Manipulation of pH-Sensitive interactions between podophyllotoxin-chitosan for enhanced controlled drug release

Acid-triggered rattan ball-like β-glucan carrier embedding doxorubicin to synergistically alleviate precancerous lesions of gastric cancer via p53 and PI3K pathways

The early intervention of precancerous lesions of gastric cancer (PLGC) is crucial for improving the survival of patients with gastric cancer. Traditional pharmaceuticals for the treatment of PLGC are limited by side effects, thus developing innovative drug carrier that are more efficient but without the undesirable side effects is required. Here, we proposed an acid-triggered mushroom-derived β-glucan carrier embedding doxorubicin (DOX) to circumvent drug cytotoxicity and synergistically alleviate PLGC based on the controlled conformational transformation. The triple helix β-glucan extracted from Dictyophora rubrovolvata (DRP) loaded doxorubicin driven by pH and DMSO regulation, forming two rattan ball-like nanoparticles (DRP-DOX(pH) and DRP-DOX(DMSO)) via its collapse and recombination of triple-helix conformation. The findings revealed that DRP-DOXs achieved acid-triggerable and sustained drug delivery with an average particle size of 500 nm and 550 nm. In vitro evaluation of GES-1 cells showed DRP-DOXs reduced reactive oxygen species (ROS) production and altered mitochondrial membrane potential. Compared to DRP-DOX(DMSO) and DRP, DRP-DOX(pH) could more effectively downregulate cellular oxidative stress and inflammation to eventually alleviate PLGC, by regulating the p53 and PI3K pathways to mitigate gastric mucosa damage. Consequently, the nature-derived β-glucan delivery nanovesicle holds great promising applications in reducing drug toxicity and suppressing the development of PLGC.

Chitosan hydrogels enriched with bioactive phloroglucinol for controlled drug diffusion and potential wound healing

We report a facile strategy to prepare chitosan (CS) hydrogels that eliminates the need for chemical crosslinking for advanced biomedical therapies. This approach gives controlled properties to the hydrogels by incorporating a natural bioactive phenolic compound, phloroglucinol (PG), into their microstructure. The adsorption of PG onto CS chains enhanced the hydrogels' antioxidant activity by up to 25 % and resulted in a denser, more entangled structure, reducing the pore size by 59 μm while maintaining porosity above 94 %. This allowed us to finely adjust pore size and swelling capacity. These structural properties make these hydrogels well-suited for wound healing dressings, promoting fibroblast proliferation and exhibiting excellent hemocompatibility. Furthermore, to ensure the versatility of these hydrogels, herein, we demonstrate their potential as drug delivery systems, particularly for dermal infections. The drug release can be controlled by a combination of drug diffusion through the swollen hydrogel and relaxation of the CS chains. In summary, our hydrogels leverage the synergistic effects of CS's antibacterial and antifungal properties with PG's antimicrobial and anti-inflammatory attributes, positioning them as promising candidates for biomedical and pharmaceutical applications, more specifically in advanced wound healing therapies with local drug delivery.

A pH-responsive bi-MIL-88B MOF coated with folic acid-conjugated chitosan as a promising nanocarrier for targeted drug delivery of 5-Fluorouracil

Cancer has remained one of the leading causes of death worldwide, with a lack of effective treatment. The intrinsic shortcomings of conventional therapeutics regarding tumor specificity and non-specific toxicity prompt us to look for alternative therapeutics to mitigate these limitations. In this regard, we developed multifunctional bimetallic (FeCo) bi-MIL-88B-FC MOFs modified with folic acid-conjugated chitosan (FC) as drug delivery systems (DDS) for targeted delivery of 5-Fluorouracil (5-FU). The bi-MIL-88B nanocarriers were characterized through various techniques, including powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray, thermogravimetric analysis, and Fourier transform infrared spectroscopy. Interestingly, 5-FU@bi-MIL-88B-FC showed slower release of 5-FU due to a gated effect phenomenon endowed by FC surface coating compared to un-modified 5-FU@bi-MIL-88B. The pH-responsive drug release was observed, with 58% of the loaded 5-FU released in cancer cells mimicking pH (5.2) compared to only 24.9% released under physiological pH (5.4). The in vitro cytotoxicity and cellular internalization experiments revealed the superiority of 5-FU@bi-MIL-88B-FC as a highly potent targeted DDS against folate receptor (FR) positive SW480 cancer cells. Moreover, due to the presence of Fe and Co in the structure, bi-MIL-88B exhibited peroxidase-like activity for chemodynamic therapy. Based on the results, 5-FU@bi-MIL-88B-FC could serve as promising candidate for smart DDS by sustained drug release and selective targeting.

Podophyllotoxin and its derivatives: Potential anticancer agents of natural origin in cancer chemotherapy

The use of plant secondary metabolites has gained considerable attention among clinicians in the prevention and treatment of cancer. A secondary metabolite isolated mainly from the roots and rhizomes of Podophyllum species (Berberidaceae) is aryltetralin lignan - podophyllotoxin (PTOX). The purpose of this review is to discuss the therapeutic properties of PTOX as an important anticancer compound of natural origin. The relevant information regarding the antitumor mechanisms of podophyllotoxin and its derivatives were collected and analyzed from scientific databases. The results of the analysis showed PTOX exhibits potent cytotoxic activity; however, it cannot be used in its pure form due to its toxicity and generation of many side effects. Therefore, it practically remains clinically unusable. Currently, high effort is focused on attempts to synthesize analogs of PTOX that have better properties for therapeutic use e.g. etoposide (VP-16), teniposide, etopophos. PTOX derivatives are used as anticancer drugs which are showing additional immunosuppressive, antiviral, antioxidant, hypolipemic, and anti-inflammatory effects. In this review, attention is paid to the high potential of the usefulness of in vitro cultures of P. peltatum which can be a valuable source of lignans, including PTOX. In conclusion, the preclinical pharmacological studies in vitro and in vivo confirm the anticancer and chemotherapeutic potential of PTOX and its derivatives. In the future, clinical studies on human subjects are needed to certify the antitumor effects and the anticancer mechanisms to be certified and analyzed in more detail and to validate the experimental pharmacological preclinical studies.

Targeted PEGylated Chitosan Nano-complex for Delivery of Sodium Butyrate to Prostate Cancer: An In Vitro Study

Introduction: Cancer remains a challenging issue against human health throughout the world; As a result, introducing novel approaches would be beneficial for cancer treatment. In this research, sodium butyrate (Sb) is one of the effective anti-cancer therapeutics (also a potent survival factor for normal cells) that was used for prostate cancer suppression in the platform of modified chitosan (CS) nano-complex (polyethylene glycol (PEG)-folic acid (FA)-Sb-CS). Methods: Different analytical devices including Fourier transform infrared, dynamic light scattering, high-performance liquid chromatography, scanning electron microscopy, and transmission electron microscopy were applied for the characterization of synthetics. On the other hand, biomedical tests including cell viability assay, molecular and functional assay of apoptosis/autophagy pathways, and cell cycle arrest analysis were potentially implemented on human PC3 (folate receptor-negative prostate cancer) and DU145 (folate receptor-positive prostate cancer) and HFF-1 normal cell lines. Results: The quality of the syntheses was effectively verified, and the size range from 140 to 170 nm was determined for the PEG-CS-FA-Sb sample. Also, 75  ±  5% of drug entrapment efficiency with controlled drug release manner (Sb release of 54.21% and 74.04% for pHs 7.4 and 5.0) were determined for nano-complex. Based on MTT results, PEG-CS-FA-Sb has indicated 72.07% and 33.53% cell viability after 24 h of treatment with 9 mM on PC3 and DU145 cell lines, respectively, which is desirable anti-cancer performance. The apoptotic and autophagy genes overexpression was 15-fold (caspase9), 2.5-fold (BAX), 11-fold (ATG5), 2-fold (BECLIN1), and 3-fold (mTORC1) genes in DU145 cancer cells. More than 50% of cell cycle arrest and 45.05% of apoptosis were obtained for DU145 cancer cells after treatment with nano-complex. Conclusion: Hence, the synthesized Sb-loaded nano-complex could specifically suppress prostate cancer cell growth and induce apoptosis and autophagy in the molecular and cellular phases.

Recent advances in targeted gene silencing and cancer therapy by nanoparticle-based delivery systems

Nanomedicine has emerged as a promising platform for disease treatment and much progress has been achieved in the clinical translation for cancer treatment. Several types of nanomedicines have been approved for therapeutic application. However, many nanoparticles still suffer from challenges in the translation from bench to bedside. Currently, nanoparticle-based delivery systems have been developed to explore their functions in targeted gene silencing and cancer therapy. This review describes the research progress of different nano-carriers in targeted gene editing, and the recent progress in co-delivery of anticancer drugs and small ribonucleic acid. We also summarize the strategies for improving the specificity of carrier systems. Finally, we discuss the functions of targeted nano-carriers in overcoming chemotherapeutic drug resistance in cancer therapy. As research continues to advance, a better understanding of the safety including long-term toxicity, immunogenicity, and body metabolism may impel nanoparticle translation.

Impact of metallic coating on the retention of 225Ac and its daugthers within core-shell nanocarriers

Currently, alpha-emitting radionuclide 225Ac is one of the most promising isotopes in alpha therapy due to its high linear energy transfer during four sequential alpha decays. However, the main obstacle preventing the full introduction of 225Ac into clinical practice is the lack of stable retention of radionuclides, leading to free circulation of toxic isotopes in the body. In this work, the surface of silica nanoparticles (SiO2 NPs) has been modified with metallic shells composed of titanium dioxide (TiO2) and gold (Au) nanostructures to improve the retention of 225Ac and its decay products within the developed nanocarriers. In vitro and in vivo studies in healthy mice show that the metallic surface coating of SiO2 NPs promotes an enhanced sequestering of radionuclides (225Ac and its daughter isotopes) compared to non-modified SiO2 NPs for a prolonged period of time. Histological analysis reveals that for the period of 3-10 d after the injections, the developed nanocarriers have no significant toxic effects in mice. At the same time, almost no accumulation of leaked radionuclides can be detected in non-target organs (e.g., in the kidneys). In contrast, non-modified carriers (SiO2 NPs) demonstrate the release of free radionuclides, which are distributed over the whole animal body with the consequent morphological changes in the lung, liver and kidney tissues. These results highlight the potential of the developed nanocarriers to be utilized as radionuclide delivery systems and offer an insight into design rules for the fabrication of new nanotherapeutic agents.

Synthesis, characterization and application of chitosan-N-(4-hydroxyphenyl)-methacrylamide derivative as a drug and gene carrier

The aim of this study was to develop a green method to fabricate a novel CS modified N-(4-hydroxyphenyl)- methacrylamide conjugate (CSNHMA) and to evaluate its biomedical potential. CSNHMA has been prepared by a simple method via aza Michael addition reaction between CS and N- (4-hydroxyphenyl)-methacrylamide (NHMA) in ethanol. Its structural and morphological properties were characterized by various analysis techniques. The obtained results confirmed that a highly porous network structure of CSNHMA was successfully synthesized via aza Michael addition reaction. Consequently, it was analyzed as a drug and gene carrier. CSNHMA/pGL3 showed an enhanced buffering capacity due to the presence of NHMA moiety leading to higher transfection efficiency in all cancer cells (A549, HeLa and HepG2) as compared to native CS and Lipofectamine®. Therefore, these findings clearly support the possibility of using CSNHMA as a good transfection agent. For in vitro drug release study, we prepared CSNHMA nanoparticles (NPs) and curcumin loaded CSNHMA NPs of size <230 nm respectively via the non-toxic ionic gelation route and the encapsulation efficiency of drug was found to be 77.03%. In vitro drug release studies demonstrated a faster and sustained release of curcumin loaded CSNHMA NPs at pH 5.0 compared to physiological pH.

Chitosan-tripolyphosphate nanoparticles designed to encapsulate polyphenolic compounds for biomedical and pharmaceutical applications - A review

Plant-based polyphenols are natural compounds, present in fruits and vegetables. During recent years, polyphenols have gained special attention due to their nutraceutical and pharmacological activities for the prevention and treatment of human diseases. Nevertheless, their photosensitivity and low bioavailability, rapid metabolism and short biological half-life represent the major limitations for their use, which could be overcome by polyphenols encapsulation (flavonoids and non-flavonoids) into chitosan (CS)-tripolyphosphate (TPP) based nanoparticles (NP). In this review, we particularly focused on the ionic gelation method for the NP design. This contribution exhaustively discusses and compares results of scientific reports published in the last decade referring to ionic gelation applied for the protection, controlled and site-directed delivery of polyphenols. As a consequence, CS-TPP NP would constitute true platforms to transport polyphenols, or a combination of them, to be used for the designing of a new generation of drugs or nutraceuticals.

pH and ROS sequentially responsive podophyllotoxin prodrug micelles with surface charge-switchable and self-amplification drug release for combating multidrug resistance cancer

Multidrug resistance (MDR) is one of the main reasons for tumor chemotherapy failure. Podophyllotoxin (PPT) has been reported that can suppress MDR cancer cell growth; however, effective delivery of PPT to MDR cancer cells is challenged by cascaded bio-barriers. To effectively deliver PPT to MDR cancer cells, a PPT polymeric prodrug micelle (PCDMA) with the charge-conversion capability and self-acceleration drug release function are fabricated, which is composed of a pH and reactive oxygen species (ROS) sequentially responsive PPT-polymeric prodrug and an ROS generation agent, cucurbitacin B (CuB). After reach to tumor tissue, the surface charge of PCDMA could rapidly reverse to positive in the tumor extracellular environment to promote cellular uptake. Subsequently, the PCDMA could be degraded to release PPT and CuB in response to an intracellular high ROS condition. The released CuB is competent for generating ROS, which in turn accelerates the release of PPT and CuB. Eventually, the released PPT could kill MDR cancer cells. The in vitro and in vivo studies demonstrated that PCDMA was effectively internalized by cancer cells and produces massive ROS intracellular, rapid release drug, and effectively overcame MDR compared with the control cells, due to the tumor-specific weakly acidic and ROS-rich environment. Our results suggest that the pH/ROS dual-responsive PCDMA micelles with surface charge-reversal and self-amplifying ROS-response drug release provide an excellent platform for potential MDR cancer treatment.

Kidney-accumulating olmesartan-loaded nanomicelles ameliorate the organ damage in a murine model of Alport syndrome

ACE inhibitors or angiotensin II receptor blockers (ACEi/ARBs) have been a cornerstone of the management in kidney disease, but their use is often limited by undesired systemic effects, such as symptomatic hypotension. To minimize the extra-renal effects of ACEi/ARBs, we formulated hydrophobically modified glycol chitosan (HGC) nanomicelles releasing olmesartan (HGC-Olm) that specifically accumulated in the kidney, and investigated whether kidney-specific delivery of olmesartan by HGC nanomicelles could ameliorate organ damage in Col4a3^-/- mouse, a murine model of progressive chronic kidney disease mimicking human Alport syndrome. Ex vivo tracing demonstrated that intravenously injected HGC-Olm nanomicelles were specifically delivered to the kidney, with sustained release of olmesartan for more than 48 h. Contrary to the conventional delivery of olmesartan via oral route, injection of HGC-Olm nanomicelles did not alter blood pressure in Col4a3^-/- mice. Immunohistochemistry revealed that HGC nanomicelles were diffusely distributed from the cortex and glomeruli to the outer medulla, sparing the inner medulla. Phenotypic analysis showed that the attenuation of kidney fibrosis in the kidney of Col4a3^-/- mice by HGC-Olm nanomicelles was comparable to that noted with conventionally delivered olmesartan. Therefore, our results suggest that HGC-Olm nanomicelles could be a safe and effective alternative drug delivery system for kidney diseases.

Dual-Targeting Glycol Chitosan/Heparin-Decorated Polypyrrole Nanoparticle for Augmented Photothermal Thrombolytic Therapy

Near-infrared (NIR)-light-modulated photothermal thrombolysis has been investigated to overcome the hemorrhage danger posed by clinical clot-busting substances. A long-standing issue in thrombosis fibrinolytics is the lack of lesion-specific therapy, which should not be ignored. Herein, a novel thrombolysis therapy using photothermal disintegration of a fibrin clot was explored through dual-targeting glycol chitosan/heparin-decorated polypyrrole nanoparticles (GCS-PPY-H NPs) to enhance thrombus delivery and thrombolytic therapeutic efficacy. GCS-PPY-H NPs can target acidic/P-selectin high-expression inflammatory endothelial cells/thrombus sites for initiating lesion-site-specific thrombolysis by hyperthermia using NIR irradiation. A significant fibrin clot-clearance rate was achieved with thrombolysis using dual-targeting/modality photothermal clot disintegration in vivo. The molecular level mechanisms of the developed nanoformulations and interface properties were determined using multiple surface specific analytical techniques, such as particle size distribution, zeta potential, electron microscopy, Fourier-transform infrared spectroscopy (FTIR), wavelength absorbance, photothermal, immunofluorescence, and histology. Owing to the augmented thrombus delivery of GCS-PPY-H NPs and swift treatment time, dual-targeting photothermal clot disintegration as a systematic treatment using GCS-PPY-H NPs can be effectively applied in thrombolysis. This novel approach possesses a promising future for thrombolytic treatment.

PLGA/PCADK composite microspheres containing hyaluronic acid-chitosan siRNA nanoparticles: A rational design for rheumatoid arthritis therapy

Myeloid cell leukemia-1 (Mcl-1), a member of the Bcl-2 anti-apoptotic family, is overexpressed in the synovial macrophages of patients with rheumatoid arthritis (RA). Small interfering RNA (siRNA) Mcl-1 can induce macrophage apoptosis in the joints and is a potential therapeutic target of RA. Nevertheless, the application of siRNA is limited owing to its instability and susceptibility to degradation in vivo. To address these shortcomings, we developed composite microspheres (MPs) loaded with hyaluronic acid (HA)-chitosan (CS) nanoparticles (NPs). First, we synthesized HA-CS/siRNA NPs (HCNPs) using ionotropic gelation process. Then, HCNPs, as an internal aqueous phase, were loaded into poly (D, L-lactide-co-glycolide) (PLGA) and poly (cyclohexane-1,4-diyl acetone dimethylene ketal) (PCADK) MPs using the double emulsion method. The NPs-in-MPs (NiMPs) composite system provided sustained release of NPs, protected siRNA against nuclease degradation in the serum, and could readily cross the cellular membrane. In addition, we evaluated the advantages of NiMPs in an adjuvant-induced arthritis rat model. Our experimental results demonstrate that NiMPs have greater pharmacodynamic effects than common MPs. Meanwhile, compared with HCNPs, NiMPs reduced the frequency of drug administration. Therefore, NiMPs are a promising and novel siRNA delivery vehicle for RA therapy.

Podophyllotoxin-polyacrylic acid conjugate micelles: improved anticancer efficacy against multidrug-resistant breast cancer

BACKGROUND

Podophyllotoxin (PPT) is a naturally occurring compound obtained from the roots of Podophyllum species, indicated for a variety of malignant tumors such as breast, lung, and liver tumors. This toxic polyphenol (PPT) exhibited significant activity against P-glycoprotein (P-gp) mediated multidrug-resistant (MDR) cancer cells. However, extremely poor water solubility, a narrow therapeutic window, and high toxicity have greatly restricted the clinical uses of PPT. Therefore, the present research was aimed to synthesize the water-soluble ester prodrug of PPT with polyacrylic acid (PAA), a water-soluble polymer by Steglich esterification reaction, and to screen it for assay, solubility, in vitro hemolysis, in vitro release, and in vitro anticancer activity.

RESULTS

The Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy results revealed the successful synthesis of podophyllotoxin-polyacrylic acid conjugate (PPC). The assay and saturation solubility of the prodrug is found to be 64.01 ± 4.5% and 1.39 ± 0.05 mg/mL (PPT equivalent) respectively. The PPC showed CMC (critical micelle concentration) of 0.430 mg/mL in distilled water at room temperature. The PPC micelles showed a mean particle size of 215 ± 11 nm with polydispersity index (PDI) of 0.193 ± 0.006. Further, the transmission electron microscope (TEM) results confirmed the self-assembling character of PPC into micelles. The PPC caused significantly less hemolysis (18.6 ± 2.9%) than plain PPT solution. Also, it demonstrated significantly (p < 0.01) higher in vitro cytotoxicity against both sensitive as well as resistance human breast cancer cells (MCF-7 and MDA MB-231) after 48 h of treatment.

CONCLUSION

The obtained study results clearly revealed the notable in vitro anticancer activity of PPT following its esterification with PAA. However, further in vivo studies are needed to ascertain its efficacy against a variety of cancers.

Challenges and potential for improving the druggability of podophyllotoxin-derived drugs in cancer chemotherapy

Covering: up to 2020As a main bioactive component of the Chinese, Indian, and American Podophyllum species, the herbal medicine, podophyllotoxin (PTOX) exhibits broad spectrum pharmacological activity, such as superior antitumor activity and against multiple viruses. PTOX derivatives (PTOXs) could arrest the cell cycle, block the transitorily generated DNA/RNA breaks, and blunt the growth-stimulation by targeting topoisomerase II, tubulin, or insulin-like growth factor 1 receptor. Since 1983, etoposide (VP-16) is being used in frontline cancer therapy against various cancer types, such as small cell lung cancer and testicular cancer. Surprisingly, VP-16 (ClinicalTrials NTC04356690) was also redeveloped to treat the cytokine storm in coronavirus disease 2019 (COVID-19) in phase II in April 2020. The treatment aims at dampening the cytokine storm and is based on etoposide in the case of central nervous system. However, the initial version of PTOX was far from perfect. Almost all podophyllotoxin derivatives, including the FDA-approved drugs VP-16 and teniposide, were seriously limited in clinical therapy due to systemic toxicity, drug resistance, and low bioavailability. To meet this challenge, scientists have devoted continuous efforts to discover new candidate drugs and have developed drug strategies. This review focuses on the current clinical treatment of PTOXs and the prospective analysis for improving druggability in the rational design of new generation PTOX-derived drugs.

pH/redox sequentially responsive nanoparticles with size shrinkage properties achieve deep tumor penetration and reversal of multidrug resistance

pH/redox sequentially responsive nanoparticles with size shrinkage properties achieve deep tumor penetration and reversal of multidrug resistance.

Transferrin receptor-targeted redox/pH-sensitive podophyllotoxin prodrug micelles for multidrug-resistant breast cancer therapy

Podophyllotoxin (PPT), a toxic polyphenol extracted from the roots of Podophyllum species, showed remarkable activity against P-glycoprotein (P-gp) mediated multidrug resistant (MDR) cancer cells. Many PPT-prodrugs based on nano-technology have been developed for increasing aqueous solubility and reducing the side effects of PPT; however, the sensitive linkers in almost all PPT-prodrugs were ester bonds, resulting in slow and incomplete drug release. We developed a redox/pH double-sensitive and tumor active targeted drug delivery system for PPT delivery, in which PPT was covalently coupled to T7-peptide (Pep) modified polyethylene glycol (PEG) or methoxy-polyethylene glycol (mPEG) through a disulfide bond to obtain the final polymer (Pep-PEG-SS-PPT or PEG-SS-PPT). The mixed micelles (Pep-SS-NPs) were made by mixing Pep-PEG-SS-PPT with PEG-SS-PPT, and the mixed micelles showed good size uniformity and high stability in serum solution. The in vitro release experiment showed that about (81.7 ± 2.8)% PPT was released from Pep-SS-NPs in 10 mM glutathione (GSH) at pH 7.4, and also about (64.6 ± 1.7)% PPT was released from Pep-SS-NPs at pH 5.0. In vitro cytotoxicity analysis suggested that Pep-SS-NPs exhibited 57- to 270-fold lower resistance index (RI) values for different drug-resistant cancer cell lines than paclitaxel (PTX) or docetaxel (DTX). The cell uptake assay indicated that the Pep-SS-NPs could significantly enhance the intracellular level of coumarin-6 compared to that of the control group. The maximum tolerated dose (MTD) of Pep-SS-NPs was increased greatly compared to that of free PPT (5.3-fold). In vivo research showed that Pep-SS-NPs significantly enhanced antitumor efficacy against MCF-7/ADR xenograft tumors compared to the control groups. These findings suggest that mixed micelles could be a potentially successful nanomedicine for MDR breast cancer therapy.

Magnetic bio-metal-organic framework nanocomposites decorated with folic acid conjugated chitosan as a promising biocompatible targeted theranostic system for cancer treatment

In this work, a multifunctional magnetic Bio-Metal-Organic Framework (Fe₃O₄@Bio-MOF) coated with folic acid-chitosan conjugate (FC) was successfully prepared for tumor-targeted delivery of curcumin (CUR) and 5-fluorouracil (5-FU) simultaneously. Bio-MOF nanocomposite based on CUR as organic linker and zinc as metal ion was prepared by hydrothermal method in the presence of amine-functionalized Fe₃O₄ magnetic nanoparticles (Fe₃O₄@NH₂ MNPs). 5-FU was loaded in the magnetic Bio-MOF and the obtained nanocarrier was then coated with FC network. The prepared nanocomposite (NC) was fully characterized by high resolution-transmission electron microscope (HR-TEM), field emission scanning electron microscopy (FE-SEM), Dynamic light scattering (DLS), X-ray diffraction analysis (XRD), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), nuclear magnetic resonance (NMR), and UV-vis analyses. In vitro release study showed controlled release of CUR and 5-FU in acidic pH confirming high selectivity and performance of the carrier in cancerous microenvironments. The selective uptake of 5-FU-loaded Fe₃O₄@Bio-MOF-FC by folate receptor-positive MDA-MB-231 cells was investigated and verified. The ultimate nanocarrier exhibited no significant toxicity, while drug loaded nanocarrier showed selective and higher toxicity against the cancerous cells than normal cells. SDS PAGE was also utilized to determine the protein pattern attached on the surface of the nanocarriers. In vitro and in vivo MRI studies showed negative signal enhancement in tumor confirming the ability of the nanocarrier to be applied as diagnostic agent. Owing to the selective anticancer release and cellular uptake, acceptable blood compatibility as well as suitable T₂ MRI contrast performance, the target nanocarrier could be considered as favorable theranostic in breast cancer.

Rational design of curcumin loaded multifunctional mesoporous silica nanoparticles to enhance the cytotoxicity for targeted and controlled drug release

Curcumin has attracted increasing attentions in recent years due to its promising anticancer activities. However, the hydrophobicity of curcumin has limited greatly its efficacy in clinical trials. In this study, folate (FA)-receptor targeting mesoporous silica nanoparticles that promise high loadings of curcumin via pH-sensitive Schiff base reactions were constructed and examined for targeted delivery of curcumin. Such nano-delivery system showed significantly improved stability and biocompatibility of curcumin under physiological conditions. Further investigations demonstrated that this nanocarrier had high values of drug loading efficiency (9.5%) and pH-responsive drug release property. Moreover, the particles could be efficiently internalized by FA-receptor-rich MCF-7 cells through the receptor-mediated endocytosis, whereas FA-receptor-poor HEK-293T normal cells showed much lower endocytosis of the nanoparticles under the same conditions. The in vitro cytotoxicity assay indicated that the curcumin-loaded nanoparticles exhibited significantly enhanced cytotoxicity against MCF-7 cell than HEK-293T cells because of the higher cellular uptake efficiency of nanocarriers. More broadly, this work demonstrates a new type of mesoporous silica nanocarrier particularly useful for targeted and controlled drug release applications.