Surface-modified PLGA nanoparticles with chitosan for oral delivery of tolbutamide

Layer-by-Layer Assembly of Renal-Targeted Polymeric Nanoparticles for Robust Arginase-2 Knockdown and Contrast-Induced Acute Kidney Injury Prevention

The mitochondrial enzyme arginase-2 (Arg-2) is implicated in the pathophysiology of contrast-induced acute kidney injury (CI-AKI). Therefore, Arg-2 represents a candid target for CI-AKI prevention. Here, layer-by-layer (LbL) assembled renal-targeting polymeric nanoparticles are developed to efficiently deliver small interfering RNA (siRNA), knockdown Arg-2 expression in renal tubules, and prevention of CI-AKI is evaluated. First, near-infrared dye-loaded poly(lactic-co-glycolic acid) (PLGA) anionic cores are electrostatically coated with cationic chitosan (CS) to facilitate the adsorption and stabilization of Arg-2 siRNA. Next, nanoparticles are coated with anionic hyaluronan (HA) to provide protection against siRNA leakage and shielding against early clearance. Sequential electrostatic layering of CS and HA improves loading capacity of Arg-2 siRNA and yields LbL-assembled nanoparticles. Renal targeting and accumulation is enhanced by modifying the outermost layer of HA with a kidney targeting peptide (HA-KTP). The resultant kidney-targeting and siRNA loaded nanoparticles (PLGA/CS/HA-KTP siRNA) exhibit proprietary accumulation in kidneys and proximal tubular cells at 24 h post-tail vein injection. In iohexol-induced in vitro and in vivo CI-AKI models, PLGA/CS/HA-KTP siRNA delivery alleviates oxidative and nitrification stress, and rescues mitochondrial dysfunction while reducing apoptosis, thereby demonstrating a robust and satisfactory therapeutic effect. Thus, PLGA/CS/HA-KTP siRNA nanoparticles offer a promising candidate therapy to protect against CI-AKI.

The role of artificial intelligence in generating original scientific research

Artificial intelligence (AI) is a revolutionary technology that is finding wide application across numerous sectors. Large language models (LLMs) are an emerging subset technology of AI and have been developed to communicate using human languages. At their core, LLMs are trained with vast amounts of information extracted from the internet, including text and images. Their ability to create human-like, expert text in almost any subject means they are increasingly being used as an aid to presentation, particularly in scientific writing. However, we wondered whether LLMs could go further, generating original scientific research and preparing the results for publication. We taskedGPT-4, an LLM, to write an original pharmaceutics manuscript, on a topic that is itself novel. It was able to conceive a research hypothesis, define an experimental protocol, produce photo-realistic images of 3D printed tablets, generate believable analytical data from a range of instruments and write a convincing publication-ready manuscript with evidence of critical interpretation. The model achieved all this is less than 1 h. Moreover, the generated data were multi-modal in nature, including thermal analyses, vibrational spectroscopy and dissolution testing, demonstrating multi-disciplinary expertise in the LLM. One area in which the model failed, however, was in referencing to the literature. Since the generated experimental results appeared believable though, we suggest that LLMs could certainly play a role in scientific research but with human input, interpretation and data validation. We discuss the potential benefits and current bottlenecks for realising this ambition here.

Alomrani A. Optimization of Bromocriptine-Mesylate-Loaded Polycaprolactone Nanoparticles Coated with Chitosan for Nose-to-Brain Delivery: In Vitro and In Vivo Studies

Bromocriptine mesylate (BM), primarily ergocryptine, is a dopamine agonist derived from ergot alkaloids. This study aimed to formulate chitosan (CS)-coated poly ε-caprolactone nanoparticles (PCL NPs) loaded with BM for direct targeting to the brain via the nasal route. PCL NPs were optimized using response surface methodology and a Box-Behnken factorial design. Independent formulation parameters for nanoparticle attributes, including PCL payload (A), D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) concentration (B), and sonication time (C), were investigated. The dependent variables were nanoparticle size (Y1), zeta potential (Y2), entrapment efficiency (EE; Y3), and drug release rate (Y4). The optimal formulation for BM-PCL NPs was determined to be 50 mg PCL load, 0.0865% TPGS concentration, and 8 min sonication time, resulting in nanoparticles with a size of 296 ± 2.9 nm having a zeta potential of -16.2 ± 3.8 mV, an EE of 90.7 ± 1.9%, and a zero-order release rate of 2.6 ± 1.3%/min. The optimized BM-PCL NPs were then coated with CS at varying concentrations (0.25, 0.5, and 1%) to enhance their effect. The CS-PCL NPs exhibited different particle sizes and zeta potentials depending on the CS concentration used. The highest EE (88%) and drug load (DL; 5.5%) were observed for the optimized BM-CS-PCL NPs coated with 0.25% CS. The BM-CS-PCL NPs displayed a biphasic release pattern, with an initial rapid drug release lasting for 2 h, followed by a sustained release for up to 48 h. The 0.25% CS-coated BM-CS-PCL NPs showed a high level of permeation across the goat nasal mucosa, with reasonable mucoadhesive strength. These findings suggested that the optimized 0.25% CS-coated BM-CS-PCL NPs hold promise for successful nasal delivery, thereby improving the therapeutic efficacy of BM.

Advances in Functionalization of Bioresorbable Nanomembranes and Nanoparticles for Their Use in Biomedicine

Bioresorbable nanomembranes (NMs) and nanoparticles (NPs) are powerful polymeric materials playing an important role in biomedicine, as they can effectively reduce infections and inflammatory clinical patient conditions due to their high biocompatibility, ability to physically interact with biomolecules, large surface area, and low toxicity. In this review, the most common bioabsorbable materials such as those belonging to natural polymers and proteins for the manufacture of NMs and NPs are reviewed. In addition to biocompatibility and bioresorption, current methodology on surface functionalization is also revisited and the most recent applications are highlighted. Considering the most recent use in the field of biosensors, tethered lipid bilayers, drug delivery, wound dressing, skin regeneration, targeted chemotherapy and imaging/diagnostics, functionalized NMs and NPs have become one of the main pillars of modern biomedical applications.

A nano-delivery system based on preventing degradation and promoting absorption to improve the oral bioavailability of insulin

Oral insulin delivery can improve patient compliance and simulate the portal-peripheral insulin concentration gradient produced by endogenous insulin, so oral insulin delivery has a broad prospect. However, some characteristics of the gastrointestinal tract, lead to low oral bioavailability. Therefore, a "ternary mutual-assist" nano-delivery system based on poly(lactide-co-glycolide) (PLGA) as the backbone combined with ionic liquids (IL) and vitamin B12-chitosan (VB12-CS) was constructed in this study, the protein protection performance of IL improves the room temperature stability of the loaded insulin during nanocarrier preparation, transportation and storage to a certain extent, and the protein protection function of IL combined with the slow degradation property of PLGA and the pH-responsive function of VB12-CS to prevent the degradation of insulin in the gastrointestinal tract. In addition, the mucosal adhesion function of VB12-CS, VB12 receptor- and clathrin-mediated transcellular transport involving VB12-CS and IL, and paracellular transport mediated by IL and CS can be combined to improve the intestinal epithelial transport efficiency of insulin, thus, the nanocarrier has stronger preventing degradation and promoting absorption effects. Pharmacodynamic studies showed that after oral administration of VB12-CS-PLGA@IL@INS NPs to diabetic mice, the blood glucose level decreased to about 13 mmol/L, below the critical point of 16.7 mmol/L, and the blood glucose reached a normal level, which was 0.4 times of the blood glucose value before administration, its relative pharmacological bioavailability was 31.8 %, higher than the general nanocarriers (10-20 %) and more beneficial to the clinical transformation of oral insulin.

Colon-specific delivery of methotrexate using hyaluronic acid modified pH-responsive nanocarrier for the therapy of colitis in mice

Oral immunosuppressant methotrexate (MTX) is an effective method for the treatment of inflammatory bowel disease (IBD). To overcome the defects of clinical application of MTX, poly (lactic-co-glycolic acid) (PLGA), Eudragits® S100 (ES100), chitosan (CS) and hyaluronic acid (HA) were used to structure the MTX-loaded HA-CS/ES100/PLGA nanoparticles (MTX@hCEP). MTX@hCEP had a hydrodynamic particle size of approximately 202.5 nm, narrow size distribution, negative zeta potential (-18.7 mV), and smooth surface morphology. In vitro drug release experiments under simulated gastrointestinal conditions indicated that MTX@hCEP exhibited colonic pH-sensitive drug release properties. The cellular uptake capacity of hCEP nanoparticles was significantly enhanced in RAW 264.7 macrophages. Moreover, we further found that the MTX@hCEP also inhibited the proliferation and the secretion of pro-inflammatory cytokines in the LPS-stimulated macrophages. In vivo imaging results not only demonstrated that the accumulated in the colon of colitis mice, but also indicated the extended retention time of MTX in the colon. Additionally, MTX@hCEP alleviated inflammatory symptoms via decreasing the activities of myeloperoxidase and pro-inflammatory factors, promoting mucosal repair in vivo. Collectively, these results clearly demonstrated that MTX@hCEP with properties of colon-specific and macrophages targeting can be exploited as an efficient nanotherapeutic for IBD therapy.

Chitosan Surface-Modified PLGA Nanoparticles Loaded with Cranberry Powder Extract as a Potential Oral Delivery Platform for Targeting Colon Cancer Cells

Nutraceutical cranberry powder extract (CBPE) has distinct polyphenols inhibiting colon cancer growth and proliferation. However, its oral therapeutic efficacy is hindered because of its low permeability. This study aims to formulate chitosan surface-modified PLGA nanoparticles (CS-PLGA NPs) for encapsulating CBPE and modulating its release rate, permeation, cell targeting, and, therefore, its cytotoxicity. A full 2³ factorial design is employed to scrutinize the effect of lactide/glycolide ratio, PLGA weight, and stabilizer concentrations on entrapment efficiency percentage (EE%), particle size (PS), polydispersity index (PDI), and zeta potential (ZP). The optimum formula (F4) shows spherical particles with a relatively high EE% (72.30 ± 2.86%), an appropriate size of 370.10 ± 10.31 nm, PDI; 0.398 ± 0.001, and ZP; -5.40 ± 0.21 mV. Alongside the ATR-FTIR outcomes, the chitosan surface-modified formula (CS-F4) demonstrates a significant increase in particle size (417.67 ± 6.77 nm) and a shift from negative to positive zeta potential (+21.63 ± 2.46 mV), confirming the efficiency of surface modification with chitosan. The intestinal permeability of F4 and CS-F4 is significantly increased by 2.19- and 3.10-fold, respectively, compared to the CBPE solution, with the permeability coefficient (P_app) being 2.05 × 10^-4 cm/min and 2.91 × 10^-4 cm/min, for F4 and CS-F4, respectively, compared to the CBPE solution, 9.36 × 10^-5 cm/min. Moreover, CS-F4 evidences significant caspase-3 protein level expression stimulation and significant inhibition of vascular endothelial growth factor (VEGF) and signal transducer and activator of transcription-3 (STAT-3) protein expression levels, confirming the superiority of CS-F4 for targeting HT-29 cells. Briefly, CS-PLGA NPs could be regarded as a prosperous delivery system of CBPE with enhanced permeation, cell targeting, and antitumor efficacy.

Advanced implications of nanotechnology in disease control and environmental perspectives

Nanotechnology encompasses a wide range of devices derived from biology, engineering, chemistry, and physics, and this scientific field is composed of great collaboration among researchers from several fields. It has diverse implications notably smart sensing technologies, effective disease diagnosis, and sometimes used in treatment. In medical science, the implications of nanotechnology include the development of elements and devices that interact with the body at subcellular (i.e., molecular) levels exhibiting high sensitivity and specificity. There is a plethora of new chances for medical science and disease treatment to be discovered and exploited in the rapidly developing field of nanotechnology. In different sectors, nanomaterials are used just because of their special characteristics. Their large surface area of them enables higher reactivity with greater efficiency. Furthermore, special surface chemistry is displayed by nanomaterials which compare to conventional materials and facilitate the nanomaterials to decrease pollutants efficiently. Recently, nanomaterials are used in some countries to reduce the levels of contaminants in water, air, and soil. Moreover, nanomaterials are used in the cosmetics and medical industry, and it develops the drug discovery (DD) system. Among a huge number of nanomaterials, Cu, Ag, TiO₂, ZnO, Fe₃O₄, and carbon nanotubes (CNTs) are extensively used in different industries for various purposes. This extensive review study has introduced the major scientific and technical features of nanotechnology, as well as some possible clinical applications and positive feedback in environmental waste management and drug delivery systems.

Controlled synthesis of in-situ gold nanoparticles onto chitosan functionalized PLGA nanoparticles for oral insulin delivery

Chitosan-based nanoparticles (chitosan nanoparticles (ChNps), chitosan gold Nps (ChAuNps), and chitosan gold Nps functionalized with poly lactic-co-glycolic acid (PLGA) (ChAuNps/PLGA)) were prepared as nanocarriers for insulin to improve its oral uptake. The emulsion solvent diffusion method was employed to functionalize the Nps with PLGA. TEM, SEM, DLS, and zeta potential were conducted to characterize the Nps. The morphological analysis confirmed the formation of spherical Nps with hydrodynamic particle sizes of 138±23, 16±2.2, and 50±9.3 nm for ChNps, ChAuNps, and ChAuNps/PLGA, respectively. Zeta potential measurements indicated two types of Nps, regardless of insulin entrapment, positively charged, (ChNps (+36 ± 4.2, +31 ± 2.2mv)) and ChAuNps (+37 ± 4.3, +33 ± 2.5mv) and negatively charged (ChAuNps/PLGA (-31 ± 2.7, -26 ± 2.1 mv)). The in vitro studies were assessed by measuring the entrapment efficiencies (EE%) and the release profiles of insulin at different pH values. EE% for ChNps, ChAuNps, and ChAuNps/PLGA were 97 ± 1.5, 98.4 ± 1.9, and 99 ± 1.2%, respectively. At an acidic medium, a significant level of insulin retention was observed (96 ± 0.08%) for ChAuNps/PLGA. While a high amount was released at higher pH values over an extended period of time. In vivo studies, diabetic rats treated with insulin-loaded Nps had reduced blood glucose level (BGL) (38 ± 2.8, 35 ± 6.5, and 27 ± 5.6%) for ChNps ChAuNps and ChAuNps/PLGA, respectively. The pharmacological availability (PA%) and bioavailability (FR%) for insulin-loaded ChAuNps/PLGA were 15.8 ± 0.71% and 7.7 ± 0.93%, respectively. Altogether, emphasize the role of biocompatible Nps and their efficiency in the convenient delivery of insulin, thus lowering the BGL in a safe condition.

Design and Fabrication of Nanofibrous Dura Mater with Antifibrosis and Neuroprotection Effects on SH-SY5Y Cells

The development and treatment of some diseases, such as large-area cerebral infarction, cerebral hemorrhage, brain tumor, and craniocerebral trauma, which may involve the injury of the dura mater, elicit the need to repair this membrane by dural grafts. However, common dural grafts tend to result in dural adhesions and scar tissue and have no further neuroprotective effects. In order to reduce or avoid the complications of dural repair, we used PLGA, tetramethylpyrazine, and chitosan as raw materials to prepare a nanofibrous dura mater (NDM) with excellent biocompatibility and adequate mechanical characteristics, which can play a neuroprotective role and have an antifibrotic effect. We fabricated PLGA NDM by electrospinning, and then chitosan was grafted on the nanofibrous dura mater by the EDC-NHS cross-linking method to obtain PLGA/CS NDM. Then, we also prepared PLGA/TMP/CS NDM by coaxial electrospinning. Our study shows that the PLGA/TMP/CS NDM can inhibit the excessive proliferation of fibroblasts, as well as provide a sustained protective effect on the SH-SY5Y cells treated with oxygen–glucose deprivation/reperfusion (OGD/R). In conclusion, our study may provide a new alternative to dural grafts in undesirable cases of dural injuries.

Development of an Insulin Nano-Delivery System through Buccal Administration

AIM

To develop a new nano-delivery system for insulin buccal administration.

BACKGROUND

Biodegradable polymeric nanoparticles (PNPs) had viewed countless breakthroughs in drug delivery systems. The main objective of PNPs application in delivering and carrying different promising drugs is to make sure that the drugs being delivered to their action sites. As a result maximizing the desired effect and overcoming their limitations and drawbacks.

OBJECTIVES

The main goals of this study were to produce an insulin consumable nano-delivery system for buccal administration and enhance the mucoadhesive effect in sustaining insulin release.

METHODS

Water in oil in water (W-O-W) microemulsion solvent evaporation technique was used for the preparation of nanoparticles consisting from positively charged poly (D, L-lactide-co-glycolide) coated with chitosan and loaded with insulin. Later, a consumable buccal film was prepared by the spin coating method and loaded with the previously prepared nanoparticles.

RESULTS

The newly prepared nanoparticle was assessed in terms of size, charge and surface morphology using a Scanning Electron Microscope (SEM), zeta potential, Atomic Force Microscope (AFM), and Fourier Transform Infra-red (FTIR) spectroscopy. An in-vitro investigation of the insulin release, from nanoparticles and buccal film, demonstrated controlled as well as sustained delivery over 6 hrs. The cumulative insulin release decreased to about (28.9%) with buccal film in comparing with the nanoparticle (50 %).

CONCLUSION

The buccal film added another barrier for insulin release. Therefore, the release was sustained.

MMP-12 siRNA improves the homeostasis of the small intestine and metabolic dysfunction in high-fat diet feeding-induced obese mice

The changes of small intestinal homeostasis have been recognized to contribute essentially to the obese development. However, the core small intestinal regulator which mediates over-nutrient impacts on the homeostasis of the small intestines remains elusive. Here, we identify the MMP-12 as such a responsive factor in mouse small intestines. Taking advantages of the nano delivery system, we demonstrate that small intestine-specific MMP-12 knockdown alleviates high-fat diet feeding-induced metabolic disorders and improves intestinal homeostasis in mice, including a significant decrease in lipid transportation, bile acid reabsorption, and inflammation. In parallel, the small intestinal integrity is recovered and the gut microbiota composition is reversed towards that under normal diet feeding. Mechanistically, MMP-12, differing from its traditional elastolytic function, acts as a transcriptional factor to activate Fabp4 transcription through epigenetic modification. In translational medicine, clinical applications of our nanosystem and therapeutic interventions targeting MMP-12 will benefit patients with obesity and associated diseases.

Surface modification of nano-drug delivery systems for enhancing antibiotic delivery and activity

Rampant antimicrobial resistance calls for innovative strategies to effectively control bacterial infections, enhance antibacterial efficacy, minimize side effects, and protect existing antibiotics in the market. Therefore, to enhance the delivery of antibiotics and increase their bioavailability and accumulation at the site of infection, the surfaces of nano-drug delivery systems have been diversely modified. This strategy applies various covalent and non-covalent techniques to introduce specific coating materials that have been found to be effective against various sensitive and resistant microorganisms. In this review, we discuss the techniques of surface modification of nanocarriers loaded with antibacterial agents. Furthermore, saccharides, polymers, peptides, antibiotics, enzymes and cell membranes coatings that have been used for surface functionalization of nano-drug delivery systems are described, emphasizing current approaches for enhancing delivery, bioavailability, and efficacy of surface-modified antibacterial nanocarriers at infection sites. This article offers a critical overview of the potential of surface-modified antibacterial nanocarriers to overcome the limitations of conventional antibiotics in the treatment of bacterial infections. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

Evaluating the Anticarcinogenic Activity of Surface Modified/Functionalized Nanochitosan: The Emerging Trends and Endeavors

Chitosan begins its humble journey from marine food shell wastes and ends up as a versatile nutraceutical. This review focuses on briefly discussing the antioxidant activity of chitosan and retrospecting the accomplishments of chitosan nanoparticles as an anticarcinogen. The various modified/functionalized/encapsulated chitosan nanoparticles and nanoforms have been listed and their biomedical deliverables presented. The anticancer accomplishments of chitosan and its modified composites have been reviewed and presented. The future of surface modified chitosan and the lacunae in the current research focus have been discussed as future perspective. This review puts forth the urge to expand the scientific curiosity towards attempting a variety of functionalization and surface modifications to chitosan. There are few well known modifications and functionalization that benefit biomedical applications that have been proven for other systems. Being a biodegradable, biocompatible polymer, chitosan-based nanomaterials are an attractive option for medical applications. Therefore, maximizing expansion of its bioactive properties are explored. The need for applying the ideal functionalization that will significantly promote the anticancer contributions of chitosan nanomaterials has also been stressed.

Strategies to improve insulin delivery through oral route: A review

Diabetes mellitus is found to be among the most suffered and lethal diseases for mankind. Diabetes mellitus type-1 is caused by the demolition of pancreatic islets responsible for the secretion of insulin. Insulin is the peptide hormone (anabolic] that regulates the metabolism of carbohydrates, fats, and proteins. Upon the breakdown of the natural process of metabolism, the condition leads to hyperglycemia (increased blood glucose levels]. Hyperglycemia demands outsourcing of insulin. The subcutaneous route was found to be the most stable route of insulin administration but faces patient compliance problems. Oral Insulin delivery systems are the patient-centered and innovative novel drug delivery system, eliminating the pain caused by the subcutaneous route of administration. Insulin comes in contact across various barriers in the gastrointestinal tract, which has been discussed in detail in this review. The review describes about the different bioengineered formulations, including microcarriers, nanocarriers, Self-Microemulsifying drug delivery systems (SMEDDs), Self-Nanoemulsifying drug delivery systems (SNEDDs), polymeric micelles, cochleates, etc. Surface modification of the carriers is also possible by developing ligand anchored bioconjugates. A study on evaluation has shown that the carrier systems facilitate drug encapsulation without tampering the properties of insulin. Carrier-mediated transport by the use of natural, semi-synthetic, and synthetic polymers have shown efficient results in drug delivery by protecting insulin from harmful environment. This makes the formulation readily acceptable for a variety of populations. The present review focuses on the properties, barriers present in the GI tract, overcome the barriers, strategies to formulate oral insulin formulation by enhancing the stability and bioavailability of insulin.

Nanomaterials for the Diagnosis and Treatment of Head and Neck Cancers: A Review

Head and neck cancer (HNC) is a category of cancers that typically arise from the nose-, mouth-, and throat-lining squamous cells. The later stage of HNC diagnosis significantly affects the patient's survival rate. This makes it mandatory to diagnose this cancer with a suitable biomarker and imaging techniques at the earlier stages of growth. There are limitations to traditional technologies for early detection of HNC. Furthermore, the use of nanocarriers for delivering chemo-, radio-, and phototherapeutic drugs represents a promising approach for improving the outcome of HNC treatments. Several studies with nanostructures focus on the development of a targeted and sustained release of anticancer molecules with reduced side effects. Besides, nanovehicles could allow co-delivering of anticancer drugs for synergistic activity to counteract chemo- or radioresistance. Additionally, a new generation of smart nanomaterials with stimuli-responsive properties have been developed to distinguish between unique tumor conditions and healthy tissue. In this light, the present article reviews the mechanisms used by different nanostructures (metallic and metal oxide nanoparticles, polymeric nanoparticles, quantum dots, liposomes, nanomicelles, etc.) to improve cancer diagnosis and treatment, provides an up-to-date picture of the state of the art in this field, and highlights the major challenges for future improvements.

An overview of gastrointestinal mucus rheology under different pH conditions and introduction to pH-dependent rheological interactions with PLGA and chitosan nanoparticles

This review discusses the physicochemical and mechanical properties of porcine gastrointestinal mucus from a rheological point of view. Considering mucus as a viscoelastic gel that functions as a biological barrier by limiting particles passage, lubricating the gastrointestinal tract, and protecting the stomach from gastric acids. The viscoelastic and protective properties of mucus are mainly produced by its mucin network, which is stabilized through electrostatic, hydrophobic and hydrogen bonding interactions. Otherwise, mucus rheology is determined by its polyanionic nature at physiological pH. At neutral pH, mucus presents a viscous behavior produced by chains crosslinking. While, at acidic pH, mucus exhibits an elastic behavior related with the extended conformation that produces mucus gelation at the stomach. Additionally, rheology studies the degree of adhesion between a polymer-mucus mixture through rheological synergism, and how it varies at different pH conditions. Finally, mucoadhesion phenomenon is exemplified with chitosan (cationic) and poly (lactic-co-glycolic) acid (anionic) polymers.

Modulating chitosan-PLGA nanoparticle properties to design a co-delivery platform for glioblastoma therapy intended for nose-to-brain route

Nose-to-brain delivery is a promising approach to target drugs into the brain, avoiding the blood-brain barrier and other drawbacks related to systemic absorption, and enabling an effective and safer treatment of diseases such as glioblastoma (GBM). Innovative materials and technologies that improve residence time in the nasal cavity and modulate biological interactions represent a great advance in this field. Mucoadhesive nanoparticles (NPs) based on poly(lactic-co-glycolic acid) (PLGA) and oligomeric chitosan (OCS) were designed as a rational strategy and potential platform to co-deliver alpha-cyano-4-hydroxycinnamic acid (CHC) and the monoclonal antibody cetuximab (CTX) into the brain, by nasal administration. The influence of formulation and process variables (O/Aq volume ratio, Pluronic concentration, PLGA concentration, and sonication time) on the properties of CHC-loaded NPs (size, zeta potential, PDI and entrapment efficiency) was investigated by a two-level full factorial design (2⁴). Round, stable nano-sized particles (213-875 nm) with high positive surface charge (+ 33.2 to + 58.9 mV) and entrapment efficiency (75.69 to 93.23%) were produced by the emulsification/evaporation technique. Optimal process conditions were rationally selected based on a set of critical NP attributes (258 nm, + 37 mV, and 88% EE) for further conjugation with CTX. The high cytotoxicity of CHC-loaded NPs and conjugated NPs was evidenced for different glioma cell lines (U251 and SW1088). A chicken chorioallantoic membrane assay highlighted the expressive antiangiogenic activity of CHC-loaded NPs, which was enhanced for conjugated NPs. The findings of this work demonstrated the potential of this nanostructured polymeric platform to become a novel therapeutic alternative for GBM treatment. Graphical abstract.

Assessment of Residual Solvent and Drug in PLGA Microspheres by Derivative Thermogravimetry

Thermogravimetry does not give specific information on residual organic solvents in polymeric matrices unless it is hyphenated with the so-called evolved gas analysis. The purpose of this study was to apply, for the first time, derivative thermogravimetry (DTG) to characterize a residual solvent and a drug in poly-d,l-lactide-co-glycolide (PLGA) microspheres. Ethyl formate, an ICH class 3 solvent, was used to encapsulate progesterone into microspheres. DTG provided a distinct peak, displaying the onset and end temperatures at which ethyl formate started to evolve from to where it completely escaped out of the microspheres. DTG also gave the area and height of the solvent peak, as well as the temperature of the highest mass change rate of the microspheres. These derivative parameters allowed for the measurement of the amount of residual ethyl formate in the microspheres. Interestingly, progesterone affected not only the residual solvent amount but also these derivative parameters. Another intriguing finding was that there was a linear relationship between progesterone content and the peak height of ethyl formate. The residual solvent data calculated by DTG were quite comparable to those measured by gas chromatography. In summary, DTG could be an efficient and practical quality control tool to evaluate residual solvents and drugs in various polymeric matrices.

Burgeoning Polymer Nano Blends for Improved Controlled Drug Release: A Review

With continual rapid developments in the biomedical field and understanding of the important mechanisms and pharmacokinetics of biological molecules, controlled drug delivery systems (CDDSs) have been at the forefront over conventional drug delivery systems. Over the past several years, scientists have placed boundless energy and time into exploiting a wide variety of excipients, particularly diverse polymers, both natural and synthetic. More recently, the development of nano polymer blends has achieved noteworthy attention due to their amazing properties, such as biocompatibility, biodegradability and more importantly, their pivotal role in controlled and sustained drug release in vitro and in vivo. These compounds come with a number of effective benefits for improving problems of targeted or controlled drug and gene delivery systems; thus, they have been extensively used in medical and pharmaceutical applications. Additionally, they are quite attractive for wound dressings, textiles, tissue engineering, and biomedical prostheses. In this sense, some important and workable natural polymers (namely, chitosan (CS), starch and cellulose) and some applicable synthetic ones (such as poly-lactic-co-glycolic acid (PLGA), poly(lactic acid) (PLA) and poly-glycolic acid (PGA)) have played an indispensable role over the last two decades for their therapeutic effects owing to their appealing and renewable biological properties. According to our data, this is the first review article highlighting CDDSs composed of diverse natural and synthetic nano biopolymers, blended for biological purposes, mostly over the past five years; other reviews have just briefly mentioned the use of such blended polymers. We, additionally, try to make comparisons between various nano blending systems in terms of improved sustained and controlled drug release behavior.

Microfluidic fabrication and characterization of Sorafenib-loaded lipid-polymer hybrid nanoparticles for controlled drug delivery

Lipid polymer hybrid nanoparticles (LPHNPs) have been merged as potential nanocarriers for treatment of cancer. In the present study, LPHNPs loaded with Sorafenib (SFN) were prepared with PLGA, Lecithin and DSPE-PEG 2000 by using the bulk nanoprecipitation and microfluidic (MF) co-flow nanoprecipitation techniques. Herein, a glass capillary microfluidic device was primed to optimize the LPHNPs and compared to the bulk nanoprecipitation method. The morphological analysis of prepared LPHNPs revealed the well-defined spherical nano-sized particles in bulk nanoprecipitation method. Whereas, core shell morphology was observed in the MF method. The formulation prepared by the MF method (MF1-MF3) indicated relatively higher % EE (95.0%, 93.8% and 88.7%) and controlled release of the SFN from the particles as compared to the LPHNPs obtained by the bulk nanoprecipitation method. However, the release of SFN from all LPHNP formulation followed Higuchi model (R² = 0.9901-0.9389) with Fickian diffusion mechanism. Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC) and powder X-rays diffraction (pXRD) studies depicted the compatibility of SFN with all the structural components. In addition, the colloidal stability, in vitro cytotoxicity and cell growth inhibition studies of LPHNPs also demonstrated stability in biological media, biocompatibility and safety with enhanced anti-proliferative effects than the free SFN in breast cancer and prostate cancer cells. In conclusion, LPHNPs provided a prospective platform for the cancer chemotherapy and substantially improved the knowledge of fabrication and optimization of the hybrid nanoparticles.

Characterization of ginsenoside compound K loaded ionically cross-linked carboxymethyl chitosan-calcium nanoparticles and its cytotoxic potential against prostate cancer cells

Backgroud

Ginsenoside compound K (GK) is a major metabolite of protopanaxadiol-type ginsenosides and has remarkable anticancer activities in vitro and in vivo. This work used an ionic cross-linking method to entrap GK within O-carboxymethyl chitosan (OCMC) nanoparticles (Nps) to form GK-loaded OCMC Nps (GK–OCMC Nps), which enhance the aqueous solubility and stability of GK.

Methods

The GK–OCMC Nps were characterized using several physicochemical techniques, including x-ray diffraction, transmission electron microscopy, zeta potential analysis, and particle size analysis via dynamic light scattering. GK was released from GK–OCMC Nps and was conducted using the dialysis bag diffusion method. The effects of GK and GK–OCMC Nps on PC3 cell viability were measured by using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Fluorescent technology based on Cy5.5-labeled probes was used to explore the cellular uptake of GK–OCMC Nps.

Results

The GK–OCMC NPs had a suitable particle size and zeta potential; they were spherical with good dispersion. In vitro drug release from GK–OCMC NPs was pH dependent. Moreover, the in vitro cytotoxicity study and cellular uptake assays indicated that the GK–OCMC Nps significantly enhanced the cytotoxicity and cellular uptake of GK toward the PC3 cells. GK–OCMC Nps also significantly promoted the activities of both caspase-3 and caspase-9.

Conclusion

GK–OCMC Nps are potential nanocarriers for delivering hydrophobic drugs, thereby enhancing water solubility and permeability and improving the antiproliferative effects of GK.

Chitosan-modified hyaluronic acid-based nanosized drug carriers

Fabrication possibilities, detailed size and structural characterization of biodegradable chitosan (Chit) polysaccharide-modified hyaluronic acid (HyA)-based colloidal carriers are demonstrated. The negatively charged and highly hydrophilic HyA polymer chains have been ionically modified by positively charged pure Chit and crosslinked Chit macromolecules at various Chit/HyA weight ratios, which resulted in the formation of carrier nanoparticles (NPs) having three different nanostructures depending on the polymer concentrations. Electrostatically-compensated Chit/HyA polymer coils with loose colloidal structure, tripolyphosphate (TPP)-crosslinked Chit-TPP/HyA NPs having interpenetrating polymer network and well-defined Chit-TPP_core-HyA_shell NPs with diameters of 100-300 nm were also prepared and were loaded with tocopherol (TCP) and cholecalciferol (D3) having Vitamin E and D activity, respectively. By using rheological, particle charge titration and conductivity studies we first confirmed that the expected 1:1 Chit/HyA monomer molar ratio is strongly influenced by the pH of the polymer solutions as well as the deacetylation degree of Chit which are crucial factors for the solubility, purity and the quality of the commercially available biocompatible Chit in aqueous medium. Encapsulation studies revealed that D3 could be better incorporated in every system, especially in Chit-TPP/HyA NPs, while for TCP the simple Chit/HyA polymer coils were the most promising carriers.

Injectable PNIPAM/Hyaluronic acid hydrogels containing multipurpose modified particles for cartilage tissue engineering: Synthesis, characterization, drug release and cell culture study

Novel injectable thermosensitive PNIPAM/hyaluronic acid hydrogels containing various amounts of chitosan-g-acrylic acid coated PLGA (ACH-PLGA) micro/nanoparticles were synthesized and designed to facilitate the regeneration of cartilage tissue. The ACH-PLGA particles were used in the hydrogels to play a triple role: first, the allyl groups on the chitosan-g-acrylic acid shell act as crosslinkers for PNIPAM and improved the mechanical properties of the hydrogel to mimic the natural cartilage tissue. Second, PLGA core acts as a carrier for the controlled release of chondrogenic small molecule melatonin. Third, they could reduce the syneresis of the thermosensitive hydrogel during gelation. The optimum hydrogel with the minimum syneresis and the maximum compression modulus was chosen for further evaluations. This hydrogel showed a great integration with the natural cartilage during the adhesion test, and also, presented an interconnected porous structure in scanning electron microscopy images. Eventually, to evaluate the cytotoxicity, mesenchymal stem cells were encapsulated inside the hydrogel. MTT and Live/Dead assay showed that the hydrogel improved the cells growth and proliferation as compared to the tissue culture polystyrene. Histological study of glycosaminoglycan (GAG) showed that melatonin treatment has the ability to increase the GAG synthesis. Overall, due to the improved mechanical properties, low syneresis, the ability of sustained drug release and also high bioactivity, this injectable hydrogel is a promising material system for cartilage tissue engineering.

Cubosomes with surface cross-linked chitosan exhibit sustained release and bioavailability enhancement for vinpocetine

Cubosomes with surface cross-linked chitosan exhibit anti-digestion effect, sustained drug release behavior, and significantly enhanced oral bioavailability of vinpocetine.

Polyelectrolyte Complex Nanoparticles Based on Methoxy Poly(Ethylene Glycol)-B-Poly (ε-Caprolactone) Carboxylates and Chitosan for Delivery of Tolbutamide

In this study, a novel chitosan (CS)-modified nanoparticles (NPs) were developed to orally deliver tolbutamide (TOL). Methoxy poly(ethylene glycol)- b-poly(ε-caprolactone) carboxylates (mPEG₂₀₀₀-b-PCL₄₀₀₀) was synthesized via an esterification reaction. CS-modified mPEG₂₀₀₀-b-PCL₄₀₀₀-COOH NPs (CS@NPs) were fabricated by injecting mPEG₂₀₀₀-b-PCL₄₀₀₀-COOH NPs suspension (1.0 mg/mL) into CS solution (1.0 mg/mL, pH 5.0). Fourier transform infrared spectroscopy (FTIR) spectra were used to confirm the obtaining of mPEG₂₀₀₀-b-PCL₄₀₀₀-COOH. Transmission electron microscope (TEM) was carried out to observe morphology of all NPs. Nano ZS90 Malvern ParticleSizer were used to monitor the size distribution of obtained NPs. Thermogravimetry analysis (TGA) was performed to investigate the thermostability of CS@NPs. In vitro TOL release profiles were carried out in pH 1.2 and 7.4 buffers. FTIR spectra confirmed the obtaining of mPEG₂₀₀₀-b-PCL₄₀₀₀-COOH. TGA curves indicated that the protection of CS shells improved the thermostability of mPEG₂₀₀₀-b-PCL₄₀₀₀-COOH NPs. Cell tests indicated the CS@NPs had no obvious cytotoxicity, and they were easily taken up by 293T cells. In vitro release profiles showed that 91.0 ± 1.9% of encapsulated TOL were released from TOL-CS@NPs in pH 7.4 buffer. Therefore, the positive potential of CS@NPs could increase their combining capacity with intestinal mucosal cells. Finally, these NPs would improve the bioavailability of hydrophobic drugs.

Insulin-loaded hydroxypropyl methyl cellulose-co-polyacrylamide-co-methacrylic acid hydrogels used as rectal suppositories to regulate the blood glucose of diabetic rats

The purpose of this study was developing a novel hydroxypropyl methyl cellulose-co-polyacrylamide-co-methacrylic acid (HPMC-co-PAM-co-PMAA) hydrogel, which was used as rectal suppository to regulate the blood glucose of diabetes. HPMC-co-PAM-co-PMAA hydrogel was fabricated via free-radical polymerization. Fourier transform infrared spectroscopy (FTIR) and Raman spectra were used to confirm the fabrication of HPMC-co-PAM-co-PMAA hydrogel. Their inner morphology was observed with scanning electron microscope (SEM). The extracts of hydrogel were applied to study their cell viability. The hypoglycemic effects of insulin (INS)-loaded HPMC-co-PAM-co-PMAA hydrogels were investigated by rectal administration. FTIR and Raman spectra confirmed the obtaining of HPMC-co-PAM-co-PMAA hydrogels. Many micro-pores were found in the SEM photograph of HPMC-co-PAM-co-PMAA hydrogels. Cell experiments indicated that HPMC-co-PAM-co-PMAA hydrogel was out of cytotoxicity. In vitro release profiles showed that INS-loaded hydrogel could release INS at a continuous manner in pH 7.4 buffer (rectal conditions). Animal experiments suggested that INS-loaded hydrogel had an obvious hypoglycemic effect. Therefore, as a convenient and economic method of administration, INS-loaded HPMC-co-PAM-co-PMAA hydrogels could be used as rectal suppositories to regulate blood glucose.

Methylcellulose and polyacrylate binary hydrogels used as rectal suppository to prevent type I diabetes

The purpose of this study was to fabricate a novel binary hydrogel, and the insulin-loaded hydrogel was used as rectal suppository to prevent type I diabetes. The binary hydrogel was synthesized via solution polymerization. Its structure was studied by Fourier transform infrared spectroscopy (FTIR) and Raman spectra. The swelling behaviors of binary hydrogels were revealed in pH 1.2, 6.8 and 7.4 buffers, respectively. Their inner morphologies were observed with a scanning electron microscope (SEM). Insulin (INS) was selected as a model drug and encapsulated into the binary hydrogels. INS release study was carried out in pH 7.4 buffer. The hypoglycemic effects of INS-loaded hydrogels were studied by rectal administration. FTIR and Raman spectra confirmed the obtaining of binary hydrogels. The hydrogel showed a high swelling ratio in pH 7.4 (rectum environment). SEM photographs illustrated that many micro-pores in the inner of binary hydrogels, which could accommodate abundant guest molecule (e.g. INS). INS release profile suggested that INS-loaded hydrogels could diffuse INS at a sustained manner. Animal studies proved that INS-loaded binary hydrogel had an obvious hypoglycemic effect. Therefore, it could be speculated that the binary hydrogel had a potential application on treating type I diabetes by rectal administration.

Enhanced cytotoxic and apoptotic potential in hepatic carcinoma cells of chitosan nanoparticles loaded with ginsenoside compound K

Ginsenoside compound K (CK) has been shown to exhibit anticancer properties. In this study, chitosan nanoparticles loaded with ginsenoside compound K (CK-NPs) were prepared as a delivery system using a self-assembly technique with amphipathic deoxycholic acid-O carboxymethyl chitosan as the carrier, which improved the water solubility of CK. By evaluating drug loading, entrapment efficiency, and in vitro release behavior, the feasibility of CK-NPs as a drug carrier nanoparticle for the treatment of human hepatic carcinoma cells (HepG2) was investigated. Result revealed that CK and CK-NPs showed a dose-dependent inhibitory effect on HepG2 cells with IC₅₀ values of 23.33 and 16.58 μg/mL, respectively. Furthermore, fluorescence imaging demonstrated that CK-NPs promoted cellular uptake in vitro. Therefore, all results indicated that CK-NPs might be a novel drug delivery system to improve the solubility and enhance the cytotoxic and apoptotic potentials of CK for effective liver cancer chemotherapy.

An Overview of Chitosan Nanoparticles and Its Application in Non-Parenteral Drug Delivery

The focus of this review is to provide an overview of the chitosan based nanoparticles for various non-parenteral applications and also to put a spotlight on current research including sustained release and mucoadhesive chitosan dosage forms. Chitosan is a biodegradable, biocompatible polymer regarded as safe for human dietary use and approved for wound dressing applications. Chitosan has been used as a carrier in polymeric nanoparticles for drug delivery through various routes of administration. Chitosan has chemical functional groups that can be modified to achieve specific goals, making it a polymer with a tremendous range of potential applications. Nanoparticles (NP) prepared with chitosan and chitosan derivatives typically possess a positive surface charge and mucoadhesive properties such that can adhere to mucus membranes and release the drug payload in a sustained release manner. Chitosan-based NP have various applications in non-parenteral drug delivery for the treatment of cancer, gastrointestinal diseases, pulmonary diseases, drug delivery to the brain and ocular infections which will be exemplified in this review. Chitosan shows low toxicity both in vitro and some in vivo models. This review explores recent research on chitosan based NP for non-parenteral drug delivery, chitosan properties, modification, toxicity, pharmacokinetics and preclinical studies.