Molecular interactions, internal structure and drug release kinetics of rationally developed polymer–lipid hybrid nanoparticles

On the formation and stability mechanisms of diverse lipid-based nanostructures for drug delivery

In the evolving landscape of nanotechnology and pharmaceuticals, lipid nanostructures have emerged as pivotal areas of research due to their unique ability to mimic biological membranes and encapsulate active molecules. These nanostructures offer promising avenues for drug delivery, vaccine development, and diagnostic applications. This comprehensive review explores the complex mechanisms underlying the formation and stability of various lipid nanostructures, including lipid liquid crystalline nanoparticles and solid lipid nanoparticles. Drawing upon a wide array of studies, we integrate current knowledge on the physicochemical properties of lipids that contribute to nanostructure formation, such as lipid composition, charge, and the role of environmental factors such as pH and ionic strength. We further discuss the stabilisation mechanisms that preserve the integrity and functionality of these nanostructures in biological systems, highlighting the influence of surface modification, PEGylation, and the incorporation of stabilising agents. Through a methodical examination of both classical theories and cutting-edge research, our review highlights the critical factors that dictate the self-assembly of lipids into nanostructures, the dynamics of their formation, and the interplay between different stabilising forces. The implications of these insights for the design of lipid-based delivery systems are vast, offering the potential to enhance the bioavailability of therapeutics, target specific tissues or cells, and minimise adverse effects. The integration of lipid nanostructures in pharmaceutical nanotechnology not only stands to revolutionise the delivery of therapeutic agents but also paves the way for innovative applications in targeted therapy, personalised medicine, and vaccine adjuvant development. By bridging the gap between fundamental biophysical studies and applied research, this review contributes to the ongoing discourse on lipid nanostructures, advocating for a multidisciplinary approach to harness their full potential.

Erucin-loaded chitosan coated solid lipid hybrid nanoparticles: An efficient drug delivery system for enhancing solubility and sustained release

This study investigates enhancing the solubility, bioavailability, and sustained release of erucin, a lipophilic compound from Eruca sativa seeds, using chitosan-coated lipid polymer hybrid nanoparticles (ER-LPHNPs). Optimized ER-LPHNPs were evaluated for in vitro and in vivo properties. The developed formulation was characterized using various techniques and studied for its toxicity on RAW 246.7 cell line and baker's yeast along with glucose uptake assay on baker's yeast and L6 cell line. ER-LPHNPs (size: 112.3667 ± 1.76 nm, PDI: 0.244 ± 0.012, ZP: +33.6 mV) showed spherical morphology by HR-TEM, FE-SEM, AFM and encapsulation efficiency exceeded 90 %, with sustained release at pH 7.4. FTIR confirmed the encapsulation of erucin and absence of drug-excipients covalent interactions. ER-LPHNPs and erucin were non-toxic to baker's yeast at concentrations up to 3000 μg/mL, with ER-LPHNPs enhancing glucose uptake over erucin and metronidazole. ER-LPHNPs also showed reduced toxicity on Raw 246.7 cells and significantly improved glucose uptake in L6 cell line. In vivo pharmacokinetics study demonstrated ER-LPHNPs increased drug's bioavailability by 256 %. Additionally, ER-LPHNPs enhanced the Cmax and Tmax of Erucin, which validates the sustained release of drug from the nanoparticles as compared to ER-CMC suspension. Thus, ER-LPHNPs act as a controlled nano-delivery system by addressing solubility, bioavailability, and sustained release challenges.

Core-Shell Nanoparticles for Pulmonary Drug Delivery

Nanoscale drug delivery systems have provoked interest for application in various therapies on account of their ability to elevate the intracellular concentration of drugs inside target cells, which leads to an increase in efficacy, a decrease in dose, and dose-associated adverse effects. There are several types of nanoparticles available; however, core-shell nanoparticles outperform bare nanoparticles in terms of their reduced cytotoxicity, high dispersibility and biocompatibility, and improved conjugation with drugs and biomolecules because of better surface characteristics. These nanoparticulate drug delivery systems are used for targeting a number of organs, such as the colon, brain, lung, etc. Pulmonary administration of medicines is a more appealing method as it is a noninvasive route for systemic and locally acting drugs as the pulmonary region has a wide surface area, delicate blood-alveolar barrier, and significant vascularization. A core-shell nano-particulate drug delivery system is more effective in the treatment of various pulmonary disorders. Thus, this review has discussed the potential of several types of core-shell nanoparticles in treating various diseases and synthesis methods of core-shell nanoparticles. The methods for synthesis of core-shell nanoparticles include solid phase reaction, liquid phase reaction, gas phase reaction, mechanical mixing, microwave- assisted synthesis, sono-synthesis, and non-thermal plasma technology. The basic types of core-shell nanoparticles are metallic, magnetic, polymeric, silica, upconversion, and carbon nanomaterial- based core-shell nanoparticles. With this special platform, it is possible to integrate the benefits of both core and shell materials, such as strong serum stability, effective drug loading, adjustable particle size, and immunocompatibility.

From Burst to Sustained Release: The Effect of Antibiotic Structure Incorporated into Chitosan-Based Films

Background/Objectives: Medical devices are susceptible to bacterial colonization and biofilm formation, which can result in severe infections, leading to prolonged hospital stays and increased burden on society. Antibacterial films have the potential to assist in preventing biofilm formation, thereby reducing administration of antibiotics and the emergence of antibiotic-resistant strains. In a previous study, a chitosan-based matrix crosslinked with tannic acid and loaded with gentamicin was reported. In this study, five different antibiotics (moxifloxacin, ciprofloxacin, trimethoprim, sulfamethoxazole or linezolid) were loaded into these chitosan-based films, and their impact on the release behavior carefully assessed. Methods: The samples were characterized according to their thickness, swelling, and mass loss in phosphate-buffered saline (PBS), as well as by morphology using scanning electron microscopy (SEM) and optical phase contrast microscopy. Antibiotic release over time was quantified in PBS by high-performance liquid chromatography (HPLC). Antibacterial activity was investigated by disk diffusion test and antibiotic release over time. Finally, the cytotoxicity of the samples was assessed with human dermal fibroblasts. Results: The obtained results differed significantly, especially regarding the antibiotic release time and antibacterial activity, which varied from one day to six months, enabling classification of the films from burst/transient to prolonged release. The films also showed antibacterial features against bacteria mostly present in medical devices and displayed to be non-cytotoxic. Conclusions: In conclusion, it was demonstrated that the antibiotics structure significantly alters the release kinetics, and that by carefully selecting the antibiotic, the consequent release can be tuned. This approach yielded films that could be used for potentially-scalable release in antimicrobial coatings specific to medical devices, aiming to reduce biomaterial associated infections (BAIs).

Inhaled Ivermectin-Loaded Lipid Polymer Hybrid Nanoparticles: Development and Characterization

Ivermectin (IVM), a drug originally used for treating parasitic infections, is being explored for its potential applications in cancer therapy. Despite the promising anti-cancer effects of IVM, its low water solubility limits its bioavailability and, consequently, its biological efficacy as an oral formulation. To overcome this challenge, our research focused on developing IVM-loaded lipid polymer hybrid nanoparticles (LPHNPs) designed for potential pulmonary administration. IVM-loaded LPHNPs were developed using the emulsion solvent evaporation method and characterized in terms of particle size, morphology, entrapment efficiency, and release pattern. Solid phase characterization was investigated by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Using a Twin stage impinger (TSI) attached to a device, aerosolization properties of the developed LPHNPs were studied at a flow rate of 60 L/min, and IVM was determined by a validated HPLC method. IVM-loaded LPHNPs demonstrated spherical-shaped particles between 302 and 350 nm. Developed formulations showed an entrapment efficiency between 68 and 80% and a sustained 50 to 60% IVM release pattern within 96 h. Carr's index (CI), Hausner ratio (HR), and angle of repose (θ) indicated proper flowability of the fabricated LPHNPs. The in vitro aerosolization analysis revealed fine particle fractions (FPFs) ranging from 18.53% to 24.77%. This in vitro study demonstrates the potential of IVM-loaded LPHNPs as a delivery vehicle through the pulmonary route.

An update on strategies for optimizing polymer-lipid hybrid nanoparticle-mediated drug delivery: exploiting transformability and bioactivity of PLN and harnessing intracellular lipid transport mechanism

INTRODUCTION

Polymer-lipid hybrid nanoparticle (PLN) is an emerging nanoplatform with distinct properties and functionalities from other nanocarrier systems. PLN can be optimized to overcome various levels of drug delivery barriers to achieve desired therapeutic outcomes via rational selection of polymer and lipid combinations based on a thorough understanding of their properties and interactions with therapeutic agents and biological systems.

AREAS COVERED

This review provides an overview of PLN including the motive and history of PLN development, types of PLN, preparation methods, attestations of their versatility, and design strategies to circumvent various barriers for increasing drug delivery accuracy and efficiency. It also highlights recent advances in PLN design including: rationale selection of polymer and lipid components to achieve spatiotemporal drug targeting and multi-targeted cascade drug delivery; utilizing the intracellular lipid transport mechanism for active targeting to desired organelles; and harnessing bioreactive lipids and polymers to magnify therapeutic effects.

EXPERT OPINION

A thorough understanding of properties of PLN components and their biofate is important for enhancing disease site targeting, deep tumor tissue penetration, cellular uptake, and intracellular trafficking of PLN. For futuristic PLN development, active lipid transport and dual functions of lipids and polymers as both nanocarrier material and pharmacological agents can be further explored.

Sonophoresis-assisted transdermal delivery of antimigraine-loaded nanolipomers: Radio-tracking, histopathological assessment and in-vivo biodistribution study

Migraine is a disabling neurovascular polygenic disorder affecting life quality with escorted socioeconomic encumbrances. Herein, we investigated the consolidated amalgamation of passive lipomer approach alongside active sonophoresis assisted transdermal delivery of zolmitriptan (ZT) using high frequency ultrasound pre-treatment protocol to mitigate migraine attacks. A modified nanoprecipitation technique was utilized to prepare zolmitriptan loaded lipomers (ZTL) adopting 23 factorial design. Three factors were scrutinized namely lipid type, ZT: lipid ratio and ZT: Gantrez® ratio. The prepared systems were characterized regarding particle size, zeta potential, polydispersity index, entrapment efficiency and in-vitro release studies. The best achieved ZTL system was evaluated for ZT- Gantrez® intermolecular interactions, drug crystallinity, morphology, ex-vivo permeation and histopathological examination. Finally, a comparative in-vivo biodistribution study through radiotracking technique using Technetium-99 m was adopted. L2 was the best-achieved ZTL system with respect to spherical particle size (390.7 nm), zeta-potential (-30.8 mV), PDI (0.2), entrapment efficiency (86.2%), controlled release profile, flux (147.13 μg/cm2/hr) and enhancement ratio (5.67). Histopathological studies proved the safety of L2 system upon application on skin. L2 revealed higher brain Cmax (12.21 %ID/g), prolonged brain MRT (8.67 hr), prolonged brain 0.23 hr), significantly high relative bioavailability (2929.36%) and similar brain Tmax (0.5 hr) compared to I.V. route with higher brain/blood ratio. Thus, sonophoresis assisted transdermal delivery of ZTL offers a propitious alterative to alleviate migraine symptoms.

Design and Optimization of a Nanoparticulate Pore Former as a Multifunctional Coating Excipient for pH Transition-Independent Controlled Release of Weakly Basic Drugs for Oral Drug Delivery

Bioavailability of weakly basic drugs may be disrupted by dramatic pH changes or unexpected pH alterations in the gastrointestinal tract. Conventional organic acids or enteric coating polymers cannot address this problem adequately because they leach out or dissolve prematurely, especially during controlled release applications. Thus, a non-leachable, multifunctional terpolymer nanoparticle (TPN) made of cross-linked poly(methacrylic acid) (PMAA)-polysorbate 80-grafted-starch (PMAA-PS 80-g-St) was proposed to provide pH transition-independent release of a weakly basic drug, verapamil HCl (VER), by a rationally designed bilayer-coated controlled release bead formulation. The pH-responsive PMAA and cross-linker content in the TPN was first optimized to achieve the largest possible increase in medium uptake alongside the smallest decrease in drug release rate at pH 6.8, relative to pH 1.2. Such TPNs maintained an acidic microenvironmental pH (pH_m) when loaded in ethylcellulose (EC) films, as measured using pH-indicating dyes. Further studies of formulations revealed that with the 1:2 VER:TPN ratio and 19% coating weight gain, bilayer-coated beads maintained a constant release rate over the pH transition and exhibited extended release up to 18 h. These results demonstrated that the multifunctional TPN as a pH_m modifier and pH-dependent pore former could overcome the severe pH-dependent solubility of weakly basic drugs.

Assembly methods for asymmetric lipid and polymer-lipid vesicles

Asymmetric unilamellar vesicles are aqueous bodies surrounded by two dissimilar leaflets made from lipids, polymers, or both. They are great models for cell membranes and attractive vehicles in potential biomedicine applications. Despite their promise, asymmetric unilamellar vesicles are not widely studied or adopted in applications. This is largely due to the complexity in generating asymmetric membranes. Recent technical advances in microfluidics have opened doors to high throughput fabrication of asymmetric unilamellar vesicles. In this review, we focus on microfluidic methods for generating asymmetric lipid vesicles, with two dissimilar lipid leaflets, and asymmetric lipid-polymer vesicles, with one lipid leaflet and one polymer leaflet. We also review a few standard non-microfluidic methods for generating asymmetric vesicles. We hope to highlight the improved capability in obtaining asymmetric vesicles through a variety of methods and encourage the wider scientific community to adopt some of these for their own work.

Design and optimization of a novel herbosomal-loaded PEG-poloxamer topical formulation for the treatment of cold injuries: a quality-by-design approach

The spectrum of cold injuries ranges from frostnip, chilblains to severe frostbite. Cold injuries occur upon prolonged exposure to freezing temperature and are pathologically a combination of ice crystal formation in the tissue resulting in inflammation, thrombosis and ischemia in the extremities, often necessitating limb amputation in extreme cases due to tissue necrosis. Severe forms of frostbite are a cause of major concern to patients as well as the treating physician. Due to the lack of effective treatment modalities and paucity of research on prophylaxis and therapeutics of cold injuries, we developed a novel herbosomal-loaded PEG-poloxamer topical formulation (n-HPTF) employing quality-by-design (QBD) approach. Natural compounds exhibiting potent therapeutic potential for the management of cold injuries were incorporated in novel lipid vesicles (herbosomes) loaded in PEG-poloxamer polymers. The herbosomal formulation effectively creates an occlusion barrier that promotes epithelial regeneration, desmosome scale-up and angiogenesis and thus promotes rapid healing, indicating controlled release of herbosomes. Optimized novel herbosomes showed entrapment efficiency > 90% and < 300 nm mean particle size and in vitro drug permeation of about 2 µg/cm² followed Higuchi's release kinetics. Skin irritancy study on female Sprague-Dawley rats showed no edema or erythema. In vivo bio-efficacy study revealed significant efficacy (p < 0.05) when compared to the standard treatment groups. Graphical abstract presenting the designing and optimization of novel herbosomal-loaded PEG-poloxamer topical formulation (n-HPTF) and predictive model for the in vivo study of the developed n-HPTF on cold injury rat skin model.

Pickering Dry Emulsion System for Improved Oral Delivery of Fenofibrate

The current study reports a Pickering dry emulsion (PDE) system for improved oral delivery of fenofibrate, a poorly water-soluble model drug. The silica nanoparticles were modified by surface modifiers and explored as a stabilizer for emulsion. The wetting property of modified silica nanoparticles was evaluated by contact angle study. Emulsion was spray-dried to obtain PDE. PDE was evaluated for particle size analysis, drug loading, TGA, DSC, XRPD, FEG-SEM, in vitro dissolution study, and in vivo pharmacodynamic study. The particle size of liquid emulsion was found within the range of 0.3-0.6 μm; after spray drying, the particles agglomerated and exhibited an increase in particle size (1.5 μm). The high drug loading (13% w/w) was found in PDE. DSC and XRD study confirmed the amorphous form of fenofibrate. SEM study showed the formation of a spherical porous microcapsule structure. In vitro dissolution exhibited significant enhancement in drug release for the PDE system as compared to plain fenofibrate. The PDE significantly lowered serum lipid level as compared to plain fenofibrate in a Triton-based hypercholesterolemia model in rats, which ultimately confirmed the enhancement in bioavailability. Thus, the PDE system has good potential in the drug delivery area.

Advances in Nanomedicine Design: Multidisciplinary Strategies for Unmet Medical Needs

Globally, a rising burden of complex diseases takes a heavy toll on human lives and poses substantial clinical and economic challenges. This review covers nanomedicine and nanotechnology-enabled advanced drug delivery systems (DDS) designed to address various unmet medical needs. Key nanomedicine and DDSs, currently employed in the clinic to tackle some of these diseases, are discussed focusing on their versatility in diagnostics, anticancer therapy, and diabetes management. First-hand experiences from our own laboratory and the work of others are presented to provide insights into strategies to design and optimize nanomedicine- and nanotechnology-enabled DDS for enhancing therapeutic outcomes. Computational analysis is also briefly reviewed as a technology for rational design of controlled release DDS. Further explorations of DDS have illuminated the interplay of physiological barriers and their impact on DDS. It is demonstrated how such delivery systems can overcome these barriers for enhanced therapeutic efficacy and how new perspectives of next-generation DDS can be applied clinically.

Low-Frequency Sonophoresis as an Active Approach to Potentiate the Transdermal Delivery of Agomelatine-Loaded Novasomes: Design, Optimization, and Pharmacokinetic Profiling in Rabbits

The first melatonergic antidepressant drug, agomelatine (AGM), is commonly used for controlling major depressive disorders. AGM suffers low (< 5%) oral bioavailability owing to the hepatic metabolism. The current work investigated the potential of low-frequency sonophoresis on enhancing transdermal delivery of AGM-loaded novasomes and, hence, bioavailability of AGM. Drug-loaded novasomes were developed using free fatty acid (stearic acid or oleic acid), surfactant (span 60 or span 80), and cholesterol via thin-film hydration technique. The systems (N1-N16) were assessed for zeta potential (ZP), particle size (PS), encapsulation efficiency (EE%), and drug percent released after 0.5 h (Q_0.5 h) and 8 h (Q_8h), drug-crystallinity, morphology, and ex vivo drug permeation. Skin pre-treatment with low-frequency ultrasound (LFU) waves, via N13-novasomal gel systems, was optimized to enhance ex vivo drug permeation. Influences of LFU mode (continuous or pulsed), duty cycle (50% or 100%), and application period (10 or 15 min) were optimized. The pharmacokinetics of the optimized system (N13-LFU-C4) was assessed in rabbits. N13 was the best achieved novasomal system with respect to PS (471.6 nm), ZP (- 63.6 mv), EE% (60.5%), Q_0.5 h (27.8%), Q_8h (83.9%), flux (15.5 μg/cm²/h), and enhancement ratio (6.9). N13-LFU-C4 was the optimized novasomal gel system (desirability; 0.997) which involves skin pre-treatment with LFU in a continuous mode, at 100% duty cycle, for 15 min. Compared to AGM dispersion, the significantly (P < 0.05) higher flux (26.7 μg/cm²/h), enhancement ratio (11.9), C_max (118.23 ng/mL), and relative bioavailability (≈ 8.6 folds) could elucidate the potential of N13-LFU-C4 system in improving transdermal drug permeability and bioavailability.

Optimizing the Design of Blood-Brain Barrier-Penetrating Polymer-Lipid-Hybrid Nanoparticles for Delivering Anticancer Drugs to Glioblastoma

PURPOSE

Chemotherapy for glioblastoma multiforme (GBM) remains ineffective due to insufficient penetration of therapeutic agents across the blood-brain barrier (BBB) and into the GBM tumor. Herein, is described, the optimization of the lipid composition and fabrication conditions for a BBB- and tumor penetrating terpolymer-lipid-hybrid nanoparticle (TPLN) for delivering doxorubicin (DOX) to GBM.

METHODS

The composition of TPLNs was first screened using different lipids based on nanoparticle properties and in vitro cytotoxicity by using 2³ full factorial experimental design. The leading DOX loaded TPLNs (DOX-TPLN) were prepared by further optimization of conditions and used to study cellular uptake mechanisms, in vitro cytotoxicity, three-dimensional (3D) glioma spheroid penetration, and in vivo biodistribution in a murine orthotopic GBM model.

RESULTS

Among various lipids studied, ethyl arachidate (EA) was found to provide excellent nanoparticle properties e.g., size, polydispersity index (PDI), zeta potential, encapsulation efficiency, drug loading, and colloidal stability, and highest anticancer efficacy for DOX-TPLN. Further optimized EA-based TPLNs were prepared with an optimal particle size (103.8 ± 33.4 nm) and PDI (0.208 ± 0.02). The resultant DOX-TPLNs showed ~ sevenfold higher efficacy than free DOX against human GBM U87-MG-RED-FLuc cells in vitro. The interaction between the TPLNs and the low-density lipoprotein receptors also facilitated cellular uptake, deep penetration into 3D glioma spheroids, and accumulation into the in vivo brain tumor regions of DOX-TPLNs.

CONCLUSION

This work demonstrated that the TPLN system can be optimized by rational selection of lipid type, lipid content, and preparation conditions to obtain DOX-TPLN with enhanced anticancer efficacy and GBM penetration and accumulation.

Strategies for Preparing Different Types of Lipid Polymer Hybrid Nanoparticles in Targeted Tumor Therapy

At present, cancer is one of the most common diseases in the world, causing a large number of deaths and seriously affecting people's health. The traditional treatment of cancer is mainly surgery, radiotherapy or chemotherapy. Conventional chemotherapy is still an important treatment, but it has some shortcomings, such as poor cell selectivity, serious side effects, drug resistance and so on. Nanoparticle administration can improve drug stability, reduce toxicity, prolong drug release time, prolong system half-life, and bring broad prospects for tumor therapy. Lipid polymer hybrid nanoparticles (LPNs), which combine the advantages of polymer core and phospholipid shell to form a single platform, have become multi-functional drug delivery platforms. This review introduces the basic characteristics, structure and preparation methods of LPNs, and discusses targeting strategies of LPNs in tumor therapy in order to overcome the defects of traditional drug therapy.

RAFT polymerization mediated core-shell supramolecular assembly of PEGMA-co-stearic acid block co-polymer for efficient anticancer drug delivery

In this work, core-shell supramolecular assembly polymeric nano-architectures containing hydrophilic and hydrophobic segments were synthesized via reversible addition fragmentation chain transfer (RAFT) polymerization. Herein, polyethylene glycol methyl ether methacrylate (PEGMA), and stearic acid were used to synthesize the poly(PEGMA) homopolymer and stearyl ethyl methacrylate (SEMA), respectively. Then, PEGMA and SEMA were polymerized through controlled RAFT polymerization to obtain the final diblock copolymer, poly(PEGMA-co-SEMA) (BCP). Model anticancer drug, doxorubicin (DOX) was loaded on BCPs. Interestingly, efficient DOX release was observed at acidic pH, similar to the cancerous environment pH level. Significant cellular uptake of DOX loaded BCP50 (BCP50-DOX) was observed in MDA-MB-231 triple negative breast cancer cells and resulted in a 35 fold increase in anticancer activity against MDA MB-231 cells compared to free DOX. Scanning electron microscopy (SEM) imaging confirmed the apoptosis mediated cellular death. These core-shell supramolecular assembly polymeric nano-architectures may be an efficient anti-cancer drug delivery system in the future.

Lipid-polymer hybrid nanoparticles in cancer therapy: current overview and future directions

Cancer remains one of the leading cause of death worldwide. Current therapies are still ineffective in completely eradicating the disease. In the last two decades, the use of nanodelivery systems has emerged as an effective way to potentiate the therapeutic properties of anti-cancer drugs by improving their solubility and stability, prolong drug half-lives in plasma, minimize drug’s toxicity by reducing its off-target distribution, and promote drugs’ accumulation at the desired target site. Liposomes and polymer nanoparticles are the most studied and have demonstrated to be the most effective delivery systems for anti-cancer drugs. However, both liposomes and polymeric nanoparticles suffer from limitations, including high instability, rapid drug release, limited drug loading capacity, low biocompatibility and lack of suitability for large-scale production. To overcome these limitations, lipid-polymer hybrid nanoparticles (LPHNPs) have been developed to merge the advantages of both lipid- and polymer-based nanocarriers, such as high biocompatibility and stability, improved drug loading and controlled release, as well as increased drug half-lives and therapeutic efficacy. This review provides an overview on the synthesis, properties and application of LPHNPs for cancer therapy.

Co-Amorphous Formulations of Furosemide with Arginine and P-Glycoprotein Inhibitor Drugs

In this study, the amino acid arginine (ARG) and P-glycoprotein (P-gp) inhibitors verapamil hydrochloride (VER), piperine (PIP) and quercetin (QRT) were used as co-formers for co-amorphous mixtures of a Biopharmaceutics classification system (BCS) class IV drug, furosemide (FUR). FUR mixtures with VER, PIP and QRT were prepared by solvent evaporation, and mixtures with ARG were prepared by spray drying in 1:1 and 1:2 molar ratios. The solid-state properties of the mixtures were characterized with X-ray powder diffraction (XRPD), Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) in stability studies under different storage conditions. Simultaneous dissolution/permeation studies were conducted in side-by-side diffusion cells with a PAMPA (parallel artificial membrane permeability assay) membrane as a permeation barrier. It was observed with XRPD that ARG, VER and PIP formed co-amorphous mixtures with FUR at both molar ratios. DSC and FTIR revealed single glass transition values for the mixtures (except for FUR:VER 1:2), with the formation of intermolecular interactions between the components, especially salt formation between FUR and ARG. The co-amorphous mixtures were found to be stable for at least two months under an elevated temperature/humidity, except FUR:ARG 1:2, which was sensitive to humidity. The dissolution/permeation studies showed that only the co-amorphous FUR:ARG mixtures were able to enhance both the dissolution and permeation of FUR. Thus, it is concluded that formulating co-amorphous salts with ARG may be a promising option for poorly soluble/permeable FUR.

Influence of Terpene Type on the Release from an O/W Nanoemulsion: Experimental and Theoretical Studies

The interaction between a drug molecule and its carrier’s components is an important factor which influences the drug release profile. For this purpose, molecular dynamics (MD) may be the in silico tool which can help to understand the mechanism of drug loading/release. The aim of this work is to explain the effect of interactions between different types of terpenes, namely perillyl alcohol, forskolin, ursolic acid, and the nanoemulsion droplet core, on the release by means of experimental and theoretical studies. The basic nanoemulsion was composed of caprylic/capric triglyceride as the oil phase, polysorbate 80 as the emulsifier, and water. The in vitro release tests from a terpene-loaded nanoemulsion were carried out to determine the release profiles. The behavior of terpenoids in the nanoemulsion was also theoretically investigated using the molecular dynamics method. The forskolin-loaded nanoemulsion showed the highest percentage of drug release (almost 80% w/w) in contrast to ursolic acid and perillyl alcohol-loaded nanoemulsions (about 53% w/w and 19% w/w, respectively). The results confirmed that the kinetic model of release was terpene-type dependent. The zero-order model was the best to describe the ursolic acid release profile, while the forskolin and the perillyl alcohol followed a first-order and Higuchi model, respectively. Molecular dynamics simulations, especially energetical analysis, confirmed that the driving force of terpenes diffusion from nanoemulsion interior was their interaction energy with a surfactant.

Long-Acting Paliperidone Parenteral Formulations Based on Polycaprolactone Nanoparticles; the Influence of Stabilizer and Chitosan on In Vitro Release, Protein Adsorption, and Cytotoxicity

Long-acting preparations containing the antipsychotic paliperidone for intramuscular injection has drawn considerable attention to achieve harmless long-term treatment. This study aimed to develop paliperidone loaded polycaprolactone (PCL) nanoparticles and investigate the influence of PCL/drug ratio, stabilizer type, and chitosan coating on physicochemical properties, protein adsorption, and cellular toxicity. Results showed that chitosan coating produced enlarged particle sizes, shifted the surface charges from negative into positive and did not influence encapsulation efficiencies. Chitosan coating relatively sustained the drug release especially in pluronic stabilized formulations. Pluronic F127 based formulations exhibited the least protein adsorption (384.3 μg/mL). Chitosan coating of Tween 80 and polyvinyl alcohol stabilized formulations significantly (p < 0.05) increased protein adsorption. Cellular viability was concentration-dependent and negatively affected by stabilizers. All formulations did not show cellular death at 1.56 μg/mL. Inflammatory responses and oxidative stress were less affected by Tween 80 compared with other stabilizers. Chitosan minimized all aspects of cellular toxicity. Collectively, stabilizer type and chitosan coating play critical roles in developing safe and effective long-acting PCL nanoparticles intended for parenteral drug delivery. The coated formulations containing Tween 80 and Pluronic F127 as stabilizers are warranted a future in vivo study to delineate its safety and efficacy profiles.

Lipid-chitosan hybrid nanoparticles for controlled delivery of cisplatin

Lipid-polymer hybrid nanoparticles (LPHNP) are delivery systems for controlled drug delivery at tumor sites. The superior biocompatible properties of lipids and structural advantages of polymers can be obtained using this system for controlled drug delivery. In this study, cisplatin-loaded lipid-chitosan hybrid nanoparticles were formulated by the single step ionic gelation method based on ionic interaction of positively charged chitosan and negatively charged lipid. Formulations with various chitosan to lipid ratios were investigated to obtain the optimal particle size, encapsulation efficiency, and controlled release pattern. Transmission electron microscope and dynamic light scattering analysis demonstrated a size range of 181–245 nm and a zeta potential range of 20–30 mV. The stability of the formulation was demonstrated by thermal studies. Cytotoxicity and cellular interaction of cisplatin-loaded LPHNP were investigated using in vitro cell-based assays using the A2780 ovarian carcinoma cell line. The pharmacokinetics study in rabbits supported a controlled delivery of cisplatin with enhanced mean residence time and half-life. These studies suggest that cisplatin loaded LPHNP have promise as a platform for controlled delivery of cisplatin in cancer therapy.

Brain targeting stealth lipomers of combined antiepileptic-anti-inflammatory drugs as alternative therapy for conventional anti-Parkinson's

This study presents an alternative therapy to conventional anti-Parkinson's treatment strategies; where motor and non-motor symptomatic complications are considered. Thus; providing sustainability, patient compliance, therapeutic safety and efficiency, based on triggering secretion of endogenous dopamine (DA). Exogenous DA has long been considered the best therapy, however, its poor blood brain barrier (BBB) permeability, fluctuated plasma levels, and non-motor complications negligence, decreased response to therapy with time. Consequently; brain targeting Tween®80-coated pegylated lipomers were tailored for intravenous administration (IV) of L-Dopa, and two drugs of reported neuroprotective effect: lamotrigine (LTG) and tenoxicam (TX). Single-step nanoprecipitation method was used; for its reproducibility and ease of scaling-up. Formulation targeting and anti-PD efficiency was evaluated against marketed standards and L-Dopa. In-vitro and in-vivo pharmacokinetic and dynamic studies were carried out for setting optimization standards upon varying inter-components ratio. Results revealed that lipomers are, generally, significantly efficient in brain targeting compared to oral tablets. LTG-lipomers (LF20) showed the maximum anti-PD compared to its TX and L-Dopa analogues. Combining LTG and TX had synergistic effect; highlighting a new prescription for both drugs. Thus; offering a safe, targeted, and therapeutically efficient sustained dosage form, capable of mitigating PD risk and treating it though weekly administration. Hence; presenting a novel promising anti-neurodegenerative strategy; on employing various mechanisms that were previously achieved through additional therapeutic supplements.

Lipid-polymer hybrid nanoparticles for controlled delivery of hydrophilic and lipophilic doxorubicin for breast cancer therapy

Background: Lipid polymer hybrid nanoparticles (LPHNPs) for the controlled delivery of hydrophilic doxorubicin hydrochloride (DOX.HCl) and lipophilic DOX base have been fabricated by the single step modified nanoprecipitation method.

Materials and methods: Poly (D, L-lactide-co-glicolide) (PLGA), lecithin, and 1,2-distearoyl-Sn-glycero-3-phosphoethanolamine-N-[methoxy (polyethylene glycol)-2000 (DSPE-PEG 2000) were selected as structural components.

Results: The mean particle size was 173–208 nm, with an encapsulation efficiency of 17.8±1.9 to 43.8±4.4% and 40.3±0.6 to 59. 8±1.4% for DOX.HCl and DOX base, respectively. The drug release profile was in the range 33–57% in 24 hours and followed the Higuchi model (R²=0.9867–0.9450) and Fickian diffusion (n<0.5). However, the release of DOX base was slower than DOX.HCl. The in vitro cytotoxicity studies and confocal imaging showed safety, good biocompatibility, and a higher degree of particle internalization. The higher internalization of DOX base was attributed to higher permeability of lipophilic component and better hydrophobic interaction of particles with cell membranes. Compared to the free DOX, the DOX.HCl and DOX base loaded LPHNPs showed higher antiproliferation effects in MDA-MB231 and PC3 cells.

Conclusion: Therefore, LPHNPs have provided a potential drug delivery strategy for safe, controlled delivery of both hydrophilic and lipophilic form of DOX in cancer cells.

Lipomers (Lipid-polymer Hybrid Particles) of Vardenafil Hydrochloride: a Promising Dual Platform for Modifying the Drug Release Rate and Enhancing Its Oral Bioavailability

Vardenafil hydrochloride is commonly used for the curing of erectile dysfunction. VAR suffers certain limitations: (i) short elimination half-life (4-5 h), (ii) low aqueous solubility (0.11 mg/mL), (iii) susceptibility to extensive first-pass metabolism and drug efflux transporters (P-glycoprotein), and (iv) limited (15%) oral bioavailability. The current study focused on the development of VAR lipomers as promising modified release systems able to enhance oral bioavailability. VAR-lipomers (lipid-polymer complexes) were successfully developed by a modified precipitation technique employing a lipid (polyglyceryl-6-distearate or glyceryl tristearate) and an amphiphilic polymer (Gantrez®). Three VAR:lipid ratios [1:1, 1:2, and 1:3] and three VAR:Gantrez® ratios [4:1, 2:1, and 1:1] were investigated. Solid-state characterization studies involved differential scanning calorimetry (DSC), X-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) spectroscopy. The systems were assessed for particle size, polydispersity index (PDI), zeta-potential, VAR entrapment-efficiency (EE%), morphology, and VAR released % after 2 h (Q_2h) and 8 h (Q_8h). The best-achieved system (the highest desirability) was promoted for pharmacokinetic studies in fasted rabbits. Statistical analysis of data revealed that L9 system (PGDS, VAR, and Gantrez®; 3:1:1, respectively) had the highest desirability (0.85) with respect to spherical particle size (622.15 nm), PDI (0.11), zeta-potential (-27.90 mV), EE% (62.80%), Q_2h (43.45%), and Q_8h (77.40%). With respect to Levitra® tablets, the significantly higher relative bioavailability (170%), delayed T_max, and extended MRT_(0-∞) clarified the dual ability of L9 system. Lipomers are emerging systems capable of modifying the rate of VAR release and promoting its oral bioavailability.

Importance of integrating nanotechnology with pharmacology and physiology for innovative drug delivery and therapy - an illustration with firsthand examples

Nanotechnology has been applied extensively in drug delivery to improve the therapeutic outcomes of various diseases. Tremendous efforts have been focused on the development of novel nanoparticles and delineation of the physicochemical properties of nanoparticles in relation to their biological fate and functions. However, in the design and evaluation of these nanotechnology-based drug delivery systems, the pharmacology of delivered drugs and the (patho-)physiology of the host have received less attention. In this review, we discuss important pharmacological mechanisms, physiological characteristics, and pathological factors that have been integrated into the design of nanotechnology-enabled drug delivery systems and therapies. Firsthand examples are presented to illustrate the principles and advantages of such integrative design strategies for cancer treatment by exploiting 1) intracellular synergistic interactions of drug-drug and drug-nanomaterial combinations to overcome multidrug-resistant cancer, 2) the blood flow direction of the circulatory system to maximize drug delivery to the tumor neovasculature and cells overexpressing integrin receptors for lung metastases, 3) endogenous lipoproteins to decorate nanocarriers and transport them across the blood-brain barrier for brain metastases, and 4) distinct pathological factors in the tumor microenvironment to develop pH- and oxidative stress-responsive hybrid manganese dioxide nanoparticles for enhanced radiotherapy. Regarding the application in diabetes management, a nanotechnology-enabled closed-loop insulin delivery system was devised to provide dynamic insulin release at a physiologically relevant time scale and glucose levels. These examples, together with other research results, suggest that utilization of the interplay of pharmacology, (patho-)physiology and nanotechnology is a facile approach to develop innovative drug delivery systems and therapies with high efficiency and translational potential.

Lipid-polymer hybrid nanocarriers for delivering cancer therapeutics

Cancer remained a major cause of death providing diversified challenges in terms of treatment including non-specific toxicity, chemoresistance and relapse. Nanotechnology- based delivery systems grabbed tremendous attention for delivering cancer therapeutics as they provide benefits including controlled drug release, improved biological half-life, reduced toxicity and targeted delivery. Majority of the nanocarriers consists of either a polymer or a lipid component along with other excipients to stabilize the colloidal system. Lipid-based systems provide advantages like better entrapment efficiency, scalability and low- cost raw materials, however, suffer from limitations including instability, a burst release of the drug, and limited surface functionalization. On the other hand, polymeric systems provide an excellent diversity of chemical modifications, stability, controlled release, however limited drug loading capacities and scale up limit their use. Hybrid nanocarriers consisting of lipid and polymer were able to overcome some of these disadvantages while retaining the advantages of both the systems. Designing a stable lipid-polymer hybrid system requires a thorough understanding of the material properties and their behavior in in vitro and in vivo environments. This review highlights the current status and future prospects of lipid-polymer hybrid systems with a particular focus on cancer nanotherapeutics.

Engineering of small interfering RNA-loaded lipidoid-poly(DL-lactic-co-glycolic acid) hybrid nanoparticles for highly efficient and safe gene silencing: A quality by design-based approach

Safety and efficacy of therapeutics based on RNA interference, e.g., small interfering RNA (siRNA), are dependent on the optimal engineering of the delivery technology, which is used for intracellular delivery of siRNA to the cytosol of target cells. We investigated the hypothesis that commonly used and poorly tolerated cationic lipids might be replaced with more efficacious and safe lipidoids as the lipid component of siRNA-loaded lipid-polymer hybrid nanoparticles (LPNs) for achieving more efficient gene silencing at lower and safer doses. However, formulation design of such a complex formulation is highly challenging due to a strong interplay between several contributing factors. Hence, critical formulation variables, i.e. the lipidoid content and siRNA:lipidoid ratio, were initially identified, followed by a systematic quality-by-design approach to define the optimal operating space (OOS), eventually resulting in the identification of a robust, highly efficacious and safe formulation. A 17-run design of experiment with an I-optimal approach was performed to systematically assess the effect of selected variables on critical quality attributes (CQAs), i.e. physicochemical properties (hydrodynamic size, zeta potential, siRNA encapsulation/loading) and the biological performance (in vitro gene silencing and cell viability). Model fitting of the obtained data to construct predictive models revealed non-linear relationships for all CQAs, which can be readily overlooked in one-factor-at-a-time optimization approaches. The response surface methodology further enabled the identification of an OOS that met the desired quality target product profile. The optimized lipidoid-modified LPNs revealed more than 50-fold higher in vitro gene silencing at well-tolerated doses and approx. a twofold increase in siRNA loading as compared to reference LPNs modified with the commonly used cationic lipid dioleyltrimethylammonium propane (DOTAP). Thus, lipidoid-modified LPNs show highly promising prospects for efficient and safe intracellular delivery of siRNA.

Lipid-polymer hybrid nanoparticles: Development & statistical optimization of norfloxacin for topical drug delivery system

Poly lactic acid is a biodegradable, biocompatible, and non-toxic polymer, widely used in many pharmaceutical preparations such as controlled release formulations, parenteral preparations, surgical treatment applications, and tissue engineering. In this study, we prepared lipid-polymer hybrid nanoparticles for topical and site targeting delivery of Norfloxacin by emulsification solvent evaporation method (ESE). The design of experiment (DOE) was done by using software to optimize the result, and then a surface plot was generated to compare with the practical results. The surface morphology, particle size, zeta potential and composition of the lipid-polymer hybrid nanoparticles were characterized by SEM, TEM, AFM, and FTIR. The thermal behavior of the lipid-polymer hybrid nanoparticles was characterized by DSC and TGA. The prepared lipid-polymer hybrid nanoparticles of Norfloxacin exhibited an average particle size from 178.6 ± 3.7 nm to 220.8 ± 2.3 nm, and showed very narrow distribution with polydispersity index ranging from 0.206 ± 0.36 to 0.383 ± 0.66. The surface charge on the lipid-polymer hybrid nanoparticles were confirmed by zeta potential, showed the value from +23.4 ± 1.5 mV to +41.5 ± 3.4 mV. An Antimicrobial study was done against Staphylococcus aureus and Pseudomonas aeruginosa, and the lipid-polymer hybrid nanoparticles showed potential activity against these two. Lipid-polymer hybrid nanoparticles of Norfloxacin showed the %cumulative drug release of 89.72% in 24 h. A stability study of the optimized formulation showed the suitable condition for the storage of lipid-polymer hybrid nanoparticles was at 4 ± 2 °C/60 ± 5% RH. These results illustrated high potential of lipid-polymer hybrid nanoparticles Norfloxacin for usage as a topical antibiotic drug carriers.

•

Efficient topical drug delivery systems of norfloxacin have been synthesized.

•

Norfloxacin loaded to the core of lipid- polymer hybrid nanoparticles were prepared.

•

The formulations were optimized by factorial design and characterization techniques.

•

A unique formulation of norfloxacin that offer prolonged and control delivery.

Design of nanocarriers for nanoscale drug delivery to enhance cancer treatment using hybrid polymer and lipid building blocks

Polymer-lipid hybrid nanoparticles (PLN) are an emerging nanocarrier platform made from building blocks of polymers and lipids. PLN integrate the advantages of biomimetic lipid-based nanoparticles (i.e. solid lipid nanoparticles and liposomes) and biocompatible polymeric nanoparticles. PLN are constructed from diverse polymers and lipids and their numerous combinations, which imparts PLN with great versatility for delivering drugs of various properties to their nanoscale targets. PLN can be classified into two types based on their hybrid nanoscopic structure and assembly methods: Type-I monolithic matrix and Type-II core-shell systems. This article reviews the history of PLN development, types of PLN, lipid and polymer candidates, fabrication methods, and unique properties of PLN. The applications of PLN in delivery of therapeutic or imaging agents alone or in combination for cancer treatment are summarized and illustrated with examples. Important considerations for the rational design of PLN for advanced nanoscale drug delivery are discussed, including selection of excipients, synthesis processes governing formulation parameters, optimization of nanoparticle properties, improvement of particle surface functionality to overcome macroscopic, microscopic and cellular biological barriers. Future directions and potential clinical translation of PLN are also suggested.

Development of novel self-assembled ES-PLGA hybrid nanoparticles for improving oral absorption of doxorubicin hydrochloride by P-gp inhibition: In vitro and in vivo evaluation

To increase the encapsulation efficiency and oral absorption of doxorubicin hydrochloride (DOX), a novel drug delivery system of enoxaparin sodium-PLGA hybrid nanoparticles (EPNs) was successfully designed. By introducing the negative polymer of enoxaparin sodium (ES) to form an electrostatic complex with the cationic drug, DOX, the encapsulation efficiency (93.78%) of DOX was significantly improved. The X-ray diffraction (XRD) results revealed that the DOX-ES complex was in an amorphous form. An in vitro release (pH6.8 PBS) study showed the excellent sustained-release characteristics of DOX-loaded EPNs (DOX-EPNs). In addition, in situ intestinal perfusion and intestinal biodistribution experiments demonstrated the improved membrane permeability and intestinal wall bioadhesion of DOX-EPNs, and caveolin- and clathrin-mediated endocytosis pathways were the main mechanisms responsible. The cytotoxicity of DOX was significantly increased by EPNs in Caco-2 cells, compared with DOX-Sol. Confocal laser scanning microscope (CLSM) images confirmed that the amount of DOX-EPNs internalized by Caco-2 cells was higher than that of DOX-Sol showing that P-glycoprotein-mediated drug efflux was reduced by the introduction of EPNs. The qualitative detection of transcytosis demonstrated the ability of the nanoparticles (NPs) to cross Caco-2 cell monolayers. An in vivo toxicity experiment demonstrated that DOX-EPNs reduced cardiac and renal toxic effects and were biocompatible. An in vivo pharmacokinetics study showed that the AUC_(0-t) and t_1/2 of DOX-EPNs were increased to 3.63-fold and 2.47-fold in comparison with DOX solution (DOX-Sol), respectively. All these results indicated that the novel EPNs were an excellent platform to improve the encapsulation efficiency of an aqueous solution of this antitumor drug and its oral bioavailability.

Building the design, translation and development principles of polymeric nanomedicines using the case of clinically advanced poly(lactide(glycolide))-poly(ethylene glycol) nanotechnology as a model: An industrial viewpoint

The design of the first polymeric nanoparticles could be traced back to the 1970s, and has thereafter received considerable attention, as evidenced by the significant increase of the number of articles and patents in this area. This review article is an attempt to take advantage of the existing literature on the clinically tested and commercialized biodegradable PLA(G)A-PEG nanotechnology as a model to propose quality building and outline translation and development principles for polymeric nano-medicines. We built such an approach from various building blocks including material design, nano-assembly - i.e. physicochemistry of drug/nano-object association in the pharmaceutical process, and release in relevant biological environment - characterization and identification of the quality attributes related to the biopharmaceutical properties. More specifically, as envisaged in a translational approach, the reported data on PLA(G)A-PEG nanotechnology have been structured into packages to evidence the links between the structure, physicochemical properties, and the in vitro and in vivo performances of the nanoparticles. The integration of these bodies of knowledge to build the CMC (Chemistry Manufacturing and Controls) quality management strategy and finally support the translation to proof of concept in human, and anticipation of the industrialization takes into account the specific requirements and biopharmaceutical features attached to the administration route. From this approach, some gaps are identified for the industrial development of such nanotechnology-based products, and the expected improvements are discussed. The viewpoint provided in this article is expected to shed light on design, translation and pharmaceutical development to realize their full potential for future clinical applications.

Synergistic and complete reversal of the multidrug resistance of mitoxantrone hydrochloride by three-in-one multifunctional lipid-sodium glycocholate nanocarriers based on simultaneous BCRP and Bcl-2 inhibition

Multidrug resistance (MDR) is a severe obstacle to successful chemotherapy due to its complicated nature that involves multiple mechanisms, such as drug efflux by transporters (P-glycoprotein and breast cancer resistance protein, BCRP) and anti-apoptotic defense (B-cell lymphoma, Bcl-2). To synergistically and completely reverse MDR by simultaneous inhibition of pump and non-pump cellular resistance, three-in-one multifunctional lipid-sodium glycocholate (GcNa) nanocarriers (TMLGNs) have been designed for controlled co-delivery of water-soluble cationic mitoxantrone hydrochloride (MTO), cyclosporine A (CsA – BCRP inhibitor), and GcNa (Bcl-2 inhibitor). GcNa and dextran sulfate were incorporated as anionic compounds to enhance the encapsulation efficiency of MTO (up to 97.8%±1.9%) and sustain the release of cationic MTO by electrostatic interaction. The results of a series of in vitro and in vivo investigations indicated that the TMLGNs were taken up by the resistant cancer cells by an endocytosis pathway that escaped the efflux induced by BCRP, and the simultaneous release of CsA with MTO further efficiently inhibited the efflux of the released MTO by BCRP; meanwhile GcNa induced the apoptosis process, and an associated synergistic antitumor activity and reversion of MDR were achieved because the reversal index was almost 1.0.

Exploitation of lipid-polymeric matrices at nanoscale for drug delivery applications

INTRODUCTION

Progress in drug delivery and a better quality of life for patients, relies on the development of new and suitable drug carrier systems, with unequivocal therapeutic benefits, low systemic toxicity and reduced side effects. Lipid-polymeric nanoparticles have been explored to produce nanocarriers due to their features and applications such as high drug entrapment, physical-chemical stability and controlled release properties.

AREAS COVERED

In this review, we describe several hybrid nanoparticles obtained from mixing a polymer with a lipid matrix. This association can potentiate the efficacy of drug delivery systems, due to the enhancement of encapsulation efficiency and loading capacity, tailoring the drug release according to the therapeutic purpose, and improving the drug uptake by targeting it to specific receptors. Contrary to lipid nanoparticles, these hybrid nanoparticles can decrease the initial burst release and promote a more sustained and localized release of the drug.

EXPERT OPINION

Lipid-polymeric nanoparticles are versatile vehicles for drug delivery by different administration routes in the treatment of multiple diseases. Different solid lipids, polymers, surfactants and techniques for producing these carriers have been investigated, revealing the importance of their composition to achieve optimal characteristics to drug delivery.

Role of Four Different Kinds of Polyethylenimines (PEIs) in Preparation of Polymeric Lipid Nanoparticles and Their Anticancer Activity Study

A series of polyethylenimines-coated poly(d,l-lactide-co-glycolide)/lipid nanoparticles (PPLs) were fabricated for delivering paclitaxel via a simple nano-precipitation method. Four kinds of polyethylenimines (PEIs) (800 Da-, 2000 Da- and 25 kDa-branched PEIs, and 25 kDa-linear PEI) were selected as a polymeric coating for the nanoparticles. The PPLs were evaluated for their cytotoxic effects towards tumor cells. The nanoparticles were uniform spheres with particle sizes ranging from 135.8 to 535.9 nm and zeta potentials between 13.5 and 45.4 mV. The content of lipids and PEIs were optimized at lipids content from 0 to 40% and PEI content from 2.5% to 10%, respectively. At 20% lipid content and 5% PEI content, the formulation was found to be optimal. In vitro experiments showed that 25 kDa-branched PEI coated PLGA/lipid nanoparticles (25k-bPPLs) had higher cytotoxicity than other PPLs in several cancer cell lines. Meanwhile, 25k-bPPLs maintained high cellular delivery efficiency without excessive toxicity, which was confirmed by confocal microscopy and flow cytometry analyses. Furthermore, 25k-bPPLs displayed excellent colloidal stability in pH 7.4 PBS. In conclusion, 25k-bPPLs are promising drug delivery vehicles for cancer therapeutics.

Nanostructured lipid-carrageenan hybrid carriers (NLCCs) for controlled delivery of mitoxantrone hydrochloride to enhance anticancer activity bypassing the BCRP-mediated efflux

Novel nanostructured lipid-carrageenan hybrid carriers (NLCCs) were exploited for controlled delivery of water soluble chemotherapeutic agent mitoxantrone hydrochloride (MTO) with high loading capacity, sustained release property, and potential for improving oral bioavailability and antitumor efficacy. By introducing the negative polymer of carrageenan, MTO was highly incorporated into NLCCs with encapsulation efficiency of 95.8% by electrostatic interaction. In vivo pharmacokinetics of MTO solution (MTO-Sol) and MTO-NLCCs in rats demonstrated that the apparent bioavailability of MTO-NLCCs was increased to approximate 3.5-fold compared to that of MTO-Sol. The cytotoxicity investigations by MTT method indicated that NLCCs could significantly enhanced the antitumor efficacy against resistant MCF-7/MX cells. The relative cellular association of MTO-NLCCs was 9.2-fold higher than that of MTO-Sol in breast cancer resistance protein (BCRP) over-expressing MCF-7/MX cells, implying that BCRP-mediated drug efflux was diminished by the introduction of NLCCs. The endocytosis inhibition study implied that the NLCCs entered the MCF-7/MX cells by clathrin-mediated endocytosis process, which can bypass the efflux of MTO mediated by BCRP. The new developed NLCCs provide an effective strategy for oral delivery of water-soluble MTO with improved encapsulation efficiency, oral bioavailability, and cytotoxicity against resistant breast cancer cells.

Interpenetrating polymer networks of poly(methacrylic acid) and polyacrylamide: synthesis, characterization and potential application for sustained drug delivery

Novel interpenetrating polymer networks (IPN) of poly(methacrylic acid) (PMAA) and polyacrylamide (PAAm) were synthesized and characterized and their potential as drug delivery system was revealed.

Poly (ɛ-caprolactone) nanoparticles of carboplatin: Preparation, characterization and in vitro cytotoxicity evaluation in U-87 MG cell lines

Carboplatin is a platinum based drug used in the treatment of several malignancies. Due to poor cellular uptake, generally, a larger dose of drug is administered to achieve therapeutic levels, causing harmful side-effects such as hematologic toxicity. In order to enhance the cellular uptake of carboplatin, we have developed carboplatin loaded nanoparticles using the biodegradable polymer poly (ɛ-caprolactone) (PCL). Nanoparticles ranging from the size of 23.77±1.37 to 96.73±2.79 nm with positive zeta potential and moderate entrapment efficiency (54.21±0.98%) were obtained. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) confirmed the spherical morphology and smooth surface of all nanoformulations. The concentrations of PCL and the stabilizer (DMAB) are found to play a role in determining the size and the entrapment efficiency of the nanoparticles. Drug release from nanoparticles followed a biphasic pattern with an initial burst release followed by a sustained release for 10h. Results of in vitro cellular uptake and cytotoxicity studies revealed that carboplatin in the form of PCL-nanoparticles were efficiently up taken and displayed profound cytotoxicity to U-87 MG (human glioma) cells than the free drug. Importantly, unlike the free carboplatin, carboplatin in the form of PCL nanoparticles did not present any haemolytic activity in rat erythrocytes, a major side effect of this chemotherapeutic drug. This suggests that poly (ɛ-caprolactone) nanoencapsulation of carboplatin might be an efficient approach to treat cancer, while reducing carboplatin induced haemolysis.