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1.
Article in English | MEDLINE | ID: mdl-38928976

ABSTRACT

A recent study conducted in Khon Kaen Province, Thailand, evaluated the effectiveness of a technology-assisted intervention aimed at improving water quality and addressing related health issues in communities around key water bodies. The intervention targeted health concerns associated with water contamination, including chronic kidney diseases, skin conditions, hypertension, and neurological symptoms. The study included water quality assessments and health evaluations of 586 residents and implemented a Learning Innovation Platform (LIP) across 13 communities. Results showed significant improvements in the community, including a decrease in hypertension and skin-related health issues, as well as enhanced community awareness and proficiency in implementing simple water quality assessments and treatment. The study demonstrated the value of a comprehensive, technology-driven community approach, effectively enhancing water quality and health outcomes, and promoting greater community awareness and self-sufficiency in managing environmental health risks.


Subject(s)
Water Quality , Thailand , Humans , Female , Male , Adult , Water Pollution , Middle Aged , Skin Diseases/therapy
2.
Carbohydr Polym ; 340: 122304, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-38858008

ABSTRACT

The high vaporization enthalpy of water attributed to the strong hydrogen bonds between water molecules is limiting the performance of solar evaporators. This work demonstrates a deliberate attempt to significantly reduce the vaporization enthalpy of water through the introduction of weak water-amine hydrogen bond interactions in hydrogel evaporators. In this article, bio-based chitosan-agarose/multiwalled carbon nanotube hydrogel film evaporators (CAMFEs) exhibit larger vaporization enthalpy reduction with the presence of primary amine groups in chitosan. An interplay between vaporization enthalpy reduction and water diffusivity leads to an optimal ratio of chitosan to agarose = 7:1 (CAMFE7) showing an impressive evaporation rate of 4.13 kg m-2 h-1 under 1 sun irradiation. CAMFE7 also exhibits excellent salt resistance, with a stable water evaporation rate, using brine water of up to 10 % salinity under continuous 1 sun irradiation. The high mechanical robustness together with its scalability makes CAMFE7 a highly promising material for practical drinking water production.

3.
Nanomaterials (Basel) ; 13(20)2023 Oct 22.
Article in English | MEDLINE | ID: mdl-37887954

ABSTRACT

Selenium nanoparticles (SeNPs) are worthy of attention and development for nutritional supplementation due to their health benefits in both animals and humans with low toxicity, improved bioavailability, and controlled release, being greater than the Se inorganic and organic forms. Our previous study reported that Anoectochilus burmannicus extract (ABE)-synthesized SeNPs (ABE-SeNPs) exerted antioxidant and anti-inflammatory activities. Furthermore, ABE could stabilize and preserve the biological activities of SeNPs. To promote the ABE-SeNPs as supplementary and functional foods, it was necessary to carry out a safety assessment. Cytotoxicity testing showed that SeNPs and ABE-SeNPs were harmless with no killing effect on Caco2 (intestinal epithelial cells), MRC-5 (lung fibroblasts), HEK293 (kidney cells), LX-2 (hepatic stellate cells), and 3T3-L1 (adipocytes), and were not toxic to isolated human PBMCs and RBCs. Genotoxicity assessments found that SeNPs and ABE-SeNPs did not induce mutations in Salmonella typhimurium TA98 and TA100 (Ames test) as well as in Drosophila melanogaster (somatic mutation and recombination test). Noticeably, ABE-SeNPs inhibited mutation in TA98 and TA100 induced by AF-2, and in Drosophila induced by urethane, ethyl methanesulfonate, and mitomycin c, suggesting their anti-mutagenicity ability. This study provides data that support the safety and anti-genotoxicity properties of ABE-SeNPs for the further development of SeNPs-based food supplements.

4.
Materials (Basel) ; 16(14)2023 Jul 22.
Article in English | MEDLINE | ID: mdl-37512437

ABSTRACT

With the help of laser ablation, a technology for obtaining nanosized crystalline selenium particles (SeNPs) has been created. The SeNPs do not exhibit significant toxic properties, in contrast to molecular selenium compounds. The administration of SeNPs can significantly increase the viabilities of SH-SY5Y and PCMF cells after radiation exposure. The introduction of such nanoparticles into the animal body protects proteins and DNA from radiation-induced damage. The number of chromosomal breaks and oxidized proteins decreases in irradiated mice treated with SeNPs. Using hematological tests, it was found that a decrease in radiation-induced leukopenia and thrombocytopenia is observed when selenium nanoparticles are injected into mice before exposure to ionizing radiation. The administration of SeNPs to animals 5 h before radiation exposure in sublethal and lethal doses significantly increases their survival rate. The modification dose factor for animal survival was 1.2. It has been shown that the introduction of selenium nanoparticles significantly normalizes gene expression in the cells of the red bone marrow of mice after exposure to ionizing radiation. Thus, it has been demonstrated that SeNPs are a new gene-protective and radioprotective agent that can significantly reduce the harmful effects of ionizing radiation.

5.
Nutrients ; 15(4)2023 Feb 17.
Article in English | MEDLINE | ID: mdl-36839375

ABSTRACT

Anoectochilus burmannicus is an orchid that contains phenolic compounds and exhibits antioxidant and anti-inflammation properties. This study aimed to investigate whether its ethanolic extract (ABE) can be used as a reducing agent and/or a stabilizer of nano-selenium (SeNP) synthesis. SeNPs exhibited higher antioxidant activity than ABE-SeNPs. In contrast, ABE-SeNP (4 µM Se) had greater anti-inflammatory activity in LPS-induced macrophages than SeNPs. Interestingly, ABE acted as a stabilizer for SeNPs by preventing particle aggregation and preserving its antioxidant activity after long-term storage (90 days). Moreover, after the freeze-drying process, ABE-SeNPs could be completely reconstituted to suspension with significantly stable antioxidant and anti-inflammatory activities compared to freshly prepared particles, suggesting the cryoprotectant and/or lyoprotectant role of ABE. The present study shows the potential of ABE as an effective stabilizer for nanoparticles and provides evidence for the development of ABE-SeNPs as a food supplement or novel functional ingredient for health benefits.


Subject(s)
Nanoparticles , Selenium , Antioxidants/pharmacology , Selenium/pharmacology , Anti-Inflammatory Agents
6.
Nanomaterials (Basel) ; 12(15)2022 Jul 29.
Article in English | MEDLINE | ID: mdl-35957037

ABSTRACT

Selenium nanoparticles (SeNPs) were synthesized to overcome the limitations of selenium, such as its narrow safe range and low water solubility. SeNPs reduce the toxicity and improve the bioavailability of selenium. Chitosan-coated SeNPs (Cs-SeNPs) were developed to further stabilize SeNPs and to test their effects against glioma cells. The effects of Cs-SeNPs on cell growth were evaluated in monolayer and 3D-tumor spheroid culture. Cell migration and cell invasion were determined using a trans-well assay. The effect of Cs-SeNPs on chemotherapeutic drug 5-fluorouracil (5-FU) sensitivity of glioma cells was determined in tumor spheroids. An in vitro blood-brain barrier (BBB) model was established to test the permeability of Cs-SeNPs. SeNPs and Cs-SeNPs can reduce the cell viability of glioma cells in a dose-dependent manner. Compared with SeNPs, Cs-SeNPs more strongly inhibited 3D-tumor spheroid growth. Cs-SeNPs exhibited stronger effects in inhibiting cell migration and cell invasion than SeNPs. Improved 5-FU sensitivity was observed in Cs-SeNP-treated cells. Cellular uptake in glioma cells indicated a higher uptake rate of coumarin-6-labeled Cs-SeNPs than SeNPs. The capability of coumarin-6 associated Cs-SeNPs to pass through the BBB was confirmed. Taken together, Cs-SeNPs provide exceptional performance and are a potential alternative therapeutic strategy for future glioma treatment.

7.
Mater Sci Eng C Mater Biol Appl ; 34: 377-83, 2014 Jan 01.
Article in English | MEDLINE | ID: mdl-24268272

ABSTRACT

Herein, we prepared PEI-immobilized core-shell particles possessing various types of polymer cores via a visible light-induced surfactant-free emulsion polymerization (SFEP) of three vinyl monomers: styrene (St), methyl methacrylate (MMA), and 2-hydroxyethyl methacrylate (HEMA). An effect of monomers on the polymerization and characteristics of resulting products was investigated. Monomers with high polarity can provide high monomer conversion, high percentage of grafted PEI, stable particles with uniform size distribution but less amino groups per particles. All prepared nanoparticles exhibited a core-shell nanostructure, containing PEI on the shell with hydrodynamic size around 140-230nm. For in-vitro study in Caco-2 cells, we found that the incorporation of PEI into these core-shell nanoparticles can significantly reduce its cytotoxic effect and also be able to internalized within the cells. Accordingly, these biocompatible particles would be useful for various biomedical applications, including gene transfection and intracellular drug delivery.


Subject(s)
Biocompatible Materials/chemistry , Materials Testing/methods , Nanoparticles/chemistry , Polyethyleneimine/chemistry , Polyethyleneimine/chemical synthesis , Caco-2 Cells , Cell Survival , Emulsions , Humans , Intracellular Space/metabolism , Methacrylates/chemistry , Methylmethacrylates/chemistry , Nanoparticles/ultrastructure , Polymerization , Polystyrenes/chemistry , Spectroscopy, Fourier Transform Infrared , Static Electricity , Surface Properties , Surface-Active Agents/chemistry
8.
Carbohydr Polym ; 92(1): 321-7, 2013 Jan 30.
Article in English | MEDLINE | ID: mdl-23218301

ABSTRACT

In this study two types of water-soluble ßCD grafted chitosan were synthesized and compared based on similar degree of N-substitution of ßCD moiety; QCD23-g-CS contained methylene spacer and QCDCA22-g-CS contained citric acid spacer. The QCD23-g-CS demonstrated greater eugenol (EG) encapsulation efficiency than that of QCDCA22-g-CS. The micelle-like assemblies of QCD23-g-CS led to slower release of EG while it did not observe in case of QCDCA22-g-CS. It was found that EG could absorb on chitosan backbone according to in silico modeling. Cytotoxicity of both derivatives against buccal mucosa cell is concentration-dependent. The QCDCA22-g-CS demonstrated stronger mucoadhesive response than that of QCD23-g-CS, due to hydrogen bonding according to mucin particle and SPR methods. Our results revealed that the spacer on both derivatives played an important role on binding affinity with EG, releasing profile and mucoadhesive property. These derivatives could be considered as promising carriers for mucosal delivery system.


Subject(s)
Chitosan/chemistry , Cyclodextrins/chemistry , Eugenol/chemistry , Cell Line/drug effects , Chitosan/chemical synthesis , Chitosan/pharmacology , Cyclodextrins/chemical synthesis , Cyclodextrins/pharmacology , Drug Delivery Systems , Eugenol/chemical synthesis , Humans , Hydrogen Bonding , Micelles , Mouth Mucosa/cytology , Mouth Mucosa/drug effects , Mucins/chemistry , Particle Size , Water/chemistry
9.
Carbohydr Polym ; 90(3): 1323-9, 2012 Oct 15.
Article in English | MEDLINE | ID: mdl-22939347

ABSTRACT

In this study, we examined the potential of cationic nanoparticle - polyethyleneimine-introduced chitosan shell/poly (methyl methacrylate) core nanoparticles (CS-PEI) for siRNA delivery. Initially, DNA delivery was performed to validate the capability of CS-PEI for gene delivery in the human cervical cancer cell line, SiHa. siRNA delivery were subsequently carried out to evaluate the silencing effect on targeted E6 and E7 oncogenes. Physicochemical properties including size, zeta potential and morphology of CS-PEI/DNA and CS-PEI/siRNA complexes, were analyzed. The surface charges and sizes of the complexes were observed at different N/P ratios. The hydrodynamic sizes of the CS-PEI/DNA and CS-PEI/siRNA were approximately 300-400 and 400-500nm, respectively. Complexes were positively charged depending on the amount of added CS-PEI. AFM images revealed the mono-dispersed and spherical shapes of the complexes. Gel retardation assay confirmed that CS-PEI nanoparticles completely formed complexes with DNA and siRNA at a N/P ratio of 1.6. For DNA transfection, CS-PEI provided the highest transfection result. Localization of siRNA delivered through CS-PEI was confirmed by differential interference contrast (DIC) confocal imaging. The silencing effect of siRNA specific to HPV 16 E6/E7 oncogene was examined at 18 and 24h post-transfection. The results demonstrated the capacity of CS-PEI to suppress the expression of HVP oncogenes.


Subject(s)
Gene Silencing , Human papillomavirus 16/metabolism , Methylmethacrylate/chemistry , Nanoparticles/chemistry , Oncogene Proteins, Viral/biosynthesis , Papillomavirus E7 Proteins/biosynthesis , Papillomavirus Infections/metabolism , Polyethyleneimine/chemistry , RNA, Small Interfering/chemistry , Repressor Proteins/biosynthesis , Uterine Cervical Neoplasms/metabolism , Cell Line, Tumor , Female , Gene Expression Regulation, Neoplastic/drug effects , Gene Expression Regulation, Neoplastic/genetics , Gene Expression Regulation, Viral/drug effects , Gene Expression Regulation, Viral/genetics , Human papillomavirus 16/genetics , Humans , Methylmethacrylate/pharmacology , Oncogene Proteins, Viral/genetics , Papillomavirus E7 Proteins/genetics , Papillomavirus Infections/genetics , Papillomavirus Infections/pathology , Papillomavirus Infections/therapy , Papillomavirus Infections/virology , Particle Size , Polyethyleneimine/pharmacology , RNA, Small Interfering/pharmacology , Repressor Proteins/genetics , Uterine Cervical Neoplasms/genetics , Uterine Cervical Neoplasms/pathology , Uterine Cervical Neoplasms/therapy , Uterine Cervical Neoplasms/virology
10.
Int J Nanomedicine ; 7: 2783-92, 2012.
Article in English | MEDLINE | ID: mdl-22701321

ABSTRACT

BACKGROUND: The purpose of this study was to demonstrate the potential of magnetic poly(methyl methacrylate) (PMMA) core/polyethyleneimine (PEI) shell (mag-PEI) nanoparticles, which possess high saturation magnetization for gene delivery. By using mag-PEI nanoparticles as a gene carrier, this study focused on evaluation of transfection efficiency under magnetic induction. The potential role of this newly synthesized nanosphere for therapeutic delivery of the tryptophan hydroxylase-2 (TPH-2) gene was also investigated in cultured neuronal LAN-5 cells. METHODS: The mag-PEI nanoparticles were prepared by one-step emulsifier-free emulsion polymerization, generating highly loaded and monodispersed magnetic polymeric nanoparticles bearing an amine group. The physicochemical properties of the mag-PEI nanoparticles and DNA-bound mag-PEI nanoparticles were investigated using the gel retardation assay, atomic force microscopy, and zeta size measurements. The gene transfection efficiencies of mag-PEI nanoparticles were evaluated at different transfection times. Confocal laser scanning microscopy confirmed intracellular uptake of the magnetoplex. The optimal conditions for transfection of TPH-2 were selected for therapeutic gene transfection. We isolated the TPH-2 gene from the total RNA of the human medulla oblongata and cloned it into an expression vector. The plasmid containing TPH-2 was subsequently bound onto the surfaces of the mag-PEI nanoparticles via electrostatic interaction. Finally, the mag-PEI nanoparticle magnetoplex was delivered into LAN-5 cells. Reverse-transcriptase polymerase chain reaction was performed to evaluate TPH-2 expression in a quantitative manner. RESULTS: The study demonstrated the role of newly synthesized high-magnetization mag-PEI nanoparticles for gene transfection in vitro. The expression signals of a model gene, luciferase, and a therapeutic gene, TPH-2, were enhanced under magnetic-assisted transfection. An in vitro study in neuronal cells confirmed that using mag-PEI nanoparticles as a DNA carrier for gene delivery provided high transfection efficiency with low cytotoxicity. CONCLUSION: The mag-PEI nanoparticle is a promising alternative gene transfection reagent due to its ease of use, effectiveness, and low cellular toxicity. The mag-PEI nanoparticle is not only practical for gene transfection in cultured neuronal cells but may also be suitable for transfection in other cells as well.


Subject(s)
Imines/chemistry , Magnetite Nanoparticles/chemistry , Neuroblastoma/genetics , Neuroblastoma/therapy , Polyethylenes/chemistry , Polymethyl Methacrylate/chemistry , Transfection/methods , Cell Line, Tumor , Cell Survival , Electrophoretic Mobility Shift Assay , Humans , Medulla Oblongata/chemistry , Medulla Oblongata/enzymology , Neuroblastoma/chemistry , Particle Size , Reverse Transcriptase Polymerase Chain Reaction , Tryptophan Hydroxylase/genetics , Tryptophan Hydroxylase/metabolism
11.
Int J Biol Macromol ; 48(4): 589-95, 2011 May 01.
Article in English | MEDLINE | ID: mdl-21300088

ABSTRACT

Water-soluble ß-cyclodextrin grafted with chitosan (CD-g-CS) was carried out by quaternizing the CD-g-CS with glycidyltrimethyl ammonium chloride (GTMAC) under mild acidic condition, corresponding to the quaternized CD-g-CS (QCD-g-CS). The degrees of substitution (DS) and quaternization (DQ), ranging from 5% to 23% and 66% to 80%, respectively, were determined by (1)H NMR spectroscopy. Self-aggregates formation of all QCD-g-CSs were investigated in water using dynamic light scattering (DLS), atomic force microscopy (AFM), and transmission electron microscopy (TEM) techniques. The result revealed that all QCD-g-CSs are able to form self-aggregates in water. Large particle sizes ranged from 800 to 3000nm were obtained by DLS while zeta-potentials were ranging from 25 to 40mV. AFM and TEM depicted a spherical shape with particle sizes ranging from 100 to 900nm. Mucoadhesive and cytotoxic properties of all QCD-g-CSs were evaluated using a mucin particle method and MTT assay compared to quaternized chitosan (QCS). It was found that the mucoadhesive property increased with decreasing DS due to less quaternary ammonium moiety into the chitosan backbone. On the other hand, the cytotoxicity increased with increasing DS even though the DQ is decreased.


Subject(s)
Chitosan/chemistry , Mucins/chemistry , beta-Cyclodextrins/chemistry , Adhesiveness , Epoxy Compounds , Magnetic Resonance Spectroscopy , Microscopy, Atomic Force , Microscopy, Electron, Transmission , Particle Size , Quaternary Ammonium Compounds , Spectroscopy, Fourier Transform Infrared , Water/chemistry
12.
Talanta ; 84(1): 89-97, 2011 Mar 15.
Article in English | MEDLINE | ID: mdl-21315903

ABSTRACT

Novel immunomagnetic particles have been prepared for separation of CD4(+) lymphocytes. The magnetic nanoparticles with a diameter of approximately 5-6 nm were first synthesized by co-precipitation from ferrous and ferric iron solutions and subsequently encapsulated with poly(glycidyl methacrylate) (PGMA) by precipitation polymerization. Monoclonal antibody specific to CD4 molecules expressed on CD4(+) lymphocytes was conjugated to the surface of magnetic PGMA particles through covalent bonding between epoxide functional groups on the particle surface and primary amine groups of the antibodies. The generated immunomagnetic particles have successfully separated CD4(+) lymphocytes from whole blood with over 95% purity. The results indicated that these particles can be employed for cell separation and provide a strong potential to be applied in various biomedical applications including diagnosis, and monitoring of human diseases.


Subject(s)
Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/immunology , CD4 Antigens/immunology , CD4-Positive T-Lymphocytes/cytology , Immunomagnetic Separation/methods , Magnetics , Polymethacrylic Acids/chemistry , Animals , Ferric Compounds/chemistry , Humans , Immunomagnetic Separation/economics , Nanoparticles/chemistry , Oleic Acid/chemistry
13.
J Biomater Sci Polym Ed ; 21(11): 1515-32, 2010.
Article in English | MEDLINE | ID: mdl-20537238

ABSTRACT

This study intended to prepare iron oxide nanoparticle-entrapped chitosan (CS) nanoparticles for stem cell labeling. The nanoparticles were synthesized by polymerizing iron oxide nanoparticle-associated methacrylic acid monomer in the presence of CS. TEM revealed that the well-defined iron oxide nanoparticles were successfully encapsulated inside the CS nanoparticles. The effect of CS at different [NH(2)]/[COOH] molar ratios on particle size, surface charge, thermal stability and magnetic properties was determined systematically. Internalization and localization of the coated nanoparticles were evaluated by atomic absorption spectrometry and confocal laser scanning microscopy. The Kusa O cell line was chosen as a stem cell model. Interestingly, the uptake of iron oxide-entrapped CS nanoparticles was remarkably enhanced under magnetization and the nanoparticles were mostly located inside cellular compartments. It can be concluded that the iron oxide-entrapped CS nanoparticles have a strong potential for stem cell labeling.


Subject(s)
Chitosan/chemistry , Ferric Compounds/chemistry , Nanoparticles/chemistry , Staining and Labeling/methods , Stem Cells/cytology , Animals , Cell Line , Mice , Microscopy, Electron, Transmission , Nanotechnology/methods , Stem Cells/ultrastructure
14.
Colloids Surf B Biointerfaces ; 77(2): 219-26, 2010 Jun 01.
Article in English | MEDLINE | ID: mdl-20189779

ABSTRACT

The core-shell nanoparticles possessing poly(methyl methacrylate) (PMMA) core coated with chitosan (CS), polyethyleneimine (PEI), and chitosan-mixed-polyethyleneimine (CS/PEI) shells were synthesized in this work. The emulsifier-free emulsion polymerization triggered by a redox initiating system from t-butylhydroperoxide (TBHP) and amine groups on CS and/or PEI was used as a synthetic method. In the CS/PEI systems, the amount of CS was kept constant (0.5g), while the amount of PEI was varied from 0.1 to 0.5g. The surface and physico-chemical properties of prepared nanoparticles were then examined. FTIR spectra indicated the presence of grafted PMMA on CS and/or PEI, and the weight fraction of incorporated PEI in the CS/PEI nanoparticles. All nanoparticles were spherical in shape with uniform size distribution illustrated by scanning electron microscopy (SEM). The introduction of PEI to CS nanoparticles yielded the higher monomer conversion, grafting efficiency, and grafting percentage compared with the CS nanoparticles. The size of CS/PEI nanoparticles was smaller than the original CS and PEI nanoparticles, and tended to decrease with increasing amount of PEI introduced. The introduction of PEI also brought the higher colloidal stability to the nanoparticles as indicated by zeta-potential measurement and isoelectric point analysis. The nanoparticles exhibited a promising antibacterial activity against Staphylococcus aureus and Escherichia coli. The nanoparticle-bacteria interaction was studied via SEM. The results suggested that they would be useful as effective antibacterial agents.


Subject(s)
Anti-Infective Agents/chemistry , Chitosan/chemistry , Nanoparticles/chemistry , Nanotechnology/methods , Polyethyleneimine/chemistry , Polymethyl Methacrylate/chemistry , Anti-Infective Agents/pharmacology , Biopterins/analogs & derivatives , Biopterins/chemistry , Escherichia coli/metabolism , Isoelectric Point , Microbial Sensitivity Tests , Microscopy, Electron, Scanning/methods , Models, Chemical , Spectroscopy, Fourier Transform Infrared , Staphylococcus aureus/metabolism , Time Factors
15.
J Biomater Sci Polym Ed ; 21(2): 205-23, 2010.
Article in English | MEDLINE | ID: mdl-20092685

ABSTRACT

This work investigated polyethyleneimine (PEI)-introduced chitosan (CS) (CS/PEI) nanoparticles as non-viral carrier of plasmid DNA for rat mesenchymal stem cells (MSCs). The CS/PEI nanoparticles were prepared by the emulsifier-free emulsion polymerization of methyl methacrylate monomer induced by a small amount of t-butyl hydroperxide in the presence of different concentrations of PEI mixed with CS. The resulting nanoparticles were characterized by their surface properties and buffering capacity. In vitro gene transfection was also evaluated. The introduction of PEI affected the surface charge, dispersing stability and buffering capacity of the nanoparticles. The CS/PEI nanoparticles formed a complex upon mixing with a plasmid DNA of luciferase. The complex enhanced the level of gene transfection and prolonged the time period of expression for MSCs, compared with those of plasmid DNA-original CS and PEI nanoparticles. Cytotoxicity of CS/PEI complexes with plasmid DNA was significantly low, depending on the amount of PEI introduced. It is concluded that the CS/PEI nanoparticle was a promising carrier for gene delivery of MSCs.


Subject(s)
Chitosan/chemistry , Chitosan/metabolism , Mesenchymal Stem Cells/metabolism , Nanoparticles/chemistry , Polyethyleneimine/chemistry , Polymethyl Methacrylate/chemistry , Transfection/methods , Amines/chemistry , Animals , Buffers , DNA/genetics , DNA/metabolism , Emulsions , Male , Particle Size , Rats , Rats, Wistar , Surface Properties , Time Factors , Trinitrobenzenesulfonic Acid/chemistry
16.
Macromol Biosci ; 9(10): 1004-15, 2009 Oct 08.
Article in English | MEDLINE | ID: mdl-19530128

ABSTRACT

Gelatin hydrogel pads have been prepared from a 10 wt.-% gelatin solution that contained 2.5 wt.-% AgNO(3) in 70% v/v acetic acid by a solvent-casting technique. The AgNO(3)-containing gelatin solution was aged under mechanical stirring for various time intervals to allow for the formation of silver nanoparticles (nAgs). The formation of nAgs was monitored by a UV-vis spectrophotometer. The morphology and size of the nAgs were characterized by transmission electron microscopy (TEM). To improve the water resistance of the hydrogels, various contents of glutaraldehyde (GTA) were added to the AgNO(3)-containing gelatin solution to cross-link the obtained gelatin hydrogels. These hydrogels were tested for their water retention and weight loss behavior, release characteristics of the as-loaded silver, and antibacterial activity against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. The AgNO(3)-containing gelatin solution that had been aged for 5 d showed the greatest number of nAgs formed. The size of these particles, based on TEM results, was 10-11 nm. With an increase in the GTA content used to cross-link the hydrogels, the water retention, the weight loss, and the cumulative amount of silver released were found to decrease. Finally, all of the nAg-loaded gelatin hydrogels could inhibit the growth of the tested pathogens, which confirmed their applicability as antibacterial wound dressings.


Subject(s)
Anti-Bacterial Agents/chemistry , Bandages , Drug Carriers/chemistry , Gelatin/chemistry , Hydrogels/chemistry , Anti-Infective Agents, Local/chemistry , Biocompatible Materials/chemistry , Buffers , Humans , Materials Testing , Metal Nanoparticles/chemistry , Microbial Sensitivity Tests , Particle Size , Silver Nitrate/chemistry , Stress, Mechanical
17.
Taiwan J Obstet Gynecol ; 47(3): 296-9, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18935992

ABSTRACT

OBJECTIVE: The urine pregnancy test is an easily available diagnostic test in the present day and is routinely performed. The test is based on an immunochromatography technique. Here, we used an advanced nanomedicine technique for modification of the urine pregnancy test. MATERIALS AND METHODS: The preparation of gold nanoparticle solution in this study followed the standard method. We performed an experiment on both pregnancy-positive and -negative urine samples. First, a mixture with an equal amount (500 microliters) of gold nanoparticle solution and urine sample was prepared. Then, it was further tested for pregnancy by the urine pregnancy test strip. RESULTS: The pregnancy-positive mixture became pink, while the pregnancy-negative mixture became gray. The urine pregnancy test strip for a positive mixture had two lines, while the negative mixture had one line. CONCLUSION: This application can help the diagnosis of pregnancy and can be an alternative method for a urine pregnancy test. To our knowledge, this is the first report on this application.


Subject(s)
Gold , Metal Nanoparticles , Pregnancy Tests/methods , Urine/chemistry , Adolescent , Adult , Female , Humans , Pregnancy , Reference Values , Sampling Studies , Sensitivity and Specificity , Thailand , Urinalysis , Young Adult
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