A novel design of nanoscopic volume transmitter and receiver for drug delivery system using a PANDA ring resonator is proposed. By controlling some suitable parameters, the optical vortices (gradient optical fields/wells) can be generated and used to form the trapping tools in the same way as the optical tweezers. By using the intense optical vortices generated within the PANDA ring resonator, the nanoscopic volumes (drug) can be trapped and moved (transport) dynamically within the wavelength router or network. In principle, the trapping force is formed by the combination between the gradient field and scattering photons, which is reviewed. The advantage of the proposed system is that a transmitter and receiver can be formed within the same system (device), which is called a transceiver, which is available for nanoscopic volume (drug volume) trapping and transportation (delivery).
Matched MeSH terms: Drug Delivery Systems/methods*
Mebeverine HCl is a water soluble drug commonly used to treat irritable bowel syndrome by acting directly on the smooth muscles of the colon. This work was aimed at the formulation and in vitro evaluation of a colon-targeted drug delivery system containing mebeverine HCl. Matrix tablets were prepared using ethyl cellulose (EC), Eudragit RL 100 either solely or in combination by wet granulation technique. Dissolution was carried out in 0.1 N HCl for 2?h followed by pH 6.8 phosphate buffer for eight hours. Uncoated forms released more than 5% drug in 0.1 N HCl therefore, Eudragit L100 was used as a coat. The results indicated very slow release profile. As a result, single retardant was used to prepare the matrix and coated by Eudragit L 100. The matrix containing 7% Eudragit RL 100 and 6% of binder was subjected to further studies to assess the effect of different coats (Eudragit L 100-55 and cellulose acetate phthalate) and different binders (pectin and sodium alginate) on the release profile. Eudragit L 100 and pectin were the best coating agent and binder, respectively. The final formula was stable and it can be concluded that the prepared system has the potential to deliver mebeverine HCl in vivo to the colon.
Matched MeSH terms: Drug Delivery Systems/methods*
This study explored the potential of soluble dietary fiber (SDF) from agrowastes, okara (soybean solid waste), oil palm trunk (OPT), and oil palm frond (OPF) obtained via alkali treatment, in the nanoencapsulation of Lactobacillus acidophilus . SDF solutions were amended with 8% poly(vinyl alcohol) to produce nanofibers using electrospinning technology. The spinning solution made from okara had a higher pH value at 5.39 ± 0.01 and a higher viscosity at 578.00 ± 11.02 mPa·s (P < 0.05), which resulted in finer fibers. FTIR spectra of nanofibers showed the presence of hemicellulose material in the SDF. Thermal behavior of nanofibers suggested possible thermal protection of probiotics in heat-processed foods. L. acidophilus was incorporated into the spinning solution to produce nanofiber-encapsulated probiotic, measuring 229-703 nm, visible under fluorescence microscopy. Viability studies showed good bacterial survivability of 78.6-90% under electrospinning conditions and retained viability at refrigeration temperature during the 21 day storage study.
Matched MeSH terms: Drug Delivery Systems/instrumentation*; Drug Delivery Systems/methods
Design of oral fast-release solid dispersion of poorly water-soluble drugs has been a great challenge over past decades on issues of drug recrystallization, drug polymorphism, formulation limited to low drug-to-carrier ratio and drug particle aggregation in matrix. The complexity in solid dispersion design is envisaged to be resolvable by the use of nanoparticulate system as solid dosage form. This manuscript reviews several patented processing approaches of nanoparticulate solid dispersion that have been reported recently. Through drug nanoencapsulation, a higher content of drug may be delivered with less aggregation via placing the same drug mass in a greater number of tinier carriers. Nanoencapsulation, by its own process of formation, brings about submicron particles. Keeping drug in these nanoparticles, a remarkable rise in specific surface area of drug is realized for dissolution. The augmentation of drug dissolution can be sufficiently high to the extent that the influences of polymorphism and crystallization phenomenon on drug dissolution in a solid dispersion may be negligible.
In endoscopic neurosurgery problems with haemostasis due to poor access exist. We have developed a system which allows the delivery of a variety of haemostatic agents in a more efficacious manner. The system has been used successfully in endoscopic skull base surgery and endoscopic surgery within the parenchyma of the brain using tube systems.
Matched MeSH terms: Drug Delivery Systems/instrumentation*; Drug Delivery Systems/methods
By using a pair of tweezers to generate the intense optical vortices within the PANDA ring resonator, the required molecules (drug volumes) can be trapped and moved dynamically within the molecular bus networks, in which the required diagnosis or drug delivery targets can be performed within the network. The advantage of the proposed system is that the proposed diagnostic method can perform within the tiny system (thin film device or circuit), which can be available for a human embedded device for diagnostic use. The channel spacing of the trapped volumes (molecules) within the bus molecular networks can be provided.
Matched MeSH terms: Drug Delivery Systems/instrumentation; Drug Delivery Systems/methods*
Use of alginate graft copolymers in oral drug delivery reduces dosage form manufacture complexity with reference to mixing or coating processes. It is deemed to give constant or approximately steady weight ratio of alginate to covalently attached co-excipient in copolymers, thereby leading to controllable matrix processing and drug release. This review describes various grafting approaches and their outcome on oral drug release behaviour of alginate graft copolymeric matrices. It examines drug release modulation mechanism of alginate graft copolymers against that of co-excipients in non-grafted formulations.
The phase behaviour of a system composed of amino acid-based surfactant (sodium N-lauroylsarcosinate hydrate), 1-decanol and deionised water was investigated for vesicle formation. Changing the molar ratio of the amphiphiles, two important aggregate structures were observed in the aqueous corner of the phase diagram. Two different sizes of microemulsions were found at two amphiphile-water boundaries. A stable single vesicle lobe was found for 1∶2 molar ratios in 92 wt% water with vesicles approximately 100 nm in size and with high zeta potential value. Structural variation arises due to the reduction of electrostatic repulsions among the ionic headgroups of the surfactants and the hydration forces due to adsorbed water onto monolayer's. The balance of these two forces determines the aggregate structures. Analysis was followed by the molecular geometrical structure. These findings may have implications for the development of drug delivery systems for cancer treatments, as well as cosmetic and food formulations.
The aim of this study was to optimize the different process parameters including pressure, temperature, and polymer concentration, to produce fine small spherical particles with a narrow particle size distribution using a supercritical antisolvent method for drug encapsulation. The interaction between different process parameters was also investigated.
Matched MeSH terms: Drug Delivery Systems/methods*
A novel nanomicro syringe system was proposed for drug storage and delivery using a PANDA ring resonator and atomic buffer. A PANDA ring is a modified optical add/drop filter, named after the well known Chinese bear. In principle, the molecule/drug is trapped by the force generated by different combinations of gradient fields and scattering photons within the PANDA ring. A nanomicro needle system can be formed by optical vortices in the liquid core waveguide which can be embedded on a chip, and can be used for long-term treatment. By using intense optical vortices, the required genes/molecules can be trapped and transported dynamically to the intended destinations via the nanomicro syringe, which is available for drug delivery to target tissues, in particular tumors. The advantage of the proposed system is that by confining the treatment area, the effect can be decreased. The use of different optical vortices for therapeutic efficiency is also discussed.
Matched MeSH terms: Drug Delivery Systems/instrumentation*; Drug Delivery Systems/methods
An ellagic acid (EA)-zinc layered hydroxide (ZLH) nanohybrid (EAN) was synthesized under a nonaqueous environment using EA and zinc oxide (ZnO) as the precursors. Powder X-ray diffraction showed that the basal spacing of the nanohybrid was 10.4 Å, resulting in the spatial orientation of EA molecules between the interlayers of 22.5° from z-axis with two negative charges at 8,8' position of the molecules pointed toward the ZLH interlayers. FTIR study showed that the intercalated EA spectral feature is generally similar to that of EA, but with bands slightly shifted. This indicates that some chemical bonding of EA presence between the nanohybrid interlayers was slightly changed, due to the formation of host-guest interaction. The nanohybrid is of mesopores type with 58.8% drug loading and enhanced thermal stability. The release of the drug active, EA from the nanohybrid was found to be sustained and therefore has good potential to be used as a drug controlled-release formulation. In vitro bioassay study showed that the EAN has a mild effect on the hepatocytes cells, similar to its counterpart, free EA.
Matched MeSH terms: Drug Delivery Systems/methods*
In recent years, several paramyxoviruses have emerged to infect humans, including previously unidentified zoonoses. Hendra and Nipah viruses (henipaviruses within this family) were first identified in the 1990s in Australia, Malaysia and Singapore, causing epidemics with high mortality and morbidity rates in affected animals and humans. Other paramyxoviruses, such as Menangle virus, Tioman virus, human metapneumovirus and avian paramyxovirus 1, which cause less morbidity in humans, have also been recently identified. Although the Paramyxoviridae family of viruses has been previously recognised as biomedically and veterinarily important, the recent emergence of these paramyxoviruses has focused our attention on this family. Antiviral drugs can be designed to target specific important determinants of the viral life cycle. Therefore, identifying and understanding the mechanistic underpinnings of viral entry, replication, assembly and budding will be critical in the development of antiviral therapeutic agents. This review focuses on the molecular mechanisms discovered and the antiviral strategies pursued in recent years for emerging paramyxoviruses, with particular emphasis on viral entry and exit mechanisms.
Recently, research and development in the field of drug delivery systems (DDS) facilitating site-specific therapy has reached significant progression. DDS based on polymer micelles, coated micro- and nanoparticles, and various prodrug systems including water-soluble polymer have been prepared and extensively studied as novel drugs designed for cancer chemotherapy and brain delivery. Since polymers are going to be used in human, this study has the interest of testing two types of polymer, polyimides (PI) and polyphenylenevinylene (PPV) on neuronal cells. The objective of this study was to determine the possible neurotoxicity and potential neuroprotective effects of PI and PPV towards SH-SY5Y neuronal cells challenged by hydrogen peroxide (1120) as an oxidant. Cells were pretreated with either PI or PPV for 1 hour followed by incubation for 24 hour with 100 ,uM of 11201. MTS • assay was used to assess cell viability. Results show that PI and PPV are not harmful within the concentration up to 10 pM and 100 pM, respectively. However, PI and PPV do not protect neuronal cells against toxicity induced by H2O, or further up the cell death.
The review focuses on the application of supercritical fluids as antisolvents in the pharmaceutical field and demonstrates the supercritical antisolvent method in the use of drug encapsulation. The main factors for choosing the solvent and biodegradable polymer to produce fine particles to ensure effective drug delivery are emphasized and the effect of polymer structure on drug encapsulation is illustrated. The review also demonstrates the drug release mechanism and polymeric controlled release system, and discusses the effects of the various conditions in the process, such as pressure, temperature, concentration, chemical compositions (organic solvents, drug, and biodegradable polymer), nozzle geometry, CO(2) flow rate, and the liquid phase flow rate on particle size and its distribution.
Matched MeSH terms: Drug Delivery Systems/methods*
Synthetic membranes are composed of thin sheets of polymeric macromolecules that can control the passage of components through them. Generally, synthetic membranes used in drug diffusion studies have one of two functions: skin simulation or quality control. Synthetic membranes for skin simulation, such as the silicone-based membranes polydimethylsiloxane and Carbosil, are generally hydrophobic and rate limiting, imitating the stratum corneum. In contrast, synthetic membranes for quality control, such as cellulose esters and polysulfone, are required to act as a support rather than a barrier. These synthetic membranes also often contain pores; hence, they are called porous membranes. The significance of Franz diffusion studies and synthetic membranes in quality control studies involves an understanding of the fundamentals of synthetic membranes. This article provides a general overview of synthetic membranes, including a brief background of the history and the common applications of synthetic membranes. This review then explores the types of synthetic membranes, the transport mechanisms across them, and their relevance in choosing a synthetic membrane in Franz diffusion cell studies for formulation assessment purposes.
Optical vorticesare generated and controlled to form trapping tools in the same way as optical tweezers. By using the intense optical vortices generated within the PANDA ring resonator, the required atoms/molecules can be trapped and moved (transported) dynamically within the wavelength router or network. The advantage of the proposed system is that a transmitter and receiver can be formed within the same system, which is available for atoms/molecules storage and transportation based on methods that have been proposed to deliver drugs into cells for specific diagnosis.
The aim of the present investigation was to formulate thermally sintered floating tablets of propranolol HCl, and to study the effect of sintering conditions on drug release, as well as their in vitro buoyancy properties. A hydrophilic polymer, polyethylene oxide, was selected as a sintered polymer to retard the drug release. The formulations were prepared by a direct compression method and were evaluated by in vitro dissolution studies. The results showed that sintering temperature and time of exposure greatly influenced the buoyancy, as well as the dissolution properties. As the sintering temperature and time of exposure increased, floating lag time was found to be decreased, total floating time was increased and drug release was retarded. An optimized sintered formulation (sintering temperature 50 degrees C and time of exposure 4 h) was selected, based on their drug retarding properties. The optimized formulation was characterized with FTIR and DSC studies and no interaction was found between the drug and the polymer used.
Cell-internalizing peptides (CIPs) can be used to mediate specific delivery of nanoparticles across cellular membrane. The objective of this study was to develop a display technique using hepatitis B virus (HBV) capsid-binding peptide as a "nanoglue" to present CIPs on HBV nanoparticles for cell-targeting delivery. A CIP was selected from a phage display library and cross-linked specifically at the tips of the spikes of the HBV capsid nanoparticle via the "nanoglue" by using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) and N-hydroxysulfosuccinimide (sulfo-NHS). Fluorescent oligonucleotides packaged in the nanoparticles and the fluorescein molecules conjugated on the nanoparticles were delivered to cells by using this display technique. This study demonstrated a proof of principle for cell-targeting delivery via "nanoglue" bioconjugation.
Matched MeSH terms: Drug Delivery Systems/methods*
The aims of this research were to develop a novel bilayer hydrocolloid film based on alginate and to investigate its potential as slow-release wound healing vehicle. The bilayer is composed of an upper layer impregnated with model drug (ibuprofen) and a drug-free lower layer, which acted as a rate-controlling membrane. The thickness uniformity, solvent loss, moisture vapour transmission rate (MVTR), hydration rate, morphology, rheology, mechanical properties, in vitro drug release and in vivo wound healing profiles were investigated. A smooth bilayer film with two homogenous distinct layers was produced. The characterisation results showed that bilayer has superior mechanical and rheological properties than the single layer films. The bilayers also showed low MVTR, slower hydration rate and lower drug flux in vitro compared to single layer inferring that bilayer may be useful for treating low suppurating wounds and suitable for slow release application on wound surfaces. The bilayers also provided a significant higher healing rate in vivo, with well-formed epidermis with faster granulation tissue formation when compared to the controls. In conclusions, a novel alginate-based bilayer hydrocolloid film was developed and results suggested that they can be exploited as slow-release wound dressings.