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Sriamornsak P Asavapichayont P Nunthanid J Luangtana-Anan M Limmatvapirat S Piriyaprasarth S 《AAPS PharmSciTech》2008,9(2):571-576
The purpose of this study was to prepare wax-incorporated pectin-based emulsion gel beads using a modified emulsion-gelation
method. The waxes in pectin–olive oil mixtures containing a model drug, metronidazole, were hot-melted, homogenized and then
extruded into calcium chloride solution. The beads formed were separated, washed with distilled water and dried for 12 h.
The influence of various types and amounts of wax on floating and drug release behavior of emulsion gel beads of calcium pectinate
was investigated. The drug-loaded gel beads were found to float on simulated gastric fluid if the sufficient amount of oil
was used. Incorporation of wax into the emulsion gel beads affected the drug release. Water-soluble wax (i.e. polyethylene
glycol) increased the drug release while other water-insoluble waxes (i.e. glyceryl monostearate, stearyl alcohol, carnauba
wax, spermaceti wax and white wax) significantly retarded the drug release. Different waxes had a slight effect on the drug
release. However, the increased amount of incorporated wax in the formulations significantly sustained the drug release while
the beads remained floating. The results suggest that wax-incorporated emulsion gel beads could be used as a carrier for intragastric
floating drug delivery. 相似文献
2.
Sunee Techaarpornkul Sirirat Wongkupasert Praneet Opanasopit Auayporn Apirakaramwong Jurairat Nunthanid Uracha Ruktanonchai 《AAPS PharmSciTech》2010,11(1):64-72
The aim of this study was to investigate chitosan/siRNA complexes formulated with various chitosan salts (CS) including chitosan
aspartate (CS-Asp), chitosan glutamate (CS-Glu), chitosan acetate (CS-Ac), and chitosan hydrochloride (CS-HCl) for in vitro siRNA delivery into stable and constitutive enhanced green fluorescent protein (EGFP)-expressing HeLa cells. The CS/siRNA
complexes were characterized by 2% agarose gel electrophoresis and investigated for their transfection efficiency in stable
and constitutive EGFP-expressing HeLa cells. The cytotoxicity of the complexes was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl
tetrazolium bromide (MTT) assay. The formation of complexes CS/siRNA is mainly dependent on the weight ratio, whereas salt
form and molecular weight has less effect. The particle sizes of the complete complexes were in the range of 270–373 nm except
the complete complex of CS-Ac, with a slightly positive charge of less than 2 mV. The ability of CS to transfer functionally
active siRNA into cell culture is mainly dependent on the weight ratio and molecular weight of CS whereas salt form of CS
has less effect. The high gene-silencing efficiency was observed with low MW of CS (20 kDa) and high weight ratio of 32. Over
80% average cell viabilities were observed for CS/siRNA complexes in all weight ratios comparison to untreated cells. This
study suggests CS salts have the potential to be used as safe siRNA delivery vectors. 相似文献
3.
Manee Luangtana-anan Sontaya Limmatvapirat Jurairat Nunthanid Rapeepun Chalongsuk Keiji Yamamoto 《AAPS PharmSciTech》2010,11(3):1376-1382
Stability enhancement of protein-loaded chitosan microparticles under storage was investigated. Chitosan glutamate at 35 kDa
and bovine serum albumin as model protein drug were used in this study. The chitosan microparticles were prepared by ionotropic
gelation, and polyethylene glycol 200 (PEG 200) was applied after the formation of the particles. All chitosan microparticles
were kept at 25°C for 28 days. A comparison was made between those preparations with PEG 200 and without PEG 200. The changes
in the physicochemical properties of the microparticles such as size, zeta potential, pH, and percent loading capacity were
investigated after 0, 3, 7, 14, and 28 days of storage. It was found that the stability decreased upon storage and the aggregation
of microparticles could be observed for both preparations. The reduction in the zeta potential and the increase in the pH,
size, and loading capacity were observed when they were kept at a longer period. The significant change of those preparations
without PEG 200 was evident after 7 days of storage whereas those with PEG 200 underwent smaller changes with enhanced stability
after 28 days of storage. Therefore, this investigation gave valuable information on the stability enhancement of the microparticles.
Hence, enhanced stability of chitosan glutamate microparticles for the delivery of protein could be achieved by the application
of PEG 200. 相似文献
4.
Nathaya Wattanakorn Panida Asavapichayont Jurairat Nunthanid Sontaya Limmatvapirat Srisagul Sungthongjeen Doungdaw Chantasart Pornsak Sriamornsak 《AAPS PharmSciTech》2010,11(2):743-751
The objective of this study was to prepare and evaluate the pectin-based dosage form for buccal adhesion. Carbenoxolone sodium,
which is used for the treatment of aphthous ulcers in oral cavity, was used as a model drug. The pectin buccal discs were
prepared by direct compression. The water uptake and erosion of pectin disc increased progressively with the swelling time.
The bioadhesion of dried pectin discs decreased when either the discs were hydrated or the buccal tissue was wet with a small
volume of medium. The influencing factors such as pectin type, pectin to lactose ratio, and sweetener type on the formulations
were investigated. The results demonstrated that buccal discs prepared from pectin with a high degree of esterification (DE)
showed a weaker and more friable characteristic than that with low DE. Decreasing pectin to lactose ratio resulted in the
high dissolution rate with low bioadhesive properties. Addition of sweetener in the formulations also affected the hardness,
friability, and bioadhesive properties of the discs. The pectin discs containing sweetening agent showed a higher drug release
than those without sweetener. The results suggested that pectin-based bioadhesive discs could be used to deliver carbenoxolone
sodium in oral cavity. 相似文献
5.
This work was aimed at evaluating the effect of a pharmaceutical cationic exchange resin (Amberlite IRP-69) on the properties
of controlled release matrices using Methocel K4M (HPMC) or Ethocel 7cP (EC) as matrix formers. Diphenhydramine hydrochloride
(DPH), which was cationic and water soluble, was chosen as a model drug. HPMC- and EC-based matrices with varying amounts
(0–40%w/w) of resin incorporation were prepared by a direct compression. Matrix properties including diameter, thickness, hardness,
friability, surface morphology and drug release were evaluated. The obtained matrices were comparable in diameter and thickness
regardless of the amount of resin incorporation. Increasing the incorporated resin decreased the hardness of HPMC- and EC-based
matrices, correlating with the degree of rupturing on the matrix surfaces. The friability of HPMC-based matrices increased
with increasing the incorporated resin, corresponding to their decreased hardness. In contrast, the EC-based matrices showed
no significant change in friability in spite of decreasing hardness. The incorporated resin differently influenced DPH release
from HPMC- and EC-based matrices in deionized water. The resin further retarded DPH release from HPMC-based matrices due to
the gelling property of HPMC and the ion exchange property of the resin. In contrast, the release from EC-based matrices initially
increased because of the disintegrating property of the resin, but thereafter declined due to the complex formation between
released drug and dispersed resin via the ion exchange process. The release in ionic solutions was also described. In conclusion, the incorporated resin could alter the release and physical properties of matrices. 相似文献
6.
Pornsak Sriamornsak Jurairat Nunthanid Kamonrak Cheewatanakornkool Somkamol Manchun 《AAPS PharmSciTech》2010,11(3):1315-1319
Drug-loaded calcium pectinate gel (CaPG) beads were prepared by either mixing, absorption, or swelling method. The effects of drug loading method as well as the drug loading factors (i.e., drug concentration, soaking time in drug solution, type of solvent) on drug content and drug release were investigated. The amount of drug uptake (i.e., drug content) into CaPG beads increased as the initial drug concentration increased and varied depending on the loading method. The in vitro release studies in 0.1 N hydrochloric acid (HCl) and pH 6.8 buffer indicated that the drug loading method affected drug release and release parameter, time for 50% of drug release (T 50). The mixing method provided a faster drug release and lower T 50 than the absorption method and swelling method, respectively. This is probably due to higher drug content in CaPG beads. The increased concentration of drug in soaking solution and soaking time resulted in higher drug content and thus faster drug release (lower in T 50 values). When using 0.1 N HCl as solvent for soaking instead of water, the drug release was slower owing to the increase in molecular tortuosity of CaPG beads. The drug release was also affected by pH of the release medium in which drug release in 0.1 N HCl was faster than in pH 6.8 buffer. 相似文献
7.
Koonmee S Intapan PM Yamasaki H Sugiyama H Muto M Kuramochi T Kularbkeaw J Kanpittaya J Maleewong W Nawa Y 《Parasitology international》2011,60(4):460-464
PCR-based molecular diagnosis was made for the identification of causative agents of the clinically suspected pulmonary proliferative sparganosis case found in Thailand using formalin-fixed paraffin-embedded (FFPE) biopsy specimens. As a reference, FFPE biopsy specimen from a typical cutaneous sparganosis case was examined together. DNA samples were extracted from tissues and two partial fragments of cytochrome c oxidase subunit 1 (cox1) gene were amplified for the detection of Spirometra DNA. Two cox1 fragments were amplified successfully for both specimens. After alignment of nucleotide sequences of the PCR-amplicons, the causative agents of both cases were identified as Spirometra erinaceieuropaei. 相似文献
8.
Phromjai J Boonsaeng V Withyachumnarnkul B Flegel TW 《Diseases of aquatic organisms》2002,51(3):227-232
Hepatopancreatic parvovirus (HPV) infects the hepatopancreas in penaeid shrimp and retards their growth. The DNA sequence of HPV from Thai shrimp Penaeus monodon (HPVmon) differs from HPV of Penaeus chinensis (HPVchin) by approximately 30%. In spite of this difference, commercial PCR primers (DiagXotics) developed from HPVchin to yield a 350 bp PCR product do give a 732 bp product with HPVmon DNA template. On the other hand, the sensitivity of HPVmon detection with these primers and with hybridization probes designed for HPVchin is significantly lower than it is with HPVchin. To improve sensitivity for HPVmon detection, we used the sequence of the 732 bp HPVmon PCR amplicon described above to develop specific PCR primers (H441F and H441R) and hybridization probe. The primers could detect as little as 1 fg of purified HPVmon DNA while the 441 bp digoxygenin-labeled PCR product gave strong, specific reactions with in situ hybridization and with hybridization blots. In contrast, negative results were obtained using DNA from all other pathogens tested and from DNA of P. monodon. Supernatant solution from boiled, fresh shrimp fecal and postlarval samples homogenized in 0.025% NaOH/0.0125% SDS could be used to detect as little as 0.1 pg HPVmon DNA by the PCR reaction. By dot blot hybridization, a visible signal was obtained with purified HPVmon DNA at 0.01 pg, but detection in spiked feces and postlarval samples was only 1 and 0.1 pg, respectively. 相似文献
9.
Yotsanan Weerapol Sontaya Limmatvapirat Jurairat Nunthanid Pornsak Sriamornsak 《AAPS PharmSciTech》2014,15(2):456-464
A simple but novel mixed surfactant system was designed to fabricate a self-nanoemulsifying drug delivery system (SNEDDS) based on hydrophilic–lipophilic balance (HLB) value. The impacts of HLB and molecular structure of surfactants on the formation of SNEDDS were investigated. After screening various oils and surfactants, nifedipine (NDP)-loaded liquid SNEDDS was formulated with Imwitor® 742 as oil and Tween®/Span® or Cremophor®/Span® as mixed surfactant. Droplet size of the emulsions obtained after dispersing SNEDDS containing Tween®/Span® in aqueous medium was independent of the HLB of a mixed surfactant. The use of the Cremophor®/Span® blend gave nanosized emulsion at higher HLB. The structure of the surfactant was found to influence the emulsion droplet size. Solid SNEDDS was then prepared by adsorbing NDP-loaded liquid SNEDDS comprising Cremophor® RH40/Span® 80 onto Aerosil® 200 or Aerosil® R972 as inert solid carrier. Solid SNEDDS formulations using higher amounts (30–50% w/w) of Aerosil® 200 exhibited good flow properties with smooth surface and preserved the self-emulsifying properties of liquid SNEDDS. Differential scanning calorimetry and X-ray diffraction studies of solid SNEDDS revealed the transformation of the crystalline structure of NDP due to its molecular dispersion state. In vitro dissolution study demonstrated higher dissolution of NDP from solid SNEDDS compared with NDP powder. 相似文献
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