Mesoporous silica nanoparticles functionalized with folic acid/methionine for active targeted delivery of docetaxel

Boosting antitumor efficacy using docetaxel-loaded nanoplatforms: from cancer therapy to regenerative medicine approaches

The intersection of nanotechnology and pharmacology has revolutionized the delivery and efficacy of chemotherapeutic agents, notably docetaxel, a key drug in cancer treatment. Traditionally limited by poor solubility and significant side effects, docetaxel's therapeutic potential has been significantly enhanced through its incorporation into nanoplatforms, such as nanofibers and nanoparticles. This advancement offers targeted delivery, controlled release, and improved bioavailability, dramatically reducing systemic toxicity and enhancing patient outcomes. Nanofibers provide a versatile scaffold for the controlled release of docetaxel, utilizing techniques like electrospinning to tailor drug release profiles. Nanoparticles, on the other hand, enable precise drug delivery to tumor cells, minimizing damage to healthy tissues through sophisticated encapsulation methods such as nanoprecipitation and emulsion. These nanotechnologies not only improve the pharmacokinetic properties of docetaxel but also open new avenues in regenerative medicine by facilitating targeted therapy and cellular regeneration. This narrative review highlights the transformative impact of docetaxel-loaded nanoplatforms in oncology and beyond, showcasing the potential of nanotechnology to overcome the limitations of traditional chemotherapy and pave the way for future innovations in drug delivery and regenerative therapies. Through these advancements, nanotechnology promises a new era of precision medicine, enhancing the efficacy of cancer treatments while minimizing adverse effects.

Engineered mesoporous silica nanoparticles, new insight nanoplatforms into effective cancer gene therapy

The use of nucleic acid to control the expression of genes relevant to tumor progression is a key therapeutic approach in cancer research. Therapeutics based on nucleic acid provide novel concepts for untreatable targets. Nucleic acids as molecular medications must enter the target cell to be effective and obstacles in the systemic delivery of DNA or RNA limit their use in a clinical setting. The creation of nucleic acid delivery systems based on nanoparticles in order to circumvent biological constraints is advancing quickly. The ease of synthesis and surface modification, biocompatibility, biodegradability, cost-effectiveness and high loading capability of nucleic acids have prompted the use of mesoporous silica nanoparticles (MSNs) in gene therapy. The unique surface features of MSNs facilitate their design and decoration for high loading of nucleic acids, immune system evasion, cancer cell targeting, controlled cargo release, and endosomal escape. Reports have demonstrated successful therapeutic outcomes with the administration of a variety of engineered MSNs capable of delivering genes to tumor sites in laboratory animals. This comprehensive review of studies about siRNA, miRNA, shRNA, lncRNA and CRISPR/Cas9 delivery by MSNs reveals engineered MSNs as a safe and efficient system for gene transfer to cancer cells and cancer mouse models.

Peptide-Hydrogel Nanocomposites for Anti-Cancer Drug Delivery

Cancer is the second leading cause of death globally, but conventional anticancer drugs have side effects, mainly due to their non-specific distribution in the body in both cancerous and healthy cells. To address this relevant issue and improve the efficiency of anticancer drugs, increasing attention is being devoted to hydrogel drug-delivery systems for different kinds of cancer treatment due to their high biocompatibility and stability, low side effects, and ease of modifications. To improve the therapeutic efficiency and provide multi-functionality, different types of nanoparticles (NPs) can be incorporated within the hydrogels to form smart hydrogel nanocomposites, benefiting the advantages of both counterparts and suitable for advanced anticancer applications. Despite many papers on non-peptide hydrogel nanocomposites, there is limited knowledge about peptide-based nanocomposites, specifically in anti-cancer drug delivery. The aim of this short but comprehensive review is, therefore, to focus attention on the synergies resulting from the combination of NPs with peptide-based hydrogels. This review, which includes a survey of recent advances in this kind of material, does not aim to be an exhaustive review of hydrogel technology, but it instead highlights recent noteworthy publications and discusses novel perspectives to provide valuable insights into the promising synergic combination of peptide hydrogels and NPs for the design of novel anticancer drug delivery systems.

Nanocore-Shell Bone Filler Contained Mesoporous Silica Modified with Hydroxyapatite Precursors; Wrapped in a Natural Metal-Phenolic Network

Various therapeutic strategies have been developed to address bone diseases caused by aging society and skeletal defects caused by trauma or accidental events. One such approach is using bone fillers, such as hydroxyapatite (HA) and bioactive glasses. Although they have provided effective osteogenesis, infection and inflammation due to the surgical procedure and uncontrolled ion release can hinder the efficiency of bone regeneration. In response to these challenges, immobilizing a neutral metal-phenolic network on the surface of osteoconductive nanoparticles would be the master key to achieving a gradual, controlled release during the mineralization period and reducing infection and inflammation through biological pathways. In this regard, a mesoporous silica nanocomposite modified by an HA precursor was synthesized to enhance bone regeneration. In addition, to improve the therapeutic effects, its surface was wrapped with a magnesium-phenolic network made from pomegranate extract, which can simultaneously produce anti-inflammatory and antibacterial effects. The obtained core-shell nanocomposite was characterized by its physicochemical properties, biocompatibility, and bioactivity. The in vitro studies revealed that the synthesized nanocomposite exhibits higher osteogenic activity than the control groups, as confirmed by alizarin red staining. Moreover, the nanocomposite maintained low toxicity as measured by the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay and increased antibacterial activity against Staphylococcus aureus and Escherichia coli compared with the control groups. Therefore, this research presents a promising strategy for bone regeneration, combining the advantages of mesoporous silica nanocomposite modified by an HA precursor with the beneficial effects of a magnesium-phenolic network.

Validation of Dual-Action Chemo-Radio-Labeled Nanocarriers with High Efficacy against Triple-Negative Breast Cancer

Identification and selectivity of molecular targets with prolonged action for difficult-to-target cancer such as triple-negative breast cancer (TNBC) represent a persisting challenge in the precision delivery of therapeutics. In the quest to target undruggable sites, this study validates the bioavailability of polydopamine-sealed mesoporous silica nanocarriers (PDA-mSiO2) for in vivo drug delivery to TNBC. For controlled transport and release, the chemotherapeutic drug doxorubicin was encapsulated in mSiO2 nanocarriers coated with a PDA layer serving as a stimuli-responsive gatekeeper or seal. For unifying targeting and treatment modalities, these nanocarriers were covalently conjugated to a macrocyclic chelator (DOTA) and folate (FA-mSiO2.) that enabled incorporation of radionuclides and identification of FR Alpha (FolRα) receptors present on TNBC cells. The robust chemical design of FA- and DOTA-functionalized PDA-coated mSiO2 nanocarriers constitutes mild reaction conditions to avoid the loss of surface-bound molecules. The radiolabeling studies with the theranostic pair 68Ga and 177Lu showed quantitative trends for radiochemical efficacy and purity. Nanocarriers equipped with both radiolabels and affinity ligands were optimally stable when incubated with human serum for up to 120 h (177Lu), demonstrating hydrophilicity with a partition coefficient (log P) of -3.29 ± 0.08. Specifically, when incubated with TNBC cells, the cells received significant FA-mSiO2 carriers, demonstrating efficient carrier internalization and time-dependent uptake. Moreover, in vivo results visualize the retention of drug-filled carriers at the tumor sites for a long time, which holds promise for therapeutic studies. This research work demonstrates for the first time the successful dual conjugation of nanocarriers through the colocation of radionuclides and anticancer drugs that is promising for both live molecular imaging and enhanced therapeutic effect for TNBC.

Mesoporous Silica Nanoparticles Coated with Carboxymethyl Chitosan for 5-Fluorouracil Ocular Delivery: Characterization, In Vitro and In Vivo Studies

This study investigates the development of topically applied non-invasive amino-functionalized silica nanoparticles (AMSN) and O-Carboxymethyl chitosan-coated AMSN (AMSN-CMC) for ocular delivery of 5-Fluorouracil (5-FU). Particle characterization was performed by the DLS technique (Zeta-Sizer), and structural morphology was examined by SEM and TEM. The drug encapsulation and loading were determined by the indirect method using HPLC. Physicochemical characterizations were performed by NMR, TGA, FTIR, and PXRD. In vitro release was conducted through a dialysis membrane in PBS (pH 7.4) using modified Vertical Franz diffusion cells. The mucoadhesion ability of the prepared nanoparticles was tested using the particle method by evaluating the change in zeta potential. The transcorneal permeabilities of 5-FU from AMNS-FU and AMSN-CMC-FU gel formulations were estimated through excised goat cornea and compared to that of 5-FU gel formulation. Eye irritation and ocular pharmacokinetic studies from gel formulations were evaluated in rabbit eyes. The optimum formulation of AMSN-CMC-FU was found to be nanoparticles with a particle size of 249.4 nm with a polydispersity of 0.429, encapsulation efficiency of 25.8 ± 5.8%, and drug loading capacity of 5.2 ± 1.2%. NMR spectra confirmed the coating of AMSN with the CMC layer. In addition, TGA, FTIR, and PXRD confirmed the drug loading inside the AMSN-CMC. Release profiles showed 100% of the drug was released from the 5-FU gel within 4 h, while AMSN-FU gel released 20.8% of the drug and AMSN-CMC-FU gel released around 55.6% after 4 h. AMSN-CMC-FU initially exhibited a 2.45-fold increase in transcorneal flux and apparent permeation of 5-FU compared to 5-FU gel, indicating a better corneal permeation. Higher bioavailability of AMSN-FU and AMSN-CMC-FU gel formulations was found compared to 5-FU gel in the ocular pharmacokinetic study with superior pharmacokinetics parameters of AMSN-CMC-FU gel. AMSN-CMC-FU showed 1.52- and 6.14-fold higher AUC0-inf in comparison to AMSN-FU and 5-FU gel, respectively. AMSN-CMC-FU gel and AMSN-FU gel were "minimally irritating" to rabbit eyes but showed minimal eye irritation potency in comparison to the 5 FU gel. Thus, the 5-FU loaded in AMSN-CMC gel could be used as a topical formulation for the treatment of ocular cancer.

pH-responsive and targeted delivery of chrysin via folic acid-functionalized mesoporous silica nanocarrier for breast cancer therapy

Cancer is a disease of global importance. In order to mitigate conventional chemotherapy-related side effects, phytochemicals with inherent anticancer efficacy have been opted. However, the use of nanotechnology is essential to enhance the bioavailability and therapeutic efficacy of these phytochemicals. Herein, we have formulated folic acid conjugated polyacrylic acid capped mesoporous silica nanoparticles (∼47.6 nm in diameter) for pH-dependent targeted delivery of chrysin to breast cancer (MCF-7) cells. Chrysin loaded mesoporous silica nanoparticles (Chr- mSiO2@PAA/FA) have been noted to induce apoptosis in MCF-7 cells through oxidative insult and mitochondrial dysfunction with subsequent G1 arrest. Further, in tumor bearing mice, intravenous incorporation of Chr-mSiO2@PAA/FA has been noticed to enhance the anti-neoplastic effects of chrysin via tumor site-specific accumulation. Enhanced cytotoxicity of chrysin contributed towards in vivo tumor regression, restoration of normalized tissue architecture and maintenance of healthy body weight. Besides, no serious systemic toxicity was manifested in response to Chr-mSiO2@PAA/FA administration in vivo. Thus, the study evokes about the anticancer potentiality of chrysin and its increased therapeutic activity via incorporation into folic acid conjugated mesoporous silica nanoparticles, which may hold greater impact in field of future biomedical research.

Tenofovir-tethered gold nanoparticles as a novel multifunctional long-acting anti-HIV therapy to overcome deficient drug delivery-: an in vivo proof of concept

BACKGROUND

The adoption of Antiretroviral Therapy (ART) substantially extends the life expectancy and quality of HIV-infected patients. Yet, eliminating the latent reservoirs of HIV to achieve a cure remains an unmet need. The advent of nanomedicine has revolutionized the treatment of HIV/AIDS. The present study explores a unique combination of Tenofovir (TNF) with gold nanoparticles (AuNPs) as a potential therapeutic approach to overcome several limitations of the current ART.

RESULTS

TNF-tethered AuNPs were successfully synthesized. Cell viability, genotoxicity, haemolysis, and histopathological studies confirmed the complete safety of the preparation. Most importantly, its anti-HIV1 reverse transcriptase activity was ~ 15 folds higher than the native TNF. In addition, it exhibited potent anti-HIV1 protease activity, a much sought-after target in anti-HIV1 therapeutics. Finally, the in vivo biodistribution studies validated that the AuNPs could reach many tissues/organs, serving as a secure nest for HIV and overcoming the problem of deficient drug delivery to HIV reservoirs.

CONCLUSIONS

We show that the combination of TNF and AuNPs exhibits multifunctional activity, viz. anti-HIV1 and anti-HIV1 protease. These findings are being reported for the first time and highlight the prospects of developing AuNP-TNF as a novel next-generation platform to treat HIV/AIDS.

Preparation and characterization of tamoxifen loaded silica and NH2 functionalized mesoporous silica nanoparticles as delivery systems against MCF-7 breast cancer cells

Objectives

Controlled drug delivery using nanotechnology enhances drug targeting at the site of interest and prevents drug dispersal throughout the body. This study focused on loading a poorly water-soluble drug tamoxifen (TMX) into silica nanoparticles (SNPs) and amine-functionalized mesoporous silica nanoparticles (NH2-SBA-15).

Materials and Methods

SNPs were prepared according to the Stöber method and functionalized with an amine group using 3-aminopropyl triethoxysilane (APTES) through a one-pot synthesis method to produce amine-functionalized mesoporous silica nanoparticles (NH2-SBA-15). Characterization of both nanoparticles was performed using FT-IR, FE-SEM, CHN analysis, porosity tests (BET), and dynamic light scattering (DLS).

Results

The results showed an average particle size of 103.7 nm for SNPs and 225.9 nm for NH2-SBA-15. Based on the BET results, the pore size of NH2-SBA-15 was about 5.4 nm. In both silica nanoparticles, drug release at pH=5.7 was greater than that of pH=7.4. However, Tamoxifen-loaded NH2-SBA-15 (TMX@NH2-SBA-15) indicated the highest drug release in the acidic medium among TMX-loaded SNPs (TMX@SNPs), perhaps due to the high columbic repulsion in the functionalized NH2-SBA-15 nanoparticles. Regarding cytotoxicity results against MCF-7 breast cancer cell lines, both TMX@SNPs and TMX@NH2-SBA-15 nanoparticles exhibited greater cytotoxicity compared to the free TMX as a positive control. Although TMX@SNPs had a small size and high loading capacity, the cytotoxic effects were higher than those of TMX@NH2-SBA-15.

Conclusion

Amine functionalization of SNPs can improve the potential activity of these nanoparticles for target therapy.

Rational Fabrication of Folate-Conjugated Zein/Soy Lecithin/Carboxymethyl Chitosan Core-Shell Nanoparticles for Delivery of Docetaxel

The objective of this work is to design and fabricate a natural zein-based nanocomposite with core-shell structure for the delivery of anticancer drugs. As for the design, folate-conjugated zein (Fa-zein) was synthesized as the inner hydrophobic core; soy lecithin (SL) and carboxymethyl chitosan (CMC) were selected as coating components to form an outer shell. As for fabrication, a novel and appropriate atomizing/antisolvent precipitation process was established. The results indicated that Fa-zein/SL/CMC core-shell nanoparticles (FZLC NPs) were successfully produced at a suitable mass ratio of Fa-zein/SL/CMC (100:30:10) and the freeze-dried FZLC powder showed a perfect redispersibility and stability in water. After that, docetaxel (DTX) as a model drug was encapsulated into FZLC NPs at different mass ratios of DTX to FZLC (MR). When MR = 1:15, DTX/FZLC NPs were obtained with high encapsulation efficiency (79.22 ± 0.37%), small particle size (206.9 ± 48.73 nm), and high zeta potential (-41.8 ± 3.97 mV). DTX was dispersed in the inner core of the FZLC matrix in an amorphous state. The results proved that DTX/FZLC NPs could increase the DTX dissolution, sustain the DTX release, and enhance the DTX cytotoxicity significantly. The present study provides insight into the formation of zein-based complex nanocarriers for the delivery of anticancer drugs.

Enhancement of anti-neoplastic effects of cuminaldehyde against breast cancer via mesoporous silica nanoparticle based targeted drug delivery system

AIMS

Synthesis of novel drug delivery system for targeted delivery of cuminaldehyde to breast cancer cells and the subsequent analyses of anti-neoplastic potential of the drug.

MAIN METHODS

3-carboxy-phenyl boronic acid (PBA) conjugated and polyacrylic acid (PAA) gated mesoporous silica nanoparticles (MSNs) were synthesized for the targeted delivery of cuminaldehyde (CUM) to breast cancer cells. Enhancement of anti-neoplastic effects of cuminaldehyde (4-isopropylbenzaldehyde) by the nanoconjugates was assessed.

KEY FINDINGS

The anti-cancer effects of non-targeted and targeted drug-nanoconjugates were examined in vitro and in vivo. The targeted drug-nanoconjugates caused cell cycle arrest and induced the intrinsic pathway of apoptosis in MCF-7 cells through mitochondrial damage. In vivo intravenous injection of the targeted drug-nanoconjugates led to effective reduction in growth of 4 T1 induced mammary pad tumor in female BALB/c mice via augmented accumulation of cuminaldehyde. The drug-nanoconjugates did not exhibit any systemic toxicity.

SIGNIFICANCE

Therefore, MSN-PBA-CUM-PAA represents a potent therapeutic model for breast cancer treatment.

Nanoarchitectured prototypes of mesoporous silica nanoparticles for innovative biomedical applications

Despite exceptional morphological and physicochemical attributes, mesoporous silica nanoparticles (MSNs) are often employed as carriers or vectors. Moreover, these conventional MSNs often suffer from various limitations in biomedicine, such as reduced drug encapsulation efficacy, deprived compatibility, and poor degradability, resulting in poor therapeutic outcomes. To address these limitations, several modifications have been corroborated to fabricating hierarchically-engineered MSNs in terms of tuning the pore sizes, modifying the surfaces, and engineering of siliceous networks. Interestingly, the further advancements of engineered MSNs lead to the generation of highly complex and nature-mimicking structures, such as Janus-type, multi-podal, and flower-like architectures, as well as streamlined tadpole-like nanomotors. In this review, we present explicit discussions relevant to these advanced hierarchical architectures in different fields of biomedicine, including drug delivery, bioimaging, tissue engineering, and miscellaneous applications, such as photoluminescence, artificial enzymes, peptide enrichment, DNA detection, and biosensing, among others. Initially, we give a brief overview of diverse, innovative stimuli-responsive (pH, light, ultrasound, and thermos)- and targeted drug delivery strategies, along with discussions on recent advancements in cancer immune therapy and applicability of advanced MSNs in other ailments related to cardiac, vascular, and nervous systems, as well as diabetes. Then, we provide initiatives taken so far in clinical translation of various silica-based materials and their scope towards clinical translation. Finally, we summarize the review with interesting perspectives on lessons learned in exploring the biomedical applications of advanced MSNs and further requirements to be explored.

Targeted Delivery Methods for Anticancer Drugs

Simple Summary

The current main technological strategies for the delivery of anticancer drugs are discussed herein. This comprehensive review may help researchers design suitable delivery systems.

Abstract

Several drug-delivery systems have been reported on and often successfully applied in cancer therapy. Cell-targeted delivery can reduce the overall toxicity of cytotoxic drugs and increase their effectiveness and selectivity. Besides traditional liposomal and micellar formulations, various nanocarrier systems have recently become the focus of developmental interest. This review discusses the preparation and targeting techniques as well as the properties of several liposome-, micelle-, solid-lipid nanoparticle-, dendrimer-, gold-, and magnetic-nanoparticle-based delivery systems. Approaches for targeted drug delivery and systems for drug release under a range of stimuli are also discussed.

Curcumin delivery by modified biosourced carbon-based nanoparticles

Aim: To prepare a novel hybrid system for the controlled release and delivery of curcumin (CUR). Methods: A method for the ultrasound-assisted fabrication of protein-modified nanosized graphene oxide-like carbon-based nanoparticles (CBNPs) was developed. After being modified with bovine serum albumin (BSA), CUR was loaded onto the synthesized hybrid (labeled CBNPs@BSA-CUR). The structure and properties of the synthesized nanoparticles were elucidated using transmission electron microscopy (TEM), atomic force microscopy (AFM), ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS) methods. Results: CBNPs@BSA-CUR showed pH sensitivity and were calculated as controlled CUR release behavior. The drug-free system exhibited good biocompatibility and was nontoxic. However, CBNPs@BSA-CUR showed acceptable antiproliferative ability against MCF-7 breast cancer cells. Conclusion: CBNPs@BSA-CUR could be considered a highly promising nontoxic nanocarrier for the delivery of CUR with good biosafety.

Synthesis and characterization of amine-functionalized Fe3O4/Mesoporous Silica Nanoparticles (MSNs) as potential nanocarriers in drug delivery systems

Superparamagnetic Iron Oxide Nanoparticles (SPIONs) have shown great potential for being utilized in Nanocarriers (NCs) applications throughout the Drug Delivery System (DDS). However, there are several obstacles to make a practical magnetic NCs, such as low dispersity and high toxicity in the biological systems, and also low surface area for drug loading. In this work, magnetic NCs have been synthesized through a facile three-step process, first SPIONs were synthesized by the co-precipitation method, then decorated via mesoporous silica and finally the calcinated NCs functionalized with NH2 by a simple process in the ethanol solvent. The structure and morphology of the as-synthesized NCs have been characterized by the usage of different analyzing methods such as XRD, FTIR, TEM, FE-SEM, and TGA. Also, the magnetic properties have been investigated by the means of VSM throughout each step of the procedure. Lastly, we have applied the technique of N₂ adsorption-desorption to observe the surface area, pore size, and volume. Besides optimal magnetization of final nanoparticles (30 emu/gr), the as-synthesized NCs claimed the high surface area and small diameter, at 371 m².g^-1 and 70 nm, respectively. Moreover, the functionalized NCs have demonstrated well dispersity over a day in the PBS solution. As a result, the as-prepared nanocarrier able to overcome drug delivery obstacles and used as a potential nanocarrier owing to its small diameter, high surface area/ pore volume, optimal magnetization, and well dispersity in the biological condition.

Recent Advances in the Local Drug Delivery Systems for Improvement of Anticancer Therapy

The conventional anticancer chemotherapies not only cause serious toxic effects, but also produce resistance in tumor cells exposed to long-term therapy. Usually, the killing of metastasized cancer cells requires long-term therapy with higher drug doses, because the cancer cells develop resistance due to the induction of poly-glycoproteins (P-gps) that act as a transmembrane efflux pump to transport drugs out of the cells. During the last few decades, scientists have been exploring new anticancer drug delivery systems such as microencapsulation, hydrogels, and nanotubes to improve bioavailability, reduce drug-dose requirement, decrease multiple drug resistance, and to save normal cells as non-specific targets. Hopefully, the development of novel drug delivery vehicles (nanotubes, liposomes, supramolecules, hydrogels, and micelles) will assist to deliver drug molecules at the specific target site and reduce the undesirable side effects of anticancer therapies in humans. Nanoparticles and lipid formulations are also designed to deliver small drug payload at the desired tumor cell sites for their anticancer actions. This review will focus on the recent advances in the drug delivery systems, and their application in treating different cancer types in humans.

An updated review of folate-functionalized nanocarriers: A promising ligand in cancer

The uncontrolled release of drugs in conventional drug delivery systems has led to the introduction of new nanotechnology-based drug delivery systems and the use of targeted nanocarriers for cancer treatment. These targeted nanocarriers, which consist of intelligent nanoparticles modified with targeting ligands, can deliver drugs to specified locations at the right time and reduce drug doses to prevent side effects. Folate is a suitable targeting ligand for folate receptors overexpressed on cancer cells and has shown promising results in the diagnosis and treatment of cancer. In this review, we highlight the latest developments on the use of folate-conjugated nanoparticles in cancer diagnosis and treatment. Moreover, the toxicity, biocompatibility and efficacy of these nanocarriers are discussed.

siRNA delivery using intelligent chitosan-capped mesoporous silica nanoparticles for overcoming multidrug resistance in malignant carcinoma cells

Although siRNA is a promising technology for cancer gene therapy, effective cytoplasmic delivery has remained a significant challenge. In this paper, a potent siRNA transfer system with active targeting moieties toward cancer cells and a high loading capacity is introduced to inhibit drug resistance. Mesoporous silica nanoparticles are of great potential for developing targeted gene delivery. Amino-modified MSNs (NH₂-MSNs) were synthesized using a modified sol–gel method and characterized by FTIR, BET, TEM, SEM, X-ray diffraction, DLS, and ¹H-NMR. MDR1-siRNA was loaded within NH₂-MSNs, and the resulting negative surface was capped by functionalized chitosan as a protective layer. Targeting moieties such as TAT and folate were anchored to chitosan via PEG-spacers. The loading capacity of siRNA and the protective effect of chitosan for siRNA were determined by gel retardation assay. MTT assay, flow cytometry, real-time PCR, and western blot were performed to study the cytotoxicity, cellular uptake assay, targeting evaluation, and MDR1 knockdown efficiency. The synthesized NH₂-MSNs had a particle size of ≈ 100 nm and pore size of ≈ 5 nm. siRNA was loaded into NH₂-MSNs with a high loading capacity of 20% w/w. Chitosan coating on the surface of siRNA-NH₂-MSNs significantly improved the siRNA protection against enzyme activity compared to naked siRNA-NH₂-MSNs. MSNs and modified MSNs did not exhibit significant cytotoxicity at therapeutic concentrations in the EPG85.257-RDB and HeLa-RDB lines. The folate-conjugated nanoparticles showed a cellular uptake of around two times higher in folate receptor-rich HeLa-RDB than EPG85.257-RDB cells. The chitosan-coated siRNA-NH2-MSNs produced decreased MDR1 transcript and protein levels in HeLa-RDB by 0.20 and 0.48-fold, respectively. The results demonstrated that functionalized chitosan-coated siRNA-MSNs could be a promising carrier for targeted cancer therapy. Folate-targeted nanoparticles were specifically harvested by folate receptor-rich HeLa-RDB and produced a chemosensitized phenotype of the multidrug-resistant cancer cells.

Recent Technologies for Amorphization of Poorly Water-Soluble Drugs

Amorphization technology has been the subject of continuous attention in the pharmaceutical industry, as a means to enhance the solubility of poorly water-soluble drugs. Being in a high energy state, amorphous formulations generally display significantly increased apparent solubility as compared to their crystalline counterparts, which may allow them to generate a supersaturated state in the gastrointestinal tract and in turn, improve the bioavailability. Conventionally, hydrophilic polymers have been used as carriers, in which the amorphous drugs were dispersed and stabilized to form polymeric amorphous solid dispersions. However, the technique had its limitations, some of which include the need for a large number of carriers, the tendency to recrystallize during storage, and the possibility of thermal decomposition of the drug during preparation. Therefore, emerging amorphization technologies have focused on the investigation of novel amorphous-stabilizing carriers and preparation methods that can improve the drug loading and the degree of amorphization. This review highlights the recent pharmaceutical approaches utilizing drug amorphization, such as co-amorphous systems, mesoporous particle-based techniques, and in situ amorphization. Recent updates on these technologies in the last five years are discussed with a focus on their characteristics and commercial potential.

Fabrication of Bio-Nanocomposite Based on HNT-Methionine for Controlled Release of Phenytoin

In this study, a novel promising approach for the fabrication of Halloysite nanotube (HNT) nanocomposites, based on the amino acid named Methionine (Met), was investigated. For this purpose, Met layered on the outer silane functionalized surface of HNT for controlled release of Phenytoin sodium (PHT). The resulting nanocomposite (MNT-g-Met) was characterized by FTIR, XRD, Zeta potential, TGA, TEM and FE-SEM. The FT-IR results showed APTES and Met peaks, which proved the modification of the HNTs. The zeta-potential results showed the interaction between APTES (+53.30) and Met (+38.80) on the HNTs (-30.92). The FE-SEM micrographs have displayed the grafting of Met on the modified HNTs due to the nanotube conversion to a rough and indistinguishable form. The amount of encapsulation efficiency (EE) and loading efficiency (LE) of MNT-g-Met was 74.48% and 37.24%, while pure HNT was 57.5%, and 28.75%, respectively. In-vitro studies showed that HNT had a burst release (70% in 6 h) in phosphate buffer while MNT-g-Met has more controlled release profile (30.05 in 6 h) and it was found to be fitted with the Korsmeyer-Peppas model. Due to the loading efficiency and controlled release profile, the nanocomposite promote a good potential for drug delivery of PHT.

Advanced mesoporous silica nanocarriers in cancer theranostics and gene editing applications

Targeted nanomaterials for cancer theranostics have been the subject of an expanding volume of research studies in recent years. Mesoporous silica nanoparticles (MSNs) are particularly attractive for such applications due to possibilities to synthesize nanoparticles (NPs) of different morphologies, pore diameters and pore arrangements, large surface areas and various options for surface functionalization. Functionalization of MSNs with different organic and inorganic molecules, polymers, surface-attachment of other NPs, loading and entrapping cargo molecules with on-desire release capabilities, lead to seemingly endless prospects for designing advanced nanoconstructs exerting multiple functions, such as simultaneous cancer-targeting, imaging and therapy. Describing composition and multifunctional capabilities of these advanced nanoassemblies for targeted therapy (passive, ligand-functionalized MSNs, stimuli-responsive therapy), including one or more modalities for imaging of tumors, is the subject of this review article, along with an overview of developments within a novel and attractive research trend, comprising the use of MSNs for CRISPR/Cas9 systems delivery and gene editing in cancer. Such advanced nanconstructs exhibit high potential for applications in image-guided therapies and the development of personalized cancer treatment.

In vivo therapeutic evaluation of a novel bis-lawsone derivative against tumor following delivery using mesoporous silica nanoparticle based redox-responsive drug delivery system

Herein, we have evaluated the in vivo therapeutic efficacy and systemic toxicity profile of a synthetic anticancer compound [3,3'-((4-(trifluoromethyl)phenyl)methylene)bis(2-hydroxynaphthalene-1,4-dione)]. A multifunctional mesoporous silica nanoparticle (MSN) based drug delivery network was also fabricated which specifically showed targeting nature towards the cancer cell. The mesopores of silica nanoparticles were tagged with phenyl boronic acid (PBA) for targeted drug delivery into tumor tissue. 1j was then loaded inside the nanocarriers followed by pore blocking with gold nanoparticles (GN) to attain a redox-responsive controlled drug delivery pattern. The synthesized nanocarriers (1j@-MSN-PBA-GN) having mean diameter of ~86 nm exhibited a moderate 1j loading content of 13.68% with overall negative surface charge. Both the targeted and non-targeted nanoformulations were tested for their anticancer activities both in vitro and in vivo models, and found more effective as compared with free 1j treatment. However, the targeted nanoformulations showed higher therapeutic effect due to increased cellular internalization and caused mitochondria-dependent apoptosis in MCF-7 cells via oxidative stress. Besides, the targeted nanoformulation significantly inhibited in the development of solid tumor in comparison to non-targeted nanoformulations and free 1j as a consequence of increased internalization of the drug-candidate in tumor tissue. Therefore, this study proposes that 1j can be considered as a potent anti-carcinogenic compound in vivo and its therapeutic potential is further increased by using PBA functionalized and GN gated MSN-based controlled drug delivery system without showing any significant systemic toxicity.

Anticancer Potential of Temozolomide-Loaded Eudragit-Chitosan Coated Selenium Nanoparticles: In Vitro Evaluation of Cytotoxicity, Apoptosis and Gene Regulation

Resistance to temozolomide (TMZ) is the main cause of death in glioblastoma multiforme (GBM). The use of nanocarriers for drug delivery applications is one of the known approaches to overcome drug resistance. This study aimed to investigate the possible effect of selenium-chitosan nanoparticles loaded with TMZ on the efficacy of TMZ on the expression of MGMT, E2F6, and RELA genes and the rate of apoptosis in the C6 cell line. Selenium nanoparticles (SNPs) were loaded with TMZ and then they were coated by Eudragit® RS100 (Eud) and chitosan (CS) to prepare Se@TMZ/Eud-Cs. Physicochemical properties were determined by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDAX), thermal gravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS) methods. Se@TMZ/Eud-Cs was evaluated for loading and release of TMZ by spectrophotometric method. Subsequently, SNPs loaded with curcumin (as a fluorophore) were analyzed for in vitro uptake by C6 cells. Cytotoxicity and apoptosis assay were measured by MTT assay and Annexin-PI methods. Finally, real-time PCR was utilized to determine the expression of MGMT, E2F6, and RELA genes. Se@TMZ/Eud-Cs was prepared with an average size of 200 nm as confirmed by the DLS and microscopical methods. Se@TMZ/Eud-Cs presented 82.77 ± 5.30 loading efficiency with slow and pH-sensitive release kinetics. SNPs loaded with curcumin showed a better uptake performance by C6 cells compared with free curcumin (p-value < 0.01). Coated nanoparticles loaded with TMZ showed higher cytotoxicity, apoptosis (p-value < 0.0001), and down-regulation of MGMT, E2F6, and RELA and lower IC50 value (p-value < 0.0001) than free TMZ and control (p-value < 0.0001) groups. Using Cs as a targeting agent in Se@TMZ/Eud-Cs system improved the possibility for targeted drug delivery to C6 cells. This drug delivery system enhanced the apoptosis rate and decreased the expression of genes related to TMZ resistance. In conclusion, Se@TMZ/Eud-Cs may be an option for the enhancement of TMZ efficiency in GBM treatment.

Mesoporous Silica Nanoparticles: Properties and Strategies for Enhancing Clinical Effect

Due to the theragnostic potential of mesoporous silica nanoparticles (MSNs), these were extensively investigated as a novel approach to improve clinical outcomes. Boasting an impressive array of formulations and modifications, MSNs demonstrate significant in vivo efficacy when used to identify or treat myriad malignant diseases in preclinical models. As MSNs continue transitioning into clinical trials, a thorough understanding of the characteristics of effective MSNs is necessary. This review highlights recent discoveries and advances in MSN understanding and technology. Specific focus is given to cancer theragnostic approaches using MSNs. Characteristics of MSNs such as size, shape, and surface properties are discussed in relation to effective nanomedicine practice and projected clinical efficacy. Additionally, tumor-targeting options used with MSNs are presented with extensive discussion on active-targeting molecules. Methods for decreasing MSN toxicity, improving site-specific delivery, and controlling release of loaded molecules are further explained. Challenges facing the field and translation to clinical environments are presented alongside potential avenues for continuing investigations.

Folic acid-hydrophilic polymer coated mesoporous silica nanoparticles target doxorubicin delivery

Mesoporous silica nanoparticles (MSNs) gained significant attention, particularly in the pharmaceutical field. Folic acid (FA) shows marked promise as a targeting agent for its specific interaction with the folate receptor. This receptor is over-expressed on the cell surface of several cancerous cells like breast cancer. Polyethylene glycol (PE), as well as polypropylene glycol (PEG), is used to decorate nanoparticles to improve their biodistribution. Moreover, carboxymethyl beta-cyclodextrin (CM-β-CD), is used as a complexation molecule. In this study, we described the chemical synthesis, in vitro drug release and antiproliferative activity of doxorubicin-loaded/decorated MSNs further coupled with FA in two conditions: chemically bound or as a complex with CM-β-CD. Fourier Transform Infrared Spectroscopy with Transmission Electron Microscopy confirmed the successful surface change. Dynamic Light Scattering confirmed the change in surface characters like zeta potential, polydispersity index (PI), and size. PI improved from 0.58 to 0.23 while the size enlarged from 200 to 348 and 532 nm. Functionalized nanoparticles demonstrated more significant drug entrapment with (97%) while undecorated MSNs only showed (63%). Accordingly, we effectively synthesized FA-PEG2000-MSNs with IC₅₀: 0.015 mg/mL targeting HeLa cells. This approach may allow potential applications as a drug delivery system in cancer chemotherapy.HighlightsMesoporous silica nanoparticles (MSNs) with a carboxylic acid or amine surface group can be successfully decorated with long-chain hydrophilic polymer via an amide bond.Carboxymethyl-β-cyclodextrin coupled with long-chain polymer as host to form a complex with targeting molecule folic acid.Folic acid can be anchored directly to a polymer coat.TEM; DLS and FTIR confirmed the surface modification.The drug encapsulation efficiency; cytotoxicity and selectivity of functionalized nanoparticles with PEG and conjugated with FA were the best.Chemical modification has improved cytotoxicity of doxorubicin and selectivity against Hela cells.

Biomedical applications of methionine-based systems

Methionine (Met), an essential amino acid in the human body, possesses versatile features based on its chemical modification, cell metabolism and metabolic derivatives. Benefitting from its multifunctional properties, Met holds immense potential for biomedical applications. In this review, we systematically summarize the recent progress in Met-based strategies for biomedical applications. First, given the unique structural characteristics of Met, two chemical modification methods are briefly introduced. Subsequently, due to the disordered metabolic state of tumor cells, applications of Met in cancer treatment and diagnosis are summarized in detail. Furthermore, the efficacy of S-adenosylmethionine (SAM), as the most important metabolic derivative of Met, for treating liver diseases is mentioned. Finally, we analyze the current challenges and development trends of Met in the biomedical field, and suggest that Met-restriction therapy might be a promising approach to treat COVID-19.

An effective strategy for development of docetaxel encapsulated gold nanoformulations for treatment of prostate cancer

Nanoformulation based drug delivery is one of the most important research areas in the field of nanomedicine, which provides promising alternatives to the limitations of conventional chemotherapy. Nano drug delivery enables improved pharmacokinetic profile, bioavailability and therapeutic efficiency compared to the regular chemotherapeutic drugs. Herein, we have established a simple method for the synthesis of docetaxel (Dtx) encapsulated poly (ethylene glycol) (PEG) functionalized gold nanoparticles (AuNPs) for targeted drug delivery to prostate cancer. AuNPs were synthesized by the citrate ion reduction method followed by functionalization with thiol-PEG-amine (SH-PEG-NH2). SH-PEG-NH2 functionalized AuNPs were conjugated with the targeting vehicle, folic acid (FA). The anticancer drug, Dtx was encapsulated within AuNPs by the non-covalent linkage method. The physicochemical characteristics of the synthesized nanoformulations were extensively characterized by various spectral and microscopic studies. HR-TEM indicates the average size of the AuNPs is 16 nm and the nanoformulations is 18 nm. The encapsulation efficiency of the Dtx is ~ 96% which is confirmed by the elemental mapping analysis. The in vitro drug release profile of Dtx and AuNPs nanoformulations were studied by the dialysis membrane method. The anticancer activity of docetaxel encapsulated AuNPs were evaluated with prostate cancer cell lines (PC3). The drug encapsulated nanoformulations reduced the cell viability to about 40% (40 µM concentration at 24, 48 and 72 h of treatment). The optical microscopy observation reveals that the damage of prostate cancer cells after exposure to Dtx encapsulated AuNPs. The good cytotoxic activity of the present nanoformulation against prostate cancer cell lines enables its application for targeted drug delivery to prostate cancer.

Mesoporous silica nanoparticles combined with AKR1C3 siRNA inhibited the growth of castration-resistant prostate cancer by suppressing androgen synthesis in vitro and in vivo

Intracrine androgen synthesis plays a critical role in the development of castration-resistant prostate cancer (CRPC). Aldo-keto reductase family 1 member C3 (AKR1C3) is a vital enzyme in the intracrine androgen synthesis pathway. In this study, mesoporous silica nanoparticles (MSNs) were employed to deliver small interfering RNA targeting AKR1C3 (siAKR1C3) to downregulate AKR1C3 expression in CPRC cells. The optimal weight ratio of MSNs/siAKR1C3 was determined by a gel retardation assay. Prostate cancer cells such as VCaP cells, which intracrinally express AKR1C3, and LNCaP-AKR1C3 cells stably transfected with AKR1C3 were used to investigate the antitumour effect of MSNs-siAKR1C3. Fluorescence detection and Western blot analyses were applied to confirm the entrance of MSNs-siAKR1C3 into the cells. A SRB (Sulforhodamine B) assay was employed to assess the cell viability, and a radioimmunoassay was used to measure the androgen concentration. Moreover, real-time PCR (RT-PCR), Western blot analysis and ELISA were used to determine the transcription and expression of prostate-specific antigen (PSA), AKR1C3 and androgen receptor (AR). Meanwhile, a reporter gene assay was performed to determine the AR activity. Additionally, a castrated nude mouse xenograft tumour model was produced to verify the inhibitory effect of MSNs-siAKR1C3 in vivo. The results showed that the optimal weight ratio of MSNs/siAKR1C3 was 140:1, and the complex could effectively enter cells, downregulate AKR1C3 expression, reduce the androgen concentration, inhibit AR activation, and inhibit CRPC development both in vitro and in vivo. These results indicate that decreasing intracrine androgen synthesis and inactivating AR signals by MSNs-siAKR1C3 may be a potential effective method for CRPC treatment.

Design of Polymeric and Biocompatible Delivery Systems by Dissolving Mesoporous Silica Templates

There are many nanoencapsulation systems available today. Among all these, mesoporous silica particles (MSPs) have received great attention in the last few years. Their large surface-to-volume ratio, biocompatibility, and versatility allow the encapsulation of a wide variety of drugs inside their pores. However, their chemical instability in biological fluids is a handicap to program the precise release of the therapeutic compounds. Taking advantage of the dissolving capacity of silica, in this study, we generate hollow capsules using MSPs as transitory sacrificial templates. We show how, upon MSP coating with different polyelectrolytes or proteins, fully customized hollow shells can be produced. These capsules are biocompatible, flexible, and biodegradable, and can be decorated with nanoparticles or carbon nanotubes to endow the systems with supplementary intrinsic properties. We also fill the capsules with a fluorescent dye to demonstrate intracellular compound release. Finally, we document how fluorescent polymeric capsules are engulfed by cells, releasing their encapsulated agent during the first 96 h. In summary, here, we describe how to assemble a highly versatile encapsulation structure based on silica mesoporous cores that are completely removed from the final polymeric capsule system. These drug encapsulation systems are highly customizable and have great versatility as they can be made using silica cores of different sizes and multiple coatings. This provides capsules with unique programmable attributes that are fully customizable according to the specific needs of each disease or target tissue for the development of nanocarriers in personalized medicine.

Recent Nanocarrier Approaches for Targeted Drug Delivery in Cancer Therapy

Cancer is one of the most serious health concerns in the 21st century whose prevalence is beyond boundaries and can affect any organ of the human body. The conventional chemotherapeutic treatment strategies lack specificity to tumors and are associated with toxic effects on the immune system and other organ systems. In the past decades, there has been continuous progress in the development of smart nanocarrier systems for target-specific delivery of drugs against a variety of tumors, including intracellular gene-specific targeting. These nanocarriers are able to recognize the tumor cells and deliver the therapeutic agent in fixed proportions, causing no or very less harm to healthy cells. Nanosystems have modified physicochemical properties, improved bioavailability, and long retention in blood, which enhances their potency. A huge number of nanocarrier based formulations have been developed and are in clinical trials. Nanocarrier systems include polymeric micelles, liposomes, dendrimers, carbon nanotubes, gold nanoparticles, etc. Recent advancements in nanocarrier systems include mesoporous silica nanoparticles (MSNs), metal organic frameworks, and quantum dots. In the present review, various nanocarrier based drug delivery systems, along with their applications in the management of cancer, have been described with special emphasis on MSNs.

Multimodal Decorations of Mesoporous Silica Nanoparticles for Improved Cancer Therapy

The presence of leaky vasculature and the lack of lymphatic drainage of small structures by the solid tumors formulate nanoparticles as promising delivery vehicles in cancer therapy. In particular, among various nanoparticles, the mesoporous silica nanoparticles (MSN) exhibit numerous outstanding features, including mechanical thermal and chemical stability, huge surface area and ordered porous interior to store different anti-cancer therapeutics with high loading capacity and tunable release mechanisms. Furthermore, one can easily decorate the surface of MSN by attaching ligands for active targeting specifically to the cancer region exploiting overexpressed receptors. The controlled release of drugs to the disease site without any leakage to healthy tissues can be achieved by employing environment responsive gatekeepers for the end-capping of MSN. To achieve precise cancer chemotherapy, the most desired delivery system should possess high loading efficiency, site-specificity and capacity of controlled release. In this review we will focus on multimodal decorations of MSN, which is the most demanding ongoing approach related to MSN application in cancer therapy. Herein, we will report about the recently tried efforts for multimodal modifications of MSN, exploiting both the active targeting and stimuli responsive behavior simultaneously, along with individual targeted delivery and stimuli responsive cancer therapy using MSN.

Role of Folic Acid in the Therapeutic Action of Nanostructured Porous Silica Functionalized with Organotin(IV) Compounds Against Different Cancer Cell Lines

The synthesis, characterization and cytotoxic activity against different cancer cell lines of various mesoporous silica-based materials containing folate targeting moieties and a cytotoxic fragment based on a triphenyltin(IV) derivative have been studied. Two different mesoporous nanostructured silica systems have been used: firstly, micronic silica particles of the MSU-2 type and, secondly, mesoporous silica nanoparticles (MSNs) of about 80 nm. Both series of materials have been characterized by different methods, such as powder X-ray diffraction, X-ray fluorescence, absorption spectroscopy and microscopy. In addition, these systems have been tested against four different cancer cell lines, namely, OVCAR-3, DLD-1, A2780 and A431, in order to observe if the size of the silica-based systems and the quantity of incorporated folic acid influence their cytotoxic action. The results show that the materials are more active when the quantity of folic acid is higher, especially in those cells that overexpress folate receptors such as OVCAR-3 and DLD-1. In addition, the study of the potential modulation of the soluble folate receptor alpha (FOLR1) by treatment with the synthesized materials has been carried out using OVCAR-3, DLD-1, A2780 and A431 tumour cell lines. The results show that a relatively high concentration of folic acid functionalization of the nanostructured silica together with the incorporation of the cytotoxic tin fragment leads to an increase in the quantity of the soluble FOLR1 secreted by the tumour cells. In addition, the studies reported here show that this increase of the soluble FOLR1 occurs presumably by cutting the glycosyl-phosphatidylinositol anchor of membrane FR-α and by the release of intracellular FR-α. This study validates the potential use of a combination of mesoporous silica materials co-functionalized with folate targeting molecules and an organotin(IV) drug as a strategy for the therapeutic treatment of several cancer cells overexpressing folate receptors.

Nanotechnology-Based Strategies to Develop New Anticancer Therapies

The blooming of nanotechnology has made available a limitless landscape of solutions responding to crucial issues in many fields and, nowadays, a wide choice of nanotechnology-based strategies can be adopted to circumvent the limitations of conventional therapies for cancer. Herein, the current stage of nanotechnological applications for cancer management is summarized encompassing the core nanomaterials as well as the available chemical-physical approaches for their surface functionalization and drug ligands as possible therapeutic agents. The use of nanomaterials as vehicles to delivery various therapeutic substances is reported emphasizing advantages, such as the high drug loading, the enhancement of the pay-load half-life and bioavailability. Particular attention was dedicated to highlight the importance of nanomaterial intrinsic features. Indeed, the ability of combining the properties of the transported drug with the ones of the nano-sized carrier can lead to multifunctional theranostic tools. In this view, fluorescence of carbon quantum dots, optical properties of gold nanoparticle and superparamagnetism of iron oxide nanoparticles, are fundamental examples. Furthermore, smart anticancer devices can be developed by conjugating enzymes to nanoparticles, as in the case of bovine serum amine oxidase (BSAO) and gold nanoparticles. The present review is aimed at providing an overall vision on nanotechnological strategies to face the threat of human cancer, comprising opportunities and challenges.

Targeting drug delivery system for platinum(Ⅳ)-Based antitumor complexes

Classical platinum(II) anticancer agents are widely-used chemotherapeutic drugs in the clinic against a range of cancers. However, severe systemic toxicity and drug resistance have become the main obstacles which limit their application and effectiveness. Because divalent cisplatin analogues are easily destroyed in vivo, their bioavailability is low and no selective to tumor tissues. The platinum(IV) prodrugs are attractive compounds for cancer treatment because they have great advantages, e.g., higher stability in biological media, aqueous solubility and no cross-resistance with cisplatin, which may become the next generation of platinum anticancer drugs. In addition, platinum(IV) drugs could be taken orally, which could be more acceptable to cancer patients, breaking the current situation that platinum(II) drugs can only be given by injection. The coupling of platinum(IV) complexes with tumor targeting groups avoids the disadvantages such as instability in blood, irreversible binding to plasma proteins, rapid renal clearance, and non-specific distribution in normal tissues. Because of the above advantages, the combination of platinum complexes and tumor targeting groups has become the hottest field in the research and development of new platinum drugs. These approaches can be roughly categorized into two groups: active and passive targeted strategies. This review concentrates on various targeting and delivery strategies for platinum(IV) complexes to improve the efficacy and reduce the side effects of platinum-based anticancer drugs. We have made a summary of the related articles on platinum(IV) targeted delivery in recent years. We believe the results of the studies described in this review will provide new ideas and strategies for the development of platinum drugs.

New Advances in In Vivo Applications of Gated Mesoporous Silica as Drug Delivery Nanocarriers

One appealing concept in the field of hybrid materials is related to the design of gated materials. These materials are prepared in such a way that the release of chemical or biochemical species from voids of porous supports to a solution is triggered upon the application of external stimuli. Such gated materials are mainly composed of two subunits: i) a porous inorganic scaffold in which a cargo is stored, and ii) certain molecular or supramolecular entities, grafted onto the external surface, that can control mass transport from the interior of the pores. On the basis of this concept, a large number of examples are developed in the past ten years. A comprehensive overview of gated materials used in drug delivery applications in in vivo models from 2016 to date is thus given here.

Antimicrobial photodynamic therapy on Staphylococcus aureus and Escherichia coli using malachite green encapsulated mesoporous silica nanoparticles: an in vitro study

Background

Rise in the number of healthcare associated or hospital acquired infections is a major problem affecting the global healthcare sector. We evaluated superior antibacterial and antibiofilm photodynamic therapy (aPDT) using malachite green encapsulated mesoporous silica nanoparticles (MG-MSN) against Staphylococcus aureus and Escherichia coli, which are known to be major causative agents of nosocomial infections.

Methods

Malachite green (MG) was encapsulated on mesoporous silica nanoparticles (MSN). Fourier-transform infrared spectroscopy, Transmission electron microscopy, and spectroscopic analysis were performed to characterize the MG-MSN. The antimicrobial efficacies of MSN, MG, and MG-MSN were investigated and the results were recorded.

Results

MG-MSN was effective against both the tested bacteria. S. aureus was more phototoxic to MG-MSN compared to E. coli. The antibiofilm efficacy of MG-MSN on E. coli and S. aureus was also studied. Biofilm inhibition was 65.68 ± 2.62% in E. coli and 79.66 ± 3.82% in S. aureus. Cell viability assay, exopolysaccharides quantification, and confocal laser scanning microscopy studies also revealed the enhanced antibiofilm activity of MG-MSN when used as a potential photosensitizer for aPDT. This study can be extended to eradicate these strains from localized superficial infections and medical appliances, preventing nosocomial infections.

Silica-based nanosystems for therapeutic applications in the skin

Aging, exposure to oxidants, infectious pathogens, inflammogens, ultraviolet radiation and other environmental and genetic factors can result in the development of various skin disorders. Despite immense progress being made in dermatological treatments, many skin-associated problems still remain difficult to treat and various therapies have limitations. Progress in silica-based nanomaterials research provides an opportunity to overcome these drawbacks and improve therapies and is a promising tool for inclusion in clinical practice to treat skin diseases. This review focuses on the use of various types of silica nanoparticles with therapeutic applications in various skin disorders. These nanosystems improve treatment efficacy by maintaining or enhancing the effect of several drugs and are useful tools for nanomedicine, pharmaceutical sciences and future clinical applications.

Horizons of nanotechnology applications in female specific cancers

Female-specific cancers are the most common cancers in women worldwide. Early detection methods remain unavailable for most of these cancers, signifying that most of them are diagnosed at later stages. Furthermore, current treatment options for most female-specific cancers are surgery, radiation and chemotherapy. Although important milestones in molecularly targeted approaches have been achieved lately, current therapeutic strategies for female-specific cancers remain limited, ineffective and plagued by the emergence of chemoresistance, which aggravates prognosis. Recently, the application of nanotechnology to the medical field has allowed the development of novel nano-based approaches for the management and treatment of cancers, including female-specific cancers. These approaches promise to improve patient survival rates by reducing side effects, enabling selective delivery of drugs to tumor tissues and enhancing the uptake of therapeutic compounds, thus increasing anti-tumor activity. In this review, we focus on the application of nano-based technologies to the design of novel and innovative diagnostic and therapeutic strategies in the context of female-specific cancers, highlighting their potential uses and limitations.

Protein Corona over Mesoporous Silica Nanoparticles: Influence of the Pore Diameter on Competitive Adsorption and Application to Prostate Cancer Diagnostics

Diagnostic tests based on proteomics analysis can have significant advantages over more traditional biochemical tests. However, low molecular weight (MW) protein biomarkers are difficult to identify by standard mass spectrometric analysis, as they are usually present at low concentrations and are masked by more abundant resident proteins. We have previously shown that mesoporous silica nanoparticles are able to capture a predominantly low MW protein fraction from the serum, as compared to the protein corona (PC) adsorbed onto dense silica nanoparticles. In this study, we begin by further investigating this effect using liquid chromatography-mass spectrometry (LC-MS)/MS and thermogravimetric analysis (TGA) to compare the MW of the proteins in the coronas of mesoporous silica nanoparticles with the same particle size but different pore diameters. Next, we examine the process by which two proteins, one small and one large, adsorb onto these mesoporous silica nanoparticles to establish a theory of why the corona becomes enriched in low MW proteins. Finally, we use this information to develop a novel system for the diagnosis of prostate cancer. An elastic net statistical model was applied to LC-MS/MS protein coronas from the serum of 22 cancer patients, identifying proteins specific to each patient group. These studies help to explain why low MW proteins predominate in the coronas of mesoporous silica nanoparticles, and they illustrate the ability of this information to supplement more traditional diagnostic tests.

Controlled drug delivery systems for cancer based on mesoporous silica nanoparticles

The implementation of nanotechnology in medicine has opened new research horizons particularly in the field of therapeutic delivery. Mesoporous silica particles have emerged as biocompatible drug delivery systems with an enormous potential in the treatment of cancer among many other pathologies. In this review, we focus on the unique properties of these particles as chemotherapy delivery carriers. Here, we summarize the general characteristics of these nanomaterials - including their physicochemical properties and customizable surfaces - different stimuli that can be used to trigger targeted drug release, biocompatibility and finally, the drawbacks of these types of nanomaterials, highlighting some of the most important features of mesoporous silica nanoparticles in drug delivery.

Antimicrobial photodynamic activity of toluidine blue encapsulated in mesoporous silica nanoparticles against Pseudomonas aeruginosa and Staphylococcus aureus

In the present study, the antimicrobial and antibiofilm efficacy of toluidine blue (TB) encapsulated in mesoporous silica nanoparticles (MSN) was investigated against Pseudomonas aeruginosa and Staphylococcus aureus treated with antimicrobial photodynamic therapy (aPDT) using a red diode laser 670 nm wavelength, 97.65 J cm^-2 radiant exposure, 5 min). Physico-chemical techniques (UV-visible (UV-vis) absorption, photoluminescence emission, excitation, and FTIR) and high-resolution transmission electron microscopy (HR-TEM) were employed to characterize the conjugate of TB encapsulated in MSN (TB MSN). TB MSN showed maximum antimicrobial activities corresponding to 5.03 and 5.56 log CFU ml^-1 reductions against P. aeruginosa and S. aureus, respectively, whereas samples treated with TB alone showed 2.36 and 2.66 log CFU ml^-1 reductions. Anti-biofilm studies confirmed that TB MSN effectively inhibits biofilm formation and production of extracellular polymeric substances by P. aeruginosa and S. aureus.