseo Manuel Lardizábal 5, 20018 Donostia-San Sebastián, Spain
2. Donostia International Physics Center (DIPC), Paseo Manuel Lardizábal 4, 20018 Donostia-San Sebastián, Spain
Interests: polymer synthesis and characterization; supramolecular assemblies; rheology; DNA nanotechnology; encapsulation via emulsion-based systems; polymer hybrid materials
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Dr. Shaghayegh Hamzehlou

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POLYMAT and Kimika Aplikatua Saila, Kimika Fakultatea, University of the Basque Country UPV-EHU, Joxe Mari Korta Zentroa, Tolosa Hiribidea 72, 20018 Donostia-San Sebastian, Spain
Interests: polymer reaction engineering; modelling and simulation of kinetics, topology, microstructure and morphology of the complex polymerization systems; emulsion polymerization; polymer synthesis and characterization

Special Issue Information

Dear Colleagues,

Encapsulation technology consists of surrounding active agents within a homogeneous/heterogeneous matrix at the micro/nano scale. Using this technology, a physical barrier is developed between the inner substance and the environment which prevents its degradation and facilitates its handling and transportation. Polymers may be used to trap the material of interest inside the micro/nano-capsules. Such encapsulated systems have many applications in the fields of food industry, drug delivery, agriculture, cosmetics, coatings, adhesives and so forth. There are a number of chemical, physical or mechanical processes available for encapsulation such as emulsion-solvent evaporation/extraction methods, coacervation-phase separation, spray drying, interfacial and in situ polymerization. The choice of a particular technique depends on the attributes of the polymer and the active agent. There are still many aspects to be developed in this field, which offer new challenges and breakthrough opportunities. The main objective of this interdisciplinary Special Issue is to bring together, at an international level, a high-quality collection of reviews, original articles and short communications dealing with the importance of natural or synthetic polymers in encapsulation processes and their applications.

We review all the articles in our Special Issue, and we believe this editorial will interest the broadest possible section of readership among materials scientists and engineers.

Dr. M. Ali Aboudzadeh
Dr. Shaghayegh Hamzehlou
Guest Editors

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Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Polymers is an international peer-reviewed open access semimonthly journal published by MDPI.

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Keywords

encapsulation technology
drug delivery
nanoparticles
nanocapsules
microcapsules
biodegradable polymers
emulsion polymerization
biomedical applications
spray-drying
biomaterials

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Published Papers (13 papers)

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Editorial

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4 pages, 184 KiB

Open AccessEditorial

Special Issue on “Function of Polymers in Encapsulation Process”

by M. Ali Aboudzadeh and Shaghayegh Hamzehlou

Polymers 2022, 14(6), 1178; https://doi.org/10.3390/polym14061178 - 15 Mar 2022

Cited by 5 | Viewed by 1845

Abstract

Encapsulation technology comprises enclosing active agents (core materials) within a homogeneous/heterogeneous matrix (wall material) at the micro/nano scale [...] Full article

(This article belongs to the Special Issue Function of Polymers in Encapsulation Process)

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15 pages, 2404 KiB

Open AccessArticle

Enhanced Dissolution of Sildenafil Citrate Using Solid Dispersion with Hydrophilic Polymers: Physicochemical Characterization and In Vivo Sexual Behavior Studies in Male Rats

by Mohammed F. Aldawsari, Md. Khalid Anwer, Mohammed Muqtader Ahmed, Farhat Fatima, Gamal A. Soliman, Saurabh Bhatia, Ameeduzzafar Zafar and M. Ali Aboudzadeh

Polymers 2021, 13(20), 3512; https://doi.org/10.3390/polym13203512 - 13 Oct 2021

Cited by 15 | Viewed by 2954

Abstract

Sildenafil citrate (SLC) is a frequently used medication (Viagra®) for the treatment of erectile dysfunction (ED). Due to its poor solubility, SLC suffers from a delayed onset of action and poor bioavailability. Hence, the aim of the proposed work was to prepare and evaluate solid dispersions (SDs) with hydrophilic polymers (Kolliphor® P188, Kollidon® 30, and Kollidon®-VA64), in order to enhance the dissolution and efficacy of SLC. The SLC-SDs were prepared using a solvent evaporation method (at the ratio drug/polymer, 1:1, w/w) and characterized by Differential Scanning Calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscope (SEM), drug content, yield, and in vitro release studies. Based on this evaluation, SDs (SLC-KVA64) were optimized, with a maximum release of drug (99.74%) after 2 h for all the developed formulas. The SDs (SLC-KVA64) were further tested for sexual behavior activity in male rats, and significant enhancements in copulatory efficiency (81.6%) and inter-copulatory efficiency (44.9%) were noted in comparison to the pure SLC drug, when exposed to the optimized SLC-KVA64 formulae. Therefore, SD using Kollidon®-VA64 could be regarded as a potential strategy for improving the solubility, in vitro dissolution, and therapeutic efficacy of SLC. Full article

(This article belongs to the Special Issue Function of Polymers in Encapsulation Process)

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18 pages, 35879 KiB

Open AccessArticle

Development and Evaluation of Polyvinylpyrrolidone K90 and Poloxamer 407 Self-Assembled Nanomicelles: Enhanced Topical Ocular Delivery of Artemisinin

by Chandrasekar Ponnusamy, Abimanyu Sugumaran, Venkateshwaran Krishnaswami, Rajaguru Palanichamy, Ravichandiran Velayutham and Subramanian Natesan

Polymers 2021, 13(18), 3038; https://doi.org/10.3390/polym13183038 - 8 Sep 2021

Cited by 15 | Viewed by 3988

Abstract

Age-related macular degeneration is a multifactorial disease affecting the posterior segment of the eye and is characterized by aberrant nascent blood vessels that leak blood and fluid. It ends with vision loss. In the present study, artemisinin which is poorly water-soluble and has potent anti-angiogenic and anti-inflammatory properties was formulated into nanomicelles and characterized for its ocular application and anti-angiogenic activity using a CAM assay. Artemisinin-loaded nanomicelles were prepared by varying the concentrations of PVP k90 and poloxamer 407 at different ratios and showed spherical shape particles in the size range of 41–51 nm. The transparency and cloud point of the developed artemisinin-loaded nanomicelles was found to be 99–94% and 68–70 °C, respectively. The in vitro release of artemisinin from the nanomicelles was found to be 96.0–99.0% within 8 h. The trans-corneal permeation studies exhibited a 1.717–2.169 µg permeation of the artemisinin from nanomicelles through the excised rabbit eye cornea for 2 h. Drug-free nanomicelles did not exhibit noticeable DNA damage and showed an acceptable level of hemolytic potential. Artemisinin-loaded nanomicelles exhibited remarkable anti-angiogenic activity compared to artemisinin suspension. Hence, the formulated artemisinin-loaded nanomicelles might have the potential for the treatment of AMD. Full article

(This article belongs to the Special Issue Function of Polymers in Encapsulation Process)

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14 pages, 2782 KiB

Open AccessArticle

Design of Olmesartan Medoxomil-Loaded Nanosponges for Hypertension and Lung Cancer Treatments

by Bjad K. Almutairy, Abdullah Alshetaili, Amer S. Alali, Mohammed Muqtader Ahmed, Md. Khalid Anwer and M. Ali Aboudzadeh

Polymers 2021, 13(14), 2272; https://doi.org/10.3390/polym13142272 - 11 Jul 2021

Cited by 46 | Viewed by 4541

Abstract

Olmesartan medoxomil (OLM) is one of the prominent antihypertensive drug that suffers from low aqueous solubility and dissolution rate leading to its low bioavailability. To improve the oral bioavailability of OLM, a delivery system based on ethylcellulose (EC, a biobased polymer) nanosponges (NSs) was developed and evaluated for cytotoxicity against the A549 lung cell lines and antihypertensive potential in a rat model. Four OLM-loaded NSs (ONS1-ONS4) were prepared and fully evaluated in terms of physicochemical properties. Among these formulations, ONS4 was regarded as the optimized formulation with particle size (487 nm), PDI (0.386), zeta potential (ζP = −18.1 mV), entrapment efficiency (EE = 91.2%) and drug loading (DL = 0.88%). In addition, a nanosized porous morphology was detected for this optimized system with NS surface area of about 63.512 m²/g, pore volume and pore radius Dv(r) of 0.149 cc/g and 15.274 Å, respectively, measured by nitrogen adsorption/desorption analysis. The observed morphology plus sustained release rate of OLM caused that the optimized formulation showed higher cytotoxicity against A549 lung cell lines in comparison to the pure OLM. Finally, this system (ONS4) reduced the systolic blood pressure (SBP) significantly (p < 0.01) as compared to control and pure OLM drug in spontaneously hypertensive rats. Overall, this study provides a scientific basis for future studies on the encapsulation efficiency of NSs as promising drug carriers for overcoming pharmacokinetic limitations. Full article

(This article belongs to the Special Issue Function of Polymers in Encapsulation Process)

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11 pages, 2479 KiB

Open AccessCommunication

In-Situ One-Step Direct Loading of Agents in Poly(acrylic acid) Coating Deposited by Aerosol-Assisted Open-Air Plasma

by Gabriel Morand, Pascale Chevallier, Cédric Guyon, Michael Tatoulian and Diego Mantovani

Polymers 2021, 13(12), 1931; https://doi.org/10.3390/polym13121931 - 10 Jun 2021

Cited by 5 | Viewed by 2754

Abstract

In biomaterials and biotechnology, coatings loaded with bioactive agents are used to trigger biological responses by acting as drug release platforms and modulating surface properties. In this work, direct deposition of poly(acrylic acid) coatings containing various agents, such as dyes, fluorescent molecules, was achieved by aerosol-assisted open-air plasma. Using an original precursors injection strategy, an acrylic acid aerosol was loaded with an aqueous aerosol and deposited on silicon wafers. Results clearly showed that agents dissolved in the aqueous aerosol were successfully entrapped in the final coating. The effect of aerosols concentration, flow rate, and treatment time, on the coating morphology and the amount of entrapped agents, was also investigated. It was demonstrated that this process has the potential to entrap a tunable amount of any sensible water-soluble agent without altering its activity. To the best of our knowledge, this is the first time that the loading of an aqueous aerosol in coatings deposited by plasma from a liquid aerosol precursor is reported. This innovative approach complements plasma deposition of coatings loaded with bioactive agents from aqueous aerosols with the use of non-volatile liquid precursors. Full article

(This article belongs to the Special Issue Function of Polymers in Encapsulation Process)

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11 pages, 2854 KiB

Open AccessArticle

Polyethyleneimine-Oleic Acid Micelles-Stabilized Palladium Nanoparticles as Highly Efficient Catalyst to Treat Pollutants with Enhanced Performance

by Xiang Lai, Xuan Zhang, Shukai Li, Jie Zhang, Weifeng Lin and Longgang Wang

Polymers 2021, 13(11), 1890; https://doi.org/10.3390/polym13111890 - 6 Jun 2021

Cited by 4 | Viewed by 2691

Abstract

Water soluble organic molecular pollution endangers human life and health. It becomes necessary to develop highly stable noble metal nanoparticles without aggregation in solution to improve their catalytic performance in treating pollution. Polyethyleneimine (PEI)-based stable micelles have the potential to stabilize noble metal nanoparticles due to the positive charge of PEI. In this study, we synthesized the amphiphilic PEI-oleic acid molecule by acylation reaction. Amphiphilic PEI-oleic acid assembled into stable PEI-oleic acid micelles with a hydrodynamic diameter of about 196 nm and a zeta potential of about 34 mV. The PEI-oleic acid micelles-stabilized palladium nanoparticles (PO-PdNPs_n) were prepared by the reduction of sodium tetrachloropalladate using NaBH₄ and the palladium nanoparticles (PdNPs) were anchored in the hydrophilic layer of the micelles. The prepared PO-PdNPs_n had a small size for PdNPs and good stability in solution. Noteworthily, PO-PdNPs₁₅₀ had the highest catalytic activity in reducing 4-nitrophenol (4-NP) (K_nor = 18.53 s⁻¹mM⁻¹) and oxidizing morin (K_nor = 143.57 s⁻¹M⁻¹) in aqueous solution than other previous catalysts. The enhanced property was attributed to the improving the stability of PdNPs by PEI-oleic acid micelles. The method described in this report has great potential to prepare many kinds of stable noble metal nanoparticles for treating aqueous pollution. Full article

(This article belongs to the Special Issue Function of Polymers in Encapsulation Process)

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10 pages, 1516 KiB

Open AccessArticle

Application of Redox-Responsive Hydrogels Based on 2,2,6,6-Tetramethyl-1-Piperidinyloxy Methacrylate and Oligo(Ethyleneglycol) Methacrylate in Controlled Release and Catalysis

by Miriam Khodeir, He Jia, Alexandru Vlad and Jean-François Gohy

Polymers 2021, 13(8), 1307; https://doi.org/10.3390/polym13081307 - 16 Apr 2021

Cited by 5 | Viewed by 2460

Abstract

Hydrogels have reached momentum due to their potential application in a variety of fields including their ability to deliver active molecules upon application of a specific chemical or physical stimulus and to act as easily recyclable catalysts in a green chemistry approach. In this paper, we demonstrate that the same redox-responsive hydrogels based on polymer networks containing 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) stable nitroxide radicals and oligoethylene glycol methyl ether methacrylate (OEGMA) can be successfully used either for the electrochemically triggered release of aspirin or as catalysts for the oxidation of primary alcohols into aldehydes. For the first application, we take the opportunity of the positive charges present on the oxoammonium groups of oxidized TEMPO to encapsulate negatively charged aspirin molecules. The further electrochemical reduction of oxoammonium groups into nitroxide radicals triggers the release of aspirin molecules. For the second application, our hydrogels are swelled with benzylic alcohol and tert-butyl nitrite as co-catalyst and the temperature is raised to 50 °C to start the oxidation reaction. Interestingly enough, benzaldehyde is not miscible with our hydrogels and phase-separate on top of them allowing the easy recovery of the reaction product and the recyclability of the hydrogel catalyst. Full article

(This article belongs to the Special Issue Function of Polymers in Encapsulation Process)

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16 pages, 17737 KiB

Open AccessArticle

Enhancement of the Thermal Performance of the Paraffin-Based Microcapsules Intended for Textile Applications

by Virginija Skurkyte-Papieviene, Ausra Abraitiene, Audrone Sankauskaite, Vitalija Rubeziene and Julija Baltusnikaite-Guzaitiene

Polymers 2021, 13(7), 1120; https://doi.org/10.3390/polym13071120 - 1 Apr 2021

Cited by 38 | Viewed by 3532

Abstract

Phase changing materials (PCMs) microcapsules MPCM32D, consisting of a polymeric melamine-formaldehyde (MF) resin shell surrounding a paraffin core (melting point: 30–32 °C), have been modified by introducing thermally conductive additives on their outer shell surface. As additives, multiwall carbon nanotubes (MWCNTs) and poly (3,4-ethylenedioxyoxythiophene) poly (styrene sulphonate) (PEDOT: PSS) were used in different parts by weight (1 wt.%, 5 wt.%, and 10 wt.%). The main aim of this modification—to enhance the thermal performance of the microencapsulated PCMs intended for textile applications. The morphologic analysis of the newly formed coating of MWCNTs or PEDOT: PSS microcapsules shell was observed by SEM. The heat storage and release capacity were evaluated by changing microcapsules MPCM32D shell modification. In order to evaluate the influence of the modified MF outer shell on the thermal properties of paraffin PCM, a thermal conductivity coefficient (λ) of these unmodified and shell-modified microcapsules was also measured by the comparative method. Based on the identified optimal parameters of the thermal performance of the tested PCM microcapsules, a 3D warp-knitted spacer fabric from PET was treated with a composition containing 5 wt.% MWCNTs or 5 wt.% PEDOT: PSS shell-modified microcapsules MPCM32D and acrylic resin binder. To assess the dynamic thermal behaviour of the treated fabric samples, an IR heating source and IR camera were used. The fabric with 5 wt.% MWCNTs or 5 wt.% PEDOT: PSS in shell-modified paraffin microcapsules MPCM32D revealed much faster heating and significantly slower cooling compared to the fabric treated with the unmodified ones. The thermal conductivity of the investigated fabric samples with modified microcapsules MPCM32D has been improved in comparison to the fabric samples with unmodified ones. That confirms the positive influence of using thermally conductive enhancing additives for the heat transfer rate within the textile sample containing these modified paraffin PCM microcapsules. Full article

(This article belongs to the Special Issue Function of Polymers in Encapsulation Process)

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14 pages, 1984 KiB

Open AccessArticle

Design of New Polyacrylate Microcapsules to Modify the Water-Soluble Active Substances Release

by Valentina Sabatini, Laura Pellicano, Hermes Farina, Eleonora Pargoletti, Luisa Annunziata, Marco A. Ortenzi, Alessandro Stori and Giuseppe Cappelletti

Polymers 2021, 13(5), 809; https://doi.org/10.3390/polym13050809 - 6 Mar 2021

Cited by 7 | Viewed by 3564

Abstract

Despite the poor photochemical stability of capsules walls, polyacrylate is one of the most successful polymers for microencapsulation. To improve polyacrylate performance, the combined use of different acrylate-based polymers could be exploited. Herein butyl methacrylate (BUMA)-based lattices were obtained via free radical polymerization in water by adding (i) methacrylic acid (MA)/methyl methacrylate (MMA) and (ii) methacrylamide (MAC) respectively, as an aqueous phase in Pickering emulsions, thanks to both the excellent polymer shells’ stability and the high encapsulation efficiency. A series of BUMA_MA_MMA terpolymers with complex macromolecular structures and BUMA_MAC linear copolymers were synthesized and used as dispersing media of an active material. Rate and yield of encapsulation, active substance adsorption onto the polymer wall, capsule morphology, shelf-life and controlled release were investigated. The effectiveness of the prepared BUMA-based microcapsules was demonstrated: BUMA-based terpolymers together with the modified ones (BUMA_MAC) led to slow (within ca. 60 h) and fast (in around 10 h) releasing microcapsules, respectively. Full article

(This article belongs to the Special Issue Function of Polymers in Encapsulation Process)

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14 pages, 8131 KiB

Open AccessArticle

Lignin-Stabilized Doxorubicin Microemulsions: Synthesis, Physical Characterization, and In Vitro Assessments

by Abbas Rahdar, Saman Sargazi, Mahmood Barani, Sheida Shahraki, Fakhara Sabir and M. Ali Aboudzadeh

Polymers 2021, 13(4), 641; https://doi.org/10.3390/polym13040641 - 21 Feb 2021

Cited by 34 | Viewed by 3041

Abstract

Encapsulation of the chemotherapy agents within colloidal systems usually improves drug efficiency and decreases its toxicity. In this study, lignin (LGN) (the second most abundant biopolymer next to cellulose on earth) was employed to prepare novel doxorubicin (DOX)-loaded oil-in-water (O/W) microemulsions with the aim of enhancing the bioavailability of DOX. The droplet size of DOX-loaded microemulsion was obtained as ≈ 7.5 nm by dynamic light scattering (DLS) analysis. The entrapment efficiency (EE) % of LGN/DOX microemulsions was calculated to be about 82%. In addition, a slow and sustainable release rate of DOX (68%) was observed after 24 h for these microemulsions. The cytotoxic effects of standard DOX and LGN/DOX microemulsions on non-malignant (HUVEC) and malignant (MCF7 and C152) cell lines were assessed by application of a tetrazolium (MTT) colorimetric assay. Disruption of cell membrane integrity was investigated by measuring intracellular lactate dehydrogenase (LDH) leakage. In vitro experiments showed that LGN/DOX microemulsions induced noticeable morphological alterations and a greater cell-killing effect than standard DOX. Moreover, LGN/DOX microemulsions significantly disrupted the membrane integrity of C152 cells. These results demonstrate that encapsulation and slow release of DOX improved the cytotoxic efficacy of this anthracycline agent against cancer cells but did not improve its safety towards normal human cells. Overall, this study provides a scientific basis for future studies on the encapsulation efficiency of microemulsions as a promising drug carrier for overcoming pharmacokinetic limitations. Full article

(This article belongs to the Special Issue Function of Polymers in Encapsulation Process)

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41 pages, 3935 KiB

Open AccessReview

Designing Natural Polymer-Based Capsules and Spheres for Biomedical Applications—A Review

by Kusha Sharma, Ze’ev Porat and Aharon Gedanken

Polymers 2021, 13(24), 4307; https://doi.org/10.3390/polym13244307 - 9 Dec 2021

Cited by 23 | Viewed by 5576

Abstract

Natural polymers, such as polysaccharides and polypeptides, are potential candidates to serve as carriers of biomedical cargo. Natural polymer-based carriers, having a core–shell structural configuration, offer ample scope for introducing multifunctional capabilities and enable the simultaneous encapsulation of cargo materials of different physical and chemical properties for their targeted delivery and sustained and stimuli-responsive release. On the other hand, carriers with a porous matrix structure offer larger surface area and lower density, in order to serve as potential platforms for cell culture and tissue regeneration. This review explores the designing of micro- and nano-metric core–shell capsules and porous spheres, based on various functions. Synthesis approaches, mechanisms of formation, general- and function-specific characteristics, challenges, and future perspectives are discussed. Recent advances in protein-based carriers with a porous matrix structure and different core–shell configurations are also presented in detail. Full article

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16 pages, 2731 KiB

Open AccessReview

Recent Developments in Ion-Sensitive Systems for Pharmaceutical Applications

by Michał Rudko, Tomasz Urbaniak and Witold Musiał

Polymers 2021, 13(10), 1641; https://doi.org/10.3390/polym13101641 - 18 May 2021

Cited by 22 | Viewed by 3128

Abstract

Stimuli-responsive carriers of pharmaceutical agents have been extensively researched in recent decades due to the possibility of distinctively precise targeted drug delivery. One of the potentially beneficial strategies is based on the response of the medical device to changes in the ionic environment. Fluctuations in ionic strength and ionic composition associated with pathological processes may provide triggers sufficient to induce an advantageous carrier response. This review is focused on recent developments and novel strategies in the design of ion-responsive drug delivery systems. A variety of structures i.e., polymeric matrices, lipid carriers, nucleoside constructs, and metal-organic frameworks, were included in the scope of the summary. Recently proposed strategies aim to induce different pharmaceutically beneficial effects: localized drug release in the desired manner, mucoadhesive properties, increased residence time, or diagnostic signal emission. The current state of development of ion-sensitive drug delivery systems enabled the marketing of some responsive topical formulations. Concurrently, ongoing research is focused on more selective and complex systems for different administration routes. The potential benefits in therapeutic efficacy and safety associated with the employment of multi-responsive systems will prospectively result in further research and applicable solutions. Full article

(This article belongs to the Special Issue Function of Polymers in Encapsulation Process)

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16 pages, 31875 KiB

Open AccessReview

Development of a New Polymeric Nanocarrier Dedicated to Controlled Clozapine Delivery at the Dopamine D₂-Serotonin 5-HT_1A Heteromers

by Sylwia Łukasiewicz

Polymers 2021, 13(7), 1000; https://doi.org/10.3390/polym13071000 - 24 Mar 2021

Cited by 4 | Viewed by 2646

Abstract

Clozapine, the second generation antipsychotic drug, is one of the prominent compounds used for treatment of schizophrenia. Unfortunately, use of this drug is still limited due to serious side effects connected to its unspecific and non-selective action. Nevertheless, clozapine still remains the first-choice drug for the situation of drug-resistance schizophrenia. Development of the new strategy of clozapine delivery into well-defined parts of the brain has been a great challenge for modern science. In the present paper we focus on the presentation of a new nanocarrier for clozapine and its use for targeted transport, enabling its interaction with the dopamine D₂ and serotonin 5-HT_1A heteromers (D₂-5-HT_1A) in the brain tissue. Clozapine polymeric nanocapsules (CLO-NCs) were prepared using anionic surfactant AOT (sodium docusate) as an emulsifier, and bio-compatible polyelectrolytes such as: poly-l-glutamic acid (PGA) and poly-l-lysine (PLL). Outer layer of the carrier was grafted by polyethylene glycol (PEG). Several variants of nanocarriers containing the antipsychotic varying in physicochemical parameters were tested. This kind of approach may enable the availability and safety of the drug, improve the selectivity of its action, and finally increase effectiveness of schizophrenia therapy. Moreover, the purpose of the manuscript is to cover a wide scope of the issues, which should be considered while designing a novel means for drug delivery. It is important to determine the interactions of a new nanocarrier with many cell components on various cellular levels in order to be sure that the new nanocarrier will be safe and won’t cause undesired effects for a patient. Full article

(This article belongs to the Special Issue Function of Polymers in Encapsulation Process)

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