Drug-loaded Mesoporous Silica Nanoparticles Research Articles

Remote-Controlled Activation of the Release through Drug-Loaded Magnetic Electrospun Fibers

The integration of magnetic nanoparticles within fibrillar structures represents an interesting avenue for the remotely controlled release of therapeutic agents. This work presents a novel drug release platform based on electrospun magnetic fibers (EMFs) combining drugs, magnetic nanoparticles (MNPs) and mesoporous silica nanoparticles (MSNs) for controlled drug delivery via alternating magnetic fields (AMF). The platform was demonstrated to be versatile and effective for hydrophilic ketorolac (KET) and hydrophobic curcumin (CUR) encapsulation and the major response observed for AMF-triggered release was reached using drug-loaded MSNs within the fibers, providing fine control over drug release patterns. The EMFs exhibited excellent inductive heating capabilities, showing a temperature increase of ∆T up to 8 °C within a 5 min AMF pulse. The system is shown to be promising for applications like transdermal pain management, oncological drug delivery, tissue engineering, and wound healing, enabling precise control over drug release in both spatial and temporal dimensions. The findings of this study offer valuable insights into the development of the next generation of smart drug delivery systems, based in multifunctional materials that can be remotely regulated and potentially revolutionize the field of nanomedicine.

Drug-Loaded Mesoporous Silica Nanoparticles Enhance Antitumor Immunotherapy by Regulating MDSCs.

Myeloid-derived suppressor cells (MDSCs) are recognized as major immune suppressor cells in the tumor microenvironment that may inhibit immune checkpoint blockade (ICB) therapy. Here, we developed a Stattic-loaded mesoporous silica nanoparticle (PEG-MSN-Stattic) delivery system to tumor sites to reduce the number of MDSCs in tumors. This approach is able to significantly deplete intratumoral MSDCs and thereby increase the infiltration of T lymphocytes in tumors to enhance ICB therapy. Our approach may provide a drug delivery strategy for regulating the tumor microenvironment and enhancing cancer immunotherapy efficacy.

Contact Lens with pH Sensitivity for On-Demand Drug Release in Wearing Situation.

Drug-releasing contact lenses are emerging therapeutic systems for treating ocular diseases. However, their applicability is limited by the burst release of drugs during lens wear and premature drug leakage during packaging, rendering the precise control of release duration or dose difficult. Here, we introduce a pH-sensitive contact lens exhibiting on-demand drug release only during lens wear and negligible premature drug leakage during packaging and transportation, which is accomplished by incorporating drug-loaded mesoporous silica nanoparticles (MSNs) coated with a pH-sensitive polymer into the contact lens. The compositionally optimized pH-sensitive polymer has a lower critical solution temperature (LCST) at >45 °C at pH 7.4, whereas its LCST decreases to <35 °C under acidic conditions (pH ∼ 6.5). Consequently, the MSN-incorporated contact lens sustainably releases the loaded drugs only in the acidic state at 35 °C, which corresponds to lens-wear conditions, through the MSN pores that open because of the shrinkage of polymer chains. Conversely, negligible drug leakage is observed from the contact lens under low-temperature or neutral-pH conditions corresponding to packaging and transportation. Furthermore, compared with the plain contact lens, the pH-sensitive contact lens exhibits good biocompatibility and unchanged bulk characteristics, such as optical (transmittance in the visible-light region), mechanical (elastic modulus and tensile strength), and physical (surface roughness, oxygen permeability, and water content) properties. These findings suggest that the pH-sensitive contact lens can be potentially applied in ocular disease treatment.

Ultrasound-Responsive Biomimetic Superhydrophobic Drug-Loaded Mesoporous Silica Nanoparticles for Treating Prostate Tumor.

Interfacial nanobubbles on a superhydrophobic surface can serve as ultrasound cavitation nuclei for continuously promoting sonodynamic therapy, but their poor dispersibility in blood has limited their biomedical application. In this study, we proposed ultrasound-responsive biomimetic superhydrophobic mesoporous silica nanoparticles, modified with red blood cell membrane and loaded with doxorubicin (DOX) (F-MSN-DOX@RBC), for RM-1 tumor sonodynamic therapy. Their mean size and zeta potentials were 232 ± 78.8 nm and -35.57 ± 0.74 mV, respectively. The F-MSN-DOX@RBC accumulation in a tumor was significantly higher than in the control group, and the spleen uptake of F-MSN-DOX@RBC was significantly reduced in comparison to that of the F-MSN-DOX group. Moreover, the cavitation caused by a single dose of F-MSN-DOX@RBC combined with multiple ultrasounds provided continuous sonodynamic therapy. The tumor inhibition rates in the experimental group were 71.5 8 ± 9.54%, which is significantly better than the control group. DHE and CD31 fluorescence staining was used to assess the reactive oxygen species (ROS) generated and the broken tumor vascular system induced by ultrasound. Finally, we can conclude that the combination of anti-vascular therapy, sonodynamic therapy by ROS, and chemotherapy promoted tumor treatment efficacy. The use of red blood cell membrane-modified superhydrophobic silica nanoparticles is a promising strategy in designing ultrasound-responsive nanoparticles to promote drug-release.

Peptide functionalized nanocarriers for targeted drug delivery in cancer therapy.

The intrinsic limitations of conventional cancer therapies have prompted the development of nanocarriers for more effective and safer cancer treatment. Amongst these, nanocarriers functionalized with tumor-targeting moieties have been utilized to enhance delivery of cancer therapeutics. However, recent reports have revealed that only a modest increase in tumor targeting is typically achieved with this approach. Poor tumor accumulation is largely due to formation of a serum protein corona on the surface of the nanocarriers in circulation, which hinders targeting and leads to nonspecific tissue distribution, immune recognition and rapid blood clearance. Here, we present three highly efficient tumor-targeting nanocarriers that overcome the aforementioned issues. These nanocarriers are functionalized with the acidity-triggered rational membrane (ATRAM) peptide that facilitates internalization specifically into cancer cells within the acidic tumor microenvironment. The first system is a hybrid nanocarrier that consists of a drug-loaded polylactic-co-glycolic acid (PLGA) core covalently ‘wrapped’ with a crosslinked bovine serum albumin (BSA) shell. Second are upconversion mesoporous silica nanospheres (UMSNs), with combined photodynamic therapy, photothermal therapy and imaging capabilities, that consist of a lanthanide-doped core ‘wrapped’ with lipid-polyethylene glycol (DSPE-PEG-maleimide). The final system consists of drug-loaded mesoporous silica nanoparticles (MSNs) coated with a lipid bilayer composed of DPPC/Chol/DSPE-PEG-mal. The lipid coat is then functionalized with programmed death receptor ligand-1 antibody (anti-PD-L1 antibody, atezolizumab) to disrupt the programmed death 1 (PD-1) interaction that inhibits the anticancer activity of tumor-infiltrating immune cells. In all three systems, the BSA or lipid coats serve to minimize interactions with serum proteins, which allows the nanocarriers to evade immune recognition and extends the in vivo circulation half-life. All three systems exhibit remarkable tumor-targeting efficiency leading to highly potent anticancer activity, while exhibiting negligible toxicity to healthy tissue. Thus, all three systems represent highly promising nanoplatforms for the targeted delivery of cancer therapeutics.

Designing robust xylan/chitosan composite shells around drug-loaded MSNs: Stability in upper GIT and degradation in the colon microbiota

Long residence times, near-neutral pH values, and release triggered by the enzymatic action of the resident microbiota offer unique opportunities for improved drug delivery in the colon. The fact that a delivery agent must also pass through the complete GI tract without degradation presents a challenge due to widely changing pH conditions. In this study, a promising colon-targeted drug delivery system was composed of a xylan/chitosan composite shell formed on curcumin-loaded mesoporous silica nanoparticles (MSNs). A novel synthesis approach was employed to facilitate precipitation of negatively charged xylan on negatively charged MSNs by concurrent chitosan polymerization. Curcumin-loaded xylan/chitosan-coated MSNs (C-MSNs) were determined to contain nearly 42% xylan by the inclusion of chitosan in a one-to-one ratio with xylan. The xylan/chitosan composite shell demonstrated excellent stability in the acidic upper GI tract. The hydrolysis of glycosidic bonds by resident microbiota was the triggering mechanism for xylan degradation and curcumin release in the colon. The presence of xylan has the further benefit of increasing the number of beneficial bacteria and improving short-chain fatty acid production for improved colon health.

Abstract 10189: A Novel Hypothermia-Triggered and Controlled-Release Hydrogen Sulfide Delivery System Exerts Myocardial Protection from Ischemia-Reperfusion Injury

Introduction: Hydrogen sulfide is a cardio-protective gas molecule, which prevents cardiocytes from ischemia-reperfusion injury, and then further improves the transplanted heart performance. However, the instability of hydrogen sulfide restricts its application in cryogenic heart reserving solution. The present study aimed to construct a novel hypothermia-triggered mesoporous silica nanoparticles (HT-MSN) for controlled hydrogen sulfide release. Methods: A polymer as hypothermia trigger was synthesized through free radical copolymerization of N-n-propylacrylamide and N-tert-butylacrylamide with azodiisobutyronitrile as the initiator. The selected diallyl trisulfide, as the hydrogen sulfide donor, was encased in mesoporous silica nanoparticles (MSN) to obtain controlled-release and drug-loaded particles. In order to controllably release hydrogen sulfide from drug-loaded particles in hypothermia, the polymers were coated on the surface of drug-loaded MSN. Characteristics of obtained HT-MSN were evaluated. Cytotoxicity and effects on myocardial protection were further assessed. Results: Combination of nuclear magnetic resonance spectroscopy and gel permeation chromatography determined the synthesized success of the hypothermia-triggered polymer. Further, through adjusting composition of those co-monomers, the polymer showed a lower critical solution temperature of around 7 o C estimated by ultraviolet, indicting the potential for application at lower temperatures. Transmission electron microscope identified characteristics of obtained HT-MSN with uniform size and regular mesoporous. Furthermore, the novel HT-MSN system exhibited low cytotoxicity and acceptable myocardial protection, including anti-apoptosis and antioxidant activities. Conclusion: This study provided a novel hypothermia-triggered platform for controlled hydrogen sulfide release to protect cardiocytes against ischemia-reperfusion injury.

Differently sized drug-loaded mesoporous silica nanoparticles elicit differential gene expression in MCF-7 cancer cells.

Aim: This study investigates the effects of different sized unmodified and chemo-responsive mesoporous silica nanocarriers on MCF-7 cancer cells. Materials & methods: Unmodified and thiol-functionalized large and small-sized mesoporous MCM-41 silica nanoparticles prepared using templated sol-gel process were characterized for their physicochemical properties and in vitro and in vivo anticancer efficacy. Microarray analysis was carried out to assess their differential effect on gene expression. Results: Thiol-functionalized nanoparticles displayed chemo responsive release and greater cytotoxicity to cancer cells when compared with unmodified carriers. Microarray studies showed distinct differences in genes differentially regulated by sMCM-41and lMCM-41 carriers when compared with the free drug. Conclusion: The small chemo-responsive carrier was more effective in suppressing oncogenes and genes involved in proliferation, invasion and survival while the large carrier mainly altered membrane-associated pathways.

Stabilized amorphous state of riluzole by immersion-rotavapor method with synthesized mesoporous SBA-15 carrier to augment in-vitro dissolution

Mesoporous silica nanoparticles (MSNs) carriers have been considered as a promising approach for stabilizing the amorphous state of loaded drugs. MSNs are significantly improving the dissolution rate of poorly soluble drug candidates. The purpose of this study was to improve the rate of dissolution of the poorly water-soluble drug riluzole via amalgamation into Santa Barbara Amorphous type material (SBA-15) materials. A novel formulation is processed via the immersion-rotavapor method for riluzole (RLZ) with mesoporous SBA-15 submicron particles. The drug-loaded mesoporous silica nanoparticles were assessed by different characterization methods: scanning electron microscopy and differential scanning calorimetry. RLZ/SBA-15 unveiled superiority in the production of stable amorphous RLZ with a significantly enhanced rate of dissolution. Most drug molecules were entrapped, with drug loading of RLZ/SBA-15 ratio being 1:1 (w/w), inside the mesoporous channels via the immersion-rotavapor method. RLZ confined inside the mesoporous structure was in the amorphous state shown by DSC measurements. The uniform pore walls were thought to avert the recrystallization of the homogeneously distributed drug molecules inside the mesoporous structure. Remarkably, SBA-15 released the RLZ around 98.51 ± 2.01% in 8 h, whereas RLZ crystal showed only the dissolution of 39.57%. The dissolution rate of RLZ from the SBA-15 matrix was significantly improved. Henceforth, SBA-15 may become a capable platform for improving the RLZ oral bioavailability.

Targeting laryngeal cancer cells with 5-fluorouracil and curcumin using mesoporous silica nanoparticles.

Objective:To explore the inhibitory and synergistic effects of 5-fluorouracil and curcumin on Hep-2 laryngeal cancer cells and clarify the effect of mesoporous silica nanoparticles as drug carriers.Methods:The inhibitory effects of 5-fluorouracil and curcumin on Hep-2 cells were detected using the CCK-8 assay. CompuSyn was used to calculate the synergistic effect of the 2 drugs. Flow cytometry was used to detect apoptosis and cell cycle arrest induced by 5-fluorouracil and curcumin. The drugs were loaded into mesoporous nanoparticles. Western blotting was used to detect the expression of related proteins after treatment. The growth of subcutaneous tumors in BALB/c nude after the intraperitoneal injection with drug-loaded mesoporous silica nanoparticles was recorded.Results:5-Fluorouracil and curcumin synergistically induced apoptosis and cell cycle arrest in Hep-2 cells. Mesoporous silica nanoparticles as drug carriers enhanced the therapeutic effects of 5-fluorouracil and curcumin.Conclusions:Mesoporous silica nanoparticles are expected to be effective drug carriers that enhance the synergistic effects of 5-fluorouracil and curcumin on laryngeal cancer.

Superhydrophobic drug-loaded mesoporous silica nanoparticles capped with β-cyclodextrin for ultrasound image-guided combined antivascular and chemo-sonodynamic therapy

Interfacial nanobubbles (INBs) on a superhydrophobic surface has been proposed as a solid cavitation agent for enhancing inertial cavitation dose and ultrasound contrast imaging, but the dispersibility of superhydrophobic particles limits the biomedical application. For this study, we designed superhydrophobic mesoporous silica nanoparticles loaded with the anti-tumor drug Doxorubicin (FMSNs-Dox) for tumor therapy. The β-cyclodextrin was used to cap the superhydrophobic surface of FMSNs-Dox to reduce aggregation without inhibiting the accumulation of INBs. The mean size and a contact angle of FMSNs-Dox was 217 ± 58 nm and 129 ± 3°, respectively. The INBs cavitation on the surface of FMSNs-Dox during ultrasound sonication disrupted tumor vessels to allow a large amount of drug penetrating and trapping within tumors. The reduced tumor perfusion, histological reactive oxygen species staining, and tumor inhibition demonstrated that FMSNs-Dox sonication combined anti-vascular, sonodynamic and chemical therapies in a simple platform. Moreover, the repeatability of INB cavitation by single-injection FMSNs-Dox with multiple ultrasound sonication provided intratumoral ultrasound contrast-enhanced imaging from day 1–9 (enhancement of 3.84 ± 0.47 dB). Therefore, the characteristics of FMSNs-Dox with slow biodegradation and acoustic-sensitivity presented intratumoral day-scaled lifetime to provide a probability of repeated combination therapy by single-injection.

Amino-decorated mesoporous silica nanoparticles for controlled sofosbuvir delivery

The present study describes synthesis of amino-decorated mesoporous silica nanoparticles (MSNs) for sustained delivery and enhanced bioavailability of sofosbuvir. Sofosbuvir is active against hepatitis C virus and pharmaceutically classified as class III drug according to biopharmaceutics classification system (BCS). MSNs were synthesized using modified sol-gel method and the surface was decorated with amino functionalization. Drug loaded MSNs were also grafted with polyvinyl alcohol in order to compare it with the amino-decorated MSNs for sustained drug release. The prepared MSNs were extensively characterized and the optimized formulation was toxicologically and pharmacokinetically evaluated. The functionalized MSNs of 196 nm size entrapped 29.13% sofosbuvir in the pores, which was also confirmed by the decrease in surface area, pore volume and pore size. The drug-loaded amino-decorated MSNs revealed an improved thermal stability as confirmed by thermal analysis. Amino-decorated MSNs exhibited Fickian diffusion controlled sofosbuvir release as compared with non-functionalized and PVA grafted MSNs. Amino-decorated MSNs were deemed safe to use in Sprague-Dawley rats after 14-days exposure as confirmed by the toxicological studies. More interestingly, we achieved a 2-fold higher bioavailability of sofosbuvir in Sprague-Dawley rats in comparison with sofosbuvir alone, and the Tmax was delayed 3-times indicating a sustained release of sofosbuvir.

Direct preparation of drug-loaded mesoporous silica nanoparticles by sequential flash nanoprecipitation

The present work demonstrates how drug-loaded mesoporous silica nanoparticles (MSNPs) can be prepared by a sequential flash nanoprecipitation (FNP) technique. A sequential FNP technique is developed relying on a combination of two multi-inlet vortex mixers (MIVM), by which a continuous process that involves the formation of micelle-based templates followed by an in situ formation of MSNPs is achieved. Moreover, a widely used biological nematicide, abamectin (Abm), is added during the formation of micelles, ultimately leading to Abm-loaded MSNPs with high encapsulation efficiency. The obtained Abm-loaded MSNPs show excellent stability and inhibition activity against the livability of Meloidogyne incognita. Importantly, the parameters of the resulting MSNPs, such as silica shell thickness and inner cavity size of MSNPs, can be easily controlled by tuning the compositions of the reactant streams. We believe that such a simple approach towards direct preparation of drug-loaded MSNPs would find promising up-scale applications in various fields, such as drug delivery, bioimaging, and formulation technology.

Functionalised mesoporous silica nanoparticles with excellent cytotoxicity against various cancer cells for pH-responsive and controlled drug delivery

Mesoporous silica nanoparticles (MSNs) modified with Pt and carboxyl groups were designed and the drug molecule-release behaviour was studied by loading cisplatin as a model anticancer drug. The MSNs had a high surface area (342 m2 g−1) and dual pores (3.3 and 33.4 nm) with a uniform size. The amount of cisplatin loaded in the nanopores was 74.9 mg g−1. Drug release was approximately two times higher under acidic conditions (pH 4.0) than under neutral conditions (pH 7.3). The cell viability was tested using three types of cancer cells (A549, A2780, and MCF-7). When the drug-free samples (Surfactant-extracted MSNs, COOH-MSNs) were applied at a concentration of 500 μg ml−1, the cancer cell death did not show any differences (Cell survival rate of approximately 82.7–85.7%). On the other hand, cancer cell death was more pronounced with excellent performance when drug-loaded MSNs (Pt/COOH-MSNs) were applied at the same concentration (Cell survival rate 3.6% for A549, 15.8% for A2780, 12.8% for MCF-7, respectively). This result may give more generalised insights in developing effective and universal nanocarrier of an anticancer drug by using multiple cell lines instead of using any single cancer cell line.

Cancer cell membrane as gate keeper of mesoporous silica nanoparticles and photothermal-triggered membrane fusion to release the encapsulated anticancer drug

The cancer cell membrane (CCM) is widely used for nanomedicine encapsulation to improve their tumor-targeting ability. However, few researches are focused on drug release process and mechanism of these composite. Cell membrane fusion (two separate lipid membranes merge into a single continuous bilayer), one of the most fundamental processes in biology could be promoted by heating. Thus, in this manuscript, CCM was exploited as the gate keeper and tumor-targeting moiety of anticancer drug-loaded mesoporous silica nanoparticles (MSN). In addition, the drug release process and mechanism based on cell membrane fusion were studied. The loaded drugs included indocyanine green (ICG), a FDA-approved near-infrared photothermal agent for clinical applications, and doxorubicin (DOX), a chemotherapy drug. By coating CCM on drug-loaded MSN, the keeper could prevent unexpected drug leaking during the circulation and provide tumor targeting based on its specific recognition function. After arriving tumor tissue post-tail vein injection, the tumor position is irradiated by 808 nm light to trigger light–thermal conversion process of ICG to heat the composite (DOX-ICG@MSN@CCM) and promote cell membrane fusion between the encapsulated CCM and targeted tumor cell membrane. Such process can enhance the uptake efficacy of DOX-ICG@MSN@CCM to tumor cells. Furthermore, ICG could provide a synergistic photothermal therapy activity with DOX.

Hypersound-Enhanced Intracellular Delivery of Drug-Loaded Mesoporous Silica Nanoparticles in a Non-Endosomal Pathway.

The intracellular delivery efficiency of drug-loaded nanocarriers is often limited by biological barriers arising from the plasma membrane and the cell interior. In this work, the entering of doxorubicin (Dox)-loaded mesoporous silica nanoparticles (MSNs) into the cytoplasm was acoustically enhanced through direct penetration with the assistance of hypersound of gigahertz (GHz) frequency. Both fluorescence and cell viability measurements revealed that the therapeutic efficacy of Dox-loaded MSNs was significantly improved by tuning the power and duration of hypersound on demand with a nanoelectromechanical resonator. Mechanism studies with inhibitors illustrated that the membrane defects induced by the hypersound-triggered GHz acoustic streaming facilitated the Dox-loaded MSNs of 100-200 nm to directly penetrate through the cell membrane instead of via the traditional endocytosis, which highly increased the delivery efficiency by avoiding the formation of endosomes. This acoustic method enables the drug carriers to overcome biological barriers of the cell membrane and the endosomes without the limitation of carrier materials, which provides a versatile way of enhanced drug delivery for biomedical applications.

A self-targeting and controllable drug delivery system constituting mesoporous silica nanoparticles fabricated with a multi-stimuli responsive chitosan-based thin film layer

Surface modification and functionalization of nanomaterials have been adopted widely in devising smart drug delivery systems. This work examines the fabrication of multi-stimuli responsive surfaces on mesoporous silica nanoparticles (MSN) for environmentally sensitive site specific drug delivery with reduced risk of premature drug leakage. Chitosan cross-linked via disulfide bonds was applied to form a thin film on drug-loaded MSN, realizing a capsulation and stimuli-sensitive regulating gate membrane; that was further conjugated with folate for site specific targeting toward cancer cells. The chitosan thin film was very stable under neutral conditions and could effectively prevent drug leakage, but was sensitive to both pH and GSH stimulations to reach rapid drug release. Thus, drug release could be triggered by changes in such factors that are common to cancer cells. However, complete and accelerated release could only be realized when triggered simultaneously by both acidic pH and GSH. Moreover, tests with HepG-2 cells confirmed that folate-receptor mediated endocytosis successfully enhanced the cellular uptake of the nanoparticle and antitumor activity toward cancer cells. It is expected that this surface chemical modification strategy promises a powerful approach constructing smart drug delivery systems for efficient and safe chemotherapy.

MCM-41 Nanoparticles for Brain Delivery: Better Choline-Esterase and Amyloid Formation Inhibition with Improved Kinetics

The present study was aimed at delivering a low bioavailability drug, rivastigmine hydrogen tartrate (RTG), to the brain through its encapsulation in mesoporous silica nanoparticles (MSNs) and targeted to amyloid inhibition in the brain. MSNs were characterized for size, zeta potential, and drug entrapment using SEM, TEM, HR-TEM, FT-IR, and PXRD. Drug-loaded MSNs were assessed for in vitro release kinetics and ex vivo followed by animal studies. The average size of the prepared blank (MCM-41B) and drug-loaded MSNs (MCM-41L) was 114 ± 2.0 and 145 ± 0.4 nm with the zeta potential of approximately -43.5 ± 1.1 and -37.6 ± 1.4 mV, respectively. MCM-41L exhibited an average entrapment efficiency of 88%. In vitro release studies exhibited early surge followed by a sluggish persistent or constant release (biphasic pattern). Hemolytic studies proved that the developed MCM-41L NPs are less hemolytic compared to RTG. A reduced ThT fluorescence was observed with MCM-41L compared to MCM-41B and RTG in the amyloid inhibition studies. A significant (p < 0.05) inhibition of AChE (acetycholinesterase) was observed for MCM-41L (80 ± 4.98%), RTG (62 ± 3.25%), and MCM-41B (54 ± 4.25%). In vivo pharmacokinetics in Wistar rats revealed that the AUC and mean residence time (MRT) for MCM-41L was sustained and significantly higher (p < 0.05) (780 ± 3.30 ng/L; 5.49 ± 0.25 h) compared to RTG solution (430 ± 3.50 ng/L; 0.768 ± 0.17 h). Similarly, the half-life was found to be significantly higher in case of MCM-41L. The promising result was brain delivery of RTG in Wistar rats which was enhanced almost 127 folds in vivo, using MCM-41L nanoparticles. MCM-41L nanoparticles effectively enhanced the bioavailability of RTG. Conclusively, these can be used for the administration of RTG and other related low bioavailability drugs for improved brain delivery.

Augmented Anticancer Efficacy by si-RNA Complexed Drug-Loaded Mesoporous Silica Nanoparticles in Lung Cancer Therapy

Lung cancer remains the major cause of death throughout the world. However, with the cutting-edge therapeutic approaches the patient’s survivability remains poor. Nanoparticle-mediated targeted gene therapy has surfaced globally for the therapeutic improvement in cancer patients. Recently, mesoporous silica nanoparticles (MSNs) have attracted much attention for the intracellular delivery of siRNA. Further codelivery strategy has been proposed to minimize the amount of each drug and to achieve the synergistic effect for cancer therapies. In the present investigation we explored the efficacy of codelivery of anticancer drugs along with survivin siRNA in the MSNs for a comparative therapeutic efficacy in lung cancer. Our results revealed such combinational approach has provoked enhanced therapeutic efficacy by synergistic drug activity while restraining the action of survivin protein. Thus, we anticipate this emerging approach may be quite beneficial for lung cancer therapy in future.

Chemotaxis‐Guided Hybrid Neutrophil Micromotors for Targeted Drug Transport

Engineering self-propelled micromotors with good biocompatibility and biodegradability for actively seeking disease sites and targeted drug transport remains a huge challenge. In this study, neutrophils with intrinsic chemotaxis capability were transformed into self-guided hybrid micromotors by integrating mesoporous silica nanoparticles (MSNs) with high loading capability. To ensure the compatibility of neutrophil cells with drug-loaded MSNs, bacteria membranes derived from E. coli were coated on MSNs in advance by a camouflaging strategy. The resulting biohybrid micromotors inherited the characteristic chemotaxis capability of native neutrophils and could effectively move along the chemoattractant gradients produced by E. coli. Our studies suggest that this camouflaging approach, which favors the uptake of MSNs into neutrophils without loss of cellular activity and motility, could be used to construct synthetic nanoparticle-loaded biohybrid micromotors for advanced biomedical applications.