Displaying publications 1 - 20 of 516 in total

Abstract:
Sort:
  1. Tariq AR
    Med J Malaysia, 1993 Sep;48(3):253-5.
    PMID: 8183134
    Matched MeSH terms: Drug Delivery Systems*
  2. Wong CF, Yuen KH, Peh KK
    Int J Pharm, 1999 Feb 01;178(1):11-22.
    PMID: 10205621
    Controlled release buccal patches were fabricated using Eudragit NE40D and studied. Various bioadhesive polymers, namely hydroxypropylmethyl cellulose, sodium carboxymethyl cellulose and Carbopol of different grades, were incorporated into the patches, to modify their bioadhesive properties as well as the rate of drug release, using metoprolol tartrate as the model drug. The in-vitro drug release was determined using the USP 23 dissolution test apparatus 5 with slight modification, while the bioadhesive properties were evaluated using texture analyzer equipment with chicken pouch as the model tissue. The incorporation of hydrophilic polymers was found to affect the drug release as well as enhance the bioadhesiveness. Although high viscosity polymers can enhance the bioadhesiveness of the patches, they also tend to cause non-homogeneous distribution of the polymers and drug, resulting in non-predictable drug-release rates. Of the various bioadhesive polymers studied, Cekol 700 appeared to be most satisfactory in terms of modifying the drug release and enhancement of the bioadhesive properties.
    Matched MeSH terms: Drug Delivery Systems*
  3. Winie T, Arof AK
    Spectrochim Acta A Mol Biomol Spectrosc, 2006 Mar 1;63(3):677-84.
    PMID: 16157506
    Fourier transform infrared (FT-IR) spectroscopic studies have been undertaken to investigate the interactions among components in a system of hexanoyl chitosan-lithium trifluoromethanesulfonate (LiCF(3)SO(3))-diethyl carbonate (DEC)/ethylene carbonate (EC). LiCF(3)SO(3) interacts with the hexanoyl chitosan to form a hexanoyl chitosan-salt complex that results in the shifting of the N(COR)(2), CONHR and OCOR bands to lower wavenumbers. Interactions between EC and DEC with LiCF(3)SO(3) has been noted and discussed. Evidence of interaction between EC and DEC has been obtained experimentally. Studies on polymer-plasticizer spectra suggested that there is no interaction between the polymer host and plasticizers. Competition between plasticizer and polymer on associating with Li(+) ions was observed from the spectral data for gel polymer electrolytes. The obtained spectroscopic data has been correlated with the conductivity performance of hexanoyl chitosan-based polymer electrolytes.
    Matched MeSH terms: Drug Delivery Systems
  4. Wong TW, Deepak KG, Taib MN, Anuar NK
    Int J Pharm, 2007 Oct 1;343(1-2):122-30.
    PMID: 17597317
    The capacity of microwave non-destructive testing (NDT) technique to characterize the matrix property of binary polymeric films for use as transdermal drug delivery system was investigated. Hydroxypropylmethylcellulose (HPMC) and polyethylene glycol (PEG) 3000 were the choice of polymeric matrix and plasticizer, respectively with loratadine as the model drug. Both blank and drug loaded HPMC-PEG 3000 films were prepared using the solvent-evaporation method. These films were conditioned at the relative humidity of 25, 50 and 75% prior to physicochemical characterization using the established methods of ultra-violet spectrophotometry, differential scanning calorimetry and Fourier transform infrared spectroscopy methods, as well as, novel microwave NDT technique. Blank films exhibited a greater propensity of polymer-polymer interaction at the O-H domain upon storage at a lower level of relative humidity, whereas drug loaded films exhibited a greater propensity of polymer-polymer, polymer-plasticizer and/or drug-polymer interaction via the O-H, C-H and/or aromatic C=C functional groups when they were stored at a lower or moderate level of relative humidity. The absorption and transmission characteristics of both blank and drug loaded films for microwave varied with the state of polymer-polymer, polymer-plasticizer, and/or drug-polymer interaction of the matrix. The measurements of microwave NDT test at 8 and 12 GHz were sensitive to the polar fraction of film involving functional group such as O-H moiety and the less polar environment of matrix consisting of functional groups such as C-H and aromatic C=C moieties. The state of interaction between polymer, plasticizer and/or drug of a binary polymeric film can be elucidated through its absorption and transmission profiles of microwave.
    Matched MeSH terms: Drug Delivery Systems
  5. Sudesh K, Loo CY, Goh LK, Iwata T, Maeda M
    Macromol Biosci, 2007 Nov 12;7(11):1199-205.
    PMID: 17703476
    Polyhydroxyalkanoates (PHAs) have attracted the attention of academia and industry because of their plastic-like properties and biodegradability. However, practical applications as a commodity material have not materialized because of their high production cost and unsatisfactory mechanical properties. PHAs are also believed to have high-value applications as an absorbable biomaterial for tissue engineering and drug-delivery devices because of their biocompatibility. However, research in these areas is still in its very early stages. The main problem faced by proponents of PHAs is the lack of a niche area where PHAs will be the most desired material in terms of its function during use rather than because of its eco-friendly virtues after use. Here, we report on the oil-absorbing property of PHA films and its potential applications. By comparing with some of the existing commercial products, the potential application of PHAs as cosmetic oil-blotting films is revealed for the first time. Besides having the ability to rapidly absorb and retain oil, PHA films also have a natural oil-indicator property, showing obvious changes in opacity following oil absorption. Surface analysis revealed that the surface structures such as porosity and smoothness exert great influence on the rapid oil-absorption properties of the PHA films. These newly discovered properties could be exploited to create a niche area for the practical applications of PHAs.
    Matched MeSH terms: Drug Delivery Systems
  6. Wong TW, Nurjaya S
    Eur J Pharm Biopharm, 2008 May;69(1):176-88.
    PMID: 17980563
    The effects of microwave irradiation on the drug release property of pectinate beads loaded internally with chitosan (chitosan-pectinate beads) were investigated against the pectinate beads and beads coacervated with chitosan externally (pectinate-chitosonium beads). These beads were prepared by an extrusion method using sodium diclofenac as the model water-soluble drug. The beads were subjected to microwave irradiation at 80 W for 5, 10, 21 and 40 min. The profiles of drug dissolution, drug content, drug-polymer interaction and polymer-polymer interaction were determined by drug dissolution testing, drug content assay, drug adsorption study, differential scanning calorimetry (DSC) and Fourier transform infra-red spectroscopy (FTIR) techniques. Treatment of pectinate beads by microwave did not lead to a decrease, but an increase in the extent of drug released at 4h of dissolution owing to reduced pectin-pectin interaction via the CO moiety of polymer. In addition, the extent of drug released from the pectinate beads could not be reduced merely through the coacervation of pectinate matrix with chitosan. The reduction in the extent of drug released from the pectinate-chitosonium beads required the treatment of these beads by microwave, following an increase in drug-polymer and polymer-polymer interaction in the matrix. The extent of drug released from the pectinate beads was reduced through incorporating chitosan directly into the interior of pectinate matrix, owing to drug-chitosan adsorption. Nonetheless, the treatment of chitosan-pectinate matrix by microwave brought about an increase in the extent of drug released unlike those of pectinate-chitosonium beads. Apparently, the loading of chitosan into the interior of pectinate matrix could effectively retard the drug release without subjecting the beads to the treatment of microwave. The microwave was merely essential to reduce the release of drug from pectinate beads when the chitosan was introduced to the pectinate matrix by means of coacervation. Under the influences of microwave, the drug release property of beads made of pectin and chitosan was mainly modulated via the CH, OH and NH moieties of polymers and drug, with CH functional group purported to retard while OH and NH moieties purported to enhance the drug released from the matrix.
    Matched MeSH terms: Drug Delivery Systems*
  7. Wong TW
    Recent Pat Drug Deliv Formul, 2009 Jan;3(1):8-25.
    PMID: 19149726 DOI: 10.2174/187221109787158346
    The global burden of diabetes is estimated to escalate from about 171 million in 2000 to 366 million people in 2030. The routine of diabetes treatment by injection of insulin incurs pain and has been one major factor negating the quality of life of diabetic patients. The possibility of administering insulin via alternative routes such as oral and nasal pathways has been investigated over the years, but with insulin experiencing risks of enzymatic degradation and poor transmucosal absorption. This leads to the rising needs to develop new formulation strategies emphasizing on the assembly of insulin and excipients into a physical structure to maintain the stability and increase the bioavailability of insulin. Chitosan and its derivatives or salts have been widely investigated as functional excipients of delivering insulin via oral, nasal and transdermal routes. The overview of various recent patented strategies on non-injection insulin delivery denotes the significance of chitosan for its mucoadhesive and able to protect the insulin from enzymatic degradation, prolong the retention time of insulin, as well as, open the inter-epithelial tight junction to facilitate systemic insulin transport. The chitosan can be employed to strengthen the physicochemical stability of insulin and multi-particulate matrix. The introduction of chitosan coat or co-formulation of chitosan with cationic gelatin or electrolytes which provide solidified or partially crosslinked structures retain and/or enhance the positive charges of dosage form necessary to induce mucoadhesiveness. The chitosan is modifiable chemically to produce water-soluble low molecular weight polymer which renders insulin able to be processed under mild conditions, and sulphated chitosan which markedly opens the paracellular channels for insulin transport. Combination of chitosan and fatty acid as hydrophobic nanoparticles promotes the insulin absorption via lymphoid tissue. Attainment of optimized formulations with higher levels of pharmacological bioavailability is deemed possible in future through targeted delivery of insulin using chitosan with specific adhesiveness to the intended absorption mucosa.
    Matched MeSH terms: Drug Delivery Systems
  8. Ling SS, Yuen KH, Magosso E, Barker SA
    J Pharm Pharmacol, 2009 Apr;61(4):445-9.
    PMID: 19298690 DOI: 10.1211/jpp/61.04.0005
    A liposome preparation that is amenable to receptor-mediated endocytosis has been developed to enhance the oral bioavailability of poorly absorbable peptidomimetic drugs by use of folic acid as the mediator of liposomal uptake.
    Matched MeSH terms: Drug Delivery Systems*
  9. Wong TW
    J Drug Target, 2010 Feb;18(2):79-92.
    PMID: 19968567 DOI: 10.3109/10611860903302815
    The possibility of administering insulin orally in replacement of painful subcutaneous route has been investigated over years but with varying degree of success. Nanoparticles, microparticles, hydrogel, capsule, tablet, and film patch are designed to deliver insulin orally. They are largely formulated with polymeric adhesive, protease inhibitor, insulin aggregation inhibitor, and functional excipients to induce transcellular, paracellular, Peyer's patches, or receptor-mediated transport of insulin in gastrointestinal tract. Superporous matrix, intestinal patches, and charged-coupled micromagnet microparticles are recent formulation strategies to promote oral insulin absorption. The formulation emphasizes on assembly of insulin and excipients into a physical structure which provides an element of drug targeting to maintain stability and increase bioavailability of insulin. The overview of various strategies applied in oral insulin delivery system design denotes the significance of mucoadhesiveness whereby a prolonged retention of dosage form in intestinal tract translates to cumulative insulin release and absorption, overcoming the intestinal transport capacity limit. Synthesis and use of mucoadhesive excipients, chemical modification of insulin to promote its physicochemical and biological stability for encapsulation in dosage form with prolonged retention characteristics and identification of potential insulin adjuncts are efforts needed to accelerate the speed of obtaining a functional oral insulin delivery system.
    Matched MeSH terms: Drug Delivery Systems*
  10. Anuar MS, Briscoe BJ
    Int J Pharm, 2010 Mar 15;387(1-2):42-7.
    PMID: 19963050 DOI: 10.1016/j.ijpharm.2009.11.031
    The predilection of a bi-layered tablet to fail in the interface region after its initial formation in the compaction process reduces its practicality as a choice for controlled release solid drug delivery system. Hence, a fundamental appreciation of the governing mechanism that causes the weakening of the interfacial bonds within the bi-layered tablet is crucial in order to improve the overall bi-layered tablet mechanical integrity. This work has shown that the occurrence of the elastic relaxation in the interface region during the ejection stage of the compaction process decreases with the increase in the bi-layered tablet interface strength. This is believed to be due to the increase in the plastic bonding in the interface region. The tablet diametrical elastic relaxation affects the tablet height elastic relaxation, where the impediment of the tablet height expansion is observed when the interface region experiences a diametrical expansion.
    Matched MeSH terms: Drug Delivery Systems*
  11. Barnard RT
    Expert Rev Vaccines, 2010 May;9(5):461-3.
    PMID: 20450319 DOI: 10.1586/erv.10.48
    The Recombinant Vaccines: Strategies for Candidate Discovery and Vaccine Delivery conference, organized by EuroSciCon, hosted a group of UK-based and international scientists from as far afield as Malaysia and Australia. Genomic analyses of pathogens and elucidation of mechanisms of pathogenesis has advanced candidate discovery and development of vaccines. Therefore, it was timely that this conference featured, in addition to detailed expositions of target selection and clinical trials, presentations on manufacturability, scale-up and delivery of vaccines. Ten talks were presented. This meeting report describes the key topics presented and the themes that emerged from this conference.
    Matched MeSH terms: Drug Delivery Systems
  12. Venkatesh G, Majid MI, Mansor SM, Nair NK, Croft SL, Navaratnam V
    Drug Dev Ind Pharm, 2010 Jun;36(6):735-45.
    PMID: 20136493 DOI: 10.3109/03639040903460446
    The aim of this study was to prepare a lipid-based self-microemulsifying drug delivery system (SMEDDS) to increase the solubility and oral bioavailability of a poorly water-soluble compound, buparvaquone (BPQ).
    Matched MeSH terms: Drug Delivery Systems/methods*
  13. Sakeena MH, Muthanna FA, Ghassan ZA, Kanakal MM, Elrashid SM, Munavvar AS, et al.
    J Oleo Sci, 2010;59(4):223-8.
    PMID: 20299769
    The aim of the present study is to formulate and investigate the potential of nanoemulsion formulation for topical delivery of ketoprofen. In this study, Palm Oil Esters (POEs) a newly introduced oil by Universiti Putra Malaysia researchers was chosen for the oil phase of the nanoemulsion, because the oil was reported to be a good vehicle for pharmaceutical use. Oil-in-water nanoemulsion was prepared by spontaneous emulsification method. The droplets size was studied by laser scattering spectroscopy (Nanophox) and Transmission Electron Microscopy (TEM). Franz diffusion cells were used, to determine the drug release and drug transferred through methyl acetate cellulose membrane (artificial membrane). The results of droplets size analysis shows the droplets are in the range of nanoemulsion which is below than 500 nm. The in vitro release profile shows a sufficient percentage of drugs released through the methyl acetate cellulose membrane. This initial study showed that the nanoemulsion formulated using POEs has great potential for topical delivery of ketoprofen.
    Matched MeSH terms: Drug Delivery Systems*
  14. Saravanan M, Bhaskar K, Maharajan G, Pillai KS
    J Drug Target, 2011 Feb;19(2):96-103.
    PMID: 20380621 DOI: 10.3109/10611861003733979
    We have previously reported on the targeting of diclofenac sodium in joint inflammation using gelatin magnetic microspheres. To overcome complications in the administration of magnetic microspheres and achieve higher targeting efficiency, the present work focuses on the formulation of gelatin microspheres for intra-articular administration. Drug-loaded microspheres were prepared by the emulsification/cross-linking method, characterized by drug loading, size distribution, scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), X-ray diffraction (XRD), gas chromatography, and in vitro release studies. The targeting efficiency of microspheres was studied in vivo in rabbits. The microspheres showed drug loading of 9.8, 18.3, and 26.7% w/w with an average size range of 37-46 µm, depending upon the drug-polymer ratio. They were spherical in nature and free from surface drug as evidenced by the SEM photographs. FT-IR, DSC, and XRD revealed the absence of drug-polymer interaction and amorphous nature of entrapped drug. Gas chromatography confirms the absences of residual glutaraldehyde. The formulated microspheres could prolong the drug release up to 30 days in vitro. About 81.2 and 43.7% of administered drug in the microspheres were recovered from the target joint after 1 and 7 days of postintra-articular injection, respectively, revealing good targeting efficiency.
    Matched MeSH terms: Drug Delivery Systems*
  15. Wong TW, Colombo G, Sonvico F
    AAPS PharmSciTech, 2011 Mar;12(1):201-14.
    PMID: 21194013 DOI: 10.1208/s12249-010-9564-z
    Colon cancer is the fourth most common cancer globally with 639,000 deaths reported annually. Typical chemotherapy is provided by injection route to reduce tumor growth and metastasis. Recent research investigates the oral delivery profiles of chemotherapeutic agents. In comparison to injection, oral administration of drugs in the form of a colon-specific delivery system is expected to increase drug bioavailability at target site, reduce drug dose and systemic adverse effects. Pectin is suitable for use as colon-specific drug delivery vehicle as it is selectively digested by colonic microflora to release drug with minimal degradation in upper gastrointestinal tract. The present review examines the physicochemical attributes of formulation needed to retard drug release of pectin matrix prior to its arrival at colon, and evaluate the therapeutic value of pectin matrix in association with colon cancer. The review suggests that multi-particulate calcium pectinate matrix is an ideal carrier to orally deliver drugs for site-specific treatment of colon cancer as (1) crosslinking of pectin by calcium ions in a matrix negates drug release in upper gastrointestinal tract, (2) multi-particulate carrier has a slower transit and a higher contact time for drug action in colon than single-unit dosage form, and (3) both pectin and calcium have an indication to reduce the severity of colon cancer from the implication of diet and molecular biology studies. Pectin matrix demonstrates dual advantages as drug carrier and therapeutic for use in treatment of colon cancer.
    Matched MeSH terms: Drug Delivery Systems
  16. Chitneni M, Peh KK, Darwis D, Abdulkarim M, Abdullah GZ, Qureshi MJ
    Pak J Pharm Sci, 2011 Apr;24(2):113-21.
    PMID: 21454158
    The objective of the present study was to determine the intestinal absorption of sulpiride incorporated into SMEDDS by means of single-pass intestinal perfusion method (SPIP) in rat and to compare the effective permeability coefficient obtained with that of drug solution and micellar solution. The prepared SMEDDS and micelles formulations were investigated for droplets size. SPIP experiment was performed using the three formulations in three of the secluded regions of the small intestine (duodenum, jejunum, and ileum). The amount of the drug in the samples was estimated by HPLC and the effective permeability coefficients in rats were calculated. The human intestinal permeability was predicted based on rat effective permeability coefficient value. The dilution stability of the formulations was also determined. The average droplet size of SMEDDS and micelles was 9.27 nm and 7.20 nm respectively. The effective permeability coefficient of sulpiride was appreciably lower in the ileum weighed against jejunum and duodenum when administered as a solution (P<0.05). The estimated human absorption of sulpiride for the SMEDDS dilutions was superior to that from solution (P<0.05) and similar to micellar solution. The micellar dilutions were unstable whereas the SMEDDS dilutions were stable. Based on the above results, SMEDDS can be a potential candidate for improving the peroral absorption of the sulpiride.
    Matched MeSH terms: Drug Delivery Systems
  17. Heidarpour F, Mohammadabadi MR, Zaidul IS, Maherani B, Saari N, Hamid AA, et al.
    Pharmazie, 2011 May;66(5):319-24.
    PMID: 21699064
    The oral route is considered the most patient-convenient means of drug administration. In recent years there has been a tendency to employ smart carrier systems that enable controlled or timed release of a bioactive material, thereby providing a better dosing pattern and minimizing side effects. Nano-encapsulation systems (nanocarriers) offer important advantages over conventional drug delivery techniques. Nanocarriers can protect the drug from chemical/enzymatic degradation and enhance bioavailability. Prebiotics are ideal ingredients for the nano-encapsulation and oral drug delivery due to their natural ability to protect the encapsulated compound in the upper gasterointestinal (GI) tract. Here the potential of prebiotics for oral delivery of drugs and other bioactives is reviewed.
    Matched MeSH terms: Drug Delivery Systems
  18. Ali RM, Degenhardt R, Zambahari R, Tresukosol D, Ahmad WA, Kamar Hb, et al.
    EuroIntervention, 2011 May;7 Suppl K:K83-92.
    PMID: 22027736 DOI: 10.4244/EIJV7SKA15
    Coronary lesions in diabetics (DM) are associated with a high recurrence following percutaneous coronary intervention (PCI), even after drug-eluting stent (DES) deployment. Encouraging clinical data of the drug-eluting balloon catheter (DEB) SeQuent Please warrant its investigation in these patients.
    Matched MeSH terms: Drug Delivery Systems/instrumentation*
  19. Chin K
    EuroIntervention, 2011 May;7 Suppl K:K43-6.
    PMID: 22027726 DOI: 10.4244/EIJV7SKA7
    In-stent restenosis remains an important issue even in the drug-eluting stent (DES) era today. In recent years, drug-eluting balloons (DEB) have emerged as a potential alternative to the treatment of in-stent restenosis. Paclitaxel was identified as the primary drug for DEB because of its rapid uptake and prolonged retention. Non-stent-based local drug delivery using DEB maintains the antiproliferation properties of DES, but without the limitations of DES such as subacute stent thrombosis, stent fractures, prolonged antiplatelet therapy and more importantly, avoiding a "stent-in-a-stent" approach. The first major impact of drug-eluting balloon (DEB) in the management of bare metal instent restenosis was the "PACCOCATH ISR I" randomised trial, comparing the efficacy of drug-eluting balloon versus uncoated balloon. The six months angiographic results showed a binary restenosis of 5% and 4% MACE in the drug-eluting balloon group, compared with 43% binary restenosis and 31% MACE, in the uncoated balloon group (p=0.002 and 0.02). The second major DEB trial is the "PEPCAD II Trial", comparing the efficacy of the SeQuent Please DEB with the Taxus drug-eluting stent in the treatment of bare-metal stent instent restenosis. At 6-month follow-up, in-segment late lumen loss was 0.38 ± 0.61 mm in the DES group versus 0.17 ± 0.42 mm (p=0.03) in the DEB group, resulting in a binary restenosis rate of 12/59 (20%) versus 4/57 (7%; p=0.06). At 12 months, MACE rates were 22% in the Taxus group and 9% in the DEB group (P=0.08). The TLR at 12 months was 15% in the Taxus group and 6% in the DEB group (p=0.15). Based on these two pivotal trials, the European Society of Cardiology Guidelines for Percutaneous Coronary Intervention (2010) recommended that DEB should be considered for the treatment of in-stent restenosis after prior bare-metal stent. This was accorded a class 2 IIa indication, with a level B evidence.
    Matched MeSH terms: Drug Delivery Systems/instrumentation*
  20. Choo GH
    EuroIntervention, 2011 May;7 Suppl K:K112-8.
    PMID: 22027720 DOI: 10.4244/EIJV7SKA19
    The drug-eluting balloon (DEB) is an exciting new technology that holds much promise. As an evolving technology undergoing intensive research, the device is being constantly refined and its numerous potential applications studied. Though initially created to fulfil specific needs in the coronary vasculature, there is great potential for its use in other vascular territories and structures including the management of valvular, congenital heart and neuro-interventional pathologies. In addition, the application of this device in conjunction with other existing technologies may enhance the clinical results.
    Matched MeSH terms: Drug Delivery Systems/instrumentation*; Drug Delivery Systems/trends
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links