Miniemulsion Polymerization Research Articles

Fabrication of efficient, magnetic graphene oxide nanocomposite for the enhanced photodegradation of organic dyes under visible light

This study reports magnetic graphene oxide composite microspheres (MGO) were firstly synthesized via one step miniemulsion polymerization. α-FeOOH rods were then loaded onto MGO via a facile hydrothermal method to prepare α-FeOOH@MGO, which was served as the photocatalyst for the Fenton reaction. Subsequently, the properties of the resulting α-FeOOH@MGO were characterized by FT-IR, XRD, SEM, VSM and UV-vis DRS analysis methods. The influence of various parameters was investigated, such as dye type, dye concentration, H2O2 dosage, catalysts dosage and pH of MO solution during heterogeneous photo-Fenton processes. Under visible light irradiation, the degradation rate of MO, MB and CR could reach 99.96%, 98.47% and 99.97% in 40 min, respectively. Six cycle experiments confirmed that the α-FeOOH@MGO possessed a satisfied stability and recycling ability. In addition, the photocatalytic reaction mechanism was also revealed by the Mott-Schottky plot, band structure and trapping experiments of active species.

Molecularly imprinted nanoparticles with recognition properties towards diphtheria toxin for ELISA applications

Plastic antibodies can be used for in vitro neutralization of biomacromolecules with different fragments due to their potential in separation, purification, chemical sensor, catalysis and drug production studies. These polymer nanoparticles with binding affinity and selectivity comparable to natural antibodies were prepared using functional monomer synthesis and copolymerization of acrylic monomers via miniemulsion polymerization. As a result, the in vitro cytotoxic effect from diphtheria toxin was reduced by MIPs. In vitro imaging experiments of polymer nanoparticles (plastic antibodies) were performed to examine the interaction of diphtheria toxin with actin filaments, and MIPs inhibited diphtheria toxin damage on actin filaments. The enzyme-linked immunosorbent assay (ELISA) was performed with plastic antibodies labeled with biotin, and it was determined that plastic antibodies could also be used for diagnostic purposes. We report that molecularly imprinted polymers (MIPs), which are biocompatible polymer nanoparticles, can capture and reduce the effect of diphtheria toxic and its fragment A.

Photoluminescent Polymer Nanoparticles Based on Oxazolidine Derivatives for Authentication and Security Marking of Confidential Notes.

Colloidal materials have widely been used to develop innovative anticounterfeiting nanoinks for information encryption. Latex nanoparticles based on methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (HEMA) bearing hydroxyl functional groups were synthesized via semicontinuous miniemulsion polymerization. The size determination of the nanoparticles and microscopic results showed mostly spherical nanoparticles with a narrow size distribution and a mean size of about 80 nm. Two oxazolidine derivatives were physically doped at the surface of the nanoparticles to prepare photoluminescent polymer nanoparticles. Hydroxyl functional groups at the surface of the nanoparticles led to their hydrogen bonding interactions with the doped luminescent compounds. Optical analysis of the photoluminescent nanoparticles displayed different fluorescence emission and UV-vis absorbance intensities based on the amount of polar groups located at the surface of colloidal nanoparticles. Reducing the particle size to below 100 nm along with increasing the surface area can assist the decrease of the light reflectance and improvement of the latex nanoparticles' efficiency in the anticounterfeiting industry. This preparation methodology can efficiently provide remarkable photoreversible anticounterfeiting nanoinks used in different applications, such as print marking, security encoded tags, labeling, probing, and handwriting.

Novel serotonin decorated molecularly imprinted polymer nanoparticles based on biodegradable materials; A potential self-targeted delivery system for Irinotecan

Non-covalent imprinting polymerization was adopted to fabricate a novel molecularly imprinted polymer (MIP) for the targeted delivery of Irinotecan. The optimized condition to obtain a MIP with the highest binding efficiency was investigated by using different proportions of monomer to cross-linker. To overcome the drawbacks of conventional drug delivery systems, two main strategies in the preparation of the carrier were applied. Metformin as a non-hazardous material, with potential anti-cancer and targeted delivery properties, was used to fabricate the monomer. Moreover, the surface of the carrier was modified by serotonin (5-hydroxytryptamine). To improve the cellular uptake, prolong the circulation time, and to provide an appropriate accumulation of the drug at the tumor site, uniform, and nanoparticles were fabricated via mini-emulsion polymerization route. The structure of the prepared monomer was characterized using FTIR, 1HNMR, 13CNMR, and mass spectroscopy. The adsorption isotherm of the Irinotecan-MIP nanoparticles was investigated. Bio-distribution assay results revealed a suitable distribution of carrier nanoparticles in mice bodies. A controlled release profile with a maximum release of 83% in more acidic condition, was achieved for the designed formulation. According to all the above functions, it is believed that this study suggests a novel nano-carrier for the targeted delivery of Irinotecan.

Molecularly Imprinted Ligand-Free Nanogels for Recognizing Bee Venom-Originated Phospholipase A2 Enzyme.

In this study, ligand-free nanogels (LFNGs) as potential antivenom mimics were developed with the aim of preventing hypersensitivity and other side effects following massive bee attacks. For this purpose, poly (ethylene glycol) diacrylate was chosen as a main synthetic biocompatible matrix to prepare the experimental LFNGs. The overall concept uses inverse mini-emulsion polymerization as the main route to deliver nanogel caps with complementary cavities for phospholipase A2 (PLA2) from bee venom, created artificially with the use of molecular imprinting (MI) technologies. The morphology and the hydrodynamic features of the nanogels were confirmed by transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis. The following rebinding experiments evidenced the specificity of molecularly imprinted LFNG for PLA2, with rebinding capacities up to 8-fold higher compared to the reference non-imprinted nanogel, while the in vitro binding assays of PLA2 from commercial bee venom indicated that such synthetic nanogels are able to recognize and retain the targeted PLA2 enzyme. The results were finally collaborated with in vitro cell-viability experiments and resulted in a strong belief that such LFNG may actually be used for future therapies against bee envenomation.

Electroconductive PEDOT nanoparticle integrated scaffolds for spinal cord tissue repair

BackgroundHostile environment around the lesion site following spinal cord injury (SCI) prevents the re-establishment of neuronal tracks, thus significantly limiting the regenerative capability. Electroconductive scaffolds are emerging as a promising option for SCI repair, though currently available conductive polymers such as polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) present poor biofunctionality and biocompatibility, thus limiting their effective use in SCI tissue engineering (TE) treatment strategies.MethodsPEDOT NPs were synthesized via chemical oxidation polymerization in miniemulsion. The conductive PEDOT NPs were incorporated with gelatin and hyaluronic acid (HA) to create gel:HA:PEDOT-NPs scaffolds. Morphological analysis of both PEDOT NPs and scaffolds was conducted via SEM. Further characterisation included dielectric constant and permittivity variances mapped against morphological changes after crosslinking, Young’s modulus, FTIR, DLS, swelling studies, rheology, in-vitro, and in-vivo biocompatibility studies were also conducted.ResultsIncorporation of PEDOT NPs increased the conductivity of scaffolds to 8.3 × 10–4 ± 8.1 × 10–5 S/cm. The compressive modulus of the scaffold was tailored to match the native spinal cord at 1.2 ± 0.2 MPa, along with controlled porosity. Rheological studies of the hydrogel showed excellent 3D shear-thinning printing capabilities and shape fidelity post-printing. In-vitro studies showed the scaffolds are cytocompatible and an in-vivo assessment in a rat SCI lesion model shows glial fibrillary acidic protein (GFAP) upregulation not directly in contact with the lesion/implantation site, with diminished astrocyte reactivity. Decreased levels of macrophage and microglia reactivity at the implant site is also observed. This positively influences the re-establishment of signals and initiation of healing mechanisms. Observation of axon migration towards the scaffold can be attributed to immunomodulatory properties of HA in the scaffold caused by a controlled inflammatory response. HA limits astrocyte activation through its CD44 receptors and therefore limits scar formation. This allows for a superior axonal migration and growth towards the targeted implantation site through the provision of a stimulating microenvironment for regeneration.ConclusionsBased on these results, the incorporation of PEDOT NPs into Gel:HA biomaterial scaffolds enhances not only the conductive capabilities of the material, but also the provision of a healing environment around lesions in SCI. Hence, gel:HA:PEDOT-NPs scaffolds are a promising TE option for stimulating regeneration for SCI.

Novel biodegradable molecularly imprinted polymer nanoparticles for drug delivery of methotrexate anti-cancer; synthesis, characterization and cellular studies.

Recently biodegradable nanoparticles are the center of attention for the development of drug delivery systems. Molecularly imprinted polymer (MIP) is an interesting candidate for designing drug nano-carriers. MIP-based nanoparticles could be used for cancer treatment and exhibited the potential to fill gaps regarding to ligand-based nanomaterials. Also, the presence of a cross-linker can play an essential role in nanoparticle stability and physicochemical properties of nanoparticles after synthesis. In this research, a biodegradable drug delivery system based on MIP nanoparticles was prepared using a biodegradable cross-linker (dimethacryloyl hydroxylamine, DMHA) for methotrexate (MTX). A hydrolysable functional group CO-O-NH-CO was added to the crosslinking agent to increase the final biodegradability of the polymer. Firstly, a biodegradable cross-linker was synthesized. Then, the non-imprinted polymers were prepared through mini-emulsion polymerization in the absence of a template; and efficient particle size distribution was determined. Finally, methotrexate was placed in imprinted polymers to achieve the desired MIP. Different types of MIPs were synthesized using different molar ratios of template, cross-linker, and functional monomer, and the optimal molar ratio was obtained at 1:4:20, respectively. HNMR successfully confirmed the chemical structure of the cross-linker. According to SEM images, nanoparticles had a spherical shape with a smooth surface. The imprinted nanoparticles showed a narrow size distribution with an average of 120nm at a high ratio of cross-linker. The drug loading and entrapment efficiency were 6.4% and 92%, respectively. The biodegradability studies indicated that the nanoparticles prepared by DMHA had a more degradability rate than ethylene glycol dimethacrylate as a conventional cross-linker. Also, the polymer degradation rate was higher in alkaline environments. Release studies in physiological and alkaline buffer showed an initial burst release of a quarter of loaded MTX during the day and a 70% release during a week. The Korsmeyer-Peppas model described the release pattern. The cytotoxicity of MTX loaded in nanoparticles was studied on the MCF-7 cell line, and the IC50 was 3.54μg/ml. It was demonstrated that nanoparticles prepared by DMHA have the potential to be used as biodegradable drug carriers for anticancer delivery. Synthesis schema of molecular imprinting of methotrexate in biodegradable polymer based on dimethacryloyl hydroxylamine cross-linker, for use as nanocarrier anticancer delivery to breast tumor.

Trithiocarbonate-Mediated RAFT Polymerization Enables the Synthesis of Homotelechelic N-Vinylpyrrolidone Oligomers with Surfactant Properties

Poly(N-vinylpyrrolidone) (PVP) is a well-known biocompatible polymer widely used in cosmetics, pharmaceuticals, and many other applications and is usually synthesized via radical polymerization. High molar mass PVP lacks biodegradability according to the OECD 301 F standard and can lead to permanent accumulation within the body or in the environment. Nowadays, lower molar mass PVP is produced via xanthate-mediated reversible addition–fragmentation chain-transfer (RAFT) polymerization. However, this type of polymerization also leads to a large amount of undesired dimer formation. Herein, various homotelechelic PVP oligomers were prepared via a trithiocarbonate-mediated RAFT polymerization with the production of a minimal amount of unsaturated dimer. These PVP oligomers showed similar surfactant properties as the well-known Lutensol AT50 surfactant, and they were used as a nonionic surfactant in a typical radical aqueous miniemulsion polymerization of methyl methacrylate (MMA) to produce well-defined PMMA nanoparticles. Additionally, PVP oligomers showed no toxicity to the bacterial strain Escherichia coli and to the water fleas Daphnia pulex, which is promising for safe release in wastewater systems.

Advanced Fabrication of miRNA-Based Electrochemical Nanobiosensor for Diagnosis of Breast Cancer

Early diagnosis is the key to easy, low cost, and effective treatment of breast cancer. Therefore, studies have been accelerated to identify breast cancer diagnostic biomarkers and diagnose cancer before it progresses. The use of miR-155 as a potential biomarker in breast cancer, which has different levels at different stages of the disease, provides a simple serological test for breast cancer prognosis/diagnosis, follow-up, and treatment. Nanopolymers containing different functional groups that are formed by thiol affinity technique were synthesized by mini emulsion polymerization method and advanced characterization studies were carried out in this study to be used as bioactive layers in the nanobiosensor system for miRNA detection. The working conditions of the electrochemical nanobiosensor in which nanopolymers are used as bioactive layers were optimized. Analytical measurement characteristics and validation studies of the nanobiosensor were determined and analysis was performed on commercial blood serum. The potential of the developed electrochemical biosensor to be used as a medical diagnostic kit was explained by comparing it with commercial miRNA kit currently used for the detection of miR-155. This novel nanobiosensor provide sensitive, reliable, and rapid detection of miR-155 and it can provide the potential for breast cancer early diagnosis, prognosis, and follow-up.

Delicate and Independent Manipulation of Dynamic Fluorescence Behavior of Polymer Nanoparticles Based on a Core-Shell Strategy.

Fluorescent polymer nanomaterials with dynamic fluorescence properties hold great potential in many advanced applications, including but not limited to information encryption, adaptive camouflage, and biosensors. The key to improving the application value of materials is to establish an accurate control strategy for dynamic fluorescence behavior. Herein, we develop a core-shell engineering strategy to precisely and independently manipulate the dynamic fluorescence behavior through the shell polymeric matrix. The core-shell fluorescent polymer nanoparticles (CS-FPNPs) are constructed through a sequential process of miniemulsion polymerization and seeded emulsion polymerization. Taking advantage of the core-shell structure, the rigid core matrix ensures the strong initial emission of AIE units, while the photoisomerization behavior of spiropyrane (SP) units is delicately and independently regulated by the rigidness of the shell matrix. Thereby, CS-FPNPs exhibit bright time-dependent reversible dynamic fluorescence behavior under alternating UV/vis irradiation. Benefited from the excellent processability and film formation ability, we have successfully applied CS-FPNPs to dynamic decorative painting, warning labels, and dynamic QR code security. Impressively, the fluorescence manipulation strategy based on core-shell engineering allows the independent regulation of specific luminescent units in complicated emission systems to accurately embody designed emission behavior.

Synthesis of electrically conducting nanocomposites via Pickering miniemulsion polymerization: Effect of graphene oxide functionalized with different capping agents

Modification of graphene oxide (GO) sheets with various capping agents has been explored within the context of miniemulsion polymerization as a synthetic route towards ambient temperature film forming latexes for fabrication of electrically conducting films after thermal reduction to generate reduced GO. Miniemulsion polymerizations of styrene/n-butyl acrylate were conducted in the presence of non-modified GO as well as GO functionalized with poly(methyl methacrylate) (GO-PMMA), poly(di(ethylene glycol) ethyl ether acrylate) (GO-PDEGA), and carboxylic acid groups (GO-COOH). Colloidal instability was encountered for GO-PMMA and GO-PDEGA, but stable latexes and nanocomposite films were successfully obtained using GO and GO-COOH. Electrical conductivities in the approximate range of 0.1–4 S m−1 were obtained, with GO-COOH giving slightly lower values than GO, and the presence of sodium dodecyl sulfate (SDS) resulting in increasing conductivity values for both GO and GO-COOH.

Innovative bifunctional heat storage nanocapsules containing polymerizable surfactant for antimicrobial thermoregulating clothes

Bifunctional poly(methyl methacrylate)/Rubitherms®27 (PMMA/RT27) nanocapsules were fabricated by miniemulsion polymerization using poly(2-methacryloyloxy dodecyl dimethyl ammonium chloride-4-allyloxy-2-hydroxy benzophenone)-block-polymethyl methacrylate-iodide (P(QAC12-BP)-b-PMMA-I) as a polymerizable surfactant. Approximately 50-nm spherical core-shell nanocapsules were formed with a highly positive surface charge (≥ +70 mV) derived from the quaternary ammonium (QA) groups in QAC12 units. The QA groups distributed on the nanocapsules’ surfaces effectively presented cationic characteristics and antimicrobial performance. High RT27 loading and encapsulation efficiency PMMA nanocapsules were produced using an MMA: RT27 ratio of 50: 50 with high latent heats of the encapsulated RT27, close to those of the pristine ones. Because of the existence of the BP unit in the polymerizable surfactant located on nanocapsules’ surfaces, the obtained nanocapsules were strongly coated on cotton fabrics by irradiation with UV light, giving them greater washing durability than using an external binder. The coated fabrics exhibited effective antimicrobial performance against S. epidermidis and C. glutamigum. Therefore, the fabricated PMMA/RT27 nanocapsules presenting thermoregulating and antimicrobial properties are well suited for application on textiles.

Monitoring the Formation of Polymer Nanoparticles with Fluorescent Molecular Rotors

We present an experimental approach to studying the kinetics of polymer nanoparticle formation using molecular rotor molecules as fluorescence probes. By combining fluorescence lifetime analysis and fluorescence correlation spectroscopy, it is possible to simultaneously monitor the evolution of the local environment in the nanoparticles and their size. To assess the generality of the method, we select two common but very different methods for nanoparticle preparation: emulsion-solvent evaporation and miniemulsion polymerization. In both cases, three stages of the nanoparticle formation process were identified on the basis of their polymer content. In the initial stage of the process, the polymer content is low. Then it increases rapidly because of solvent evaporation or polymerization during the second stage. Finally, it reaches a plateau value. Furthermore, significant heterogeneities in the final nanoparticles were found that can be attributed to remaining solvent or monomer and the spatial variation of the polymer-free volume.

Stabilization of Aqueous MMA Emulsions Using Mixtures of Surfactants and Implications on MMA Miniemulsion Polymerizations

AbstractMiniemulsion polymerization is a robust and simple method for manufacture of polymer nanoparticles. However, it is strongly dependent on the precursor monomer‐in‐water emulsion stability. Thus, the present study investigates the influence of concentration and combination of nonionic surfactants (resulting in different hydrophile–lipophile balances, HLB) on the stabilization of emulsions of methyl methacrylate in water. Backscattering profiles obtained with Turbiscan show that a combination of Tween80 and Span80 can grant the desired initial system stabilization, although the optimum HLB values depend on the amount of surfactant mixture. Miniemulsion polymerizations are then successfully performed with nonionic surfactant mixtures, providing high monomer conversion in less than 1 h and poly(methyl methacrylate) nanoparticles with average diameters ranging from 300 to 500 nm. Finally, it is observed that the addition of small amounts of an anionic surfactant to the surfactant mixture (10 wt.%) can be very beneficial for the process, allowing the control of reaction rates, the production of smaller nanoparticles with average diameters from 100 to 300 nm, and the enhanced stabilization of the final solid dispersion, while simultaneously keeping the concentration of ionic surfactants small.

Long‐Term Synergistic Antibacterial Composite Films Boosted by Controlled Underwater Surface Reconstruction

AbstractImplanting bactericidal ability to low surface energy fluoropolymer is expected to develop advanced surfaces with excellent antibacterial performance for various applications. However, the fundamental conflicts, the difficulty of discharging release‐active bactericides from hydrophobic fluoropolymers and the trade‐off between the electrostatic contact‐active microbicides and the minimized surface interaction for contaminant release, are general consensus in the field and explain the very limited success in existing reports. The current work highlights an effective and feasible strategy that utilizes the interaction between silver nanoparticles (Ag NPs) and polymer matrices to generate composite films with controllable underwater surface reconstruction, enabling to regulate surface energy exquisitely to area facilitating the bacterial release and establish a synergistic bacteria‐killing action, and thereby boosting the bacteria‐killing and bacteria‐release simultaneously. Quaternized fluoropolymer/Ag NPs nanocomposite particles (qf‐polymer/Ag NCPs) are first synthesized through miniemulsion polymerization, and then used as building blocks to fabricate the quaternized fluoropolymer/Ag NPs nanocomposite films (qf‐polymer/Ag CFs) through a convenient squeegeeing technique. The qf‐polymer/Ag CFs display long‐term antibacterial performance against diverse bacteria. A synergistic antibacterial mechanism contributed by the Ag NPs, quaternary ammonium, and fluorinated components is proposed. This work provides new insight into the design, fabrication, and performance optimization of long‐term antibacterial surfaces for diverse applications.

Facile Fabrication of Hollow Molecularly Imprinted Polymer Particles with Multicore Structure via Miniemulsion Polymerization

Facile Fabrication of Hollow Molecularly Imprinted Polymer Particles with Multicore Structure via Miniemulsion Polymerization

Identification of novel cyanoacrylate monomers for use in nanoparticle drug delivery systems prepared by miniemulsion polymerisation – A multistep screening approach

Poly (alkyl cyanoacrylate) (PACA) polymeric nanoparticles (NPs) are promising drug carriers in drug delivery. However, the selection of commercially available alkyl cyanoacrylate (ACA) monomers is limited, because most monomers were designed for use in medical and industrial glues and later repurposed for drug encapsulation. This study therefore aimed to seek out novel ACA materials for use in NP systems using a toxicity led screening approach. A multistep strategy, including cytotoxicity screening of alcohols as degradation products of PACA (44 alcohols), NPs (14 polymers), and a final in vivo study (2 polymers) gave poly (2-ethylhexyl cyanoacrylate) PEHCA as a promising novel PACA candidate. For the first time, this work presents cytotoxicity data on several novel ACAs, PEHCA in vivo toxicity data, and miniemulsion polymerisation-based encapsulation of the cabazitaxel and NR688 in novel PACA candidates. Furthermore, several of the ACA candidates were compatible with a wider selection of lipophilic active pharmaceutical ingredients (APIs) versus commercially available controls. Combined, this work demonstrates the potential benefits of expanding the array of available ACA materials in drug delivery. Novel ACAs have the potential to encapsulate a wider range of APIs in miniemulsion polymerisation processes and may also broaden PACA applicability in other fields.

In Support of Commercial Applications of Miniemulsion Polymerization

In Support of Commercial Applications of Miniemulsion Polymerization

Photo-pH dual stimuli-responsive multicolor fluorescent polymeric nanoparticles for multicolor security ink, optical data encryption and zebrafish imaging

Stimuli-responsive fluorescent polymeric nanoparticles are widely used in bioimaging, anti-counterfeiting and data encryption due to their advantages of simple preparation, good water-dispersibility, high brightness and photostability. In this paper, novel photo-pH dual stimuli-responsive multicolor fluorescent polymeric nanoparticles (SMFPNs) were fabricated via combination of one-pot miniemulsion polymerization and surface modification. Based on fluorescence resonance energy transfer (FRET) principle, 4-ethoxy-9-allyl-1,8-naphthalimide (EANI), fluorescein isothiocyanate (FITC) and spiropyran-linked methacrylate (SPMA) can be used to constitute three pairs of FRET systems. In the nanoparticles, the blue fluorescence of EANI (energy donor) decreases and the green fluorescence of FITC (energy receptor) increases via increasing pH. While pH decreases, it can return to blue fluorescence. Meanwhile, after UV light irradiation, SPMA converts from non-fluorescent spiropyrans (SP) state to red fluorescent merocyanine (MC) state, the transformation from blue or green emission to red emission can be realized. When irradiated with visible light, it reverts to its original blue or green fluorescence. Therefore, the system can achieve the multi-color transformation of blue, green and red under changing pH and illumination conditions. In addition, the as-prepared nanoparticles also exhibited high fluorescence contrast, rapid photo-responsiveness and excellent photoreversibility. Therefore, SMFPNs displayed great potential in the fields of multicolor security ink, advanced anti-counterfeiting, multilevel data encryption and in vivo bioimaging.

Controlling size, shape, and charge of nanoparticles via low-energy miniemulsion and heterogeneous RAFT polymerization

Size, shape, and charge are key parameters of nanoparticles, and variations in these parameters can significantly impact their properties and applications. Among various nanoparticle synthesis methods, the combination of low-energy miniemulsions with reversible addition-fragmentation chain-transfer (RAFT) polymerization allows for the facile, rapid, and environmentally friendly preparation of uniform nanoparticles. However, this method cannot, yet, simultaneously control the size, shape, and charge of nanoparticles, thereby limiting its potential applications. Here we report the synthesis of polymeric nanoparticles with concurrent control over particle size, shape, and charge via low-energy miniemulsion and heterogeneous RAFT polymerization. Key to our approach is the combination of (i) a macromolecular surface-active agent to facilitate the formation of nanodroplets, (ii) various small-molecule surfactants with different charges to control the size and charge of nanodroplets, and (iii) a molecular transformer to control the morphology of the final polymeric nanoparticles. In particular, negatively charged polystyrene nanoparticles of different sizes (from ∼100 to ∼500 nm) and shapes (sphere, worm, and vesicle) were obtained by simply tuning the amount of added sodium dodecyl sulfate (SDS) and toluene. The nanoparticle charge was then switched from negative to positive by replacing SDS with cetyltrimethylammonium bromide (CTAB), a positively charged surfactant. In addition, biocompatible and neutral surfactants (including Tweens and Span 80) were employed to tune the nanoparticle size yielding challenging-to-synthesize nanoworms. This work provides a simple but powerful approach to produce nanoparticles of different properties, thus expanding the scope of nanomaterials made by RAFT low-energy miniemulsion polymerization.