Synthesis of folic acid-conjugated glycodendrimer with magnetic β-cyclodextrin core as a pH-responsive system for tumor-targeted co-delivery of doxorubicin and curcumin

Cyclodextrins and their potential applications for delivering vitamins, iron, and iodine for improving micronutrient status

Cyclodextrins (CDs) have been investigated as potential biopolymeric carriers that can form inclusion complexes with numerous bioactive ingredients. The inclusion of micronutrients (e.g. vitamins or minerals) into cyclodextrins can enhance their solubility and provide oxidative or thermal stability. It also enables the formulation of products with extended shelf-life. The designed delivery systems with CDs and their inclusion complexes including electrospun nanofibers, emulsions, liposomes, and hydrogels, show potential in enhancing the solubility and oxidative stability of micronutrients while enabling their controlled and sustained release in applications including food packaging, fortified foods and dietary supplements. Nano or micrometer-sized delivery systems capable of controlling burst release and permeation, or moderating skin hydration have been reported, which can facilitate the formulation of several personal and skin care products for topical or transdermal delivery of micronutrients. This review highlights recent developments in the application of CDs for the delivery of micronutrients, i.e. vitamins, iron, and iodine, which play key roles in the human body, emphasizing their existing and potential applications in the food, pharmaceuticals, and cosmeceuticals industries.

Targeted cancer treatment using folate-conjugated sponge-like ZIF-8 nanoparticles: a review

ZIF-8 (zeolitic imidazolate framework-8) is a potential drug delivery system because of its unique properties, which include a large surface area, a large pore capacity, a large loading capacity, and outstanding stability under physiological conditions. ZIF-8 nanoparticles may be readily functionalized with targeting ligands for the identification and absorption of particular cancer cells, enhancing the efficacy of chemotherapeutic medicines and reducing adverse effects. ZIF-8 is also pH-responsive, allowing medication release in the acidic milieu of cancer cells. Because of its tunable structure, it can be easily functionalized to design cancer-specific targeted medicines. The delivery of ZIF-8 to cancer cells can be facilitated by folic acid-conjugation. Hence, it can bind to overexpressed folate receptors on the surface of cancer cells, which holds the promise of reducing unwanted deliveries. As a result of its importance in cancer treatment, the folate-conjugated ZIF-8 was the major focus of this review.

Efficient adsorptive removal of used drugs during the COVID-19 pandemic from contaminated water by magnetic graphene oxide/MIL-88 metal-organic framework/alginate hydrogel beads

Currently, the presence of drugs used in the COVID-19 pandemic in water bodies is worrisome due to their high toxicity, which necessitates their critical removal by developing highly efficient adsorbents. Hence, in this study, alginate hydrogel beads of magnetic graphene oxide@MIL-88 metal-organic framework (GO@Fe3O4@MIL-88@Alg) were prepared for the first time and then utilized as a new absorption system for the removal of COVID-19 drugs such as doxycycline (DOX), hydroxychloroquine (HCQ), naproxen (NAP), and dipyrone (DIP) from aqueous solutions by batch adsorption manner. The effects of different experimental factors, such as adsorbent dosage, contact time, pH, drug concentration, temperature, ionic strength, presence of an external magnetic field (EMF), and magnet distance from the adsorption flask were optimized for the removal of COVID-19 drugs. The adsorption equilibrium isotherm proved that the adsorption process of DOX, HCQ, NAP, and DIP drugs on GO@Fe3O4@MIL-88@Alg hydrogel beads conformed to the Langmuir model and followed the pseudo-second-order adsorption kinetics. The maximum adsorption capacities of DOX, HCQ, NAP, and DIP drugs obtained for GO@Fe3O4@MIL-88@Alg hydrogel beads with the Langmuir model were 131.57, 79.92, 55.55, and 49.26 mg/g at 298 K, respectively. The thermodynamic study suggested a spontaneous endothermic adsorption process. Also, the conclusion from this study confirmed the validity of GO@Fe3O4@MIL-88@Alg hydrogel beads for excellent removal of COVID-19 drugs from water samples. It was also found that the GO@Fe3O4@MIL-88@Alg hydrogel beads could be reused with satisfactory removal efficiency in six cycles. Based on the study, the GO@Fe3O4@MIL-88@Alg hydrogel beads could be considered a sustainable, simple, economical, environmentally friendly absorption system for the removal of pharmaceutical contaminants from water.

Folic acid conjugated poly (Amidoamine) dendrimer grafted magnetic chitosan as a smart drug delivery platform for doxorubicin: In-vitro drug release and cytotoxicity studies

This study reports the development of a magnetic and pH-responsive nanocarrier for targeted delivery and controlled release of doxorubicin (DOX). A multifunctional magnetic chitosan nanocomposite (FA-PAMAMG2-MCS) was fabricated by grafting poly(amidoamine) dendrimer and folic acid onto the MCS surface for active targeting. DOX was loaded into this core-shell bio-nanocomposite via adsorption. Structural and morphological characterization of the prepared nanomaterials was performed using XRD, FT-IR, VSM, TGA, BET, FE-SEM/EDX, and TEM techniques. Adsorption capacity of the FA-PAMAMG2-MCS was optimized by changing diverse parameters, such as pH, initial drug concentration, temperature, contact time, and adsorbent dosage. The maximum adsorption capacity for DOX was 102.85 mg g-1 at 298 K. The in-vitro drug release curve at pHs 5.6 and 7.4 manifested a faster drug release from the prepared nanocarrier in acidic environments and, conversely, a slower release in neutral environments over 48 h. The release kinetics followed Peppas-Sahlin models, showing non-Fickian behavior. Moreover, the in-vitro cytotoxicity studies against the human breast cancer (MDA-MB 231) cell line demonstrated the remarkable anticancer activity of the DOX@FA-PAMAMG2-MCS and declared its potency for nanomedicine applications. This multifunctional system could overcome limitations of conventional chemotherapeutic agents through pH-triggered drug release, enabling targeted cytotoxicity against cancer cells.

pH-sensitive biosystem based on laponite RD/chitosan/polyvinyl alcohol hydrogels for controlled delivery of curcumin to breast cancer cells

In this study, a pH-responsive hydrogels based on laponite rapid dispersion (Lap®)/chitosan (CS)/polyvinyl alcohol (PVA) designed and was used for controlled delivery of the anticancer drug curcumin (CUR). First, it was accomplished by dissolving CUR in Lap® dispersion under the influence of the pH of the environment. Then, in the presence of Lap®CUR cross-linking was incorporated between CS and PVA polymers. The structural features of Lap®CUR/CS@PVA hydrogels are characterized using FT-IR, XRD, SEM/EDS, TEM, TGA, Zeta potential, and XPS. The in vitro drug release profiles confirmed a pH-responsive controlled release of CUR in acidic pH for all hydrogels. During 12 h, the cumulative release of CUR from Lap®CUR/0.1CS@PVA hydrogel was 27.9% and 12.3%, at pH 5.5 and 7.4, respectively. While during three days the release rate reached 48.5% and 18.5%. The CUR release kinetic from hydrogels also suggests that the kinetic data well fitted to the Korsmeyer-Peppas, diffusion-controlled and Fickian diffusion. Furthermore, in vitro cytotoxicity and DAPI staining study clearly illustrated that Lap®CUR/0.1CS@PVA hydrogel had lower cytotoxicity than CUR against MDA-MB 231 cancer cells, which confirmed the controlled release of drug through hydrogels. Meanwhile, in vitro hemolysis, antioxidant and antibacterial tests revealed that the prepared hydrogels have good blood compatibility, excellent antioxidant properties, and antibacterial activity. Based on the obtained results, the designed hydrogels could be potentially applied as pH-controlled drug delivery systems for cancer therapy.

pH-sensitive biocompatible chitosan/sepiolite-based cross-linked citric acid magnetic nanocarrier for efficient sunitinib release

In this study, the magnetite nanoparticles were immobilized on the sepiolite needles via co-precipitation of iron ions. Then, the resulted magnetic sepiolite (mSep) nanoparticles were coated with chitosan biopolymer (Chito) in the presence of citric acid (CA) to prepare mSep@Chito core-shell drug nanocarriers (NCs). TEM images showed magnetic Fe₃O₄ nanoparticles with small sizes (less than 25 nm) on the sepiolite needles. Sunitinib anticancer drug loading efficiencies were ⁓45 and 83.7 % for the NCs with low and high content of Chito, respectively. The in-vitro drug release results exhibited that the mSep@Chito NCs have a sustained release behavior with high pH-dependent properties. Cytotoxic results (MTT assay) showed that the sunitinib-loaded mSep@Chito2 NC had a significant cytotoxic effect on the MCF-7 cell lines. Also, the in-vitro compatibility of erythrocytes, physiological stability, biodegradability, and antibacterial and antioxidant activities of NCs was evaluated. The results showed that the synthesized NCs had excellent hemocompatibility, good antioxidant properties, and were sufficiently stable and biocompatible. Based on the antibacterial data, the minimal inhibitory concentration (MIC) values for mSep@Chito1, mSep@Chito2, and mSep@Chito3 were obtained as 125, 62.5, and 31.2 μg/mL towards S. aureus, respectively. All in all, the prepared NCs could be potentially used as a pH-triggered system for biomedical applications.

Facile preparation of pH-sensitive biocompatible alginate beads havening layered double hydroxide supported metal-organic framework for controlled release from doxorubicin to breast cancer cells

In the present study, a pH-sensitive controlled drug delivery system was prepared from alginate beads impregnated with AlCu layered double hydroxides (LDH) supported copper metal-organic framework (Alg-DOX-Cu MOF-LDH beads) for controlled release from doxorubicin (DOX) to breast cancer cells. The physicochemical properties of Alg-DOX-Cu MOF-LDH beads were determined by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), field emission scanning electron microscopy (FE-SEM), and Zeta potential. The in vitro release studies showed that the Alg-DOX-Cu MOF-LDH beads had more controlled drug release than the DOX-Cu MOF-LDH and in vitro release of DOX from both carriers showed pH-response release behavior. The kinetic adsorption studies also confirmed that the drug release from the DOX-Cu MOF-LDH and Alg-DOX-Cu MOF-LDH beads well obey the Korsmeyer-Peppas model. Meanwhile, in vitro cytotoxicity and DAPI tests on L929 (non-cancerous cells) and MCF-7 (human breast cancer cells) clearly showed that the prepared AlCu LDH and Cu MOF-LDH systems had good biocompatibility. Whereas, Alg-DOX-Cu MOF-LDH beads had higher cytotoxicity effects as a result of the controlled release of DOX to MCF-7 cells. These results suggested that the Alg-DOX-Cu MOF-LDH beads can be used as an excellent drug delivery system for cancer therapy and other biomedical applications.

Fabrication of biocompatible magnetic maltose/MIL-88 metal-organic frameworks decorated with folic acid-chitosan for targeted and pH-responsive controlled release of doxorubicin

Recently, metal-organic frameworks (MOFs) have attracted tremendous attention as promising porous drug delivery systems for cancer treatment. In this work, for the first time, a novel magnetic maltose disaccharide molecule modified with MIL-88 metal-organic framework (Fe₃O₄@C@MIL-88) was prepared, and then this targeted system was used for the delivery of the doxorubicin (DOX) drug. Eventually, Fe₃O₄@C@MIL-88-DOX were successfully decorated with folic acid conjugated chitosan (Fe₃O₄@C@MIL-88-DOX-FC) as a new targeted and controlled release drug system for treatment of MCF-7 breast cancer. The encapsulation efficiency of the DOX in the Fe₃O₄@C@MIL-88 was obtained at ∼83.6%. The in vitro drug release profiles showed a pH-responsive controlled release of DOX in acidic pH confirming the performance of the systems in the cancerous environment. The DOX release mechanism from systems at pH 5 also showed that the kinetic data well fitted to the Korsmeyer-Peppas and Fickian diffusion. Furthermore, in vitro cytotoxicity and DAPI staining study clearly illustrated that the synthesized Fe₃O₄@C@MIL-88 system had low cytotoxicity and good biocompatibility against MCF-7 cancer cells and MCF-10A normal cells. Whereas, Fe₃O₄@C@MIL-88-DOX and Fe₃O₄@C@MIL-88-DOX-FC exhibited good antitumor activity as a result of targeted delivery of DOX, which indicated the MCF-7 cell death with apoptotic effects. Based on these findings, the resulting carriers could be used as promising targeted drug delivery systems for cancer therapy.

Magnetic alginate/glycodendrimer beads for efficient removal of tetracycline and amoxicillin from aqueous solutions

The release of antibiotic drugs into aquatic environments is a serious environmental and health problem in recent years. Therefore, the development of potential adsorbents for the effective removal of tetracycline (TC) and amoxicillin (AMX) of aqueous media is of great importance. In this study, new alginate beads were successfully prepared by encapsulation of Fe₃O₄@maltose-functionalized triazine dendrimer in alginate (Alg/Fe₃O₄@C@TD) for the first time. The obtained beads were utilized as a well adsorbent for the removal of TC and AMX antibiotics from aqueous solutions by batch adsorption procedure. The characteristics of the synthesized beads were investigated using FT-IR, Zeta potential, SEM, XRD, EDX, VSM, and BET. The effects of various operation factors such as adsorbent dose, pH of the solution, contact time, antibiotic initial concentration, temperature, and ionic strength on the removal of antibiotics were studied. Moreover, Langmuir and Freundlich adsorption isotherm results showed that the Langmuir model fitted well for the adsorption of both antibiotics onto Alg/Fe₃O₄@C@TD beads. Based on the Langmuir model, the maximum adsorption capacity of TC and AMX onto Alg/Fe₃O₄@C@TD beads at 25 °C was 454.54 and 400 mg/g, respectively. Kinetic and thermodynamic studies also indicated that the TC and AMX adsorption were found to be well fitted with a pseudo-second-order kinetic model, feasible, endothermic, and spontaneous in nature. In addition, the Alg/Fe₃O₄@C@TD beads showed excellent reusability for removal from both antibiotics after six adsorption cycles. Overall, the obtained results suggest that Alg/Fe₃O₄@C@TD beads could be considered as a low-cost and eco-friendly adsorbent for antibiotic contaminants removal from aquatic media.

Targeted delivery of capecitabine to colon cancer cells using nano polymeric micelles based on beta cyclodextrin

Nano polymeric micelles (nano PMs) help to increase accessibility to tumor sites, decrease side effects and allow controlled drug dissemination over a long period of time. The aim of this study was to optimize the delivery of the anticancer drug capecitabine (CAP) using nano PMs and cyclodextrin (CD) to allow the treatment of colon cancer. A pH-responsive copolymer was prepared and the variables of loading time, loading temperature, the amount of copolymer and also the ratio of acrylic/maleic copolymer to beta CD and the effect that these variables have on drug loading were investigated, with variable optimization studies carried out following a definitive screening design (DSD). The morphology and structure of the particles were determined by scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) spectroscopy. In vitro drug release exemplified that the micelles were pH-sensitive, this action was shown that firstly the drug release was done perfectly targeted and under control and secondly the drug has been released above 80% inside the colon.

Nano polymeric micelles (nano PMs) help to increase accessibility to tumor sites, decrease side effects and allow controlled drug dissemination over a long period of time.