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Stereoselective release behaviors of imprinted bead matrices 总被引:2,自引:0,他引:2
Suedee R Srichana T Chotivatesin R Martin GP 《Drug development and industrial pharmacy》2002,28(5):545-554
In this work, the stereoselective release behaviors of “low”-swelling molecularly imprinted polymer (MIP) bead matrices in pressed-coat tablet type were studied. Either R-propranolol selective MIP or S-propranolol selective MIP was combined with excipients and racemic propranolol and fabricated into the matrix. Subsequently, the release of different propranolol enantiomers from the matrices was examined. Also, the microscopic structure of the hydrated “low”-swelling MIP matrix was determined using a cryogenic scanning electron microscope in order to compare with that of the hydrated “high”-swelling MIP matrix. In vitro release profiles of the “low”-swelling matrices showed a difference in the release of enantiomers, in that the non-template isomer was released faster than the template isomer. However, in the last phase of dissolution this difference reduced and later reversed, resulting at last in the type of specificity being similar to that obtained previously with “high”-swelling MIP matrices.
n summary, MIP beads can be fashioned into matrices and incorporated into different formulations to regulate the resultant stereoselectivity. From the behaviors of stereoselective release observed in MIP matrices, we can conclude that the enantioselective-controlled delivery mechanism of MIPs via formulations depends on the relative affinity of the enantiomer for the template sites, as well as the nature of the polymer, such as hydrophobicity and swellability. 相似文献
n summary, MIP beads can be fashioned into matrices and incorporated into different formulations to regulate the resultant stereoselectivity. From the behaviors of stereoselective release observed in MIP matrices, we can conclude that the enantioselective-controlled delivery mechanism of MIPs via formulations depends on the relative affinity of the enantiomer for the template sites, as well as the nature of the polymer, such as hydrophobicity and swellability. 相似文献
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Pornanong Aramwit Sorada Kanokpanont Titpawan Nakpheng Teerapol Srichana 《International journal of molecular sciences》2010,11(5):2200-2211
Silk sericin (SS) can accelerate cell proliferation and attachment; however, SS can be extracted by various methods, which result in SS exhibiting different physical and biological properties. We found that SS produced from various extraction methods has different molecular weights, zeta potential, particle size and amino acid content. The MTT assay indicated that SS from all extraction methods had no toxicity to mouse fibroblast cells at concentrations up to 40 μg/mL after 24 h incubation, but SS obtained from some extraction methods can be toxic at higher concentrations. Heat-degraded SS was the least toxic to cells and activated the highest collagen production, while urea-extracted SS showed the lowest cell viability and collagen production. SS from urea extraction was severely harmful to cells at concentrations higher than 100 μg/mL. SS from all extraction methods could still promote collagen production in a concentration-dependent manner, even at high concentrations that are toxic to cells. 相似文献
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Zikant Saenkasa Chaiyavat Chaiyasut Roongnapa Srichana Sirivipa Piyamongkol 《应用聚合物科学杂志》2007,103(4):2325-2330
The target of this study was to synthesize the molecularly imprinted polymers (MIPs) of L ‐phenylalanine as the solid phases for characterization of molecular adsorption by molecularly imprinted solid phase extraction (MISPE). These MIPs, in microscale, were synthesized using thermal (40°C)‐compared with thermal (65°C)‐initiated polymerization process. Itaconic acid was chosen as the functional monomers, and either ethylene glycol dimethacrylate or trimethylolpropane trimethacrylate (TRIM) was used as the cross linker and was compared together. The influences of several parameters on the properties of the MIPs were investigated, especially physical robustness from the percentage yields and molecular adsorption from the percentage recovery by MISPE. The best yields were obtained from polymers made using TRIM and thermal (65°C)‐initiated polymerization. However, there were no significant differences in molecular adsorption. It was concluded that these parameters can be considered to synthesize MIPs for chiral separation in advance steps such as other related chromatographic techniques. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2325–2330, 2007 相似文献
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Rojanarat W Changsan N Tawithong E Pinsuwan S Chan HK Srichana T 《International journal of molecular sciences》2011,12(7):4414-4434
The aims of this study were to develop proliposome powders containing isoniazid (INH) in a dry powder aerosol form. INH-proliposome powders were prepared by a spray drying method. Proliposome physicochemical properties were determined using cascade impactor, X-ray diffraction and differential scanning calorimetry. The toxicity of proliposomes to respiratory-associated cell lines and its potential to provoke immunological responses from alveolar macrophages (AM) were determined. Free INH and INH-proliposome bioactivities were tested in vitro and in AM infected with Mycobacterium bovis (M. bovis). Aerosolization properties of INH-proliposome powders at 60 L/min, the powders showed mass median aerodynamic diameters of 2.99-4.92 μm, with fine particle fractions (aerosolized particles less than 4.4 μm) of 15-35%. Encapsulation of INH was 18-30%. Proliposome formulations containing INH to mannitol ratios of 4:6 and 6:4 exhibited the greatest overlapping peak between the drug and mannitol. INH-proliposomes were evidently nontoxic to respiratory-associated cells, and did not activate AM to produce inflammatory mediators-including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and nitric oxide-at a toxic level. The efficacy of INH-proliposome against AM infected with M. bovis was significantly higher than that of free INH (p < 0.05). INH-proliposomes are potential candidates for an alternative tuberculosis treatment. 相似文献
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The purpose of this work was to examine the in vitro enantioselective dissolution of salbutamol from matrix tablets containing various chiral excipients, such as γ-cyclodextrin (γ-CD), heptakis (2,6-di-O-methyl)-β-cyclodextrin (DM-β-CD), sulfobutyl-β-cyclodextrin (SBE-β-CD), hydroxypropylmethylcellulose (HPMC), and egg albumin. In this study, two types of tablets were prepared; the coated tablet contained the complex of racemic salbutamol and cyclodextrin (γ-CD, DM-β-CD, and SBE-β-CD), and the uncoated tablet was composed of the drug with either HPMC or egg albumin. Subsequently, these formulations were evaluated for enantioselective release. The results revealed that the formulations containing either SBE-β-CD, HPMC, or egg albumin had no enantioselective release, while the formulation with DM-β-CD gave slightly different release of the two enantiomers at the end of the dissolution profile. The formulation containing γ-CD provided significant stereoselectivity throughout the dissolution profile. The release of the eutomer R-salbutamol was higher than that of the distomer S-salbutamol from the γ-CD tablet. In addition, the enantioselective interaction for the γ-CD inclusion complex was investigated by 1H-NMR (nuclear magnetic resonance) spectroscopy and gave evidence to support the enantioselectivity obtained on dissolution. 相似文献
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Sukanjana Kamlungmak Supagorn Rugmai Kittiya Tinpun Titpawan Nakpheng Teerapol Srichana 《应用聚合物科学杂志》2020,137(43):49325
This research was designed to develop thermoresponsive poloxamer (P407)–polyvinyl alcohol (PVA) hydrogels to deliver mupirocin nanoparticles for wound healing. The mupirocin nanoparticles containing drug and gelatin or poly (acrylic acid) were prepared by spray drying. The hydrogel phases were evaluated by small-angle X-ray scattering. An in vitro drug release study was performed and the antibacterial activity of mupirocin nanoparticles-loaded hydrogel (MLH) was evaluated. Fourier transform infrared and proton nuclear magnetic resonance spectrum spectra of the mupirocin nanoparticles indicated a weak interaction between mupirocin and the carriers of carbopol and gelatin. The mupirocin molecules were surrounded by the carrier molecules. The MLH appeared to exhibit single diamond (Fd3m) phase behavior similar to P407 and the hydrogel base. The release of MLH in vitro indicated first-order kinetics (R2 = .9839–.8868). The MLH showed lower minimum inhibitory concentrations and minimum bactericidal concentrations against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Escherichia coli than mupirocin ointment. 相似文献
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Aramwit P Muangman P Namviriyachote N Srichana T 《International journal of molecular sciences》2010,11(8):2864-2874
A variety of silver-coated dressings and some impregnated with other chemicals are now available in the market; however, there have been few studies analyzing their comparative efficacies as antimicrobial agents. Moreover, their properties for retaining an appropriate level of moisture that is critical for effective wound healing have never been reported. Five commercially available silver-containing and chlorhexidine dressings, Urgotul SSD®, Bactigras®, Acticoat®, Askina Calgitrol Ag® and Aquacel Ag®, were tested to determine their comparative antimicrobial effectiveness in vitro against five common wound pathogens, namely methicillin-sensitive and -resistant Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. Mepitel®, a flexible polyamide net coated with soft silicone, was used as a control. The zones of inhibition and both the rapidity and the extent of killing of these pathogens were evaluated. All five antimicrobial dressings investigated exerted some bactericidal activity, particularly against E. coli. The spectrum and rapidity of action ranged widely for the different dressings. Acticoat® had a broad spectrum of action against both Gram-positive and -negative bacteria. Other dressings demonstrated a narrower range of bactericidal activities. Regarding the absorption and release of moisture, Askina Calgitrol Ag® absorbed and released the most moisture from the environment. Aquacel Ag® also exhibited good moisture absorption and moisture release, but to a lower degree. The other tested dressings absorbed or released very little moisture. Askina Calgitrol Ag® and Aquacel Ag® are good alternative dressings for treating wounds with high exudates and pus. An understanding of the characteristics of these dressings will be useful for utilizing them for specific requirements under specified conditions. 相似文献
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Pornanong Aramwit Nipaporn Bang Teerapol Srichana 《Food research international (Ottawa, Ont.)》2010,43(4):1093-1097
Mulberry fruit is well known as a good source of anthocyanins with many biological activities. However, there are several colors of mulberry fruits, even from the same species, which may generate different amounts of anthocyanins. This study investigates anthocyanin content and antioxidant levels as well as tyrosinase inhibition activity in the extract from various colors of mulberry fruit, Morus alba. The effects of heat and light, which the extract may be exposed to during food processing, on anthocyanin and antioxidant activities are also evaluated. Our results show that purple-colored mulberry fruit extract contains the highest levels of anthocyanin and strongest antioxidant as well as anti-tyrosinase properties compared with other colors mulberry fruit extracts. Light or heat exposure by incubation of the mulberry fruit extract at 70 °C for 10 h significantly deteriorated total anthocyanin and ascorbic acid content and led to a corresponding increase of the IC50 values. 相似文献
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