pH-sensitive and targeted PLGA-based drug delivery to colorectal cancer

Investigation on targeted PLGA based drug delivery system for the therapy of colorectal cancer. The results from in-vitro cell experiments indicated that prepared systems have potent cytotoxicity and high affinity to HT-29 cancer cells. Results were published on Biomedical Engineering and Informatics and ICONN conference proceeding.

Tailored hollow mesoporous silica nanoplatforms with biological labels for colon targeted drug deliver systems

Hollow mesoporous silica nanoparticles (HMSNs) were synthesized via a new strategy. HMSNs have a high drug loading, controlled release behaviour, and specifically targeting when bioconjugated with Epidermal Growth Factor. The promising in vitro cell tests have revealed the great potential of the HMSNs to be used for cancer therapy.

Manufacturing techniques and surface engineering of polymer based nanoparticles for targeted drug delivery to cancer

The evolution of polymer based nanoparticles as a drug delivery carrier via pharmaceutical nano/microencapsulation has greatly promoted the development of nano- and micro-medicine in the past few decades. Poly(lactide-co-glycolide) (PLGA) and chitosan, which are biodegradable and biocompatible polymers, have been approved by both the Food & Drug Administration (FDA) and European Medicine Agency (EMA), making them ideal biomaterials that can be advanced from laboratory development to clinical oral and parental administrations. PLGA and chitosan encapsulated nanoparticles (NPs) have successfully been developed as new oral drug delivery systems with demonstrated high efficacy. This review aims to provide a comprehensive overview of the fabrication of PLGA and chitosan particulate systems using nano/microencapsulation methods, the current progress and the future outlooks of the nanoparticulate drug delivery systems. Especially, we focus on the formulations and nano/micro-encapsulation techniques using top-down techniques. It also addresses how the different phases including the organic and aqueous ones in the emulsion system interact with each other and subsequently influence the properties of the drug delivery system. Besides, surface modification strategies which can effectively engineer intrinsic physicochemical properties are summarised. Finally, future perspectives and potential directions of PLGA and chitosan nano/microencapsulated drug systems are outlined.

Tailored mesoporous silica nanoparticles for controlled drug delivery: platform fabrication, targeted delivery, and computational design and analysis

Mesoporous silica nanoparticles (MSNs) are exceptionally promising drug carriers for controlled drug delivery systems because their morphology, pore structure, pore volume and pore size can be well tailored to obtain certain drug release profiles. Moreover, they possess the ability to specifically transport and deliver anti-cancer drugs when targeting molecules are properly grafted onto their surface. MSNs based drug delivery systems have the potential to revolutionize cancer therapy. This review provides a comprehensive overview of the fabrication, modification of MSNs and their applications in tumour-targeted delivery. In addition, the characterization and analysis of MSNs with computer aided strategies were described. The existing issues and future prospective concerning the applications of MSNs as drug carriers for controlled drug delivery systems were discussed.

Multifunctional and multitargeted nanoparticles for drug delivery to overcome barriers of drug resistance in human cancers

The recurrence and metastatic spread of cancer are major drawbacks in cancer treatment. Although chemotherapy is one of the most effective methods for the treatment of metastatic cancers, it is nonspecific and causes significant toxic damage. The development of drug resistance to chemotherapeutic agents through various mechanisms also limits their therapeutic potential. However, as we discuss here, the use of nanodelivery systems that are a combination of diagnostics and therapeutics (theranostics) is as relatively novel concept in the treatment of cancer. Such systems are likely to improve the therapeutic benefits of encapsulated drugs and can transit to the desired site, maintaining their pharmaceutical properties. The specific targeting of malignant cells using multifunctional nanoparticles exploits theranostics as an improved agent for delivering anticancer drugs and as a new solution for overriding drug resistance.

Intracellular drug delivery by sulfatide-mediated liposomes to gliomas

We described here a liposomal carrier system in which the targeting ligand was sulfatide, a glycosphingolipid known to bind several extracellular matrix (ECM) glycoproteins whose expression was highly up-regulated in many tumors. In vitro experiments with human glioma cell lines demonstrated that robust intracellular uptake of the liposomes depended specifically on the presence of sulfatide as the key liposomal component. Significant amount of the liposomes remained largely intact in the cytoplasm for hours following their internalization. When anticancer drug doxorubicin (DOX) was encapsulated in such liposomes, most of the drug was preferably delivered into the cell nuclei to exert its cytotoxicity. Use of this drug delivery system to deliver DOX for treatment of tumor-bearing nude mice displayed much improved therapeutic effects over the free drug or the drug carried by polyethylene glycol (PEG)-grafted liposomes. Our results demonstrate a close link between effective intracellular uptake of the drug delivery system and its therapeutic outcome. Moreover, the sulfatide-containing liposomes (SCL) may represent an interesting ligand-targeted drug carrier for a wide spectrum of cancers in which sulfatide-binding ECM glycoproteins are expressed.

A potential application of a piezoelectric atomiser for ophthalmic drug delivery

A liquid atomiser composed of a piezoelectric transducer and a metal plate with numerous micro-apertures is studied to identify the most influential factors on its atomising performance. The Taguchi method is employed in the experiment design and analysis of the study on how each factor acts in the atomising process. An optimal condition is determined for producing a stream of droplets. The study shows that the droplet size and the spraying velocity are suitable for ophthalmic drug delivery application, with an even distribution of the drug over most of the eyeball surface area due to the controllable cross-sectional area of the droplet stream. This greatly improves the treatment effectiveness and efficiency of eye therapy. Finally, a structure of the ophthalmic drug delivery system is proposed.

Boron nitride nanotubes : a novel vector for targeted magnetic drug delivery

Whereas several biomedical applications of carbon nanotubes have been proposed, the use of boron nitride nanotubes (BNNTs) in this field has been largely unexplored despite their unique and potentially useful properties. Our group has recently initiated an experimental program aimed at the exploration of the interactions between BNNTs and living cells. In the present paper, we report on the magnetic properties of BNNTs containing Fe catalysts which confirm the feasibility for their use as nanovectors for targeted drug delivery. The magnetisation curves of BNNTs characterised by the present study are typical of superparamagnetic materials with important parameters, including magnetic permeability and magnetic momentum, derived by employing Langevin theory. In-vitro tests have demonstrated the feasibility for influencing the uptake of BNNTs by living cells by exposure to an external magnetic source. A finite element method analysis devised to predict this effect produced predictive data with close agreement with the experimental observations.

Recent advances in nanoneurology for drug delivery to the brain

The drug development for neurodegenerative disorders are the major challenge to the science in 21st century. Many FDA approved drugs currently available in the market have limitations in crossing the blood brain barrier (BBB) owing to its complicated vasculature posed by the presence of specialized cells. Nanotechnology is an emerging interdisciplinary area, which have many applications including drug delivery. Nanocarrier drug delivery involves targeting drugs enclosed in a particular polymer and/or amphiphilic lipids. Controlled release, nanoplatform availability for combinatorial therapy and tissue specific targeting by using advanced technologies such as molecular Trojan horse (MTH) technology are the promises of nanotechnology. Different problems are associated with drug delivery
across the BBB. Some are mostly related to the structure of brain microvasculature system while the others are related to the nanomaterial
structure. Different strategies, such as using polymeric/solid lipid nanoparticles and surface modification of nanomaterial with surfactants
like polysorbates have been conducted to solve these limitations. Also, nanodrug formulations with double coatings have been designed for oral delivery of drugs to overcome reticulo-endothelial system and to improve their BBB permeability. It seems that the best choice of strategy and material could be achieved with regard to the physical and chemical structure of the drugs. The present review discusses the potential applications of nanotechnology for drug delivery across the BBB.

Promises of nanotechnology for drug delivery to brain in neurodegenerative diseases

Brain is a delicate organ, isolated from general circulation and characterized by the presence of relatively impermeable endothelial cells with tight junctions, enzymatic activity and the presence of active efflux transporter mechanisms. These formidable obstacles often block drug delivery to the brain across the blood-brain barrier (BBB). Although several promising molecules have the potential in the in vitro settings but lack of in vivo response is probably because the molecule cannot reach the brain in a sufficient concentration. Drug delivery across the BBB is a major limitation in the treatment of central nervous system (CNS) disorders and CNS infections. This review deals with the role of nanobiotechnology in CNS drug delivery, in which three categories of carbon nanotubes, nanowires and nanoparticles (NPs) are explained. The small size of the NPs makes them an ideal choice to penetrate the BBB. Several mechanisms are involved in this process and various strategies are used. There are some concerns about the safety of NP entry in the brain that need to be resolved before human use. Although there is no approved nanotechnology-based CNS drug available the future for such neuro-nanobiotechnology based delivery system developments is promising.

Design and construction of a micropump for drug delivery applications

This paper presents design, construction, and evaluation of a micropump for drug delivery applications. The proposed micropump consists of three components: fluidics, electronics, and software. The fluidics component includes a silicone elastic diaphragm, a microservo, housing and two check valves. The diaphragm is modeled and simulated to establish its geometrical specifications. The housing is built using a rapid prototype machine. The electronics component consists of a microcontroller, a microswitch array, a simple display and a power unit. The software component is written in C and receives inputs from user, controls the microservo speed and displays the programmed speed. A number of experiments are conducted to evaluate the performance and capabilities of the micropump. The experiments focus on measurement of flow rate, dosage and duration of operation. A discussion of the performance and capabilities of the developed micropump is also given.

Formulation optimization for high drug loading colonic drug delivery carrier

High drug loading (DL) carrier is an effective way to cure the cancerous cells. High drug loading is also one of the key issues in the drug delivery research, especially the colonic drug delivery system by oral administration. The times of drug intake could be remarkably reduced if high drug loading carriers are administered. At the same time, the related formulation materials could be effectively utilized. One major obstacle with the preparation of this system is the difficulty to encapsulate the hydrophilic drug into hydrophobic encapsulation polymer. A design of high drug loading delivery system with biodegradable, biocompatible materials and optimization of the fabrication process is a potential solution to solve the problem. So in this research, 5-Fluorouracil (5-FU) loaded Poly (lactide-co-glycolide) (PLGA) nanoparticles were prepared by double emulsion and solvent evaporation method. Several fabrication parameters including theoretical drug loading, volume ratio of outer water phase to the first emulsion, pH value of outer aqueous phase and emulsifier PVA concentration were optimized to get a high drug loading nanoparticles. The result shows that with the increase of theoretical drug loading, the actual drug loading increased gradually. When adjusted the pH value of outer aqueous phase to the isoelectric point (8.02) of 5-Fluorouracil, the drug loading exhibited a higher one compared to other pH value solution. Relative higher volume ratio of outer water phase to the first emulsion was also beneficial for the enhancement of drug loading. But the nanoparticles size increased simultaneously due to the lower shearing force. When increased the PVA concentration, the drug loading showed an increase first and following a drop.