Chitosan/Sulfobutylether-β-Cyclodextrin Nanoparticles for Ibrutinib Delivery: A Potential Nanoformulation of Novel Kinase Inhibitor

Formulation and evaluation of ibrutinib-loaded glycyrrhizic acid conjugated ovalbumin nanoparticles and ibrutinib-glycyrrhizic acid complex for improved oral bioavailability

The study aimed at enhancing the oral bioavailability of the BCS class 2 drug Ibrutinib (IBR), which exhibits low solubility (0.002 mg/mL) and high permeability (3.9% oral bioavailability). This was achieved through the formulation and evaluation of Ibrutinib-loaded Glycyrrhizic acid conjugated egg ovalbumin nanoparticles (IBR-GA-EA NPs) and Ibrutinib-Glycyrrhizic acid complex (IBR-GA-COMP). The formulation of Ibrutinib-Glycyrrhizic acid complex aimed to enhance the oral bioavailability of Ibrutinib. Lyophilized Ibrutinib-Glycyrrhizic acid complex was prepared and characterized through various studies including DSC, FTIR, in vitro release, and in vivo pharmacokinetics studies. DSC and FTIR confirmed successful formulation development. The nanoparticles exhibited spherical morphology with favourable characteristics: particle size of 194.10 nm, PDI of 0.22, and zeta potential of -33.96 mV. Encapsulation efficiency was 82.88%. In vitro release study displayed major improvement in drug release pattern compared to the free drug suspension. In vivo pharmacokinetic studies demonstrated 3.21-fold and 3.41-fold increase in the oral bioavailability of IBR-GA-EA NPs and IBR-GA-COMP, respectively, compared to IBR suspension alone. The formulated IBR-GA-EA NPs and IBR-GA-COMP are promising drug delivery methods as they successfully improve the solubility and oral bioavailability of Ibrutinib.

The role of macrocycles in supramolecular assembly with polymers

Recently, supramolecular self-assembly has attracted the attention of researchers worldwide because it enables the creation of nanostructures with unique properties without additional costs. Spontaneous organization of molecules allows the design and development of new nanostructures that can interact with drugs and living cells and generate a response. Therefore, supramolecular structures have enormous potential and can be in demand in various fields of healthcare and ecology. One of the widely used building blocks of such supramolecular assemblies is polymers. This review examines the joint aggregation behavior of various macrocycles (cyclodextrins, calixarenes, cucurbiturils, porphyrins, and pillararenes) with polymers, the functional properties of these supramolecular systems and their potential applications.

Precious Cargo: The Role of Polymeric Nanoparticles in the Delivery of Covalent Drugs

Covalent drugs can offer significant advantages over non-covalent drugs in terms of pharmacodynamics (i.e., target-binding properties). However, the development of covalent drugs is sometimes hampered by pharmacokinetic limitations (e.g., low bioavailability, rapid metabolism and toxicity due to off-target binding). Polymeric nanoparticles offer a potential solution to these limitations. Delivering covalent drugs via polymeric nanoparticles provides myriad benefits in terms of drug solubility, permeability, lifetime, selectivity, controlled release and the opportunity for synergistic administration alongside other drugs. In this short review, we examine each of these benefits in turn, illustrated through multiple case studies.

Investigation of Mirabegron-loaded Nanostructured Lipid Carriers for Improved Bioabsorption: Formulation, Statistical Optimization, and In-Vivo Evaluation

Overactive bladder (OAB) is a usual medical syndrome that affects the bladder, and Mirabegron (MBG) is preferred medicine for its control. Currently, available marketed formulations (MYRBETRIQ® granules and MYRBETRIQ® ER tablets) suffer from low bioavailability (29-35%) hampering their therapeutic effectiveness and compromising patient compliance. By creating MBG nanostructured lipid carriers (MBG-NLCs) for improved systemic availability and drug release, specifically in oral administration of OAB treatment, this study aimed to address these issues. MBG-NLCs were fabricated using a hot-melt ultrasonication technique. MBG-GMS; MBG-oleic acid interaction was assessed by in silico molecular docking. QbD relied on the concentration of Span 80 (X1) and homogenizer speed (X2) as critical material attribute (CMA) and critical process parameter (CPP) respectively, while critical quality attributes (CQA) such as particle size (Y1) and cumulative drug release at 24 h (Y2) were estimated as dependent variables. 32 factorial design was utilized to investigate the interconnection in variables that are dependent and independents. Optimized MBG-NLCs with a particle size of 194.4 ± 2.25 nm were suitable for lymphatic uptake. A PDI score of 0.275 ± 0.02 and zeta potential of -36.2 ± 0.721 mV indicated a uniform monodisperse system with stable dispersion properties. MBG-NLCs exhibited entrapment efficiency of 77.3 ± 1.17% and a sustained release in SIF of 94.75 ± 1.60% for 24 h. MBG-NLCs exhibited the Higuchi model with diffusion as a release mechanism. A pharmacokinetic study in Wistar rats exhibited a 1.67-fold higher bioavailability as compared to MBG suspension. Hence, MBG-NLCs hold promise for treating OAB by improving MBG's oral bio absorption.

Macrocycle-Based Supramolecular Drug Delivery Systems: A Concise Review

Efficient delivery of therapeutic agents to the lesion site or specific cells is an important way to achieve "toxicity reduction and efficacy enhancement". Macrocycles have always provided many novel ideas for drug or gene loading and delivery processes. Specifically, macrocycles represented by crown ethers, cyclodextrins, cucurbit[n]urils, calix[n]arenes, and pillar[n]arenes have unique properties, which are different cavity structures, good biocompatibility, and good stability. Benefited from these diverse properties, a variety of supramolecular drug delivery systems can be designed and constructed to effectively improve the physical and chemical properties of guest molecules as needed. This review provides an outlook on the current application status and main limitations of macrocycles in supramolecular drug delivery systems.

Application of sodium sulfobutylether-β-cyclodextrin based on encapsulation

Sodium Sulfobutylether-β-cyclodextrin (SBE-β-CD) is a derivative of β-cyclodextrin, characterized by its stereo structure, which closely resembles a truncated cone with a hydrophobic internal cavity. The solubility of insoluble substances within the hydrophobic cavity is significantly enhanced, reducing contact between the guest and the environment. Consequently, SBE-β-CD is frequently employed as a co-solvent and stabilizer. As the research progresses, it has been observed that the inclusion of SBE-β-CD is reversible and competitive. Besides, some inclusion complexes undergo distinct physicochemical property alterations compared to the guests. Additionally, certain guests exhibit varying inclusions with SBE-β-CD at different concentrations. These features have contributed to the expanding applications. SBE-β-CD finds widespread application in pharmaceutics as a protective agent and pKa regulator, in pharmaceutical analysis as a chiral substance separator, and in biomedical engineering for encapsulating dyes and modifying sensors. The article will elaborate in detail on the physicochemical properties of SBE-β-CD, encapsulation principles, and factors influencing the formation of inclusion complexes. Furthermore, the review focuses on the application of SBE-β-CD through encapsulation in pharmaceutics, pharmaceutical analysis, and biomedical engineering. Finally, the prospects and potential applications of SBE-β-CD are discussed.

Ibrutinib topical delivery for melanoma treatment: The effect of nanostructured lipid carriers' composition on the controlled drug skin deposition

Melanoma is responsible for more than 80% of deaths related to skin diseases. Ibrutinib (IBR), a Bruton's tyrosine kinase inhibitor, has been proposed to treat this type of tumor. However, its low solubility, extensive first-pass effect, and severe adverse reactions with systemic administration affect therapeutic success. This study proposes developing and comparing the performance of two compositions of nanostructured lipid carriers (NLCs) to load IBR for the topical management of melanomas in their early stages. Initially, the effectiveness of IBR on melanoma proliferation was evaluated in vitro, and the results confirmed that the drug reduces the viability of human melanoma cells by inducing apoptosis at a dose that does not compromise dermal cells. Preformulation tests were then conducted to characterize the physical compatibility between the drug and the selected components used in NLCs preparation. Sequentially, two lipid compositions were used to develop the NLCs. Formulations were then characterized and subjected to in vitro release and permeation tests on porcine skin. The NLCs containing oleic acid effectively controlled IBR release over 24 h compared to the NLCs composed of pomegranate seed oil. Furthermore, the nanoparticles acted as permeation enhancers, increasing the fluidity of the lipids in the stratum corneum, as determined by EPR spectroscopy, which stimulated the IBR penetration more profoundly into the skin. However, the NLCs composition also influenced the permeation promotion factor. Thus, these findings emphasize the importance of the composition of NLCs in controlling and increasing the skin penetration of IBR and pave the way for future advances in melanoma therapy.

Exploring oral drug delivery: In vitro release and mathematical modeling of hydrophobic drug (Na-L-thyroxine) and its cyclodextrin inclusion complex in chitosan microparticles

Na-l-Thyroxine (Na-l-Thy) is a frequently prescribed synthetic hormone for hypothyroidism treatment. Despite its efficacy, its hydrophobic nature poses a challenge for achieving optimal bioavailability. To address this, researchers explored various delivery methods, including micro-formulations and nano-formulations, for precise and prolonged release of hydrophobic and hydrophilic drugs. In this study, we developed micro-formulations with cyclodextrin and chitosan. Docking studies identified γ-cyclodextrin as the preferred option for forming a stable complex with Na-l-Thyroxine compared to α, and β-cyclodextrins. Two micro-formulations were prepared compared: Na-l-Thyroxine loaded on chitosan (CS + Na-l-Thy) and Na-l-Thyroxine and γ-cyclodextrin inclusion complex (IC) loaded on chitosan (CS + IC). CS + IC exhibited superior encapsulation efficiency (91.25 %) and loading capacity (18.62 %) compared to CS + Na-l-Thy (encapsulation efficiency: 70.24 %, loading capacity: 21.18 %). Characterization using FTIR, SEM, and TGA validated successful encapsulation of Na-l-Thy in spherical microparticles with high thermal stability. In-vitro release studies at pH 1.2 and 7.4 showed that the CS + IC microparticles displayed gradual, consistent drug release compared to CS + Na-l-Thy -Thy. Both formulations showed faster release at pH 1.2 than at pH 7.4. Reaction kinetics analysis of release studies of CS + Na-l-Thy and CS + IC were best described by Higuchi kinetic model and Korsemeyer-Peppas kinetic model respectively. This study suggests that the CS + IC microparticles are an effective and stable delivery system for sustained release of hydrophobic Na-l-Thy.

Enhanced oral delivery of hesperidin-loaded sulfobutylether-β-cyclodextrin/chitosan nanoparticles for augmenting its hypoglycemic activity: in vitro-in vivo assessment study

Hesperidin (Hsd), a bioactive phytomedicine, experienced an antidiabetic activity versus both Type 1 and Type 2 Diabetes mellitus. However, its intrinsic poor solubility and bioavailability is a key challenging obstacle reflecting its oral delivery. From such perspective, the purpose of the current study was to prepare and evaluate Hsd-loaded sulfobutylether-β-cyclodextrin/chitosan nanoparticles (Hsd/CD/CS NPs) for improving the hypoglycemic activity of the orally administered Hsd. Hsd was first complexed with sulfobutylether-β-cyclodextrin (SBE-β-CD) and the complex (CX) was found to be formed with percent complexation efficiency and percent process efficiency of 50.53 ± 1.46 and 84.52 ± 3.16%, respectively. Also, solid state characterization of the complex ensured the inclusion of Hsd inside the cavity of SBE-β-CD. Then, Hsd/CD/CS NPs were prepared using the ionic gelation technique. The prepared NPs were fully characterized to select the most promising one (F1) with a homogenous particle size of 455.7 ± 9.04 nm, a positive zeta potential of + 32.28 ± 1.12 mV, and an entrapment efficiency of 77.46 ± 0.39%. The optimal formula (F1) was subjected to further investigation of in vitro release, ex vivo intestinal permeation, stability, cytotoxicity, and in vivo hypoglycemic activity. The results of the release and permeation studies of F1 manifested a modulated pattern between Hsd and CX. The preferential stability of F1 was observed at 4 ± 1 °C. Also, the biocompatibility of F1 with oral epithelial cell line (OEC) was retained up to a concentration of 100 µg/mL. After oral administration of F1, a noteworthy synergistic hypoglycemic effect was recorded with decreased blood glucose level until the end of the experiment. In conclusion, Hsd/CD/CS NPs could be regarded as a hopeful oral delivery system of Hsd with enhanced antidiabetic activity.

Supramolecular Arrangement of Doxycycline with Sulfobutylether-β-Cyclodextrin: Impact on Nanostructuration with Chitosan, Drug Degradation and Antimicrobial Potency

Doxycycline (DX) is a well-established and broad-spectrum antimicrobial drug. However, DX has drawbacks, such as physicochemical instability in aqueous media and bacterial resistance. The inclusion of drugs in cyclodextrin complexes and their loading into nanocarriers can overcome these limitations. Thus, we studied the DX/sulfobutylether-β-CD (SBE-β-CD) inclusion complex for the first time and used it to reticulate chitosan. The resulting particles were evaluated by their physicochemical characteristics and antibacterial activity. DX/SBE-β-CD complexes were characterized by nuclear magnetic resonance, infrared spectroscopy, thermal analysis, X-ray diffraction, and scanning electron microscopy (SEM), whereas DX-loaded nanoparticles were characterized by dynamic light scattering, SEM, and drug content. The partial inclusion of the DX molecule in CD happened in a 1:1 proportion and brought increased stability to solid DX upon thermal degradation. Chitosan-complex nanoparticles measured approximately 200 nm, with a narrow polydispersity and particles with sufficient drug encapsulation for microbiological studies. Both formulations preserved the antimicrobial activity of DX against Staphylococcus aureus, whereas DX/SBE-β-CD inclusion complexes were also active against Klebsiella pneumoniae, indicating the potential use of these formulations as drug delivery systems to treat local infections.

Host-guest drug delivery by β-cyclodextrin assisted polysaccharide vehicles: A review

Among different form of cyclodextrin (CD), β-CD has been taken a special attraction in pharmaceutical science due to lowest aqueous solubility and adequate cavity size. When β-CD forms inclusion complex with drugs then biopolymers such as polysaccharides in combination plays a vital role as a vehicle for safe release of drugs. It is noticed that, β-CD assisted polysaccharide-based composite achieves better drug release rate through host-guest mechanism. Present review is a critical analysis of this host-guest mechanism for release of drugs from polysaccharide supported β-CD inclusion complex. Various important polysaccharides such as cellulose, alginate, chitosan, dextran, etc. in relevant to drug delivery are logically compared in present review by their association with β-CD. Efficacy of mechanism of drug delivery by different polysaccharides with β-CD is analytically examined in schematic form. Drug release capacity at different pH conditions, mode of drug release, along with characterization techniques adopted by individual polysaccharide-based CD complexes are comparatively established in tabular form. This review may explore better visibility for researchers those are working in the area of controlled release of drugs by vehicle consist of β-CD associated polysaccharide composite through host-guest mechanism.

Cyclodextrin-Based Arsenal for Anti-Cancer Treatments

Anti-cancer drugs are mostly limited in their use due to poor physicochemical and biopharmaceutical properties. Their lower solubility is the most common hurdle limiting their use upto their potential. In the recent years, the cyclodextrin (CD) complexation have emerged as existing approach to overcome the problem of poor solubility. CD-based nano-technological approaches are safe, stable and showed well in vivo tolerance and greater payload for encapsulation of hydrophobic drugs for the targeted delivery. They are generally chosen due to their ability to get self-assembled to form liposomes, nanoparticles, micelles and nano-sponges etc. This review paper describes a birds-eye view of the various CD-based nano-technological approaches applied for the delivery of anti-cancer moieties to the desired target such as CD based liposomes, niosomes, niosoponges, micelles, nanoparticles, monoclonal antibody, magnetic nanoparticles, small interfering RNA, nanorods, miscellaneous formulation of anti-cancer drugs containing CD. Moreover, the author also summarizes the various shortcomings of such a system and their way ahead.

Improved oral nutraceutical-based intervention for the management of obesity: pterostilbene-loaded chitosan nanoparticles

Aim: To formulate and assess the oral anti-obesity effect of polymeric-based pterostilbene (PS)-loaded nanoparticles. Methods: Pterostilbene-hydroxypropyl β-cyclodextrin inclusion complex loaded in chitosan nanoparticles (PS/HPβCD-NPs) were prepared and characterized in vitro. Cytotoxicity, pharmacokinetics and anti-obesity effects were assessed on Caco-2 cell line and high-fat-diet-induced obesity rat model, respectively. In vivo assessment included histological examination, protein and gene expression of obesity biomarkers in adipose tissues. Results: Safe PS/HPβCD-NPs were successfully prepared with improved bioavailability compared with free PS. PS/HPβCD-NPs showed an improved anti-obesity effect, as supported by histological examination, lipid profile, UCP1 gene expression and protein expression of SIRT1, COX2, IL-6 and leptin. Conclusion: Orally administered PS nanoparticles represent a new and promising anti-obesity strategy owing to the sustainable weight loss and minimal side effects; this may be of great socio-economic impact.

Chitosan/sulfobutylether-β-cyclodextrin based nanoparticles coated with thiolated hyaluronic acid for indomethacin ophthalmic delivery

Indomethacin (IND) is topically administered for the treatment of the anterior segment diseases such as conjunctivitis, uveitis, and inflammation prevention for post-cataract surgery, as well as posterior segment diseases as macular edema. Currently IND is available as 0.1% w/v hydroxypropyl-β-cyclodextrin-based eye drop formulation and its bioavailability is limited by several drawbacks such as the nasolacrimal duct draining, the reflex blinking and the low volume of the conjunctival sac. In this study, chitosan (CS)/sulfobutylether-β-cyclodextrin (SBE-β-CD) based nanoparticles (NPs) with a mean diameter of 340 (±7) nm, a ζ-potential value of +18.3 (±0.5) mV and coated with thiolated low molecular weight hyaluronic acid were formulated to improve both the solubility and the residential time in the conjunctival sac of the loaded drug IND. The NPs were prepared through the ionotropic gelation technique, exploiting the interaction between the positively charged amino group of CS and the negatively charged sulfonic group of SBE-β-CD. The mucoadhesive properties of the NPs were evaluated on chicken trachea and esophagus tissues using a texture analyser. The irritability effects of NPs were disclaimed with Hecam test. The developed coated NPs showed increased residential time in the conjunctival sac, displayed no irritancy or toxicity for local administration, making them an optimal and innovative drug delivery system for the treatment of anterior segment inflammation diseases. On the other hand, the uncoated NPs displayed better permeating properties since they are smaller and could be further exploited for the treatment of posterior segment diseases.

Inclusion Complex of Isoliquiritigenin With Sulfobutyl Ether-β-Cyclodextrin: Preparation, Characterization, Inclusion Mode, Solubilization, and Stability

Isoliquiritigenin (ISL) possesses a wide variety of pharmacological properties, however, its poor solubility and oral bioavailability pose a significant barrier to its application. In present studies, the ISL inclusion complex was prepared with sulfobutyl ether-β-cyclodextrin (SBE-β-CD). The physicochemical characterizations of ISL-SBE-β-CD were performed with Fourier transform infrared (FT-IR) spectroscopy and X-ray powder diffraction (XRD). Phase solubility study suggested a 1:1 formation of ISL-SBE-β-CD complexes. The water solubility of ISL rose from 13.6 μM to 4.05 mM by the inclusion of SBE-β-CD. The antioxidant activities (IC50) of ISL-SBE-β-CD reached 42.2 μg/ml, which was significantly lower than that of ISL (60.5 μg/ml). Its stability in biological environments was also enhanced.

Preparation of Doxorubicin-Loaded Carboxymethyl-β-Cyclodextrin/Chitosan Nanoparticles with Antioxidant, Antitumor Activities and pH-Sensitive Release

In this study, chitosan nanoparticles (HF-CD NPs) were synthesized by an ionic gelation method using negatively charged carboxymethyl-β-cyclodextrin and positively charged 2-hydroxypropyltrimethyl ammonium chloride chitosan bearing folic acid. The surface morphology of HF-CD NPs was spherical or oval, and they possessed relatively small particle size (192 ± 8 nm) and positive zeta potential (+20 ± 2 mV). Meanwhile, doxorubicin (Dox) was selected as model drug to investigate the prepared nanoparticles’ potential to serve as a drug delivery carrier. The drug loading efficiency of drug-loaded nanoparticles (HF-Dox-CD NPs) was 31.25%. In vitro release profiles showed that Dox release of nanoparticles represented a pH-sensitive sustained and controlled release characteristic. At the same time, the antioxidant activity of nanoparticles was measured, and chitosan nanoparticles possessed good antioxidant activity and could inhibit the lipid peroxidation inside the cell and avoid material infection. Notably, CCK-8 assay testified that the nanoparticles were safe drug carriers and significantly enhanced the antitumor activity of Dox. The nanoparticles possessed good antioxidant activity, pH-sensitive sustained controlled release, enhanced antitumor activity, and could be expected to serve as a drug carrier in future with broad application prospects.

Enhanced Oral Bioavailability of Epalrestat SBE7-β-CD Complex Loaded Chitosan Nanoparticles: Preparation, Characterization and in-vivo Pharmacokinetic Evaluation

Background

Epalrestat (EPL) is a carboxylic acid derivative with poor aqueous solubility and its pharmacokinetic features are not fully defined.

Purpose

Current research aimed to fabricate inclusion complexation of EPL with SBE₇ β-CD (IC) and EPL/SBE₇ β-CD CS NPs (NP).

Methods

EPL was complexed with SBE₇ β-CD using the co-precipitation method, and the prepared complex was fabricated into nanoparticles using the ionic gelation method. The prepared formulations were characterized for particle size analysis, surface morphology, and in vitro dissolution study. The % inhibition of EPL against α-glucosidase enzyme was also conducted to check the drug’s antidiabetic activity. Finally, an in vivo pharmacokinetic investigation was carried out to determine the concentration of EPL in rabbit plasma of the prepared formulation. In vivo pharmacokinetic studies were conducted by giving a single dose of pure EPL, IC, and NP.

Results

The size of NP was found to be 241.5 nm with PDI 0.363 and zeta potential of +31.8 mV. The surface of the prepared NP was non-porous, smooth and spherical when compared with pure EPL, SBE₇ β-CD and IC. The cumulative drug release (%) from IC and NP was 73% and 88%, respectively, as compared to pure drug (25%). The % inhibition results for in vitro α-glucosidase was reported to be 74.1% and the predicted binding energy for in silico molecular docking was calculated to be −6.6 kcal/mol. The calculated C_max values for EPL, IC and NP were 4.75±3.64, 66.91±7.58 and 84.27±6.91 μg/mL, respectively. The elimination half-life of EPL was 4 h and reduced to 2 h for IC and NP. The AUC_0-α for EPL, IC and NP were 191.5±164.63, 1054.23±161.77 and 1072.5±159.54 μg/mL*h, respectively.

Conclusion

Taking these parameters into consideration it can be concluded that IC and NP have prospective applications for greatly improved delivery and regulatedt release of poorly water soluble drugs, potentially leading to increase therapeutic efficacy and fewer side effects.

Nanomedicines in B cell-targeting therapies

B cells play multiple roles in immune responses related to autoimmune diseases as well as different types of cancers. As such, strategies focused on B cell targeting attracted wide interest and developed intensively. There are several common mechanisms various B cell targeting therapies have relied on, including direct B cell depletion, modulation of B cell antigen receptor (BCR) signaling, targeting B cell survival factors, targeting the B cell and T cell costimulation, and immune checkpoint blockade. Nanocarriers, used as drug delivery vehicles, possess numerous advantages to low molecular weight drugs, reducing drug toxicity, enhancing blood circulation time, as well as augmenting targeting efficacy and improving therapeutic effect. Herein, we review the commonly used targets involved in B cell targeting approaches and the utilization of various nanocarriers as B cell-targeted delivery vehicles. STATEMENT OF SIGNIFICANCE: As B cells are engaged significantly in the development of many kinds of diseases, utilization of nanomedicines in B cell depletion therapies have been rapidly developed. Although numerous studies focused on B cell targeting have already been done, there are still various potential receptors awaiting further investigation. This review summarizes the most relevant studies that utilized nanotechnologies associated with different B cell depletion approaches, providing a useful tool for selection of receptors, agents and/or nanocarriers matching specific diseases. Along with uncovering new targets in the function map of B cells, there will be a growing number of candidates that can benefit from nanoscale drug delivery.

Tyrosine kinase inhibitors as next generation oncological therapeutics: Current strategies, limitations and future perspectives

Protein kinases, a class of enzymes that govern various biological phenomena at a cellular level, are responsible for signal transduction in cells that regulate cellular proliferation, differentiation, and growth. Protein kinase enzyme mutation results in abnormal cell division leading to a pathological condition like cancer. Tyrosine kinase (TK) inhibitors, which helps as a potential drug candidate for the treatment of cancer, are continuously being developed. Majority of these drug candidates are being administered as conventional oral dosage form, which provides limited safety and efficacy due to non-specific delivery and uncontrolled biodistribution resulting into the adverse effects. A controlled drug delivery approach for the delivery of TK inhibitors may be a potential strategy with significant safety and efficacy profile. Novel drug delivery strategies provide target-specific drug delivery, improved pharmacokinetic behaviour, and sustained release leading to lower doses and dosing frequency with significantly reduced side effects. Along with basic aspects of tyrosine kinase, this review discusses various aspects related to the application of tyrosine kinase inhibitors in clinical oncological setting. Furthermore, the limitations/challenges and formulation advancements related to this class of candidates particularly for cancer management have been reviewed. It is expected that innovations in drug delivery approaches for TK inhibitors using novel techniques will surely provide a new insights for improved cancer treatment and patients' life quality.

Temperature-Dependent Dynamical Evolution in Coum/SBE-β-CD Inclusion Complexes Revealed by Two-Dimensional FTIR Correlation Spectroscopy (2D-COS)

A combination of Fourier transform infrared spectroscopy in attenuated total reflectance geometry (FTIR-ATR) and 2D correlation analysis (2D-COS) was applied here for the first time in order to investigate the temperature-dependent dynamical evolution occurring in a particular type of inclusion complex, based on sulfobutylether-β-cyclodextrin (SBE-β-CD) as hosting agent and Coumestrol (7,12-dihydorxcoumestane, Coum), a poorly-soluble active compound known for its anti-viral and anti-oxidant activity. For this purpose, synchronous and asynchronous 2D spectra were calculated in three different wavenumber regions (960-1320 cm^-1, 1580-1760 cm^-1 and 2780-3750 cm^-1) and over a temperature range between 250 K and 340 K. The resolution enhancement provided by the 2D-COS offers the possibility to extract the sequential order of events tracked by specific functional groups of the system, and allows, at the same time, the overcoming of some of the limits associated with conventional 1D FTIR-ATR analysis. Acquired information could be used, in principle, for the definition of an optimized procedure capable to provide high-performance T-sensitive drug carrier systems for different applications.

Curcumin Encapsulated in Crosslinked Cyclodextrin Nanoparticles Enables Immediate Inhibition of Cell Growth and Efficient Killing of Cancer Cells

The efficiency of anti-cancer drugs is commonly determined by endpoint assays after extended incubation times, often after days. Here we demonstrate that curcumin encapsulated in crosslinked cyclodextrin nanoparticles (CD-NP) acts extremely rapidly on cell metabolism resulting in an immediate and complete inhibition of cell growth and in efficient cancer-cell killing only few hours after incubation. This early onset of anti-cancer action was discovered by live-cell high-throughput fluorescence microscopy using an environmental stage. To date, only very few examples of covalently crosslinked nanoscale CD-based (CD-NP) drug carriers exist. Crosslinking cyclodextrins enables the adsorption of unusually high payloads of hydrophobic curcumin (762 µg CC/mg CD-NP) reflecting a molar ratio of 2.3:1 curcumin to cyclodextrin. We have investigated the effect of CD-NP encapsulated curcumin (CD-CC-NP) in comparison to free, DMSO-derived curcumin nanoparticles (CC-NP) on 4 different cell lines. Very short incubations times as low as 1 h were applied and cell responses after medium change were subsequently followed over two days. We show that cell proliferation is inhibited nearly immediately in all cell lines and that a cell- and concentration dependent cancer-cell killing occurs. Anti-cancer effects were similar with free and encapsulated curcumin, however, encapsulation in CD-NP drastically extends the long-term photostability and anti-cancer activity of curcumin. Curcumin-sensitivity is highest in HeLa cells reaching up to 90% cell death under these conditions. Sensitivity decreased from HeLa to T24 to MDA MB-231 cells. Strikingly, the immortalized non-cancerous cell line MCF-10A was robust against curcumin concentrations that were highly toxic to the other cell lines. Our results underline the potential of curcumin as gentle and yet effective natural anti-cancer agent when delivered solvent-free in stabilizing and biocompatible drug carriers such as CD-NP that enable efficient cellular delivery.

Phytochemical delivery through nanocarriers: a review

In recent times, phytochemicals encapsulated or conjugated with nanocarriers for delivery to the specific sites have gained considerable research interest. Phytochemicals are mostly plant secondary metabolites which reported to be beneficial for human health and in disease theraphy. However, these compound are large size and polar nature of these compounds, make it difficult to cross the blood-brain barrier (BBB), endothelial lining of blood vessels, gastrointestinal tract and mucosa. Moreover, they are enzymatically degraded in the gastrointestinal tract. Therefore, encapsulation or conjugation of these compounds with nanocrriers could be an alternate way to enhance their bioefficacy by influencing their gastrointestinal stability, rate of absorption and dispersion. This review presents an overview of nanocarriers alternatives which improves therapeutic value and avoid toxicity, by releasing bioactive compounds specifically at target tissues with enhanced stability and bioavailability. Future investigations may emphasize on deciphering the structural changes in nanocarriers during digestion and absorption, the difference between in-vitro and in-vivo digestion simulations, and impact of nanocarriers on the metabolism of phytochemicals.

In vitro and in vivo evaluations on nanoparticle and phospholipid hybrid nanoparticles with absorption enhancers for oral insulin delivery

Oral delivery of peptide and proteins is challenging due to their poor physical and chemical stability which usually results in inadequate therapeutic efficacy. Nanoparticles encapsulating insulin was developed by the ionic gelation technique using sulfobutyl ether-β-cyclodextrin as an anionic linker. Phospholipid hybrid nanoparticles were formulated by utilizing ionic gelation and thin-film hydration methods using D-α-Tocopheryl polyethylene glycol 1000 succinate, sodium deoxycholate separately and in combination to take the advantage of liposomes and nanoparticles also various absorption enhancement mechanisms. All formulations were characterized and tested for in vitro gastrointestinal stability, in vitro drug release, and cytotoxicity. On the other hand, in vivo effects of developed formulations on reducing blood glucose levels were monitored for 8 hours. Phospholipid hybrid nanoparticles including D-α-Tocopheryl polyethylene glycol 1000 succinate and sodium deoxycholate in combination with 548.7 nm particle size, 0.332 polydispersity index, 22.0 mV zeta potential, and 61.9% encapsulation efficiency, exhibited desired gastrointestinal stability and insulin release in vitro. In addition, the formulation proved its safety with cytotoxicity studies on L929 cells. The subjected phospholipid hybrid nanoparticle formulation was found to be the most effective formulation by reducing and maintaining blood glucose levels with avoiding fluctuations.

Affinity-Based Polymers Provide Long-Term Immunotherapeutic Drug Delivery Across Particle Size Ranges Optimal for Macrophage Targeting

Drug delivery to specific arms of the immune system can be technically challenging to provide prolonged drug release while limiting off-target toxicity given the limitations of current drug delivery systems. In this work, we test the design of a cyclodextrin (CD) polymer platform to extend immunomodulatory drug delivery via affinity interactions for sustained release at multiple size scales. The parameter space of synthesis variables influencing particle nucleation and growth (pre-incubation time and stirring speed) and post-synthesis grinding effects on resulting particle diameter were characterized. We demonstrate that polymerized CD forms exhibit size-independent release profiles of the small molecule drug lenalidomide (LND) and can provide improved drug delivery profiles versus macro-scale CD polymer disks in part due to increased loading efficiency. CD polymer microparticles and smaller, ground particles demonstrated no significant cytotoxicity as compared to the base CD monomer when co-incubated with fibroblasts. Uptake of ground CD particles was significantly higher following incubation with RAW 264.7 macrophages in culture over standard CD microparticles. Thus, the affinity/structure properties afforded by polymerized CD allow particle size to be modified to affect cellular uptake profiles independently of drug release rate for applications in cell-targeted drug delivery.

Self-Assembly of Amphiphilic Compounds as a Versatile Tool for Construction of Nanoscale Drug Carriers

This review focuses on synthetic and natural amphiphilic systems prepared from straight-chain and macrocyclic compounds capable of self-assembly with the formation of nanoscale aggregates of different morphology and their application as drug carriers. Since numerous biological species (lipid membrane, bacterial cell wall, mucous membrane, corneal epithelium, biopolymers, e.g., proteins, nucleic acids) bear negatively charged fragments, much attention is paid to cationic carriers providing high affinity for encapsulated drugs to targeted cells. First part of the review is devoted to self-assembling and functional properties of surfactant systems, with special attention focusing on cationic amphiphiles, including those bearing natural or cleavable fragments. Further, lipid formulations, especially liposomes, are discussed in terms of their fabrication and application for intracellular drug delivery. This section highlights several features of these carriers, including noncovalent modification of lipid formulations by cationic surfactants, pH-responsive properties, endosomal escape, etc. Third part of the review deals with nanocarriers based on macrocyclic compounds, with such important characteristics as mucoadhesive properties emphasized. In this section, different combinations of cyclodextrin platform conjugated with polymers is considered as drug delivery systems with synergetic effect that improves solubility, targeting and biocompatibility of formulations.