Combined hydroxypropyl-β-cyclodextrin and poly(anhydride) nanoparticles improve the oral permeability of paclitaxel

Cyclodextrin Nanosponges: A Revolutionary Drug Delivery Strategy

Nanosponges are porous solid cross-linked polymeric nanostructures. This study focuses on cyclodextrin-based nanosponges. Nanosponges based on cyclodextrin can form interactions with various lipophilic or hydrophilic compounds. The release of the entrapped molecules can be altered by altering the structure to obtain either a longer or faster release kinetics. The nanosponges might increase the aqueous solubility of weakly water-soluble compounds, develop long-lasting delivery systems, or construct novel drug carriers for nanomedicine. CD-NS (cyclodextrin-based nanosponges) are evolving as flexible and promising nanomaterials for medication administration, sensing, and environmental cleanup. CD-NS are three-dimensional porous structures of cyclodextrin molecules cross-linked by a suitable polymeric network, resulting in a large surface area. This overview covers CD-NS synthesis methods and applications.

Colon targeted releases and uptakes of paclitaxel loaded in modified porous starch

Hyaluronic acid can modify porous starch through cross-linking and hydrogen bonding, effectively achieving a paclitaxel entrapment efficiency of ∼92 % and drug loading of ∼23 %. In this study, the pores and intergranular gaps of porous starch were filled with paclitaxel under solvent volatilization, and the enrichment process and its characteristics were recorded using a microscope. The paclitaxel-loaded particles were coated with chitosan-phytic acid to target the colon. In vivo imaging in mice showed that the capsule released paclitaxel in the colon rather than in the upper digestive tract, and the paclitaxel distribution in the main organs at 24 h was significantly lower than that of raw paclitaxel. Hyaluronic acid-modified porous starch can target cancer cells. Cell internalization of paclitaxel mediated by hyaluronic acid was approximately 1.97 times that of raw paclitaxel, higher than that of receptor-shielded cells and cells incubated with unmodified carriers, as evidenced by the accumulation of fluorescent paclitaxel in the nucleus and marked cell apoptosis. The hyaluronic acid-modified porous starch system is an effective method for the high-load and targeted release of hydrophobic anticancer drugs.

Review of the Role of Nanotechnology in Overcoming the Challenges Faced in Oral Cancer Diagnosis and Treatment

Throughout the world, oral cancer is a common and aggressive malignancy with a high risk of morbidity, mortality, and recurrence. The importance of early detection in cancer prevention and disease treatment cannot be overstated. Conventional therapeutic strategies have minor difficulties but considerable side effects and unfavourable consequences in clinical applications. Hence, there is a requirement for effective ways for early detection and treatment of oral cancer. At present, numerous forms of nanoparticles have piqued researchers' interest as a potentially useful tool for diagnostic probes and medicinal devices. Because of their inherent physicochemical properties and customizable surface modification, they are able to circumvent some of restrictions and accomplish the intended diagnostic and therapeutic impact. Nanotechnology is a unique field that has revolutionised the industry and is paving the way for new treatments for oral cancer. It can help with a better diagnosis with less harmful substances and is setting current guidelines for treatment. The use of nanotechnology in cancer diagnosis, therapy, and care improves clinical practise dramatically. The different types of nanoparticles that have been developed for the diagnosis and therapy of oral cancers will be covered in this study. The difficulties and potential uses of nanoparticles in the treatment and diagnosis of oral cancer are then highlighted. In order to emphasise existing difficulties and potential remedies for oral cancer, a prospective view of the future is also provided.

Polyanhydride Chemistry

Polyanhydrides (PAs) are a class of synthetic biodegradable polymers employed as controlled drug delivery vehicles. They can be synthesized and scaled up from low-cost starting materials. The structure of PAs can be manipulated synthetically to meet desirable characteristics. PAs are biocompatible, biodegradable, and generate nontoxic metabolites upon degradation, which are easily eliminated from the body. The rate of water penetrating into the polyanhydride (PA) matrix is slower than the anhydride bond cleavage. This phenomenon sets PAs as "surface-eroding drug delivery carriers." Consequently, a variety of PA-based drug delivery carriers in the form of solid implants, pasty injectable formulations, microspheres, nanoparticles, etc. have been developed for the sustained release of small molecule drugs, and vaccines, peptide drugs, and nucleic acid-based active agents. The rate of drug delivery is often controlled by the polymer erosion rate, which is influenced by the polymer structure and composition, crystallinity, hydrophobicity, pH of the release medium, device size, configuration, etc. Owing to the above-mentioned interesting physicochemical and mechanical properties of PAs, the present review focuses on the advancements made in the domain of synthetic biodegradable biomedical PAs for therapeutic delivery applications. Various classes of PAs, their structures, their unique characteristics, their physicochemical and mechanical properties, and factors influencing surface erosion are discussed in detail. The review also summarizes various methods involved in the synthesis of PAs and their utility in the biomedical domain as drug, vaccine, and peptide delivery carriers in different formulations are reviewed.

Developments on the Smart Hydrogel-Based Drug Delivery System for Oral Tumor Therapy

At present, an oral tumor is usually treated by surgery combined with preoperative or postoperative radiotherapies and chemotherapies. However, traditional chemotherapies frequently result in substantial toxic side effects, including bone marrow suppression, malfunction of the liver and kidneys, and neurotoxicity. As a new local drug delivery system, the smart drug delivery system based on hydrogel can control drug release in time and space, and effectively alleviate or avoid these problems. Environmentally responsive hydrogels for smart drug delivery could be triggered by temperature, photoelectricity, enzyme, and pH. An overview of the most recent research on smart hydrogels and their controlled-release drug delivery systems for the treatment of oral cancer is given in this review. It is anticipated that the local drug release method and environment-responsive benefits of smart hydrogels will offer a novel technique for the low-toxicity and highly effective treatment of oral malignancy.

Development of Cyclodextrin-Functionalized Transethoniosomes of 6-Gingerol: Statistical Optimization, In Vitro Characterization and Assessment of Cytotoxic and Anti-Inflammatory Effects

The poor solubility and stability of 6-gingerol (6-G) could hamper its clinical applications. The aim of the current study was to develop a novel ultra-deformable cyclodextrin-functionalized transethoniosomes (CD-TENs) as a promising delivery system for 6-G. Transethoniosomes (TENs) are flexible niosomes (NVs) due to their content of ethanol and edge activators (EAs). CD-functionalized nanoparticles could improve drug solubility and stability compared to the corresponding nanovesicles. 6-G-loaded ethoniosomes (ENs) were formulated by the ethanol injection technique in the presence and absence of EA and CD to explore the impact of the studied independent variables on entrapment efficiency (EE%) and % 6-G released after 24 h (Q_24h). According to the desirability criteria, F8 (CD-functionalized transethoniosomal formula) was selected as the optimized formulation. F8 demonstrated higher EE%, permeation, deformability and stability than the corresponding TENs, ENs and NVs. Additionally, F8 showed higher cytotoxic and anti-inflammatory activity than pure 6-G. The synergism between complexation with CD and novel ultra-deformable nanovesicles (TENs) in the form of CD-TENs can be a promising drug delivery carrier for 6-G.

Models using native tracheobronchial mucus in the context of pulmonary drug delivery research: Composition, structure and barrier properties

Mucus covers all wet epithelia and acts as a protective barrier. In the airways of the lungs, the viscoelastic mucus meshwork entraps and clears inhaled materials and efficiently removes them by mucociliary escalation. In addition to physical and chemical interaction mechanisms, the role of macromolecular glycoproteins (mucins) and antimicrobial constituents in innate immune defense are receiving increasing attention. Collectively, mucus displays a major barrier for inhaled aerosols, also including therapeutics. This review discusses the origin and composition of tracheobronchial mucus in relation to its (barrier) function, as well as some pathophysiological changes in the context of pulmonary diseases. Mucus models that contemplate key features such as elastic-dominant rheology, composition, filtering mechanisms and microbial interactions are critically reviewed in the context of health and disease considering different collection methods of native human pulmonary mucus. Finally, the prerequisites towards a standardization of mucus models in a regulatory context and their role in drug delivery research are addressed.

Biodegradable and biocompatible polymeric nanoparticles for enhanced solubility and safe oral delivery of docetaxel: In vivo toxicity evaluation

Docetaxel (DTX) is a chemotherapeutic drug with poor hydrophilicity and permeability. Its lipophilic properties decrease its absorption in systemic circulation which hinders its therapeutic efficacy & safety. Cyclodextrins (CDs) with their unique structural properties enhance solubility of chemotherapeutic drugs. The study was designed to formulate docetaxel-cyclodextrins inclusion complexes for enhancement of solubility with sulfobutyl ether β-cyclodextrin (SBE₇-β-CD), hydroxypropyl β-cyclodextrin (HP-β-CD) and β-cyclodextrin (β-CD). Further, by using ionic gelation method polymeric nanoparticles of docetaxel-cyclodextrins were prepared with sodium tri poly phosphate (STPP) and chitosan (CS). Optimization is performed by varying CS and STPP mass ratios. Nanoparticles were analyzed for their physicochemical properties, drug-excipient compatibility, thermal stability and oral toxicity. CDs enhanced the solubility of DTX. Nanoparticles were found within 144.8 ± 65.19 - 372.0 ± 126.9 nm diameters with polydispersity ranging 0.117-0.375. The particles were found round & circular in shape with smooth and non-porous surface. Increased quantity of drug release was observed from DTX-CDs loaded nanoparticles than pure drug loaded nanoparticles. Oral toxicity in rabbits revealed biochemical, histopathological profile with no toxic effect on cellular structure of animals.

Research Progress and Prospect of Nanoplatforms for Treatment of Oral Cancer

Oral cancers refer to malignant tumors associated with high morbidity and mortality, and oral squamous cell carcinoma accounts for the majority of cases. It is an important part of head and neck, and oral cancer is one of the six most common cancers in the world. At present, the traditional treatment methods for oral cancer include surgery, radiation therapy, and chemotherapy. However, these methods have many disadvantages. In recent years, nanomedicine, the delivery of drugs through nanoplatforms for the treatment of cancer, has become a promising substitutive therapy. The use of nanoplatforms can reduce the degradation of the drug in the body and accurately deliver it to the tumor site. This minimizes the distribution of the drug to other organs, thereby reducing its toxicity and allowing higher drug concentration at the tumor site. This review introduces polymer nanoparticles, lipid-based nanoparticles, metal nanoparticles, hydrogels, exosomes, and dendrimers for the treatment of oral cancer, and discusses how these nanoplatforms play an anti-cancer effect. Finally, the review gives a slight outlook on the future prospects of nanoplatforms for oral cancer treatment.

Current Trends of Targeted Drug Delivery for Oral Cancer Therapy

Oral cancer is an aggressive tumor that invades the local tissue and can cause metastasis and high mortality. Conventional treatment strategies, e.g., surgery, chemotherapy, and radiation therapy alone or in combinations, possess innegligible issues, and significant side and adverse effects for the clinical applications. Currently, targeting drug delivery is emerging as an effective approach for oral delivery of different therapeutics. Herein we provide a state-of-the-art review on the current progress of targeting drug delivery for oral cancer therapy. Variously oral delivery systems including polymeric/inorganic nanoparticles, liposomes, cyclodextrins, nanolipids, and hydrogels-based forms are emphasized and discussed, and biomimetic systems with respect to oral delivery like therapeutic vitamin, exosomes, proteins, and virus-like particles are also described with emphasis on the cancer treatment. A future perspective is also provided to highlight the existing challenges and possible resolution toward clinical translation of current oral cancer therapies.

Docetaxel-Loaded Poly(3HB-co-4HB) Biodegradable Nanoparticles: Impact of Copolymer Composition

Polyhydroxyalkanoate (PHA) copolymers show a relatively higher in vivo degradation rate compared to other PHAs, thus, they receive a great deal of attention for a wide range of medical applications. Nanoparticles (NPs) loaded with poorly water-soluble anticancer drug docetaxel (DCX) were produced using poly(3-hydroxybutyrate-co-4-hydroxybutyrate), P(3HB-co-4HB), copolymers biosynthesised from Cupriavidus malaysiensis USMAA1020 isolated from the Malaysian environment. Three copolymers with different molar proportions of 4-hydroxybutirate (4HB) were used: 16% (PHB16), 30% (PHB30) and 70% (PHB70) 4HB-containing P(3HB-co-4HB). Blank and DCX-loaded nanoparticles were then characterized for their size and size distribution, surface charge, encapsulation efficiency and drug release. Preformulation studies showed that an optimised formulation could be achieved through the emulsification/solvent evaporation method using PHB70 with the addition of 1.0% PVA, as stabilizer and 0.03% VitE-TPGS, as surfactant. DCX-loaded PHB70 nanoparticles (DCX-PHB70) gave the desired particle size distribution in terms of average particle size around 150 nm and narrow particle size distribution (polydispersity index (PDI) below 0.100). The encapsulation efficiency result showed that at 30% w/w drug-to-polymer ratio: DCX- PHB16 NPs were able to encapsulate up to 42% of DCX; DCX-PHB30 NPs encapsulated up to 46% of DCX and DCX-PHB70 NPs encapsulated up to 50% of DCX within the nanoparticle system. Approximately 60% of DCX was released from the DCX-PHB70 NPs within 7 days for 5%, 10% and 20% of drug-to-polymer ratio while for the 30% and 40% drug-to-polymer ratios, an almost complete drug release (98%) after 7 days of incubation was observed.

Nanotechnology-based drug delivery systems for enhanced diagnosis and therapy of oral cancer

Oral cancer is a common malignant life-threatening tumor. Despite some advances in traditional therapy, mortality and mobidity rates are high due to delayed diagnosis and ineffective treatment. Additionally, some patients inevitably suffer from various fatal adverse effects during the course of therapy. Therefore, it is imperative to develop novel methods to eradicate oral cancer cells with minimal adverse effects on normal cells. Nanotechnology is a promising and novel vehicle for the diagnosis and treatment of oral cancer with encouraging recent achievements. In this review, we present state-of-the-art nanotechnology-based drug delivery systems employed in the domain of oral cancer, especially for its enhanced diagnosis and therapy. We describe in detail the types of nanotechnology used in the management of oral cancer and summarize administration routes of nanodrugs. Finally, the potential and prospects of nanotechnology-based drug delivery systems as promising modalities of diagnosis and therapy of oral cancer are highlighted.

Enhanced absorption, and efficacy of oral self-assembled paclitaxel nanocochleates in multi-drug resistant colon cancer

Chemotherapy in drug-resistant cancers remains a challenge. Owing to associated poor bioavailability, oral administration of hydrophobic anticancer drugs like paclitaxel has been quite challenging, with the scenario being further complicated by Pgp efflux in drug-resistant tumours. We developed a novel nanocochleates (CPT) system encapsulating paclitaxel (PTX) to treat resistant colon cancer by oral administration. PTX encapsulated nanocochleates (PTX-CPT), made up of phosphatidylserine in size range of 350-600 nm with -20 ± 5.2 mV zeta potential were protected from degradation at acidic gastric pH and showed sustained PTX release over 48 h under intestinal pH condition. In vitro cytotoxicity studies on HCT-116 & HCT-15 cells (multi-drug resistant) established IC50 value of <10 and 69 nM, respectively, which was significantly lower when compared to commercial Taxol formulation. Further, the in vivo efficacy with five oral doses of 30 mg/kg PTX-CPT in an HCT-15 drug-resistant colon cancer xenograft mouse model showed more than 25 fold reduction in the tumour growth inhibition as compared to intravenous Taxol which showed just 1.94% inhibition. Interestingly, PTX-CPT treated mice also showed significantly lower proliferation index and microvessel density when compared to Taxol treated mice. Nanocochleates showed lower toxicity with at LD-50 value greater than 300 mg/kg as described in OECD 423 guideline. The enhanced efficacy of PTX-CPT speculated due to its internalization by active endocytosis, ability to escape Pgp efflux, and due to a combined effect of the pro-apoptotic and antiangiogenic role. Taken together, the results suggested the PTX-CPT a promising strategy for efficiently treating drug-resistant colon cancer orally.

Oral Delivery of Anticancer Agents Using Nanoparticulate Drug Delivery System

Background:

Conventionally, anti-cancer agents were administered through the intravenous route. The major drawbacks associated with the intravenous route of administration are: severe side effects, need of hospitalization, nursing care, and palliative treatment. In order to overcome the drawbacks associated with the intravenous route of administration, oral delivery of anti-cancer agents has gained tremendous interest among the scientific fraternity. Oral delivery of anti-cancer agents principally leads to a reduction in the overall cost of treatment, and aids in improving the quality of life of patients. Bioavailability of drugs and inter-subject variability are the major concerns with oral administration of anti-cancer agents. Factors viz. physicochemical and biological barriers (pre-systemic metabolism and transmembrane efflux of the drug) are accountable for hampering oral bioavailability of anti-cancer agents can be efficiently overcome by employing nanocarrier based drug delivery systems. Oral delivery of anticancer agents by employing these drug delivery systems will not only improve the quality of life of patients but will also provide pharmacoeconomic advantage and lead to a reduction in the overall cost of treatment of life-threatening disease like cancer.

Objective:

This article aims to familiarize the readers with some of the recent advancements in the field of nanobased drug delivery systems for oral delivery of anticancer agents.

Conclusion:

Advancement in the field of nanotechnology-based drug delivery systems has opened up gateways for the delivery of drugs that are difficult to administer orally. Oral delivery of anti-cancer agents by these drug delivery systems will not only improve the quality of life of patients but will also provide pharmacoeconomic advantage and lead to a reduction in the overall cost of treatment of life-threatening disease like cancer.

Cyclodextrin Based Nanoparticles for Drug Delivery and Theranostics

Colloidal nanoparticulate technology has been described in the literature as a versatile drug delivery system. But it possesses some inherent lacunae in their formulation. Cyclodextrins (CDs) have been extensively reported for the solubility enhancement of poorly water-soluble drugs. The CDs can cause intervention in aspects related to nanoparticles (NPs) that include improving drug loading in nano-system, improving stability, site-specific/targeted drug delivery, improving solubility profile and absorption of the drug in nanosystem with consequent improvement in bioavailability, with the possibility of controlled release, safety and efficacy. They find application in for simultaneous diagnosis and therapeutics for better treatment procedures. The current communication is focused on the application of CDs to overcome troubles in nanoparticulate formulation and enhancement of their performance. It also envisages the theranostic aspects of CDs.

Oral and Intra-nasal Administration of Nanoparticles in the Cerebral Ischemia Treatment in Animal Experiments: Considering its Advantages and Disadvantages

BACKGROUND

Over the past few decades, nanotechnology has dramatically advanced; from the precise strategies of synthesizing modern nanostructures to methods of entry into the body. Using nanotechnology in diagnosis, drug delivery, determining signaling pathways, and tissue engineering is great hope for the treatment of stroke. The drug-carrying nanoparticles are a way to increase drug absorption through the mouth or nose in treating the stroke.

OBJECTIVE

In this article, in addition to explaining pros and cons of oral and intra-nasal administration of nanoparticles in the brain ischemia treatment of animal models, the researchers introduce some articles in this field and briefly mentioned their work outcomes.

METHODS

A number of relevant published articles 183 were initially collected from three popular databases including PubMed, Google Scholar, and Scopus. The articles not closely related to the main purpose of the present work were removed from the study process. The present data set finally included 125 published articles.

RESULTS

Direct delivery of the drug to the animal brain through the mouth and nose has more therapeutic effects than systemic delivery of drugs. The strategy of adding drugs to the nanoparticles complex can potentially improve the direct delivery of drugs to the CNS.

CONCLUSION

Despite the limitations of oral and intra-nasal routes, the therapeutic potential of oral and intra-nasal administration of nano-medicines is high in cerebral ischemia treatment.

Synthesis and in vitro evaluation of cyclodextrin hyaluronic acid conjugates as a new candidate for intestinal drug carrier for steroid hormones

Steroid hormones became increasingly interesting as active pharmaceutical ingredients for the treatment of endocrine disorders. However, medical applications of many steroidal drugs are inhibited by their very low aqueous solubilities giving rise to low bioavailabilities. Therefore, the prioritized oral administration of steroidal drugs remains problematic. Cyclodextrins are promising candidates for the development of drug delivery systems for oral route applications, since they solubilize hydrophobic steroids and increase their rate of transport in aqueous environments. In this study, the synthesis and characterization of polymeric β-cyclodextrin derivates is described, which result from the attachment of a hydrophilic β-CD-thioether to hyaluronic acid. Host-guest complexes of the synthesized β-cyclodextrin hyaluronic acid conjugates were formed with two poorly soluble model steroids (β-estradiol, dexamethasone) and compared to monomeric β-cyclodextrin derivates regarding solubilization and complexation efficiency. The β-cyclodextrin-drug (host-guest) complexes were evaluated in vitro for their suitability (cytotoxicity and transport rate) as intestinal drug carriers for steroid hormones. In case of β-estradiol, higher solubilities could be achieved by complexation with both synthesized β-cyclodextrin derivates, leading to significantly higher intestinal transport rates in vitro. However, this success could not be shown for dexamethasone, which namely solubilized better, but could not enhance the transport rate significantly. Thus, this study demonstrates the biocompatibility of the synthesized and characterized β-cyclodextrin derivates and shows their potential as new candidate for intestinal drug carrier for steroid hormones like β-estradiol.

Preparation of Deoxycholate-Modified Docetaxel-Cimetidine Complex Chitosan Nanoparticles to Improve Oral Bioavailability

Docetaxel (DTX) was effective in the treatment of neoplasm but could only be administered intravenously with the poor oral bioavailability owing to its undesirable solubility, remarkably metabolic conversion, and other factors. Cimetidine (CMD), a classic CYP3A4 isozyme inhibitor, had exhibited a wide range of inhibition on the metabolism of many drugs. The aim of this study was to construct the novel docetaxel-cimetidine (DTX-CMD) complex and the chitosan-deoxycholate nanoparticles based on it to confirm whether this formulation could show advantages in terms of solubility, dissolution rate, small intestinal absorption, and oral bioavailability in comparison with the pure drug. The solid-state characterization was carried out by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), and simultaneous DSC-TGA (SDT). Dissolution rate and kinetic solubility study were determined by evaluating the amount of DTX in distilled water and phosphate buffer solution (pH = 7.4), respectively. And small intestinal absorption and pharmacokinetics study were conducted in rats. The results of this study demonstrated that we successfully constructed DTX-CMD complex and its chitosan-deoxycholate nanoparticles. Furthermore, the DTX-CMD complex increased the solubility of DTX by 2.3-fold and 2.1-fold in distilled water and phosphate buffer solution, respectively. The ultimate accumulative amount of DTX-CMD complex nanoparticles through rat small intestinal in 2 h was approximately 4.9-fold and the oral bioavailability of the novel nanoparticles was enhanced 2.8-fold, compared with the pure DTX. The superior properties of the complex nanoparticles could both improve oral bioavailability and provide much more feasibility for other formulations of DTX.

Mechanical characterization and ex vivo evaluation of anticancer and antiviral drug printed bioadhesive film for the treatment of cervical cancer

As research progresses on personalized medicines, it is clear that personalized and flexible formulations can provide effective treatment with reduced side effects especially for diseases like cancer, characteristic of high patient variability. 2D and 3D printers are frequently reported in the literature for the preparation of pharmaceutical products with adjusted dose and selected drug combinations. However, in-depth characterization studies of these formulations are rather limited. In this paper, ex vivo and mechanical characterization studies of antiviral and anticancer drug printed film formulations designed for personalized application were performed. Effects of the printing process with pharmaceutical formulations such as paclitaxel (PCX):cyclodextrin (CD) complex or cidofovir (CDV) encapsulated into poly(ethylene glycol)-polycaprolactone (PEG-PCL) nanoparticles on the films were evaluated through a series of mechanical characterization studies. Inkjet printing process was found to cause no significant change in the thicknesses of the film formulations, while mechanical strength and surface free energy increased and nano-sized voids in the film structure decreased. According to the mechanical characterization data, the unprinted film had maximum force (F_max) value of 15.6 MPa whereas F_max increased to 43.8 MPa for PCX:CD complex printed film and to 37.7 MPa for the antiviral CDV-PEG-PCL nanoparticle printed film. In the light of ex vivo findings of sheep cervix-uterine tissue, bioadhesive properties of film formulations significantly improved after inkjet printing with different drug formulations. It has also been shown that the anticancer formulation printed on the film was maintained at the cervix tissue surface for >12 h. This study has shown for the first time that inkjet printing process does not adversely affect the mechanical properties of the bioadhesive film formulations. It has also been shown that durable bioadhesive film formulations for personalized dosing can be prepared by combining nanotechnology and inkjet printing.

Microfluidic-assisted nanoprecipitation of (PEGylated) poly (d,l-lactic acid-co-caprolactone): Effect of macromolecular and microfluidic parameters on particle size and paclitaxel encapsulation

In this work we evaluate the effect of polymer composition and architecture of (PEGylated) polyesters on particle size and paclitaxel (PTX) loading for particles manufactured via microfluidic-assisted, continuous-flow nanoprecipitation using two microfluidic chips with different geometries and mixing principles. We have prepared poly (d,l-lactic acid-co-caprolactone) (PLCL) from ring-opening polymerization (ROP) of LA and CL mixtures and different (macro) initiators (namely, 1-dodecanol, a MeO-PEG-OH, and a 4-armed star PEG-OH), rendering polyesters that vary in monomer composition (i.e. LA/CL ratios) and architecture (i.e. linear vs 4-armed star). Continuous-flow nanoprecipitation was assayed using two microfluidic chips: a cross-flow chip with a X-shaped mixing junction (2D laminar flow focusing) and a micromixer featuring a Y-shaped mixing junction and a split and recombine path (2D laminar flow focusing convinced with stream lamination for faster mixing). Nanoparticle formulations were produced with Z-average sizes in the range of 30-160 nm, although size selectivity could be seen for different polymer/chip combinations; for instance, smaller particles were obtained with Y-shaped micromixer (30-120 nm), specially for the PEGylated polyesters (30-50 nm), whereas the cross-flow chip systematically produced larger particles (80-160 nm). Loading of the anti-cancer drug paclitaxel (PTX) was also heavily influenced not only by the nature of the polyester, but also by the geometry of the microfluidic chip; higher drug loadings were obtained with the cross-flow reactor and the star block copolymers. Finally, decreasing the LA/CL ratio generally had a positive effect on drug loading.

Cyclodextrin-grafted poly(anhydride) nanoparticles for oral glibenclamide administration. In vivo evaluation using C. elegans

The aim of this work was to prepare and evaluate cyclodextrins-modified poly(anhydride) nanoparticles to enhance the oral administration of glibenclamide. A conjugate polymer was synthesized by incorporating hydroxypropyl-β-cyclodextrin to the backbone of poly(methylvinyl ether-co-maleic anhydride) via Steglich reaction. The degree of substitution of anhydride rings by cyclodextrins molecules was calculated to be 4.9% using H-NMR spectroscopy. A central composite design of experiments was used to optimize the preparative process. Under the optimal conditions, nanoparticles displayed a size of about 170 nm, a surface charge of -47 mV and a drug loading of 69 µg GB/mg. X-ray diffraction studies confirmed the loss of the crystalline structure of GB due to its dispersion into the nanoparticles, either included into cyclodextrin cavities or entrapped in the polymer chains. Glibenclamide was mainly release by Fickian-diffusion in simulated intestinal fluid. GB-loaded nanoparticles produced a hypolipidemic effect over C. elegans N2 wild-type and daf-2 mutant. The action mechanism included daf-2 and daf-28 genes, both implicated in the insulin signaling pathway of C. elegans. In summary, the covalent linkage of cyclodextrin to the poly(anhydride) backbone could be an interesting strategy to prepare nanoparticles for the oral administration of glibenclamide.

Hydrogels based on poly(methyl vinyl ether-co-maleic acid) and Tween 85 for sustained delivery of hydrophobic drugs

Hydrogels based on poly(methyl vinyl ether-co-maleic acid) and Tween 85 were prepared for hydrophobic drug delivery. The hydrogels were synthesized following a simple procedure carried out in solid state. The process did not require the use of any solvent and, as it is based on an esterification reaction, no toxic by-products were obtained. The resulting hydrogels contained Tween 85 inside the structure and due to the amphiphilic nature of this compound, hydrophobic domains within the hydrogel structure were formed. The obtained hydrogels showed good swelling capacities ranging from 100% to 600%. The esterification reaction that took place between poly(methyl vinyl ether-co-maleic acid) and Tween 85 was confirmed by infrared spectroscopy. Hydrogels were loaded with a hydrophobic drug model, Curcumin (CUR), showing that the hydrogels were able to retain up to 36 mg of CUR per g of hydrogel. Additionally, the synthesized hydrogels provided in vitro sustained CUR release over periods of up to 30 days. Finally, and due to the mucoadhesive nature of the prepared materials, one of the hydrogels was tested in vitro as an oral drug delivery system. For this purpose, the selected material was milled into microparticles (45-90 µm diameter). The release of CUR from the microparticles was evaluated under simulated gastric and intestinal conditions. The microparticles were able to release their cargos in 7 h. However, further work is required to optimize this system for oral drug delivery applications.

Coencapsulation of cyclodextrins into poly(anhydride) nanoparticles to improve the oral administration of glibenclamide. A screening on C. elegans

This work describes the feasibility of poly(anhydride) nanoparticles as carriers for the oral administration of glibenclamide (GB) as well as the in vivo evaluation of their hypolipidemic effect in a C. elegans model. For this purpose, and in order to increase the GB payload, the drug was encapsulated in nanoparticles in presence of cyclodextrins (either βCD or HPβCD). The optimized nanoparticles displayed a size of about 220 nm and a negative zeta potential (-40 mV), with a drug loading up to 52 μg/mg. Small-angle neutron scattering studies suggested an internal fractal-like structure, based on the repetition of spherical blocks of polymeric units (about 5 nm) grouped to form the nanoparticle. X-ray diffraction study confirmed the absence of crystalline GB molecules due to its dispersion into the nanoparticles, either entrapped in the polymer chains and/or included into cyclodextrin cavities. GB-loaded nanoparticles induced a significant reduction in the fat content of C. elegans. This hypolipidemic effect was slightly higher for the nanoparticles prepared with coencapsulated HPβCD (8.2%) than for those prepared with βCD (7.9%) or in the absence of cyclodextrins (7.0%). In summary, the coencapsulation of cyclodextrins into poly(anhydride) nanoparticles could be an interesting strategy to develop new oral formulations of glibenclamide.

The construction and characterization of hybrid paclitaxel-in-micelle-in-liposome systems for enhanced oral drug delivery

In this study, novel paclitaxel (PTX) loaded hybrid liposomes for oral PTX delivery were prepared through incorporating PTX loaded polyion complex micelles comprised of positively charged Pluronic F127-Polyethylenimine (PF127-PEI) copolymer and negatively charged sodium cholate (CA) into liposomes consisted of phospholipid molecules. According to the results, this kind of PTX-loaded hybrid liposomes showed improved PTX encapsulation efficiency, sustained PTX release, and enhanced PTX absorption in intestine. The mechanism for enhancing absorption was demonstrated in connection with inhibition of the efflux mediated by multidrug resistance protein, intestinal P-gp. In pharmacokinetic study, the absolute oral bioavailability of PTX loaded in hybrid liposomes had reached to 37.91%. All of these results demonstrated that the application of this novel PTX loaded hybrid liposomes is a strategy with great potential for highly effective oral PTX delivery.

Cyclodextrin-based supramolecular nanoparticles for biomedical applications

Supramolecular host-guest interactions are ideal for engineering supramolecular nanoparticles (SNPs), because their modular character offers the possibility of using the same basic SNPs made of very similar building blocks in a variety of applications. The most widely used host is cyclodextrin (CD), therefore, this review will focus on SNPs involving CD as the host entity. In the first part, particle formation and size control are described, and the forces that induce the assembly between the different components and, therefore, result in the formation of stable and controllable nanoparticles. In the second part, the use of CD-based SNPs for diagnostics and therapeutics is described. Here, the emphasis is on how the therapeutic agent/imaging component is included in the system and how it is released at the target site. CD-based SNPs provide great possibilities for the formulation of nanoparticles for biomedical applications because of their high flexibility, stability, modular character, and biocompatibility.

Effective combination treatment of lung cancer cells by single vehicular delivery of siRNA and different anticancer drugs

In recent years, lung cancer has become one of the fastest growing cancers in the world. Thus, the development of efficient combination therapy to treat lung cancer has attracted significant attention in the cancer therapy field. In this article, we developed a single vehicle drug delivery system, based on quantum dot (QD) nanoparticles, to deliver small interfering RNA (siRNA; target Bcl-2) and different anticancer drugs (carboplatin, paclitaxel, and doxorubicin) simultaneously for treating A549 lung cancer cells efficiently by combination therapy. The QD nanoparticles were conjugated with l-arginine (l-Arg) and different kinds of hydroxypropyl-cyclodextrins (HP-α-CDs, HP-β-CDs, and HP-γ-CDs) on the surface to form the delivery nanocarriers (QD nanocarriers). They were able to not only bind and transport the siRNA through electrostatic interactions with l-Arg residues but also accommodate various disparate anticancer drugs using different HP-CD modifications. Compared with free drug treatments, the use of QD nanocarriers to deliver Bcl-2 siRNA and different anticancer drugs simultaneously exerted a threefold to fourfold increase in cytotoxicity in A549 cells, which greatly improved the treatment efficacy through combined action. Furthermore, the QD nanocarriers could be used as a probe for real-time imaging of the drug delivery and release because of their strong fluorescence properties. These findings indicate that multifunctional QD nanocarriers hold great promise as a powerful tool for combination therapy for lung cancer.

Cyclodextrin-based nanosponges: a versatile platform for cancer nanotherapeutics development

Nanosponges (NSs) are a new age branched cyclodextrin (CD) polymeric systems exhibiting tremendous potential in pharmaceutical, agro science, and biomedical applications. Over the past decade, different varieties of NS based on the type of CD and the crosslinker have been developed tailored for specific applications. NS technology has been instrumental in achieving solubilization, stabilization, sustained release, enhancement of activity, permeability enhancement, protein delivery, ocular delivery, stimuli sensitive drug release, enhancement of bioavailability, etc. There is a major explosion of research in the area of NS-aided cancer therapeutics. A wide of anticancer molecules both from a pharmacological and physicochemical perspective have been developed as NS formulations by several groups including ours. Our objective in this review is to capture a systematic and comprehensive snapshot of the state-of-the-art of NS-aided cancer therapeutics reported so far. This review will provide an ideal platform for both the formulation scientists working on new polymeric/drug development and cancer biologists/scientists to understand the current nanotechnologies in CD-based NS-aided cancer therapeutics. The scope of the review is limited to small molecules and CD-based NS. The review covers in detail the problems associated with anticancer small molecules, and the solution provided by CD-based NS specifically for camptothecin, curcumin, paclitaxel, tamoxifen, resveratrol, quercetin, oxygen-NS, temozolomide, doxorubicin, and 5-Fluorouracil. WIREs Nanomed Nanobiotechnol 2016, 8:579-601. doi: 10.1002/wnan.1384 For further resources related to this article, please visit the WIREs website.

Optimization and bioavailability evaluation of self-microemulsifying drug delivery system of the daidzein–nicotinamide complex

In this study, a DDZ–NCT complex SMEDDS was prepared and optimized to improve the oral bioavailability of the poorly water-soluble drug.

A Comprehensive Review on Cyclodextrin-Based Carriers for Delivery of Chemotherapeutic Cytotoxic Anticancer Drugs

Most of the cytotoxic chemotherapeutic agents have poor aqueous solubility. These molecules are associated with poor physicochemical and biopharmaceutical properties, which makes the formulation difficult. An important approach in this regard is the use of combination of cyclodextrin and nanotechnology in delivery system. This paper provides an overview of limitations associated with anticancer drugs, their complexation with cyclodextrins, loading/encapsulating the complexed drugs into carriers, and various approaches used for the delivery. The present review article aims to assess the utility of cyclodextrin-based carriers like liposomes, niosomes, nanoparticles, micelles, millirods, and siRNA for delivery of antineoplastic agents. These systems based on cyclodextrin complexation and nanotechnology will camouflage the undesirable properties of drug and lead to synergistic or additive effect. Cyclodextrin-based nanotechnology seems to provide better therapeutic effect and sustain long life of healthy and recovered cells. Still, considerable study on delivery system and administration routes of cyclodextrin-based carriers is necessary with respect to their pharmacokinetics and toxicology to substantiate their safety and efficiency. In future, it would be possible to resolve the conventional and current issues associated with the development and commercialization of antineoplastic agents.

The preparation, characterization, and pharmacokinetic studies of chitosan nanoparticles loaded with paclitaxel/dimethyl-β-cyclodextrin inclusion complexes

A novel biocompatible and biodegradable drug-delivery nanoparticle (NP) has been developed to minimize the severe side effects of the poorly water-soluble anticancer drug paclitaxel (PTX) for clinical use. PTX was loaded into the hydrophobic cavity of a hydrophilic cyclodextrin derivative, heptakis (2,6-di-O-methyl)-β-cyclodextrin (DM-β-CD), using an aqueous solution-stirring method followed by lyophilization. The resulting PTX/DM-β-CD inclusion complex dramatically enhanced the solubility of PTX in water and was directly incorporated into chitosan (CS) to form NPs (with a size of 323.9-407.8 nm in diameter) using an ionic gelation method. The formed NPs had a zeta potential of +15.9-23.3 mV and showed high colloidal stability. With the same weight ratio of PTX to CS of 0.7, the loading efficiency of the PTX/DM-β-CD inclusion complex-loaded CS NPs was 30.3-fold higher than that of the PTX-loaded CS NPs. Moreover, it is notable that PTX was released from the DM-β-CD/CS NPs in a sustained-release manner. The pharmacokinetic studies revealed that, compared with reference formulation (Taxol(®)), the PTX/DM-β-CD inclusion complex-loaded CS NPs exhibited a significant increase in AUC(0→24h) (the area under the plasma drug concentration-time curve over the period of 24 hours) and mean residence time by 2.7-fold and 1.4-fold, respectively. Therefore, the novel drug/DM-β-CD inclusion complex-loaded CS NPs have promising applications for the significantly improved delivery and controlled release of the poorly water-soluble drug PTX or its derivatives, thus possibly leading to enhanced therapeutic efficacy and less severe side effects.

Bioavailability enhancement of paclitaxel via a novel oral drug delivery system: paclitaxel-loaded glycyrrhizic acid micelles

Paclitaxel (PTX, taxol), a classical antitumor drug against a wide range of tumors, shows poor oral bioavailability. In order to improve the oral bioavailability of PTX, glycyrrhizic acid (GA) was used as the carrier in this study. This was the first report on the preparation, characterization and the pharmacokinetic study in rats of PTX-loaded GA micelles The PTX-loaded micelles, prepared with ultrasonic dispersion method, displayed small particle sizes and spherical shapes. Differential scanning calorimeter (DSC) thermograms indicated that PTX was entrapped in the GA micelles and existed as an amorphous state. The encapsulation efficiency was about 90%, and the drug loading rate could reach up to 7.90%. PTX-loaded GA micelles displayed a delayed drug release compared to Taxol in the in vitro release experiment. In pharmacokinetic study via oral administration, the area under the plasma concentration-time curve (AUC_{0→24 h}) of PTX-loaded GA micelles was about six times higher than that of Taxol (p < 0.05). The significant oral absorption enhancement of PTX from PTX-loaded GA micelles could be largely due to the increased absorption in jejunum and colon intestine. All these results suggested that GA would be a promising carrier for the oral delivery of PTX.