Glucosamine-Modified Mesoporous Silica-Coated Magnetic Nanoparticles: A "Raisin-Cake"-like Structure as an Efficient Theranostic Platform for Targeted Methotrexate Delivery.

This study presents the synthesis of glucosamine-modified mesoporous silica-coated magnetic nanoparticles (MNPs) as a therapeutic platform for the delivery of an anticancer drug, methotrexate (MTX). The MNPs were coated with mesoporous silica in a templated sol-gel process to form MNP@MSN, and then chloropropyl groups were added to the structure in a post-modification reaction. Glucosamine was then reacted with the chloro-modified structure, and methotrexate was conjugated to the hydroxyl group of the glucose. The prepared structure was characterized using techniques such as Fourier transform infrared (FT-IR) spectroscopy, elemental analysis (CHN), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), a vibrating sample magnetometer (VSM), and X-ray diffraction (XRD). Good formation of nano-sized MNPs and MNP@MSN was observed via particle size monitoring. The modified glucosamine structure showed a controlled release profile of methotrexate in simulated tumor fluid. In vitro evaluation using the 4T1 breast cancer cell line showed the cytotoxicity, apoptosis, and cell cycle effects of methotrexate. The MTT assay showed comparable toxicity between MTX-loaded nanoparticles and free MTX. The structure could act as a glucose transporter-targeting agent and showed increased uptake in cancer cells. An in vivo breast cancer model was established in BALB/C mice, and the distribution of MTX-conjugated MNP@MSN particles was visualized using MRI. The MTX-conjugated particles showed significant anti-tumor potential together with MRI contrast enhancement.

The Current Landscape of Glioblastoma Biomarkers in Body Fluids.

Glioblastoma (GBM) is a highly aggressive and lethal primary brain cancer that necessitates early detection and accurate diagnosis for effective treatment and improved patient outcomes. Traditional diagnostic methods, such as imaging techniques and tissue biopsies, have limitations in providing real-time information and distinguishing treatment-related changes from tumor progression. Liquid biopsies, used to analyze biomarkers in body fluids, offer a non-invasive and dynamic approach to detecting and monitoring GBM. This article provides an overview of GBM biomarkers in body fluids, including circulating tumor cells (CTCs), cell-free DNA (cfDNA), cell-free RNA (cfRNA), microRNA (miRNA), and extracellular vesicles. It explores the clinical utility of these biomarkers for GBM detection, monitoring, and prognosis. Challenges and limitations in implementing liquid biopsy strategies in clinical practice are also discussed. The article highlights the potential of liquid biopsies as valuable tools for personalized GBM management but underscores the need for standardized protocols and further research to optimize their clinical utility.

Biomaterial-based delivery platforms for transdermal immunotherapy.

Nowadays, immunotherapy is one of the most essential treatments for various diseases and a broad spectrum of disorders are assumed to be treated by altering the function of the immune system. For this reason, immunotherapy has attracted a great deal of attention and numerous studies on different approaches for immunotherapies have been investigated, using multiple biomaterials and carriers, from nanoparticles (NPs) to microneedles (MNs). In this review, the immunotherapy strategies, biomaterials, devices, and diseases supposed to be treated by immunotherapeutic strategies are reviewed. Several transdermal therapeutic methods, including semisolids, skin patches, chemical, and physical skin penetration enhancers, are discussed. MNs are the most frequent devices implemented in transdermal immunotherapy of cancers (e.g., melanoma, squamous cell carcinoma, cervical, and breast cancer), infectious (e.g., COVID-19), allergic and autoimmune disorders (e.g., Duchenne's muscular dystrophy and Pollinosis). The biomaterials used in transdermal immunotherapy vary in shape, size, and sensitivity to external stimuli (e.g., magnetic field, photo, redox, pH, thermal, and even multi-stimuli-responsive) were reported. Correspondingly, vesicle-based NPs, including niosomes, transferosomes, ethosomes, microemulsions, transfersomes, and exosomes, are also discussed. In addition, transdermal immunotherapy using vaccines has been reviewed for Ebola, Neisseria gonorrhoeae, Hepatitis B virus, Influenza virus, respiratory syncytial virus, Hand-foot-and-mouth disease, and Tetanus.

Repurposing of sevelamer as a novel antidote against aluminum phosphide poisoning: An in vivo evaluation.

Aluminum phosphide (AlP) is widely used for protecting grains from pests. AlP releases toxic phosphine gas (PH3) while exposed to humidity. Poisoning with these tablets is dangerous and can cause death or serious injuries. Up to now, no definite antidote has been introduced for specific treatment of this poisoning. Sevelamer carbonate or sevelamer hydrochloride (Renagel) is a polymeric pharmaceutical prescribed for treating hyperphosphatemia in patients with chronic kidney disease. Sevelamer can bind with phosphate groups and act as an anion exchanger. Herein, sevelamer is repurposed as a potent antidote agent in phosphine gas poisoning. In vivo evaluation was conducted on male Sprague Dawley rats. The evaluation was conducted on three groups of animals: control, AlP-poisoned, and AlP-poisoned treated with sevelamer. Survival percentage, serum biomarkers level of organ injury, and ATP level were recorded. The results indicate a high survival rate in sevelamer-treated animals compared with the AlP-poisoned group (75% vs. 0% respectively, 48 h after poisoning). The analysis of serum markers of organ injury also showed that sevelamer could reduce toxicity and organ injury in poisoned animals. ATP level of separate organs showed that sevelamer treated groups were recovered. The results showed that sevelamer could be a potent antidote for managing aluminum phosphide poisoning. Moreover, a mechanism is suggested for the interaction of sevelamer with phosphine gas.

The inhibitory effect of curcumin loaded poly (vinyl caprolactam) nanohydrogel on insulin fibrillation.

Amyloidosis refers to a group of diseases caused by the deposition of abnormal proteins in tissues. Herein, curcumin was loaded in a nanohydrogel made of poly (vinylcaprolactam) to improve its solubility and was employed to exert an inhibitory effect on insulin fibrillation, as a protein model. Poly (vinyl caprolactam), cross-linked with polyethylene glycol diacrylate, was synthesized by the reversible addition-fragmentation chain transfer method. The release profile of curcumin exhibited a first-order kinetic model, signifying that the release of curcumin was mainly dominated by diffusion processes. The study of curcumin release showed that 78% of the compound was released within 72 h. The results also revealed a significant decline in insulin fibrillation in the presence of curcumin-loaded poly (vinyl caprolactam). These observations confirmed that increasing the ratio of curcumin-loaded poly (vinyl caprolactam) to insulin concentration would increase the hydrogel's inhibitory effect (P-value < 0.05). Furthermore, transmission electron and fluorescence microscopies and Fourier-transform infrared spectroscopy made it possible to study the size and interaction of fibrils. Based on the results, this nanohydrogel combination could protect the structure of insulin and had a deterrent effect on fibril formation.

pH-responsive glycodendrimer as a new active targeting agent for doxorubicin delivery.

The present study synthesized a new kind of pH-responsive active targeting glycodendrimer (ATGD) for doxorubicin delivery to cancerous cells. First, the glycodendrimer was synthesized based on the cultivation of chitosan dendrons on amine-functionalized, silica-grafted cellulose nanocrystals. Afterward, glycodendrimer was conjugated with folic acid to provide a folate receptor-targeting agent. The response surface method was employed to obtain the optimum conditions for the preparation of doxorubicin-loaded ATGD. The effect of doxorubicin/ATGD ratio, temperature, and pH on doxorubicin loading capacity was evaluated, and high loading capacity was achieved under optimized conditions. After determining doxorubicin release pattern at acidic and physiological pH, ATGD cytotoxicity was surveyed by MTT assay. Based on the results, the loading behavior of doxorubicin onto ATGD was in good agreement with monolayer-physisorption, and drug release was Fickian diffusion-controlled. ATGD could release the doxorubicin much more at acidic pH than physiological pH, corresponding to pH-responsive release behavior. Results of MTT assay confirmed the cytotoxicity of doxorubicin-loaded ATGD in cancer cells, while ATGD (without drug) was biocompatible with no tangible toxicity. These results suggested that ATGD has the potential for the treatment of cancer.

A review on biofilms and the currently available antibiofilm approaches: Matrix-destabilizing hydrolases and anti-bacterial peptides as promising candidates for the food industries.

Biofilms are communities of microorganisms that can be harmful and/or beneficial, depending on location and cell content. Since in most cases (such as the formation of biofilms in laboratory/medicinal equipment, water pipes, high humidity-placed structures, and the food packaging machinery) these bacterial and fungal communities are troublesome, researchers in various fields are trying to find a promising strategy to destroy or slow down their formation. In general, anti-biofilm strategies are divided into the plant-based and non-plant categories, with the latter including nanoparticles, bacteriophages, enzymes, surfactants, active peptides and free fatty acids. In most cases, using a single strategy will not be sufficient to eliminate biofilm, and consequently, two or more strategies will inevitably be used to deal with this unwanted phenomenon. According to the analysis of potential biofilm inhibition strategies, the best option for the food industry would be the use of hydrolase enzymes and peptides extracted from natural sources. This article represents a systematic review of the previous efforts made in these directions.

Sorafenib tosylate incorporation into mesoporous starch xerogel for in-situ micronization and oral bioavailability enhancement.

Poorly water-soluble drugs like sorafenib tosylate (SFB) can be made more soluble and orally bioavailable using a biocompatible hydrophilic matrix yields amorphous or microcrystalline drugs with high stability and low recrystallization risk. Mesoporous starch (MPS) due to its edibility, biodegradability, high surface area, and confined pores. In this study, MPS, either alone or in combination with polyvinylpyrrolidone (PVP), was employed for improving SFB oral bioavailability. To this aim, MPS was prepared in three steps: gelatinization, solvent exchange, and vacuum drying, after which it was used to incorporate SFB at various ratios using the immersion/solvent evaporation technique. Nitrogen adsorption/desorption analysis, Fourier transform infrared spectrometry (FTIR), field emission scanning electron microscopy (FE-SEM), powder X-ray diffraction (XRD) crystallography, and differential scanning calorimetry (DSC) were used to characterize SFB-loaded and drug-free samples, which confirmed the successful preparation of mesoporous structures with desirable uniform porosity, small pore size (about 5.3 nm), and specific surface area of about 24 m2/g. In-vitro dissolution testing revealed that the SFB dissolution rate increased substantially for the loaded MPS or MPS-PVP samples. Furthermore, when SFB was loaded in MPS-PVP, single-dose pharmacokinetics in rats confirmed an enhanced oral absorption kinetic. Therefore, impregnation of poorly soluble drugs such as SFB in the PVP-modified MPS excipient, which is constructed from a combination of mesoporous materials and a drug recrystallization inhibitor such as hydrophilic polymers, is proposed as a promising strategy for desirable enhancements in drug solubility, oral bioavailability, and efficacy.

In vitro DNA plasmid condensation and transfection through pH-responsive nanohydrogel.

Nanohydrogels (NHs) with the benefits of both nanomaterials and hydrogels unlock novel opportunities and applications in biomedicine. Nowadays, cationic NHs have attracted attention in the delivery of genetic materials into cells. Herein, by using reversible addition-fragmentation chain transfer method, an NH-based poly(hydroxyethyl methacrylate-co-N,N-dimethylaminoethyl methacrylate) and cross-linked by poly(ethylene glycol)diacrylate with pH responsiveness character was developed. Several techniques including nuclear magnetic resonance, Fourier-transform infrared spectroscopy, and gel permeation chromatography confirmed the success in the synthesis. The pH responsiveness of the developed NH was shown by transmission electron microscopy and dynamic light scattering technique. The average sizes of NHs in the normal (7.4) and acidic pH (5.5) were 180 and 390 nm, respectively. The ability of the developed NH to condense genetic materials was checked using gel retardation assay with different ratios of NH and pCMV6-IRES-AcGFP, as a plasmid encoding green fluorescence protein. Results of gel retardation assay showed a decreasing trend in plasmid electrophoretic mobility with the increase in the NH concentration. The NH/plasmid complexes were stopped completely at the ratio of 5 and the plasmid band vanished at the ratio of 10. The quantitative and qualitative results of the cell transfection experiment using different ratios of NH/plasmid showed the ability of NH to carry plasmid molecules into the cancerous cells. The best transfection efficiency was observed by nanohydrogel/plasmid weight ratio of 10, while other ratios including 2, 5 and 20 showed 0.8, 10 and 12% of transfection efficiency, respectively. All the assessed factors showed that NH has the potential to be considered as an efficient gene delivery vehicle.

Applications of Graphene and Graphene Oxide in Smart Drug/Gene Delivery: Is the World Still Flat?

Graphene, a wonder material, has made far-reaching developments in many different fields such as materials science, electronics, condensed physics, quantum physics, energy systems, etc. Since its discovery in 2004, extensive studies have been done for understanding its physical and chemical properties. Owing to its unique characteristics, it has rapidly became a potential candidate for nano-bio researchers to explore its usage in biomedical applications. In the last decade, remarkable efforts have been devoted to investigating the biomedical utilization of graphene and graphene-based materials, especially in smart drug and gene delivery as well as cancer therapy. Inspired by a great number of successful graphene-based materials integrations into the biomedical area, here we summarize the most recent developments made about graphene applications in biomedicine. In this paper, we review the up-to-date advances of graphene-based materials in drug delivery applications, specifically targeted drug/ gene delivery, delivery of antitumor drugs, controlled and stimuli-responsive drug release, photodynamic therapy applications and optical imaging and theranostics, as well as investigating the future trends and succeeding challenges in this topic to provide an outlook for future researches.

High yield gold nanoparticle-based DNA isolation method for human papillomaviruses genotypes from cervical cancer tissue samples.

Gold nanoparticles (AuNPs) are commonly used in biosensors of various kinds. However, its application to extract DNA from cancer tissues has not been extensively studied. The purification of DNA from cancer tissues is an important step in diagnostic and therapeutic development. Almost, all cervical cancer cases are associated with high-risk human papillomavirus (HR-HPV) infection. Accurate viral diagnosis has so far relied on the extraction of adequate amounts of DNA from formalin-fixed, paraffin-embedded (FFPE) tissue samples. Till now, no specific and sensitive DNA purification method has been introduced for the extraction of HR-HPV from FFPE tissue. Since the commercially available purification kits are not sensitive and specific enough for HR-HPV DNA targets, in this study, a DNA purification method was designed based on AuNPs to purify sufficient amounts of HR-HPV DNA from cervical cancer tissue samples. AuNPs were coated with a series of oligonucleotide probes to hybridize to specific DNA sequences of HR-HPV genotypes. Results showed that 733 out of 800 copies of type-specific HPV DNA were recovered with complete specificity, compared to 36 copies with a standard commercial kit (Qiagen FFPE). The high yield of DNA (91.6%) is the main advantage of the AuNPs-probe purification method.

Insulin fibrillation: toward strategies for attenuating the process.

Dark days for diabetic patients were transformed into an era of hope when the therapeutic usage of insulin was discovered. However, those initial glory days changed to being somewhat gloomy, when it was discovered that insulin easily undergoes undesirable, fast, and non-reversible aggregation and fibrillation. After more than half a century of intensive attempts to limit the rate of the insulin aggregation and fibrillation, there is no clear-cut strategy for eliminating these processes once and for all. A plethora of studies focused on using various organic compounds to combat the process, whereas other researchers believe that the process can be inhibited (or altered) by well-designed nanoparticles. In an attempt to inhibit insulin aggregation, some other approaches, such as protein/peptide inhibitors, have been considered for therapeutic purposes. Beyond biological processes and interactions between biological molecules, there are also strong physicochemical laws. Therefore, the goal of this article is to provide an overview of chemical, physical, and biological studies dedicated to the analysis of approaches that attenuate and inhibit insulin aggregation and fibrillation. After a detailed characterization of the insulin fibrillation process, this review focuses on various aspects related to the inhibition and modulation of insulin fibrillation using nanoparticles, proteins/peptides, and cyclic and non-cyclic compounds. Hopefully, these findings will pave the way for scientists in various fields to increase the stability of pharmaceutical proteins and peptides.

Synthesis of novel reducing agent for formation of metronidazole-capped silver nanoparticle and evaluating antibacterial efficiency in gram-positive and gram-negative bacteria.

In this study, a new type of silver nanoparticles capped with metronidazolium based ionic liquid is synthesized. By this aim, metronidazole is altered to ionic-liquid type structure with citrate counter ion as reducing agent. The produced reducing agent was characterized using 1HNMR and 13CNMR and FT-IR. The capability of metronidazolium-based reducing agent in formation and capping silver nanoparticles was examined in a chemical reaction. More specifically, synthesized silver nanoparticles were synthesized and capped with metronidazolium-citrate based ionic liquid, while the formation of particles in 48 h was monitored by UV-Vis spectroscopy. Fourier transform infrared spectroscopy showed the presence of capping agents around silver nanoparticles. The amount of metronidazolium and citrate as capping agents was determined by thermal gravimetric analysis. The prepared crystalline structure of silver nanoparticles was proved by X-ray diffraction spectroscopy. PSA analysis and TEM was performed to determine the size of particles. The synthesized silver nanoparticle has the potential to be used as an antibacterial agent in preparation of wound dressing with extra capability and efficacy in aerobic and anaerobic bacterium. In this regard, the antibacterial efficacy of discs from different concentration of silver nanoparticles in calcium alginate medium were evaluated in Gram-negative and Gram-positive bacterium.

Stimulus-Responsive Sequential Release Systems for Drug and Gene Delivery.

In recent years, a range of studies have been conducted with the aim to design and characterize delivery systems that are able to release multiple therapeutic agents in controlled and programmed temporal sequences, or with spatial resolution inside the body. This sequential release occurs in response to different stimuli, including changes in pH, redox potential, enzyme activity, temperature gradients, light irradiation, and by applying external magnetic and electrical fields. Sequential release (SR)-based delivery systems, are often based on a range of different micro- or nanocarriers and may offer a silver bullet in the battle against various diseases, such as cancer. Their distinctive characteristic is the ability to release one or more drugs (or release drugs along with genes) in a controlled sequence at different times or at different sites. This approach can lengthen gene expression periods, reduce the side effects of drugs, enhance the efficacy of drugs, and induce an anti-proliferative effect on cancer cells due to the synergistic effects of genes and drugs. The key objective of this review is to summarize recent progress in SR-based drug/gene delivery systems for cancer and other diseases.

Recent Advances in Designing 5-Fluorouracil Delivery Systems: A Stepping Stone in the Safe Treatment of Colorectal Cancer.

5-Fluorouracil (5-FU) has become one of the most widely employed antimetabolite chemotherapeutic agents in recent decades. It is considered a first line antineoplastic agent for the treatment of colorectal cancer. Unfortunately, chemotherapy with 5-FU has several limitations, including its short half-life, high cytotoxicity and low bioavailability. In order to overcome the drawbacks of 5-FU and enhance its therapeutic efficiency, many scientific groups have focused on designing a new delivery system to successfully deliver 5-FU to tumor sites. We provide a comprehensive review on different strategies to design effective delivery systems, including nanoformulations, drug-conjugate formulations and other strategies for the delivery of 5-FU to colorectal cancer. Furthermore, co-delivery of 5-FU with other therapeutics is discussed. This review critically highlights the recent innovations in and literature on various types of carrier system for 5-FU.

Core-Shell Imidazoline-Functionalized Mesoporous Silica Superparamagnetic Hybrid Nanoparticles as a Potential Theranostic Agent for Controlled Delivery of Platinum(II) Compound.

INTRODUCTION: As widely used chemotherapeutic agents, platinum compounds have several therapeutic challenges, such as drug resistance and adverse effects. Theranostic systems, macromolecular or colloidal therapeutics with companion diagnostics, not only address controlled drug delivery but also enable real-time monitoring of tumor sites. METHODS: Synthesis of magnetic mesoporous silica nanoparticles (MMSNs) was performed for dual magnetic resonance imaging and drug delivery. MMSN surfaces were modified by imidazoline groups (MMSN-Imi) for cisplatin (Cis-Pt) conjugation via free N-termini to achieve well-controlled drug-release kinetics. Cis-Pt adsorption isotherms and drug-release profile at pH 5 and 7.4 were investigated using inductively coupled plasma atomic emission spectroscopy. RESULTS: MMSN-Imi showed a specific surface area of 517.6 m2 g-1, mean pore diameter of 3.26 nm, and saturated magnetization of 53.63 emu/g. A relatively high r2/r1 relaxivity value was obtained for MMSN-Imi. The nanoparticles provided high Cis-Pt loading with acceptable loading capacity (~30% w:w). Sustained release of Cis-Pt under acidic conditions led to specific inhibitory effects on the growth of human epithelial ovarian carcinoma cells, determined using MTT assays. Dual acridine orange-propidium iodide staining was investigated, confirming induction of apoptosis and necrotic cell death. CONCLUSION: MMSN-Imi exhibited potential for applications in cancer chemotherapy and combined imaging.

Effects of different quantities of antibody conjugated with magnetic nanoparticles on cell separation efficiency.

Antibody-conjugated magnetic nanoparticles (Ab-MNPs) have received considerable attention in bioseparation and clinical diagnostics assays due to their unique ability to detect and isolate a variety of biomolecules and cells. Because antibodies can be expensive, a key challenge for bioconjugation is to determine the optimal amount of antibodies with reasonable antigen-capturing activity. We designed an approach to determine the minimum amounts of antibodies for efficient coating. Different quantities of Herceptin (anti-human epidermal growth factor receptor 2: HER2) antibody were applied and immobilized on the surface of MNPs. Antibody binding was then checked by using an anti-human antibody conjugated with fluorochrome and flow cytometry. When the ratio of MNPs to antibodies increased from 0.79 to 795.45, mean fluorescence intensity (MFI) of conjugated MNPs decreased markedly from 185.56 to 20.07, indicating lower surface antibody coverage. We then investigated the relation between antibody content and isolation efficiency. Three Ab-MNP samples with different MFI were used to isolate SK-BR-3, a HER2-positive breast cancer cell line, from mixtures of whole blood or mononuclear cells. After isolation in a magnetic field, separation efficiency was evaluated by fluorescence microscopy and flow cytometry-based techniques. Our results collectively showed that the amount of anti-HER2 antibodies for conjugation with MNPs could be decreased by as much as one-fifteenth without compromising isolation efficiency, which in turn can reduce the cost of immunoassay biosensors.

Temperature and pH-responsive nano-hydrogel drug delivery system based on lysine-modified poly (vinylcaprolactam).

BACKGROUND: Smart materials capable of responding to external stimuli are noteworthy candidates in designing drug delivery systems. In many of the recent research, temperature and pH have been recognized as the main stimulating factors in designing systems for anti-cancer drugs delivery systems. PURPOSE: In this study, thermo and pH-responsive character of a nano-carrier drug delivery platform based on lysine modified poly (vinylcaprolactam) hydrogel conjugated with doxorubicin was assessed. METHODS: Poly (vinylcaprolactam) cross-linked with poly (ethyleneglycol) diacrylate was prepared via RAFT polymerization, and the prepared structure was linked with lysine through ring-opening. The anti-cancer drug doxorubicin, was linked to lysine moiety of the prepared structure via Schiff-base reaction. The prepared platform was characterized by 1HNMR and FT-IR, while molecular weight characterization was performed by size exclusion chromatography. The temperature-responsive activity was evaluated using differential scanning calorimetry and dynamic light scattering. In vitro release pattern in simulated physiologic pH at 37°C was compared with acidic pH attributed to tumor site and elevated temperature. The anticancer efficiency of the drug-conjugated structure was evaluated in breast cancer cell line MCF-7 in 24 and 48 h, and cell uptake assay was performed on the same cell line. CONCLUSION: According to the results, well-structure defined smart pH and temperature responsive nano-hydrogel was prepared. The enhanced release rates are observed at acidic pH and elevated temperature. We have concluded that the doxorubicin-conjugated nanoparticle results in higher cellular uptakes and more cytotoxicity.

Smart pH responsive drug delivery system based on poly(HEMA-co-DMAEMA) nanohydrogel.

The advent of smart nanohydrogel has revealed new opportunities for scientists to develop the most efficient anti-cancer vehicles with safe and biocompatible profile. In this experiment, using reversible addition-fragmentation chain transfer polymerization method as a novel, safe and smart pH responsive formulation of poly (hydroxyethyl methacrylate-co-N,N-dimethylaminoethyl methacrylate) and poly (ethylene glycol)-diacrylate as cross-linker were synthesized. The synthesized structure was confirmed by Fourier-transform infrared spectroscopy and proton nuclear magnetic resonance methods. The pH responsive behavior of the synthesized particles was checked by size measurement in two different pH values (5.5 and 7.4) by dynamic light scattering and transmission electron microscopy. The prepared structure had nanometer sizes of 180 in medium with pH of 7.4, when it encountered acidic medium (e.g. pH 5.5), the particles swelled to about 400 nm. The efficiency of the prepared pH responsive nanohydrogels was tested as a drug delivery system. An anti-cancer drug, doxorubicin successfully interacted with this material. The release profiles of nanoparticles carrying drug molecules were checked in two different simulated pH of healthy organs (7.4) and tumor site (5.5). Despite lower release in pH of 7.4 (∼20%), an increased drug release of 80% was obtained in pH of 5.5. The in vitro toxicity assay, apoptosis evaluation and uptake experiments were performed on breast cancer cell line (MCF-7), which showed a time dependency cellular entrance, an enhanced cytotoxicity and apoptosis induction by the doxorubicin loaded nanoparticles. Hemolysis assays confirmed the safety and hemocompatibility of the developed nanohydrogel. The suitable size (<200 nm), pH responsive behavior, anti-proliferative activity and apoptosis induction in cancer cells and hemocompatibility were the noticeable features of the developed doxorubicin adsorbed nanoparticle, which introduced this formulation as an ideal vehicle in anti-cancer drug delivery.

Bacterial components as naturally inspired nano-carriers for drug/gene delivery and immunization: Set the bugs to work?

Drug delivery is a rapidly growing area of research motivated by the nanotechnology revolution, the ideal of personalized medicine, and the desire to reduce the side effects of toxic anti-cancer drugs. Amongst a bewildering array of different nanostructures and nanocarriers, those examples that are fundamentally bio-inspired and derived from natural sources are particularly preferred. Delivery of vaccines is also an active area of research in this field. Bacterial cells and their components that have been used for drug delivery, include the crystalline cell-surface layer known as "S-layer", bacterial ghosts, bacterial outer membrane vesicles, and bacterial products or derivatives (e.g. spores, polymers, and magnetic nanoparticles). Considering the origin of these components from potentially pathogenic microorganisms, it is not surprising that they have been applied for vaccines and immunization. The present review critically summarizes their applications focusing on their advantages for delivery of drugs, genes, and vaccines.