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1.
BMC Genomics ; 25(1): 693, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39009981

ABSTRACT

ARs plays a crucial role in plant morphogenesis and development. The limited and inefficient rooting of scions poses a significant challenge to the efficiency and quality of clonal propagation of forest trees in silvicultural practices. Building on previous research conducted by our team, we found that applying IBA at a concentration of 1000 mg/L significantly enhanced mulberry rooting. This study aims to uncover the molecular mechanisms underlying this effect by analyzing RNA sequencing data from mulberry phloem before and after treatment with IBA over time intervals of 10, 20, 30, and 40 days. We identified 5226 DEGs, which were then classified into GO terms and KEGG pathways, showing significant enrichment in hormone signaling processes. Using WGCNA, we identified eight co-expression modules, two of which were significantly correlated with the IBA treatment. Additionally, 18 transcription factors that potentially facilitate ARs formation in mulberry were identified, and an exploratory analysis on the cis-regulatory elements associated with these transcription factors was conducted. The findings of this study provide a comprehensive understanding of the mechanisms of ARs in mulberry and offer theoretical support for the discovery and utilization of exceptional genetic resources within the species.


Subject(s)
Gene Expression Profiling , Gene Expression Regulation, Plant , Morus , Plant Roots , Transcription Factors , Morus/genetics , Morus/metabolism , Morus/growth & development , Plant Roots/genetics , Plant Roots/metabolism , Plant Roots/growth & development , Transcription Factors/metabolism , Transcription Factors/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , Transcriptome
2.
Sensors (Basel) ; 23(21)2023 Nov 03.
Article in English | MEDLINE | ID: mdl-37960653

ABSTRACT

Theoretical stability analysis is a significant approach to predicting chatter-free machining parameters. Accurate milling stability predictions highly depend on the dynamic properties of the process system. Therefore, variations in tool and workpiece attributes will require repeated and time-consuming experiments or simulations to update the tool tip dynamics and cutting force coefficients. Considering this problem, this paper proposes a transfer learning framework to efficiently predict the milling stabilities for different tool-workpiece assemblies through reducing the experiments or simulations. First, a source tool is selected to obtain the tool tip frequency response functions (FRFs) under different overhang lengths through impact tests and milling experiments on different workpiece materials conducted to identify the related cutting force coefficients. Then, theoretical milling stability analyses are developed to obtain sufficient source data to pre-train a multi-layer perceptron (MLP) for predicting the limiting axial cutting depth (aplim). For a new tool, the number of overhang lengths and workpiece materials are reduced to design and perform fewer experiments. Then, insufficient stability limits are predicted and further utilized to fine-tune the pre-trained MLP. Finally, a new regression model to predict the aplim values is obtained for target tool-workpiece assemblies. A detailed case study is developed on different tool-workpiece assemblies, and the experimental results validate that the proposed approach requires fewer training samples for obtaining an acceptable prediction accuracy compared with other previously proposed methods.

3.
Nanotechnology ; 33(37)2022 Jun 20.
Article in English | MEDLINE | ID: mdl-35653931

ABSTRACT

Highly ordered semiconducting single-walled carbon nanotubes(sc-SWCNTs) array with high purity, high linear density and controllable manner is strongly desired for carbon-based integrated circuits, yet it remains a big challenge. Herein, close-packed single layered and controllably aligned sc-SWCNTs arrays were obtained through dielectrophoresis using a high purity sc-SWCNT dispersion. Under optimized condition of length and average number of interconnecting junctions across the channel full of aligned sc-SWCNTs, field effect transistors (FETs) with high performance were achieved with both a high on/off current ratio and large carrier mobility. Based on the optimized channel length, by systematically optimizing the dielectrophoresis parameters of the frequency and duration of applied AC voltage (Vpp), the highly ordered sc-SWCNTs arrays with an ultra-high linear density of 54 ± 2 tubesµm-1showed relatively high device performance of FET. The fabrication process optimized in this report can be further extended and applied in large-area, low-cost carbon-based integrated circuits.

4.
Environ Res ; 212(Pt C): 113441, 2022 09.
Article in English | MEDLINE | ID: mdl-35561820

ABSTRACT

Hypochlorite pretreatment has been proven effective in enhancing waste activated sludge (WAS) anaerobic digestion performances recently. In this study, two semi-continuous anaerobic sequencing batch reactors (ASBRs), one fed with Ca(ClO)2 pretreated thickened WAS (TWAS) and one with raw TWAS, were operated at mesophilic conditions (35 °C) for 145 days. Three loading shocks were introduced to each reactor to compare the performance stability and resilience between the digestion of Ca(ClO)2 pretreated TWAS and untreated TWAS. Microbial community shifts were quantified to reveal the microbiome responses to disturbances. The results suggested that 1% Ca(ClO)2 enhanced the digestion of TWAS by inactivating and transforming the biomass to more easily digested substrates. Co-occurrence network analysis revealed that the strongest interactions in the microbial community occurred in the steady state of TWAS anaerobic digestion.


Subject(s)
Microbiota , Sewage , Anaerobiosis , Bioreactors , Calcium Compounds , Methane , Waste Disposal, Fluid/methods
5.
Angew Chem Int Ed Engl ; 61(38): e202205796, 2022 Sep 19.
Article in English | MEDLINE | ID: mdl-35639438

ABSTRACT

Porous organic polymer films (PFs) with intrinsical porosity and tuneable pore environment are ideally suited for application in electronic devices. However, the huge challenges still exist for construction of electronic devices based on PFs owing to lack of robustness, processability, and controllable preparation. Herein, we report the electrochemical preparation of carbazole-based porous organic polymer films (eCPFs) as switchable materials for the memristors. These eCPFs possess the characteristics of controllable thickness/size, high stability, and excellent porosity. Carbazole and cyano groups are introduced into the eCPFs to constructing electron transfer systems. Thus, the memristors constructed based on these eCPFs exhibit excellent switching performance, reliability, and reproducibility. The electrochemically controllable preparation method of porous organic polymer membranes proposed in this paper provides a feasible idea for the developments of electronic devices.

6.
Eur Radiol ; 31(5): 3195-3206, 2021 May.
Article in English | MEDLINE | ID: mdl-33068187

ABSTRACT

OBJECTIVES: To evaluate carotid stiffening in participants without conventional cardiovascular risk factors (CVRFs) by using ultrafast pulse wave velocity (ufPWV). METHODS: The present study enrolled 517 participants without conventional CVRFs (CVRF-Free total population). Subjects in this population were defined as current non-smokers with untreated blood pressure < 140/90 mmHg, fasting blood glucose (FBG) < 7.0 mmol/L, total cholesterol (TC) < 6.2 mmol/L, low-density lipoprotein cholesterol < 4.1 mmol/L, and high-density lipoprotein cholesterol ≥ 1.0 mmol/L. Participants in the subgroup with optimal CVRFs (CVRF-Optimal subgroup; n = 188) were defined as having blood pressure < 120/80 mmHg, TC < 5.2 mmol/L, and FBG < 5.6 mmol/L. Clinical interviews, physical examinations, serum draw, carotid intima-media thickness (cIMT), and ufPWV were evaluated. Adjusted odds ratios (ORs) with 95% confidence intervals and ordinal logistic regression models were used. RESULTS: Carotid stiffening was present in 46.2-54.5% of CVRF-Free subjects. Age, male sex, and body mass index (BMI) were independently associated with carotid stiffening in both the CVRF-Free total population and CVRF-Optimal subgroup (OR for age = 1.10-1.11, OR for male sex = 2.65-7.19, OR for BMI = 1.34-1.62; p < 0.05). Carotid stiffening was associated with TC only in the CVRF-Free total population (OR for TC = 1.84; p = 0.034). CONCLUSIONS: Many CVRF-Free individuals have carotid stiffening. ufPWV for atherosclerotic stiffening aids the assessment of early atherogenesis and may further clarify the true status of healthy adults without CVRFs. KEY POINTS: • CVRF-Optimal individuals have a lower carotid stiffness than CVRF-Free populations. • ufPWV is a quantitative predictor for the early assessment of AS. • Absent major CVRFs cannot be considered low risk for carotid stiffening and atherosclerosis.


Subject(s)
Atherosclerosis , Carotid Intima-Media Thickness , Adult , Atherosclerosis/diagnostic imaging , Humans , Infant , Male , Pulse Wave Analysis , Risk Factors , Ultrasonography
7.
Nanotechnology ; 33(4)2021 Nov 05.
Article in English | MEDLINE | ID: mdl-34666325

ABSTRACT

Polyaniline, as a kind of conductive polymer with commercial application prospects, is still under researches in its synthesis and applications. In this work, polyaniline was fabricated on flexible substrates including carbon cloths and polyethylene naphthalate byin situelectropolymerization method. The synthesized flexible electrodes were characterized by scanning electron microscopy, High resolution transmission electron microscope, atomic force microscope, Fourier transform infrared, x-ray diffraction, and x-ray photoelectron spectroscopy. Owing to the conductivity and the reversible redox property, the polyaniline/carbon cloth electrodes show excellent properties such as decent supercapacitor performance and good detection capability toward ascorbic acid. As supercapacitors, the electrodes exhibit a specific capacitance as high as 776 F g-1at a current density of 1 A g-1and a long cycle life of 20 000 times in the three-electrode system. As ascorbic acid sensors, the flexible electrodes demonstrate stable response to ascorbic acid in the range of 1-3000µM with an outstanding sensitivity (4228µA mM-1cm-2), low detection limit (1µM), and a fast response time. This work holds promise for high-performance and low-cost flexible electrodes for both supercapacitors and non-enzymatic ascorbic acid sensors, and may inspire inventions of self-powered electrochemical sensor.

8.
Anal Bioanal Chem ; 413(5): 1485-1492, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33462660

ABSTRACT

In this work, an ultrasensitive sensing system based on fluorescent carbon dots (CDs) was developed for the tartrazine (Tar) determination. The CDs were prepared via a simple one-pot hydrothermal method with m-phenylenediamine as the only precursor. The physical and chemical properties were in detail characterized by transmission electron microscopy (TEM), MALDI-TOF MS, UV-vis absorption and photoluminescence (PL) spectroscopy, elemental analysis, and Fourier transform infrared spectroscopy (FTIR). Upon exposure to Tar, the fluorescence of CDs was efficiently quenched via the dynamic interaction between CDs and Tar as well as the inner filter effect (IFE). With this information, the CDs were proposed as a fluorescence probe for Tar detection. It was found that CDs had high sensitivity and selectivity for Tar sensing, and the linear relationship was observed in the range of 0.01-25.0 µM with the corresponding detection limit (3σ/k) of 12.4 nM, which is much more sensitive than any of the existed CD-based sensing platform. The investigated sensing system was finally utilized for Tar sensing in various food matrices with a high degree of accuracy. The spiked recoveries were in a range of 96.4-105.2%, and the relative standard deviations (RSDs) were lower than 4.13%. This work highlights the great application prospects of CDs for Tar sensing in a rapid, simple, and sensitive way.


Subject(s)
Carbon/chemistry , Food Analysis/methods , Food Coloring Agents/analysis , Nanoparticles/chemistry , Tartrazine/analysis , Fluorescent Dyes/chemistry , Limit of Detection , Nanoparticles/ultrastructure , Spectrometry, Fluorescence/methods
9.
J Environ Manage ; 296: 113370, 2021 Oct 15.
Article in English | MEDLINE | ID: mdl-34351289

ABSTRACT

Herein we proposed an ecology model, based on a non-steady-state mass balance (16S rRNA MiSeq reads normalized by volatile suspended solids), to quantify microbiome responses to disturbances in wastewater bioreactors. Rather than focusing on the most abundant microbial groups commonly used in the literature, the goal of the model was to identify active species within the community. The model incorporated the temporal changes of operational taxonomic units following a disturbance, through considering the density and type of genotypes in the influent entering the bioreactor, in the effluent leaving the bioreactor, growing in the bioreactor, and in the waste sludge discharged from the bioreactor continuously or instantaneously, as well as the prior microbial community and the sludge characteristics. One application of this model demonstrated that significant differences existed between the key populations responding to an increasing organic loading rate and the dominant species in a high-rate thermophilic upflow anaerobic sludge blanket reactor.


Subject(s)
Microbiota , Wastewater , Anaerobiosis , Bioreactors , Microbiota/genetics , RNA, Ribosomal, 16S/genetics , Sewage , Waste Disposal, Fluid
10.
Molecules ; 26(21)2021 Oct 28.
Article in English | MEDLINE | ID: mdl-34770932

ABSTRACT

Surface-enhanced Raman scattering (SERS) has been widely reported to improve the sensitivity of Raman spectra. Ordinarily, the laser is focused on the sample to measure the Raman spectrum. The size of the focused light spot is comparable with that of micro-nano structures, and the number of micro-nano structures contained in the light spot area (defined as duty cycle) will severely affect the spectrum intensity. In this study, flower-like silver nanostructures were fabricated with a soft lyotropic liquid crystal template in order to investigate the effect of duty cycle. They were observed under a scanning electron microscope, and their spectrum enhancement factor was computed with the obtained Raman spectrum. Then, their duty cycles were measured using a SERS substrate at different locations. A formula was derived to represent the relation between the duty cycle of the nanoflowers and the Raman spectral intensity. This work could promote the actual applications of SERS in high-sensitivity spectrum testing.

11.
Zhongguo Zhong Yao Za Zhi ; 46(21): 5568-5575, 2021 Nov.
Article in Zh | MEDLINE | ID: mdl-34951208

ABSTRACT

Neutrophil extracellular traps(NETs) are networks of extracellular fibers primarily composed of DNA, histones, granular proteins, and cytoplasmic proteins and released to the outside of cells by neutrophils under the stimulation of bacteria, fungi, viruses, parasites, etc. NETs are generated in two forms, suicidal NETs and vital NETs, according to different stimuli. NETs have both anti-inflammatory and pro-inflammatory effects. On the one hand, they can play the anti-microbial role to resist inflammation by capturing, fixing, and killing invading pathogens, which is a special way for neutrophils to exert host defenses. On the other hand, in case of excessive formation or insufficient elimination, they can cause tissue damage directly, and also promote the release of inflammatory factors by recruiting other pro-inflammatory cells or proteins to further expand the inflammatory response, which is related to the pathologies of many diseases. In autoimmune diseases, NETs as important sources of autoantigens, can act as danger-associated molecular patterns( DAMPs) and activate the nucleotide-binding oligomerization domain leucine-rich repeats containing pyrin domain 3(NLRP3) inflammasome and complement system, thereby breaking self-tolerance and accelerating autoimmune inflammation. In addition, NETs can also activate other immune cells(such as B cells, antigen-presenting cells, and T cells) and regulate the acquired immune response. The present study reviewed the correlation of NETs with diseases such as systemic lupus erythematosus(SLE), rheumatoid arthritis(RA), and gouty arthritis(GA) to reveal the effect of dynamic balance between formation and clearance of NETs in autoimmune diseases and provide a theoretical basis for the investigation of underlying mechanisms and targeted therapies of traditional Chinese medicine.


Subject(s)
Arthritis, Rheumatoid , Autoimmune Diseases , Extracellular Traps , Lupus Erythematosus, Systemic , Humans , Neutrophils
12.
J Cell Physiol ; 234(9): 15686-15697, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30697739

ABSTRACT

Enterovirus 71 (EV71) is a small, nonenveloped icosahedral RNA virus and is the predominant causative pathogen of hand-foot-and-mouth disease. Recently, microRNAs (miRNAs) are reported to play important roles in the pathogenesis of EV71 replication. This study investigated the role of miR-545 in the EV71 replication and explored the underlying molecular mechanisms. We showed that miR-545 was upregulated in the EV71-infected human embryonic kidney (HEK) 293 cells and rhabdomyosarcoma (RD) cells. Overexpression of miR-545 promoted the viral replication of EV71 and attenuated the inhibitory effects of EV71 on cell viability in HEK293 and RD cells; while knockdown of miR-545 significantly suppressed the EV71 replication in these two cell lines. Bioinformatics analysis and luciferase reporter assay showed that miR-545 directly targeted the 3'untranslated region of phosphatase and tensin homolog (PTEN) and tumor necrosis factor receptor-associated factor 6 (TRAF6) in HEK293 cells. Furthermore, miR-545 negatively regulated the messenger RNA (mRNA) and protein expression of PTEN and TRAF6. The mRNA and protein expression of PTEN and TRAF6 was also suppressed by EV71 infection, which was attenuated by miR-545 knockdown in HEK293 cells. Overexpression of PTEN and TRAF6 both suppressed the EV71 replication in HKE293 cells, and also attenuated the enhanced effects of miR-545 overexpression on the EV71 replication in HEK293 cells. Collectively, our study for the first time showed that miR-545 had an enhanced effect on the EV71 replication in HEK293 and RD cells. Further mechanistic results indicated that miR-545 promoted EV71 replication at least partly via targeting PTEN and TRAF6.

13.
Water Environ Res ; 90(10): 1576-1596, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-30126493

ABSTRACT

Literature published in 2017 related to water reclamation and reuse is reviewed in four categories: sustainable reuse, treatment technology, implementation, and assessment and management. The development and improvement of conventional treatments and new methods that afford safe wastewater reuse are examined.


Subject(s)
Recycling/methods , Water , Conservation of Natural Resources , Water/chemistry , Water Purification
14.
Zhongguo Zhong Yao Za Zhi ; 42(8): 1545-1550, 2017 Apr.
Article in Zh | MEDLINE | ID: mdl-29071860

ABSTRACT

One of the top-level researches of biopharmaceutics classification system of Chinese materia medica (CMMBCS) is the study on single component in compound Chinese medicine. The medicines shall be classified according to its solubility and intestinal permeability, as well as the ascending degree in multicomponent environment. Based on above, we chose berberine as the main object to explore the change rules of its solubility and intestinal permeability in Gegen Qinlian decoction. Shaking flask-HPLC was used to detect the solubility changes of berberine in compounds. The qualitative investigation of berberine in intestinal absorption was measured by everted gut sac, and the quantitative research of berberine in intestinal absorption was measured by single-pass intestinal perfusion experiment, while the qualitative and quantitative research of berberine absorption into blood was measured by in intestinal perfusion with venous sampling experiment.


Subject(s)
Berberine/pharmacokinetics , Biopharmaceutics/classification , Animals , Berberine/chemistry , Chromatography, High Pressure Liquid , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacokinetics , Intestinal Absorption
16.
Zhongguo Zhong Yao Za Zhi ; 41(7): 1183-1187, 2016 Apr.
Article in Zh | MEDLINE | ID: mdl-28879728

ABSTRACT

In the study of biopharmaceutics classification system of Chinese materia medica (CMMBCS), the interactions of multiple components in the absorption should be taken into consideration in simultaneous multi-component determination. To investigate the absorption of multiple components, the in vitro everted gut sac model was used in this study, wtih lotus leaves as the research object. Aquantitative analysis was also carried out for the known components in this study. Totally 19 components in lotus extracts were absorbed by the intestinal tract, the Papp levels of the known components were nuciferine (1×10⁻5-1×10⁻6 cm•s⁻¹), rutin (1×10⁻6-1×10⁻7 cm•s⁻¹), hyperoside (1×10⁻6 cm•s⁻¹), isoquercitrin (1×10⁻6-1×10⁻7 cm•s⁻¹) and astragalin (1×10⁻6-1×10⁻7 cm•s⁻¹), respectively. These components showed a low permeability under a multi-component environment. This study was carried out to lay a foundation for further relevant target studies for different categories of components.


Subject(s)
Drugs, Chinese Herbal/pharmacokinetics , Intestinal Absorption , Intestines/drug effects , Lotus/chemistry , Biopharmaceutics , Permeability , Plant Leaves/chemistry
17.
Luminescence ; 30(2): 131-6, 2015 Mar.
Article in English | MEDLINE | ID: mdl-24891100

ABSTRACT

Twelve lanthanide complexes with cinnamate (cin(-) ) and 1,10-phenanthroline (phen) were synthesized and characterized. Their compositions were assumed to be RE(cin)3 phen (RE(3+) = La(3+) , Pr(3+) , Nd(3+) , Sm(3+) , Eu(3+) , Gd(3+) , Tb(3+) , Dy(3+) , Ho(3+) , Tm(3+) , Yb(3+) , Lu(3+) ). The interaction mode between the complexes and DNA was investigated by fluorescence quenching experiment. The results indicated the complexes could bind to DNA and the main binding mode is intercalative binding. The fluorescence quenching constants of the complexes increased from La(cin)3 phen to Lu(cin)3 phen. Additionally, the antibacterial activity testing showed that the complexes exhibited excellent antibacterial ability against Escherichia coli, and the changes of antibacterial ability are in agreement with that of the fluorescence quenching constants.


Subject(s)
Anti-Bacterial Agents/pharmacology , Cinnamates/pharmacology , DNA/chemistry , Escherichia coli/drug effects , Fluorescence , Lanthanoid Series Elements/pharmacology , Organometallic Compounds/pharmacology , Phenanthrolines/pharmacology , Animals , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Cattle , Cinnamates/chemistry , Dose-Response Relationship, Drug , Lanthanoid Series Elements/chemistry , Microbial Sensitivity Tests , Organometallic Compounds/chemical synthesis , Organometallic Compounds/chemistry , Phenanthrolines/chemistry , Spectrometry, Fluorescence , Structure-Activity Relationship
18.
Sci Total Environ ; 925: 171431, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38442755

ABSTRACT

This study addresses the pressing environmental concerns associated with the rapidly growing distillery industry, which is a significant contributor to wastewater generation. By focusing on the treatment of distillery wastewater using anaerobic digestion, this research explores the potential to convert organic materials into biofuels (methane). Moreover, the study aims to recover both methane and phosphorus from distillery wastewater in a single anaerobic reactor, which represents a novel and unexplored approach. Laboratory-scale experiments were conducted using mesophilic and thermophilic upflow anaerobic sludge blanket reactors. A key aspect of the study involved the implementation of a unique strategy: the mixing of centrate and spent caustic wastewater streams. This approach was intended to enhance treatment performance, manipulate the microbial community structure, and thereby optimizing the overall treatment performance. The integration of the centrate and spent caustic streams yielded remarkable co-benefits, resulting in significant biomethane production and efficient phosphorus precipitation. The study demonstrated a phosphorus removal efficiency of ∼60 % throughout the 130-140 days operation period. The recovery of phosphorus via the reactor sludge offers exciting opportunities for its utilization as a fertilizer or as a raw material within the phosphorus refinery industry. The biomethane produced during the treatment exhibits significant energy potential, estimated at 0.5 GJ/(m3 distillery wastewater).


Subject(s)
Caustics , Wastewater , Sewage/chemistry , Waste Disposal, Fluid/methods , Anaerobiosis , Phosphorus , Biomineralization , Bioreactors , Methane
19.
Foods ; 13(8)2024 Apr 13.
Article in English | MEDLINE | ID: mdl-38672864

ABSTRACT

Sanghuangporus sanghuang is a rare fungus growing on mulberry trees that has immense medicinal value. This study aimed to optimize the liquid-fermentation-media formulation and culture conditions for large-scale culturing of S. sanghuang by performing one-way testing and response surface methodology. The antioxidant and anticancer activities of the extracellular polysaccharides from S. sanghuang were also analyzed. The optimal formulation and growth conditions for S. sanghuang were as follows: glucose, 30.2 ± 0.37 g/L; yeast extract, 14.60 ± 0.05 g/L; dandelion powder, 1.24 ± 0.01 g/L; shaker speed, 150 r/min; and temperature, 25 °C. We obtained 13.99 ± 0.42 g/L of mycelium biomass by culturing S. sanghuang for 15 days with the optimized formulation. This was 2-fold higher than the mycelial mass obtained with the sub-optimal formulation. The extracellular fungal polysaccharides showed significant antioxidant activity against ABTS and DPPH free radicals, and significantly reduced the in vitro growth and survival of several cancer cell lines. The anticancer activity of the extracellular fungal polysaccharides was significantly higher in the human glioma cells than in other cancer cell lines. In summary, this study optimized the liquid media formulation and conditions for the large-scale culturing of S. sanghuang. Furthermore, the extracellular polysaccharides from S. sanghuang showed significant antioxidant and anticancer activities.

20.
Pak J Pharm Sci ; 26(5): 929-37, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24035948

ABSTRACT

The present study was performed to optimize the formulation of metoprolol succinate (MS) sustained release tablets using hydroxypropyl methylcellulose (HPMC) and sodium alginate (SA) as the matrix combination. After investigating the effects of various parameters on drug release, a 2-factor, 5-level central composite design was employed, using the amount of HPMC K4M (A) and SA (318 cP) (B) as the independent variables and the drug percentage released at 1h, 4h, 8h, 20h (Q1, Q4, Q8, Q20) as the responses. Response surfaces were established to obtain the matrix ranges and the main factors affecting four responses. In order to validate the optimization study, six confirmatory runs were performed; indicating high predictability of response surface methodology for MS sustained release tablets. Data fitting to Peppas equation indicated that the mechanism of drug release could be diffusion along with erosion. This matrix combination can be used as a good alternative to the commercially pellet technology, which was complicated, time-consuming and energy-intensive.


Subject(s)
Adrenergic beta-Antagonists/chemistry , Metoprolol/analogs & derivatives , Technology, Pharmaceutical/methods , Alginates/chemistry , Chemistry, Pharmaceutical , Delayed-Action Preparations , Diffusion , Glucuronic Acid/chemistry , Hexuronic Acids/chemistry , Hypromellose Derivatives , Kinetics , Methylcellulose/analogs & derivatives , Methylcellulose/chemistry , Metoprolol/chemistry , Models, Chemical , Solubility , Tablets , Viscosity
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