Synthesis of high loading and encapsulation efficient paclitaxel-loaded poly(n-butyl cyanoacrylate) nanoparticles via miniemulsion

Effect of polymeric stabilizers on the size and stability of PLGA paclitaxel nanoparticles

The aim of this study is to formulate polymeric paclitaxel nanoparticles with various stabilizers to improve solubility, enhance stability, maximize therapeutic efficacy and minimize detrimental toxicities of paclitaxel. In this study, trastuzumab-guided poly lactic-co-glycolic acid (PLGA)-loaded paclitaxel nanoparticles were formulated with pluronic F-127, polyvinyl alcohol (PVA), poloxamer 407, Tween-80, span 20, sodium dodecyl sulfate (SDS), and sodium lauryl sulfate (SLS) at different concentrations (0.5, 1, 1.5 and 2%) using the solvent evaporation method. The nanoparticles were evaluated for physicochemical characteristics and short and long-term stability. The optimum particle size (190 nm ± 12.42 to 350 nm ± 11.1), PDI (0.13 ± 0.02 to 0.2 ± 0.01), surface charge (-19.1mv ± 1.5 to -40.4mv ± 1.6), drug loading (2.43 to 9.5 %) and encapsulation efficiency (greater than 80 %) were obtained with these stabilizers while keeping the polymer concentration, temperature, probe size, amplitude and sonication time constant. The nanoformulations were stably stored at 4 °C. The nanoformulations of paclitaxel with pluronic F-127, polyvinyl alcohol (PVA), and poloxamer 407 were found to be more soluble, stable, uniform in physicochemical properties, and efficient in drug loading and encapsulation for improved therapeutic effects.

Nanocarriers with Multiple Cargo Load-A Comprehensive Preparation Guideline Using Orthogonal Strategies

Multifunctional nanocarriers enhance the treatment efficacy for modern therapeutics and have gained increasing importance in biomedical research. Codelivery of multiple bioactive molecules enables synergistic therapies. Coencapsulation of cargo molecules into one nanocarrier system is challenging due to different physicochemical properties of the cargo molecules. Additionally, coencapsulation of multiple molecules simultaneously shall proceed with high control and efficiency. Orthogonal approaches for the preparation of nanocarriers are essential to encapsulate sensitive bioactive molecules while preserving their bioactivity. Preparation of nanocarriers by physical processes (i.e., self-assembly or coacervation) and chemical reactions (i.e., click reactions, polymerizations, etc.) are considered as orthogonal methods to most cargo molecules. This review shall act as a guideline to allow the reader to select a suitable preparation protocol for a desired nanocarrier system. This article helps to select for combinations of cargo molecules (hydrophilic-hydrophobic, small-macro, organic-inorganic) with nanocarrier material and synthesis protocols. The focus of this article lies on the coencapsulation of multiple cargo molecules into biocompatible and biodegradable nanocarriers prepared by orthogonal strategies. With this toolbox, the selection of a preparation method for a known set of cargo molecules to prepare the desired biodegradable and loaded nanocarrier shall be provided.

Design, Preparation, and Evaluation of Osthol Poly-Butyl-Cyanoacrylate Nanoparticles with Improved In Vitro Anticancer Activity in Neuroblastoma Treatment

Osthol (osthole), known as a neuroprotective drug, has shown potent anticancer activity. However, the potential clinical application of osthol is limited due to its low water solubility and low bioavailability. Polybutyl cyanoacrylate (PBCA) has been widely used to improve the solubility of drugs with poor water solubility. In this study, an orthogonal experimental design (OED) was applied to design the preparation process of PBCA nanoparticles (NPs). Then, nanoparticles were prepared and evaluated in terms of physicochemical properties, in vitro release, and cellular uptake, etc. Further, the anti-cancer activity of osthol-PBCA NPs was demonstrated in SH-SY5Y cells. The pharmacokinetics and area under the curve (AUC) were investigated. The obtained osthol-NPs presented a spherical shape with a particle size of 110 ± 6.7 nm, a polydispersity index (PDI) of 0.126, and a zeta potential of −13 ± 0.32 mV. Compared with the free osthol, the drugs in osthol-NPs presented better stability and sustained release pattern activity. In vitro analysis using SH-SY5Y neuroblastoma cells showed that osthol-loaded nanoparticles displayed a significantly enhanced intracellular absorption process (three times) and cytotoxicity compared with free osthol (p < 0.05, increased 10−20%). The in vivo pharmacokinetic study revealed that the AUC of osthol-NPs was 3.3-fold higher than that of free osthol. In conclusion, osthol-PBCA NPs can enhance the bioactivity of osthol, being proposed as a novel, promising vehicle for drug delivery.

Design and Characterization of Paclitaxel-Loaded Polymeric Nanoparticles Decorated With Trastuzumab for the Effective Treatment of Breast Cancer

The aim of the study was to design and formulate an antibody-mediated targeted, biodegradable polymeric drug delivery system releasing drug in a controlled manner to achieve a therapeutic goal for the effective treatment of breast cancer. Antibody-mediated paclitaxel-loaded PLGA polymeric nanoformulations were prepared by the solvent evaporation method using different experimental parameters and compatibility studies. The optimized formulations were selected for in vitro and in vivo evaluation and cytotoxicity studies. The in vitro drug release studies show a biphasic release pattern for the paclitaxel-loaded PLGA nanoparticles showing a burst release for 24 h followed by an extended release for 14 days; however, a more controlled and sustained release was observed for antibody-conjugated polymeric nanoparticles. The cytotoxicity of reference drug and paclitaxel-loaded PLGA nanoparticles with and without antibody was determined by performing MTT assay against MCF-7 cells. Rabbits were used as experimental animals for the assessment of various in vivo pharmacokinetic parameters of selected formulations. The pharmacokinetic parameters such as C_max (1.18–1.33 folds), AUC_0-t (39.38–46.55 folds), MRT (10.04–12.79 folds), t_1/2 (3.06–4.6 folds), and V_d (6.96–8.38 folds) have been increased significantly while clearance (4.34–4.61 folds) has been decreased significantly for the selected nanoformulations as compared to commercially available paclitaxel formulation (Paclixil^®). The surface conjugation of nanoparticles with trastuzumab resulted in an increase in in vitro cytotoxicity as compared to plain nanoformulations and commercially available conventional brand (Paclixil^®). The developed PLGA-paclitaxel nanoformulations conjugated with trastuzumab have the desired physiochemical characteristics, surface morphology, sustained release kinetics, and enhanced targeting.

Co-encapsulation of vitamin D and rutin in chitosan-zein microparticles

There is a growing interest in co-encapsulating multiple species to harness potential synergy between them, enhance their stability and efficacy in various products. The aim of this work was to co-encapsulate vitamin D3 and rutin inside chitosan-zein microparticles using a simple and easily scalable process for food fortification. This was achieved via anti-solvent precipitation coupled with spray-drying. Free-flowing powders of spherical microparticles with wrinkled surface and particle size < 10 μm were obtained. The encapsulation efficiency was 75% for vitamin D3 and 44% for rutin and this could be attributed to their different molecular size and affinity to the aqueous phase. The physicochemical properties were characterized by X-Ray powder diffraction and Fourier transform infrared spectroscopy. The two crystalline bioactive compounds were present in the microparticles in amorphous form, which would allow for better bioavailability when compared to non-encapsulated crystalline solid. Therefore, the obtained microparticles would be suitable for use as food ingredient for vitamin D3 fortification, with the co-encapsulated rutin acting as stability and activity enhancer.

Role of non-coding RNAs in modulating the response of cancer cells to paclitaxel treatment

Paclitaxel is a chemotherapeutic substance that is administered for treatment of an extensive spectrum of human malignancies. In spite of its potent short-term effects against tumor cells, resistance to paclitaxel occurs in a number of patients precluding its long-term application in these patients. Non-coding RNAs have been shown to influence response of cancer cells to this chemotherapeutic agent via different mechanisms. Mechanistically, these transcripts regulate expression of several genes particularly those being involved in the apoptotic processes. Lots of in vivo and in vitro assays have demonstrated the efficacy of oligonucleotide-mediated microRNAs (miRNA)/ long non-coding RNAs (lncRNA) silencing in enhancement of response of cancer cells to paclitaxel. Therefore, targeted therapies against non-coding RNAs have been suggested as applicable modalities for combatting resistance to this agent. In the present review, we provide a summary of studies which assessed the role of miRNAs and lncRNAs in conferring resistance to paclitaxel.

Dopamine-loaded poly (butyl cyanoacrylate) nanoparticles reverse behavioral deficits in Parkinson’s animal models

Aim: Parkinson's disease (PD) is a neurological disorder resulting from decreased dopamine (DA) secretion in the brain, which reflects impaired motor function. Thus, a drug-delivery system for releasing DA into the brain would be of crucial importance. Materials & methods: We herein examined the in vivo drug efficiency of novel poly-butyl-cyanoacrylate nanoparticles loaded with DA (DA-PBCA NPs). Results & conclusion: The NPs were able to pass through the blood–brain barrier and improve brain structure and function in the PD animal models. Moreover, we found a reduced α-synucleinopathy in the animal model brains after the NPs administration. Thus, the NPs seem to be a reliable DA delivery system for treating PD patients.

Preparation, Characterization, and Evaluation of Cisplatin-Loaded Polybutylcyanoacrylate Nanoparticles with Improved In Vitro and In Vivo Anticancer Activities

This study aimed to evaluate the therapeutic efficacy of the cisplatin encapsulated into polybutylcyanoacrylate (PBCA) nanoparticles for the treatment of kidney cancer. The nanoformulation was successfully developed using the miniemulsion polymerization method and characterized in terms of size, size distribution, drug loading and encapsulation efficiencies, drug release behavior, in vitro cytotoxicity effects, in vivo toxicity, and therapeutic effects. Cisplatin-loaded PBCA nanoparticles were confirmed to be in nanoscale with the drug entrapment efficiency of 23% and controlled drug release profile, in which only 9% of the loaded drug was released after 48 h. The nanoparticles caused an increase in the cytotoxicity effects of cisplatin against renal cell adenocarcinoma cells (ACHN) (2.3-fold) and considerably decreased blood urea nitrogen and creatinine concentrations when compared to the standard cisplatin (1.6-fold and 1.5-fold, respectively). The nanoformulation also caused an increase in the therapeutic effects of cisplatin by 1.8-fold, in which a reduction in the mean tumor size was seen (3.5 mm vs. 6.5 mm) when compared to the standard cisplatin receiver rats. Overall, cisplatin-loaded PBCA nanoparticles can be considered as a promising drug candidate for the treatment of kidney cancer due to its potency to reduce the side effects of cisplatin and its toxicity and therapeutic effects on cancer-bearing Wistar rats.

Design of self-polymerized insulin loaded poly(n-butylcyanoacrylate) nanoparticles for tunable oral delivery

Macromolecular drugs, characterized by low stability and large molecular weight, still faced various difficulties by oral administration. And controlling drugs' release rate to reach the physiological concentration in the blood was recognized as one of the main challenges in this field but no studies are available so far. Thus, the objective of this study was to investigate the effect of insulin release rate on its in vitro and in vivo behavior when other obstacles (drug stability, mucus penetration and retention in gastrointestinal tract) was firstly overcome. Using n-butylcyanoacrylate (BCA) as the carrier, insulin-loaded Poly (n-butylcyanoacrylate) nanoparticles (Ins/PBCA NPs) were prepared by self-polymerization and the release rate of insulin was controlled by adjusting the mass ratio of Insulin/BCA. The NPs exhibited good stability in gastric fluid with controlled release in intestine and the release rate increased with the increase of Insulin/BCA mass ratio. All the Ins/PBCA NPs with different release rate showed excellent mucus penetration (>60%, 10 min) and strong gastrointestinal retention (~70%, 12 h). Especially, all the NPs showed promising hypoglycemic effect with the extent depending on drug release rate. Ins/BCA = 2/10 NPs exhibited fast hypoglycemic effect, while Ins/BCA = 2/15 NPs showed slow and outstanding performance. In conclusion, Ins/PBCA NPs could not only overcome the oral barriers of insulin delivery but also provide desired hypoglycemic effect by controlling insulin release rate.

Development and Characterization of Nanoliposomal Hydroxyurea Against BT-474 Breast Cancer Cells

Purpose: Hydroxyurea (HU) is a well-known chemotherapy drug with several side effects which limit its clinical application. This study was conducted to improve its therapeutic efficiency against breast cancer using liposomes as FDA-approved drug carriers.

Methods: PEGylated nanoliposomes-containing HU (NL-HU) were made via a thin-film hydration method, and assessed in terms of zeta potential, size, morphology, release, stability, cellular uptake, and cytotoxicity. The particle size and zeta potential of NL-HU were specified by zeta-sizer. The drug release from liposomes was assessed by dialysis diffusion method. Cellular uptake was evaluated by flow cytometry. The cytotoxicity was designated by methyl thiazolyl diphenyl-tetrazolium bromide (MTT) test.

Results: The size and zeta value of NL-HU were gotten as 85 nm and -27 mV, respectively. NL-HU were spherical.NL-HU vesicles were detected to be stable for two months. The slow drug release and Weibull kinetic model were obtained. Liposomes considerably enhanced the uptake of HU into BT-474 human breast cancer cells. The cytotoxicity of NL-HU on BT-474 cells was found to be significantly more than that of free HU.

Conclusion: The results confirmed these PEGylated nanoliposomes containing drug are potentially suitable against in vitro model of breast cancer.

Enhanced Efficacy of PEGylated Liposomal Cisplatin: In Vitro and In Vivo Evaluation

This study aims to evaluate the potency of cisplatin (Cispt)-loaded liposome (LCispt) and PEGylated liposome (PLCispt) as therapeutic nanoformulations in the treatment of bladder cancer (BC). Cispt was loaded into liposomes using reverse-phase evaporation method, and the formulations were characterized using dynamic light scattering, scanning electron microscopy, dialysis membrane, and Fourier-transform infrared spectroscopy (FTIR) methods. The results showed that the particles were formed in spherical monodispersed shapes with a nanoscale size (221–274 nm) and controlled drug release profile. The cytotoxicity effects of LCispt and PLCispt were assessed in an in vitro environment, and the results demonstrated that PLCispt caused a 2.4- and 1.9-fold increase in the cytotoxicity effects of Cispt after 24 and 48 h, respectively. The therapeutic and toxicity effects of the formulations were also assessed on BC-bearing rats. The results showed that PLCispt caused a 4.8-fold increase in the drug efficacy (tumor volume of 11 ± 0.5 and 2.3 ± 0.1 mm³ in Cispt and PLCispt receiver rats, respectively) and a 3.3-fold decrease in the toxicity effects of the drug (bodyweight gains of 3% and 10% in Cispt and PLCispt receiver rats, respectively). The results of toxicity were also confirmed by histopathological studies. Overall, this study suggests that the PEGylation of LCispt is a promising approach to achieve a nanoformulation with enhanced anticancer effects and reduced toxicity compared to Cispt for the treatment of BC.

Effects of phospholipid and polyethylene glycol monostearate (100) on the in vitro and in vivo physico-chemical characterization of poly(n-butyl cyanoacrylate) nanoparticles

In this study, poly(n-butyl cyanoacrylate) nanoparticles (PBCA-NPs) modified with various amounts of soybean phospholipid (PC) and polyethylene glycol monostearate (S100) were prepared in order to investigate the effects of PC and S100 on the nanoparticles' physico-chemical properties, cytological properties and in vivo gastrointestinal absorption. Coumarin-6 (C6) was used as a fluorescent probe; C6-loaded PBCA-NPs modified with both PC and S100 (C6-PS-PBCA-NPs) were prepared using miniemulsion polymerization, and C6-loaded PBCA-NPs modified with either S100 (C6-S-PBCA-NPs) or PC (C6-P-PBCA-NPs) were used as references. All of the different NPs were shown to be stably dispersed and to have a small particle size. A cytotoxicity study indicated that all of the blank PBCA-NPs were safe and nontoxic. The uptake of NPs by Caco-2 cells was shown to be increased when the amount of PC was increased from 0% to 1.25% and the amount of S100 was increased from 0% to 0.725%. The use of a ligated intestinal loop model demonstrated that C6-PS-PBCA-NPs could rapidly penetrate a highly viscoelastic mucous layer, leading to an improvement in the absorption efficiency. During a pharmacokinetic study, C6-PS-PBCA-NPs improved the absorption of C6, as indicated by their higher Cmax and AUC0-t values compared with those of C6-S-PBCA-NPs or C6-P-PBCA-NPs. Overall, the results of this study indicate that PBCA-NPs modified with PC and S100 can enhance the absorption of orally administered drugs.

Overcoming the Blood-Brain Barrier: The Role of Nanomaterials in Treating Neurological Diseases

Therapies directed toward the central nervous system remain difficult to translate into improved clinical outcomes. This is largely due to the blood-brain barrier (BBB), arguably the most tightly regulated interface in the human body, which routinely excludes most therapeutics. Advances in the engineering of nanomaterials and their application in biomedicine (i.e., nanomedicine) are enabling new strategies that have the potential to help improve our understanding and treatment of neurological diseases. Herein, the various mechanisms by which therapeutics can be delivered to the brain are examined and key challenges facing translation of this research from benchtop to bedside are highlighted. Following a contextual overview of the BBB anatomy and physiology in both healthy and diseased states, relevant therapeutic strategies for bypassing and crossing the BBB are discussed. The focus here is especially on nanomaterial-based drug delivery systems and the potential of these to overcome the biological challenges imposed by the BBB. Finally, disease-targeting strategies and clearance mechanisms are explored. The objective is to provide the diverse range of researchers active in the field (e.g., material scientists, chemists, engineers, neuroscientists, and clinicians) with an easily accessible guide to the key opportunities and challenges currently facing the nanomaterial-mediated treatment of neurological diseases.

In vitro and in vivo evaluation of 10-hydroxycamptothecin-loaded poly (n-butyl cyanoacrylate) nanoparticles prepared by miniemulsion polymerization

In this paper, 10-hydroxycamptothecin (HCPT)-loaded poly (n-butyl cyanoacrylate) nanoparticles (HCPT-PBCA-NPs) co-modified with polysorbate 80, soybean phospholipids, and polyethylene glycol (100) monostearate were successfully prepared via miniemulsion polymerization, and were characterized for particle size, morphology, zeta potential, encapsulation efficiency (EE) and drug loading capacity (DL). The chemical structure of HCPT-PBCA-NPs and the state of HCPT in the PBCA-NPs were investigated by DSC, FTIR and ¹H NMR. Additionally, drug release, cytotoxicity, cellular uptake capacity, cellular uptake mechanism, and in vivo behavior of NPs were investigated as well. The particles were 92.7nm in size with a high EE of 94.24%. FTIR, ¹H NMR, and DSC demonstrated complete polymerization of BCA monomers and the drug was in a molecular or amorphous form inside the NPs. In vitro release of the drug from HCPT-PBCA-NPs exhibited sustained-release and less than 60% of HCPT was released from the NPs within 24h of dialysis. Cellular uptake study displayed that Caco-2 cell uptake of NPs was governed by active endocytosis, clathrin- and caveolin-mediated process, and increased with the increase of the NPs concentration and the time. The pharmacokinetic study in rats showed that encapsulation of HCPT into PBCA-NPs increased the C_max and AUC_0-t about 6.52 and 7.56 times, respectively, in comparison with the HCPT suspension. It was concluded that HCPT loaded PBCA-NPs prepared by miniemulsion polymerization could be promising in oral drug delivery.

Controlled release of paclitaxel using a drug-eluting stent through modulation of the size of drug particles in vivo

Drug-eluting stents (DESs) are generally used in percutaneous coronary intervention. Paclitaxel (PTX) is widely used in DESs to suppress neointima, which causes restenosis. However, the PTX release profile is slow owing to its hydrophobic properties, resulting in negative effects on re-endothelialization in vessels. In this study, we assessed the effects of the controlled release of PTX particles of specific sizes on in-stent restenosis (ISR). PTX particle sizes were controlled by adjusting the evaporating temperature of the solvent from 25 to 80°C during ultrasonic coating, and DESs were prepared. The properties of prepared films and DESs were analyzed, and cell viability was assessed in vitro and in vivo. Poly(lactic-co-glycolic acid) (PLGA)/PTX500-loaded stents showed the most rapid release for 58 days, and smaller drug particles exhibited lower PTX release rates. In vivo, PLGA/PTX50-, PLGA/PTX250-, and PLGA/PTX500-loaded stents showed good efficacy for alleviating ISR as compared with bare metal stents and PLGA/PTX5-loaded stents. However, PLGA/PTX250- and PLGA/PTX500-loaded stents exhibited strut exposure and reduced recovery of the vascular compared with PLGA/PTX50-loaded stents. PTX drug particles of approximately 50 nm were most effective in vivo, and the control of particle size is a promising strategy for improving the performance of PTX-eluting stents. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2275-2283, 2018.

Method Validation for Progesterone Determination in Poly(methyl methacrylate) Nanoparticles Synthesized via Miniemulsion Polymerization

Exogenous progesterone has several applications in human health and in veterinary medicine, especially in fixed-time artificial insemination protocol. Progesterone nanoencapsulation in biocompatible polymers, such as poly(methyl methacrylate) (PMMA), is an alternative to substitute silicone-based release device traditionally used for estrus control. Progesterone concentration inside the nanoparticles must be precisely known; for that reason, a validation methodology must be applied to ensure reliable results, suitable for nanoparticles application. In this work, an UV-Vis spectrophotometric method was validated for the determination of progesterone in PMMA nanoparticles synthesized by miniemulsion polymerization. Chloroform was used as solvent, showing selectivity to the encapsulated drug and the components of the polymeric matrix did not influence progesterone recovery. Detection and quantitation limits (DL and QL) obtained were 0.32 and 0.96 mg·L−1, respectively, and precision tests (between different analysts and equipment) indicated acceptable Relative Standard Deviations (RSD < 5%). Miniemulsion polymerization reactions were carried out producing two different morphologies: nanospheres (NS) and nanocapsules (NC), with average intensity diameters (Dz) of 150–200 nm and 240–300 nm, respectively. Polymerization gravimetric conversions obtained for both cases were higher than 95% and encapsulation efficiencies greater than 69% and 90% for the nanospheres and nanocapsules, respectively.

Self-assembled nanoparticles based on amphiphilic chitosan derivative and arginine for oral curcumin delivery

Curcumin (Cur) is a striking anticancer agent, but its low aqueous solubility, poor absorption, hasty metabolism, and elimination limit its oral bioavailability and consequently hinder its development as a drug. To redress these limitations, amphiphilic chitosan (CS) conjugate with improved mucoadhesion and solubility over a wider pH range was developed by modification with hydrophobic acrylonitrile (AN) and hydrophilic arginine (Arg); the synthesized conjugate (AN–CS–Arg), which was well characterized by Fourier transform infrared and ¹H nuclear magnetic resonance spectroscopy. Results of critical aggregation concentration revealed that the AN–CS–Arg conjugate had low critical aggregation concentration and was prone to form self-assembled nanoparticles (NPs) in aqueous medium. Cur-encapsulated AN–CS–Arg NPs (AN–CS–Arg/Cur NPs) were developed by a simple sonication method and characterized for the physicochemical parameters such as zeta potential, particle size, and drug encapsulation. The results showed that zeta potential of the prepared NPs was 40.1±2.81 mV and the average size was ~218 nm. A considerable improvement in the aqueous solubility of Cur was observed after encapsulation into AN–CS–Arg/Cur NPs. With the increase in Cur concentration, loading efficiency increased but encapsulation efficiency decreased. The in vitro release profile exhibited sustained release pattern from the AN–CS–Arg/Cur NPs in typical biological buffers. The ex vivo mucoadhesion study revealed that AN–CS–Arg/Cur NPs had greater mucoadhesion than the control CS NPs. Compared with free Cur solution, AN–CS–Arg/Cur NPs showed stronger dose-dependent cytotoxicity against HT-29 cells. In addition, it was observed that cell uptake of AN–CS–Arg/Cur NPs was much higher compared with free Cur. Furthermore, the in vivo pharmacokinetic results in rats demonstrated that the AN–CS–Arg/Cur NPs could remarkably improve the oral bioavailability of Cur. Therefore, the developed AN–CS–Arg/Cur NPs might be a promising nano-candidate for oral delivery of Cur.

Combination chemotherapy of doxorubicin, all-trans retinoic acid and low molecular weight heparin based on self-assembled multi-functional polymeric nanoparticles

Based on the complementary effects of doxorubicin (DOX), all-trans retinoic acid (ATRA) and low molecular weight heparin (LMWH), the combination therapy of DOX, ATRA and LMWH was expected to exert the enhanced anti-tumor effects and reduce the side effects. In this study, amphiphilic LMWH-ATRA conjugate was synthesized for encapsulating the DOX. In this way, DOX, ATRA and LMWH were assembled into a single nano-system by both chemical and physical modes to obtain a novel anti-tumor targeting drug delivery system that can realize the simultaneous delivery of multiple drugs with different properties to the tumor. LMWH-ATRA nanoparticles exhibited good loading capacities for DOX with excellent physico-chemical properties, good biocompatibility, and good differentiation-inducing activity and antiangiogenic activity. The drug-loading capacity was up to 18.7% with an entrapment efficiency of 78.8%. It was also found that DOX-loaded LMWH-ATRA nanoparticles (DHR nanoparticles) could be efficiently taken up by tumor cells via endocytic pathway, and mainly distributed in cytoplasm at first, then transferred into cell nucleus. Cell viability assays suggested that DHR nanoparticles maintained the cytotoxicity effect of DOX on MCF-7 cells. Moreover, the in vivo imaging analysis indicated that DiR-loaded LMWH-ATRA nanoparticles could target the tumor more effectively as compared to free DiR. Furthermore, DHR nanoparticles possessed much higher anticancer activity and reduced side effects compared to free drugs solution. These results suggested that DHR nanoparticles could be considered as a promising targeted delivery system for combination cancer chemotherapy with lower adverse effects.

Core-shell structured gel-nanocarriers for sustained drug release and enhanced antitumor effect

The present paper attempted to develop temperature-sensitive and core-shell structured gel-nanocarriers (gel-NCs) for paclitaxel (PTX) with 12-hydroxystearic acid (12-HSA) as an organic gelator, which aims at sustaining drug release over time and thus improves the therapeutic effect. The gel-NCs were prepared by a mechanical mixing and high-pressure homogenization method. The gelation transition temperature (Tgel) of the organic phase contained in the cores of the gel-NCs was optimized by a stirring method. The gel-NCs were characterized in terms of the particle size, morphology and in vitro drug release. The in vivo studies, including the antitumor effects on H22 tumor-bearing mice, biocompatibility and toxicity in mice, were performed. Gel-NCs with approximately 170 nm were prepared successfully, and the gelation of the liquid cores at 37°C was achieved, while the amount of gelator was 3.75% (w/w). Due to the gelation of the cores, sustained drug release over time was obtained. Moreover, the PTX-loaded gel-NCs suppressed tumor growth more efficiently than the conventional nanocarriers with better in vivo biocompatibility and no toxicity to other healthy organs. In conclusion, the 12-HSA organogel-based NCs appear to be promising systems for the sustained release of active compounds for a long time and thus improve the therapeutic outcome.

PLGA biodegradable nanoparticles containing perphenazine or chlorpromazine hydrochloride: effect of formulation and release

In our study, poly(dl-lactide-co-glycolide) (PLGA) nanoparticles loaded with perphenazine (PPH) and chlorpromazine hydrochloride (CPZ-HCl) were formulated by emulsion solvent evaporation technique. The effect of various processing variables, including PLGA concentration, theoretical drug loading, poly(vinyl alcohol) (PVA) concentration and the power of sonication were assessed systematically to obtain higher encapsulation efficiency and to minimize the nanoparticles size. By the optimization formulation process, the nanoparticles were obtained in submicron size from 325.5 ± 32.4 to 374.3 ± 10.1 nm for nanoparticles loaded with PPH and CPZ-HCl, respectively. Nanoparticles observed by scanning electron microscopy (SEM) presented smooth surface and spherical shape. The encapsulation efficiency of nanoparticles loaded with PPH and CPZ-HCl were 83.9% and 71.0%, respectively. The drug loading were 51.1% and 39.4% for PPH and CPZ-HCl, respectively. Lyophilized nanoparticles with different PLGA concentration 0.8%, 1.3% and 1.6% (w/v) in formulation process were evaluated for in vitro release in phosphate buffered saline (pH = 7.4) by using dialysis bags. The release profile for both drugs have shown that the rate of PPH and CPZ-HCl release were dependent on a size and amount of drugs in the nanoparticles.

Preparation and Characterization of Starch Nanoparticles for Controlled Release of Curcumin

Curcumin was loaded onto starch nanoparticles by usingin situnanoprecipitation method and water-in-oil microemulsion system. Curcumin loaded starch nanoparticles exhibited enhanced solubility in aqueous solution as compared to free curcumin. Effects of formulation parameters such as types of reaction medium, types of surfactant, surfactant concentrations, oil/ethanol ratios, loading time, and initial curcumin concentration were found to affect the particle size and loading efficiency (LF) of the curcumin loaded starch nanoparticles. Under optimum conditions, curcumin loaded starch nanoparticles with mean particles size of 87 nm and maximum loading efficiency of 78% were achieved. Curcumin was observed to release out from starch nanoparticles in a sustained way under physiological pH over a period of 10 days.

Thermal and pH Sensitive Multifunctional Polymer Nanoparticles for Cancer Imaging and Therapy

In this study, we prepared novel poly(Glycerol malate co-dodecanedioate) (PGMD) NPs containing an imaging/hyperthermia agent (IR820) and a chemotherapeutic agent (doxorubicin, DOX). The PGMD polymer was prepared by thermal condensation. IR820 and DOX loaded PGMD NPs were prepared using the single oil emulsion technique. The size of the NPs measured was around 150 nm. Drug loading efficiency of DOX and IR820 was around 4% and 8%, respectively. An acidic environment (pH=5.0) induced higher DOX release as compared to pH=7.4. DOX release was also enhanced by exposure to laser, which increased the temperature to 42°C. Cytotoxicity of the drug loaded NPs was comparable in MES-SA but was higher in Dx5 cells compared to free drug (p<0.05). The combination of hyperthermia and chemotherapy improved cytotoxicity in both cell lines. The NP formulation significantly improved the plasma half-life of IR820 in mice after tail vein injection.

Paclitaxel Nano-Delivery Systems: A Comprehensive Review

Paclitaxel is one of the most effective chemotherapeutic drugs ever developed and is active against a broad range of cancers, such as lung, ovarian, and breast cancers. Due to its low water solubility, paclitaxel is formulated in a mixture of Cremophor EL and dehydrated ethanol (50:50, v/v) a combination known as Taxol. However, Taxol has some severe side effects related to Cremophor EL and ethanol. Therefore, there is an urgent need for the development of alternative Taxol formulations. The encapsulation of paclitaxel in biodegradable and non-toxic nano-delivery systems can protect the drug from degradation during circulation and in-turn protect the body from toxic side effects of the drug thereby lowering its toxicity, increasing its circulation half-life, exhibiting improved pharmacokinetic profiles, and demonstrating better patient compliance. Also, nanoparticle-based delivery systems can take advantage of the enhanced permeability and retention (EPR) effect for passive tumor targeting, therefore, they are promising carriers to improve the therapeutic index and decrease the side effects of paclitaxel. To date, paclitaxel albumin-bound nanoparticles (Abraxane®) have been approved by the FDA for the treatment of metastatic breast cancer and non-small cell lung cancer (NSCLC). In addition, there are a number of novel paclitaxel nanoparticle formulations in clinical trials. In this comprehensive review, several types of developed paclitaxel nano-delivery systems will be covered and discussed, such as polymeric nanoparticles, lipid-based formulations, polymer conjugates, inorganic nanoparticles, carbon nanotubes, nanocrystals, and cyclodextrin nanoparticles.