Preparation and characterization of folic acid linked poly(L-glutamate) nanoparticles for cancer targeting

Advances in Nanotechnology for Enhancing the Solubility and Bioavailability of Poorly Soluble Drugs

This manuscript offers a comprehensive overview of nanotechnology's impact on the solubility and bioavailability of poorly soluble drugs, with a focus on BCS Class II and IV drugs. We explore various nanoscale drug delivery systems (NDDSs), including lipid-based, polymer-based, nanoemulsions, nanogels, and inorganic carriers. These systems offer improved drug efficacy, targeting, and reduced side effects. Emphasizing the crucial role of nanoparticle size and surface modifications, the review discusses the advancements in NDDSs for enhanced therapeutic outcomes. Challenges such as production cost and safety are acknowledged, yet the potential of NDDSs in transforming drug delivery methods is highlighted. This contribution underscores the importance of nanotechnology in pharmaceutical engineering, suggesting it as a significant advancement for medical applications and patient care.

Covalently Functionalized Egyptian Blue Nanosheets for Near-Infrared Bioimaging

Fluorophores emitting in the near-infrared (NIR) wavelength region present optimal characteristics for photonics and especially bioimaging. Unfortunately, only few NIR fluorescent materials are known, and even fewer are biocompatible. For this reason, the scientific interest in designing NIR fluorophores is very high. Egyptian Blue (CaCuSi₄O₁₀, EB) is an NIR fluorescent layered silicate that can be exfoliated into fluorescent nanosheets (EB-NS). So far, its surface chemistry has not been tailored, but this is crucial for colloidal stability and biological targeting. Here, we demonstrate covalent surface functionalization of EB nanosheets (EBfunc) via Si-H activation using hydrosilanes with variable functionalities. In the first part of this work, EB-NS are grafted with the visible fluorescent pyrene (Pyr) moieties to demonstrate conjugation by colocalization of the Vis/NIR fluorescence on the (single) EB-NS level. Next, the same grafting procedure was repeated and validated with carboxyl group (COOH)-containing hydrosilanes. These groups serve as a generic handle for further (bio)functionalization of the EB-NS surface. In this way, folic acid (FA) could be conjugated to EB-NS, allowing the targeting of folic acid receptor-expressing cancer cells. These results highlight the potential of this surface chemistry approach to modify EB-NS, enabling targeted NIR imaging for biomedical applications.

Dual targeting nanoparticles based on hyaluronic and folic acids as a promising delivery system of the encapsulated 4-Methylumbelliferone (4-MU) against invasiveness of lung cancer in vivo and in vitro

Lung cancer is the most common cause of cancer death worldwide. Thereby, new treatment strategies as targeting nano-therapy present promising possibilities to control the aggressiveness of lung cancer. Dual CD44 and folate receptors targetable nanocapsule based on folic-polyethylene glycol-hyaluronic (FA-PEG-HA) were fabricated to improve the therapeutic activity of 4-Methylumbelliferone (4-MU) toward lung cancer. In this study, we fabricate 4-MU Nps as a hybrid polymeric (protamine) protein (albumin) nanocapsule, then functionalized by targeting layer to form 4-MU@FA-PEG-HA Nps with encapsulation efficacy 96.15%. The in vitro study of free 4-MU, 4-MU Nps and 4-MU@FA-PEG-HA Nps on A549 lung cancer cells reveal that the 4-MU Nps and 4-MU@FA-PEG-HA Nps were more cytotoxic than free 4-MU on A549 cells. The observed therapeutic activity of 4-MU@FA-PEG-HA Nps on urethane-induced lung cancer model, potentiality revealed a tumor growth inhibition via apoptotic mechanisms and angiogenesis inhibition. The results were supported by Enzyme-linked immunosorbent assay (ELIZA) of transforming growth factors (TGFβ1) and serum HA, histopathological analysis as well as immunohistochemical Ki67, CD44, Bcl-2 and caspace-3 staining. Moreover, 4-MU@FA-PEG-HA Nps exhibited a promising safety profile. Hence, it is expected that our developed novel nano-system can be used for potential application on tumor therapy for lung cancer.

In vitro and in vivo characteristics of doxorubicin-loaded cyclodextrine-based polyester modified gadolinium oxide nanoparticles: a versatile targeted theranostic system for tumour chemotherapy and molecular resonance imaging

β-Cyclodextrine-based polyester was coated on the surface of gadolinium oxide nanoparticles (NPs) and then functionalised with folic acid to produce an efficient pH-sensitive targeted theranostic system (Gd₂O₃@PCD-FA) for doxorubicin delivery and magnetic resonance imaging (MRI). Gd₂O₃@PCD-FA was fully characterised by FTIR, vibrating sample magnetometer, TGA, XRD, SEM and TEM analyses. The dissolution profile of DOX showed a pH sensitive release. No significant toxicity was observed for the targeted NPs (Gd₂O₃@PCD-FA) and DOX-loaded NPs inhibiting M109 cells viability more efficiently than free DOX. Moreover, the negligible hemolytic activity of the targeted NPs showed their appropriate hemocompatibility. The preferential uptake was observed for the developed Gd₂O₃@PCD-FA-DOX NPs in comparison with Dotarem using T₁- and T₂-weighted MRI in the presence of folate receptor-positive and folate receptor-negative cancer cells (M109 and 4T1, respectively). Furthermore, in vivo studies revealed that Gd₂O₃@PCD-FA-DOX not only exhibited considerably relaxivity performance as a contrast agent for MRI, but also improved in vivo anti-tumour efficacy of the system. The results suggest that Gd₂O₃@PCD-FA-DOX improves its therapeutic efficacy in the treatment of solid tumours and also reduces the adverse effects, so it could be proposed as a promising drug delivery system for chemotherapy and molecular imaging diagnosis in MRI.

Gadolinium (III) oxide nanoparticles coated with folic acid-functionalized poly(β-cyclodextrin-co-pentetic acid) as a biocompatible targeted nano-contrast agent for cancer diagnostic: in vitro and in vivo studies

OBJECTIVES

In this study, a novel targeted MRI contrast agent was developed by coating gadolinium oxide nanoparticles (Gd₂O₃ NPs) with β-cyclodextrin (CD)-based polyester and targeted by folic acid (FA).

MATERIALS AND METHODS

The developed Gd₂O₃@PCD-FA MRI contrast agent was characterized and evaluated in relaxivity, in vitro cell targeting, cell toxicity, blood compatibility and in vivo tumor MR contrast enhancement.

RESULTS

In vitro cytotoxicity and hemolysis assays revealed that Gd₂O₃@PCD-FA NPs have no significant cytotoxicity after 24 and 48 h against normal human breast cell line (MCF-10A) at concentration of up to 50 µg Gd⁺³/mL and have high blood compatibility at concentration of up to 500 µg Gd⁺³/mL. In vitro MR imaging experiments showed that Gd₂O₃@PCD-FA NPs enable targeted contrast T₁- and T₂-weighted MR imaging of M109 as overexpressing folate receptor cells. Besides, the in vivo analysis indicated that the maximum contrast-to-noise ratio (CNR) of tumor in mice increased after injection of Gd₂O₃@PCD-FA up to 5.89 ± 1.3 within 1 h under T₁-weighted imaging mode and reduced to 1.45 ± 0.44 after 12 h. While CNR increased up to maximum value of 1.98 ± 0.28 after injection of Gd₂O₃@PCD within 6 h and reduced to 1.12 ± 0.13 within 12 h.

CONCLUSION

The results indicate the potential of Gd₂O₃@PCD-FA to serve as a novel targeted nano-contrast agent in MRI.

Hybrid polymeric-protein nano-carriers (HPPNC) for targeted delivery of TGFβ inhibitors to hepatocellular carcinoma cells

TGFβ1 pathway antagonists have been considered promising therapies to attenuate TGFβ downstream signals in cancer cells. Inhibiting peptides, as P-17 in this study, are bound to either TGFβ1 or its receptors, blocking signal transduction. However, for efficient use of these TGFβ1antagonist as target therapeutic tools, improvement in their delivery is required. Here, a plasmid carrying specific shDNA (SHT-DNA), small interfering RNA (siRNA), and the peptide (P-17) were loaded separately into folic acid (FA)-functionalized nano-carriers made of Bovine Serum Albumin (BSA). The two building blocks of the carrier, (BSA and FA) were used because of the high affinity of albumin for liver and for the overexpression of folate receptors on the membrane of hepatocellular carcinoma cells. The empty and the encapsulated carriers were thoroughly investigated to characterize their structure, to evaluate the colloidal stability and the surface functionalization. The entrapment of SHT-DNA, siRNA and P-17, respectively, was demonstrated by morphological and quantitative analysis. Finally, cellular studies were performed to assess the targeting efficiency of the hybrid carriers. These vectors were used because of the high affinity of albumin for liver and for the overexpression of folate receptors on the membrane hepatocellular carcinoma cells. The empty and the encapsulated carriers were thoroughly investigated to characterize their structure, to evaluate the colloidal stability and the surface functionalization. The entrapment of SHT-DNA, siRNA and P-17, respectively, was demonstrated by morphological and quantitative analysis. A novel fabrication of Hybrid Polymeric-Protein Nano-Carriers (HPPNC) for delivering TGF β1 inhibitors to HCC cells has been developed. SHT-DNA, siRNA and P-17 have been successfully encapsulated. TGF β1 inhibitors-loaded HPPNC were efficiently uptaken by HLF cells.

A novel nanohybrid for cancer theranostics: folate sensitized Fe2O3 nanoparticles for colorectal cancer diagnosis and photodynamic therapy

Organic-inorganic nanohybrids are becoming popular for their potential biological applications, including diagnosis and treatment of cancerous cells. The motive of this study is to synthesise a nanohybrid for the diagnosis and therapy of colorectal cancer. Here we have developed a facile and cost-effective synthesis of folic acid (FA) templated Fe₂O₃ nanoparticles with excellent colloidal stability in water using a hydrothermal method for the theranostics applications. The attachment of FA to Fe₂O₃ was confirmed using various spectroscopic techniques including FTIR and picosecond resolved fluorescence studies. The nanohybrid (FA-Fe₂O₃) is a combination of two nontoxic ingredients FA and Fe₂O₃, showing remarkable photodynamic therapeutic (PDT) activity in human colorectal carcinoma cell lines (HCT 116) via generation of intracellular ROS. The light induced enhanced ROS activity of the nanohybrid causes significant nuclear DNA damage, as confirmed from the comet assay. Assessment of p53, Bax, Bcl2, cytochrome c (cyt c) protein expression and caspase 9/3 activity provides vivid evidence for cell death via an apoptotic pathway. In vitro magnetic resonance imaging (MRI) experiments in folate receptor (FR) overexpressed cancer cells (HCT 116) and FR deficient human embryonic kidney cells (HEK 293) reveal the target specificity of the nanohybrid towards cancer cells, and are thus pronounced MRI contrasting agents for the diagnosis of colorectal cancer.

Oxaprozin-Loaded Lipid Nanoparticles towards Overcoming NSAIDs Side-Effects

PURPOSE

Nanostructured Lipid Carriers (NLCs) loading oxaprozin were developed to address an effective drug packaging and targeted delivery, improving the drug pharmacokinetics and pharmacodynamics properties and avoiding the local gastric side-effects. Macrophages actively phagocyte particles with sizes larger than 200 nm and, when activated, over-express folate beta receptors - features that in the case of this work constitute the basis for passive and active targeting strategies.

METHODS

Two formulations containing oxaprozin were developed: NLCs with and without folate functionalization. In order to target the macrophages folate receptors, a DSPE-PEG2000-FA conjugate was synthesized and added to the NLCs.

RESULTS

These formulations presented a relatively low polydispersity index (approximately 0.2) with mean diameters greater than 200 nm and zeta potential inferior to -40 mV. The encapsulation efficiency of the particles was superior to 95% and the loading capacity was of 9%, approximately. The formulations retained the oxaprozin release in simulated gastric fluid (only around 10%) promoting its release on simulated intestinal fluid. MTT and LDH assays revealed that the formulations only presented cytotoxicity in Caco-2 cells for oxaprozin concentrations superior to 100 μM. Permeability studies in Caco-2 cells shown that oxaprozin encapsulation did not interfered with oxaprozin permeability (around 0.8 × 10(-5) cm/s in simulated intestinal fluid and about 1.45 × 10(-5) cm/s in PBS). Moreover, in RAW 264.7 cells NLCs functionalization promoted an increased uptake over time mainly mediated by a caveolae uptake mechanism.

CONCLUSIONS

The developed nanoparticles enclose a great potential for oxaprozin oral administration with significant less gastric side-effects.

Exploring a new SPION-based MRI contrast agent with excellent water-dispersibility, high specificity to cancer cells and strong MR imaging efficacy

Advances in contrast agents have greatly enhanced the sensitivity of magnetic resonance imaging (MRI) technique for early diagnosis of cancer. However, the commercial superparamagnetic iron oxide nanoparticles (SPION)-based contrast agents synthesized by co-precipitation method are not monodisperse with irregular morphologies and ununiform sizes. Other reported SPION-based contrast agents synthesized by solvothermal method or thermal decomposition method are limited by the bad water-dispersibility and low specificity to cancer cells. Herein, we propose a new strategy for exploring SPION-based MRI contrast agents with excellent water-dispersibility and high specificity to cancer cells. The SPION was synthesized by a polyol method and then entrapped into albumin nanospheres (AN). After that, a ligand folic acid (FA) was conjugated onto the surface of the AN to construct a SPION-AN-FA composite. The transmission electron microscope (TEM) and dynamic light scattering (DLS) results indicate that the SPION-AN-FA has a spherical shape, a uniform size and an excellent water-dispersibility (polydispersity index (PDI) <0.05). The results of laser scanning confocal microscope (LSCM) and flow cytometry demonstrate that the SPION-AN-FA nanoparticles are highly specific to MCF-7 and SPC-A-1 cells due to the recognition of ligand FA and folate receptor α (FRα). The r2/r1 value of SPION-AN-FA is around 40, which is much higher than that of Resovist(®) indicating that our SPION-AN-FA has a stronger T2 shortening effect. The T2-weighted images of MCF-7 cells incubated with SPION-AN-FA are significantly darker than those of MCF-7 cells incubated with AN, indicating that our SPION-AN-FA has a strong MR imaging efficacy. In view of the excellent water-dispersibility, the high specificity to cancer cells and the strong MR imaging efficacy, our SPION-AN-FA can be used as a negative MR contrast agent.

Targeted poly (L-γ-glutamyl glutamine) nanoparticles of docetaxel against folate over-expressed breast cancer cells

A novel folate (FA) conjugated poly(l-γ-glutamyl glutamine) (PGG) nanoparticle loaded with docetaxel (DTX) was prepared to take advantage of both targeted drug delivery in breast cancer and reducing the overall side effects due to the adjuvant free formulation in comparison with Taxotere(®). Nanoprecipitation method was employed to prepare nanoparticles (NPs). The chemical structure of PGG synthesized polymers and PGG-FA conjugates and polymeric nanoparticles were characterized by H NMR, FTIR spectroscopy, field emission scanning electron microscopy, and laser scanning confocal microscopy. The average size of optimized nanoparticles with the aid of Box-Behnken experimental design was 131.96 ± 5.34(nm) with polydispersity of 0.089 ± 0.019, zeta potential of -25.8 ± 2.21(mV), and entrapment efficiency of 67.83 ± 3.29(%). In vitro cytotoxicity of the designed NPs was investigated by MTT assay against three chosen cell lines of MCF7, 4T1, and A549 based on their folate receptor expression capacity and was compared with Taxotere(®). Moreover, PGG-FOL NPs were loaded with 6-coumarin for cellular uptake investigation. In order to assess the antitumor efficacy and biodistribution of targeted NPs, 4T1 murine breast tumors were established on the balb/c mice and in vivo studies were performed. The obtained results showed that the novel designed system was highly effective against tumor cells and successfully localized in the tumor site.

Multifunctional nanoparticles of biodegradable copolymer blend for cancer diagnosis and treatment

AIMS

A multifunctional nanoparticle (NP) system is developed to provide a sustained, controlled and targeted co-delivery of quantum dots (QDs) as a model imaging agent and docetaxel as a model anticancer drug. The NPs are made of a polymeric blend of poly(lactic-co-glycolic acid), which forms a biodegradable NP matrix, and the novel copolymer D-alpha-tocopheryl polyethylene glycol 1000 succinate-COOH, which facilitates ligand conjugation on the NP surface.

MATERIALS & METHODS

The NPs were prepared by nanoprecipitation and characterized for their size and size distribution, surface morphology, surface charge, QD/drug encapsulation and loading efficiency, and in vitro drug release profile. The targeting effects of such NPs were evaluated both quantitatively and qualitatively through the cellular uptake of the QDs as well as the cytotoxicity of the drug using MCF-7 cells, which overexpress folate receptors and NIH 3T3 cells, which have no folate receptors overexpression.

RESULTS & CONCLUSIONS

NPs with folate conjugated on their surface achieved much higher cellular uptake than those with no folate conjugation in MCF-7 cells while no significant targeting effect could be observed for NIH 3T3 cells. The drug formulated in the folate-conjugated NPs were more efficious compared with NPs with no folate conjugation as well as the current clinical formulation Taxotere.

Ternary biomolecular nanoparticles for targeting of cancer cells and anti-angiogenesis

To develop a targeted drug delivery system for cancer therapy and anti-angiogenesis, amphiphilic heparin bioconjugates were synthesized by chemical conjugation of hydrophobic retinoic acid and a targeting ligand, folic acid, to the heparin backbone (HFR). The chemical structure of the HFR conjugates was confirmed by proton nuclear magnetic resonance ((1)H NMR). Various HFR conjugates with different retinoic acid coupling ratios were obtained by modulating the retinoic acid feed molar ratio. The anticoagulant activity of the HFR conjugates decreased to 30% of heparin levels as measured by anti-FXa chromogenic assay. The bioconjugates retained the anti-angiogenic effect, showing a significant decrease in endothelial tubular formation using a Matrigel model. In aqueous solutions, the bioconjugates readily self-assembled to form nanoparticles via the hydrophobic interaction among retinoic acid. The HFR nanoparticles were spherical and ranged from 150 to 300 nm, depending on the degree of retinoic acid coupling. The presence of folic acid efficiently enhanced the cellular uptake of the HFR nanoparticles in folate receptor-positive cells. Furthermore, the internalized HFR nanoparticles demonstrated greater cytotoxicity against folate receptor-positive cells compared to free retinoic acid. These results indicate that specific delivery of retinoic acid with ternary biomolecular nanoparticles targeting folate receptor-positive tumors is a promising strategy to enhance chemotherapy efficacy with minimal side effects.

Design, synthesis and applications of hyaluronic acid-paclitaxel bioconjugates

Paclitaxel (1a), a well known antitumor agent adopted mainly for the treatment of breast and ovarian cancer, suffers from significant disadvantages such as low solubility, certain toxicity and specific drug-resistance of some tumor cells. To overcome these problems extensive research has been carried out. Among the various proposed strategies, the conjugation of paclitaxel (1a) to a biocompatible polymer, such as hyaluronic acid (HA, 2), has also been considered. Coupling a bioactive compound to a biocompatible polymer offers, in general, many advantages such as better drug solubilization, better stabilization, specific localization and controlled release. Hereafter the design, synthesis and applications of hyaluronic acid-paclitaxel bioconjugates are reviewed. An overview of HA-paclitaxel combinations is also given.