Preparation and Sustained-Release Testing of Chitosan/Montmorillonite/Acetaminophen Microspheres

2013 ◽  
Vol 763 ◽  
pp. 112-116
Author(s):  
Hao Ran Zhou ◽  
Hao Jiang ◽  
Xiao Jiao Fang ◽  
Shuang Zhao ◽  
Cui Guo
Keyword(s):  
Sustained Release ◽  
Slow Release ◽  
Raw Materials ◽  
Orthogonal Experiment ◽  
Drug Loading ◽  
Poor Performance ◽  
Ft Ir ◽  
Release Testing ◽  
Uniform Particle Size ◽  
Crosslinking Agents

Chitosan (CS) is an important slow-release carrier of drugs and fertilizers. The pure chitosan have poor performance, it should be added to a certain amount of crosslinking agents, emulsifiers and porogenic agents to improve the performance of it. The advantage of montmorillonite is no pollution and no toxicity, composite material filled in montmorillonite has an excellent mechanical properties. In this article, CS/MMT/ACAP drug-loading microsperes was prepared with the CS, ACAP and MMT as the main raw materials by emulsification-crosslinking method. Orthogonal experiment was designed to optimize the preparation process of the CS/MMT/ACAP drug-loading microspheres. FT-IR, XRD and SEM were applied to characterize the structure and morphology of microspheres. The sustained release effect of CS/MMT/ACAP microsphere was measured by sustained release measurement. The results show that the CS/MMT/ACAP drug-loading micropheres were successfully prepared by emulsification-crosslinking method. The microspheres assumed a good sphericity and a uniform particle size distribution; the drug-loading microspheres had good sustained release effect.

The Preparation and Characteristics of Chitosan-Acetaminophen Drug-Loading Micropheres

2012 ◽  
Vol 586 ◽  
pp. 161-165 ◽  
Author(s):  
Hao Ran Zhou ◽  
Jing Yu Zhang ◽  
Hao Jiang
Keyword(s):  
Particle Size ◽  
Sustained Release ◽  
Raw Materials ◽  
Orthogonal Experiment ◽  
Drug Loading ◽  
Average Particle Size ◽  
Average Particle ◽  
Preparation Process ◽  
Structure And Morphology ◽  
Ft Ir

CS-ACAP drug-loading microsperes are prepared with using CS and ACAP as the main raw materials by emulsification-crosslinking method. Orthogonal experiment was designed to optimize the preparation process of the CS-ACAP drug-loading microspheres. FT-IR and SEM were applied to characterize the structure and morphology of microspheres. The sustained release effect of CS-ACAP microsphere was measured by sustained release measurement. The results showed that the CS-ACAP drug-loading micropheres were successfully prepared by emulsification-crosslinking method. Obtained microspheres as a perforated sphere, the average particle size of the microspheres was 30μm and the microspheres had a uniformly particle size distribution; the drug-loaded microspheres had good sustained release effect.

scholarly journals Polyurethane Composite Foams Synthesized Using Bio-Polyols and Cellulose Filler

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3474
Author(s):  
Katarzyna Uram ◽  
Milena Leszczyńska ◽  
Aleksander Prociak ◽  
Anna Czajka ◽  
Michał Gloc ◽  
...  
Keyword(s):  
Cross Sections ◽  
Raw Materials ◽  
Polyurethane Foams ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Polyurethane Composite ◽  
Composite Foams ◽  
Closed Cell ◽  
Ft Ir ◽  
The Fourier Transform

Rigid polyurethane foams were obtained using two types of renewable raw materials: bio-polyols and a cellulose filler (ARBOCEL® P 4000 X, JRS Rettenmaier, Rosenberg, Germany). A polyurethane system containing 40 wt.% of rapeseed oil-based polyols was modified with the cellulose filler in amounts of 1, 2, and 3 php (per hundred polyols). The cellulose was incorporated into the polyol premix as filler dispersion in a petrochemical polyol made using calenders. The cellulose filler was examined in terms of the degree of crystallinity using the powder X-ray diffraction PXRD -and the presence of bonds by means of the fourier transform infrared spectroscopy FT-IR. It was found that the addition of the cellulose filler increased the number of cells in the foams in both cross-sections—parallel and perpendicular to the direction of the foam growth—while reducing the sizes of those cells. Additionally, the foams had closed cell contents of more than 90% and initial thermal conductivity coefficients of 24.8 mW/m∙K. The insulation materials were dimensionally stable, especially at temperatures close to 0 °C, which qualifies them for use as insulation at low temperatures.

Preparation, evaluation, and in vitro release of chitosan-alginate tanshinone self-microemulsifying sustained-release microcapsules

2020 ◽  
pp. 1-9
Author(s):  
Yunhong Wang ◽  
Rong Hu ◽  
Yanlei Guo ◽  
Weihan Qin ◽  
Xiaomei Zhang ◽  
...  
Keyword(s):  
Drug Release ◽  
Sustained Release ◽  
Release Rate ◽  
Orthogonal Design ◽  
Drug Loading ◽  
In Vitro Release ◽  
Core Material ◽  
Evaluation Indexes ◽  
Vitro Release

OBJECTIVE: In this study we explore the method to prepare tanshinone self-microemulsifying sustained-release microcapsules using tanshinone self-microemulsion as the core material, and chitosan and alginate as capsule materials. METHODS: The optimal preparation technology of chitosan-alginate tanshinone self-microemulsifying sustained-release microcapsules was determined by using the orthogonal design experiment and single-factor analysis. The drug loading and entrapment rate were used as evaluation indexes to assess the quality of the drug, and the in vitro release rate was used to evaluate the drug release performance. RESULTS: The best technology of chitosan-alginate tanshinone self-microemulsifying sustained-release microcapsules is as follows: the concentration of alginate is 1.5%, the ratio of tanshinone self-microemulsion volume to alginate volume to chitosan mass is 1:1:0.5 (ml: ml: g), and the best concentration of calcium chloride is 2.0%. To prepare the microcapsules using this technology, the drug loading will be 0.046%, the entrapment rate will be 80.23%, and the 24-hour in vitro cumulative release rate will be 97.4%. CONCLUSION: The release of the microcapsules conforms to the Higuchi equation and the first-order drug release model and has a good sustained-release performance.

scholarly journals Development of In Situ Self-Assembly Nanoparticles to Encapsulate Lopinavir and Ritonavir for Long-Acting Subcutaneous Injection

Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 904
Author(s):  
Irin Tanaudommongkon ◽  
Asama Tanaudommongkon ◽  
Xiaowei Dong
Keyword(s):  
Sustained Release ◽  
Trough Concentration ◽  
Self Assembly ◽  
Subcutaneous Injection ◽  
Drug Loading ◽  
Entrapment Efficiency ◽  
Long Acting

Most antiretroviral medications for human immunodeficiency virus treatment and prevention require high levels of patient adherence, such that medications need to be administered daily without missing doses. Here, a long-acting subcutaneous injection of lopinavir (LPV) in combination with ritonavir (RTV) using in situ self-assembly nanoparticles (ISNPs) was developed to potentially overcome adherence barriers. The ISNP approach can improve the pharmacokinetic profiles of the drugs. The ISNPs were characterized in terms of particle size, drug entrapment efficiency, drug loading, in vitro release study, and in vivo pharmacokinetic study. LPV/RTV ISNPs were 167.8 nm in size, with a polydispersity index of less than 0.35. The entrapment efficiency was over 98% for both LPV and RTV, with drug loadings of 25% LPV and 6.3% RTV. A slow release rate of LPV was observed at about 20% on day 5, followed by a sustained release beyond 14 days. RTV released faster than LPV in the first 5 days and slower than LPV thereafter. LPV trough concentration remained above 160 ng/mL and RTV trough concentration was above 50 ng/mL after 6 days with one subcutaneous injection. Overall, the ISNP-based LPV/RTV injection showed sustained release profiles in both in vitro and in vivo studies.

scholarly journals A Methodology Based on FT-IR Data Combined with Random Forest Model to Generate Spectralprints for the Characterization of High-Quality Vinegars

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1411
Author(s):  
José Luis P. Calle ◽  
Marta Ferreiro-González ◽  
Ana Ruiz-Rodríguez ◽  
Gerardo F. Barbero ◽  
José Á. Álvarez ◽  
...  
Keyword(s):  
Random Forest ◽  
Raw Materials ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Raw Material ◽  
Support Vector ◽  
Protected Designation Of Origin ◽  
Ft Ir

Sherry wine vinegar is a Spanish gourmet product under Protected Designation of Origin (PDO). Before a vinegar can be labeled as Sherry vinegar, the product must meet certain requirements as established by its PDO, which, in this case, means that it has been produced following the traditional solera and criadera ageing system. The quality of the vinegar is determined by many factors such as the raw material, the acetification process or the aging system. For this reason, mainly producers, but also consumers, would benefit from the employment of effective analytical tools that allow precisely determining the origin and quality of vinegar. In the present study, a total of 48 Sherry vinegar samples manufactured from three different starting wines (Palomino Fino, Moscatel, and Pedro Ximénez wine) were analyzed by Fourier-transform infrared (FT-IR) spectroscopy. The spectroscopic data were combined with unsupervised exploratory techniques such as hierarchical cluster analysis (HCA) and principal component analysis (PCA), as well as other nonparametric supervised techniques, namely, support vector machine (SVM) and random forest (RF), for the characterization of the samples. The HCA and PCA results present a clear grouping trend of the vinegar samples according to their raw materials. SVM in combination with leave-one-out cross-validation (LOOCV) successfully classified 100% of the samples, according to the type of wine used for their production. The RF method allowed selecting the most important variables to develop the characteristic fingerprint (“spectralprint”) of the vinegar samples according to their starting wine. Furthermore, the RF model reached 100% accuracy for both LOOCV and out-of-bag (OOB) sets.

Study on Modified Rapeseed Oil/Montmorillonite Nanocomposites

2010 ◽  
Vol 123-125 ◽  
pp. 1291-1294 ◽  
Author(s):  
Bin Lü ◽  
Jian Zhong Ma ◽  
Dang Ge Gao ◽  
Lei Hong
Keyword(s):  
Rapeseed Oil ◽  
Fourier Transforms ◽  
Raw Materials ◽  
Infrared Spectrometry ◽  
Emulsifying Properties ◽  
X Ray Diffraction ◽  
Layer Spacing ◽  
Transmission Electron ◽  
Ft Ir ◽  
Better Than

Modified rapeseed oil(MRO) was prepared by using rapeseed oil, ethylene diamine and acrylic acid as the raw materials. Modified rapeseed oil/montmorillonite(MRO/MMT) nanocomposite was prepared by using modified rapeseed oil and montmorillonite. The emulsifying properties of MRO and MRO/MMT were determined respectively. Fourier transforms infrared spectrometry (FT-IR) and Transmission Electron microscope (TEM) results showed that MRO/MMT was prepared successfully. X-ray diffraction (XRD) results showed that modified rapeseed oil could smoothly enter the interlayer of montmorillonite, and modified the montmorillonite; with an increase in the amount of montmorillonite, the layer spacing of montmorillonite in the MRO/MMT lower after the first increase. The results of emulsifying properties indicated that emulsifying properties of MRO/MMT was better than MRO.

Preparation and Photocatalytic Activity of Cu/BiVO4 by Solid State Grinding Method for Degradation of Methyl Orange

2016 ◽  
Vol 703 ◽  
pp. 321-325
Author(s):  
Hai Feng Chen ◽  
Jia Mei Chen ◽  
Zhi Xue Pan
Keyword(s):  
Methyl Orange ◽  
Solid State ◽  
Visible Light ◽  
Raw Materials ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
Illumination Time ◽  
Grinding Method ◽  
Ft Ir ◽  
Degradation Of Methyl Orange

In this work, novel Cu/BiVO4 photocatalyst were prepared by a low-temperature solid state grinding method using Bi (NO3)3•5H2O, NH4VO3 and Cu (NO3)2•2H2O as raw materials. The structure and properties of the samples were characterized by Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD) and UV-vis diffused reflectance spectroscopy (DRS); Using the degradation of methyl orange (MO) as the probe, it was simulated as the degradation of sewage under the visible light to study the influence of the illumination time and the amount of photocatalysts. Compared with the pure BiVO4, the visible-light absorption scope of BiVO4 was broadened by doping Cu, the UV-Visible absorption edges were slightly red shift and the band gap was narrower. Comparatively speaking, the results indicted that the doped Cu enhanced the photocatalytic activities of BiVO4.

Gemcitabine Nanoparticles Improve the Activity of Ovarian Cancer Cells by Inhibiting CA-125 and Apoptosis-Related Proteins

2021 ◽  
Vol 11 (7) ◽  
pp. 1400-1405
Author(s):  
Sisi Yi ◽  
Chen Feng ◽  
Xiaohua Hu
Keyword(s):  
Ovarian Cancer ◽  
Cell Viability ◽  
Release Rate ◽  
Inhibitory Action ◽  
Encapsulation Efficiency ◽  
Slow Release ◽  
Drug Loading ◽  
Ca 125 ◽  
Ovarian Cancer Cells ◽  
Related Proteins

In recent years, the risk of ovarian cancer (OC) has become increasingly prevalent. Gemcitabine (GE) provides excellent inhibitory action on some solid tumors, but how it affects OC remains elusive. In the present research, we prepared GE nanoparticles (GEN) and analyzed OC cell viability under its intervention, hoping to conceive novel ideas for future clinical treatment of OC. Through experiments, we observed that the encapsulation efficiency and drug loading of GEN were observably higher than those of GE alone, and the release rate presented a stable slow release state. Under GEN intervention, the viability of OC cells was decreased, the apoptosis rate was elevated, and the apoptosis-related proteins were activated, while CA-125 was suppressed. Therefore, we can see that GEN exert favorable inhibitory action on OC cell viability, whose mechanism may be achieved through activating apoptosis-related proteins and inhibiting CA-125, which may be a new scheme for OC treatment in the future.

Multivesicular liposome: A lipid-based drug delivery system for efficient drug delivery

2021 ◽  
Vol 27 ◽  
Author(s):  
Bapi Gorain ◽  
Bandar E. Al-Dhubiab ◽  
Anroop Nair ◽  
Prashant Kesharwani ◽  
Manisha Pandey ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Sustained Release ◽  
Delivery System ◽  
Targeted Delivery ◽  
Drug Loading ◽  
Therapeutic Agents ◽  
Laboratory Research ◽  
Efficacy And Safety ◽  
Liposomal Delivery ◽  
Proteins And Peptides

: The advancement of delivery tools for therapeutic agents has brought several novel formulations with increased drug loading, sustained release, targeted delivery, and prolonged efficacy. Amongst the several novel delivery approaches, multivesicular liposome has gained potential interest because this delivery system possesses the above advantages. In addition, this multivesicular liposomal delivery prevents degradation of the entrapped drug within the physiological environment while administered. The special structure of the vesicles allowed successful entrapment of hydrophobic and hydrophilic therapeutic agents, including proteins and peptides. Furthermore, this novel formulation could maintain the desired drug concentration in the plasma for a prolonged period, which helps to reduce the dosing frequencies, improve bioavailability, and safety. This tool could also provide stability of the formulation, and finally gaining patient compliance. Several multivesicular liposomes received approval for clinical research, while others are at different stages of laboratory research. In this review, we have focused on the preparation of multivesicular liposomes along with their application in different ailments for the improvement of the performance of the entrapped drug. Moreover, the challenges of delivering multivesicular vesicles have also been emphasized. Overall, it could be inferred that multivesicular liposomal delivery is a novel platform of advanced drug delivery with improved efficacy and safety.

scholarly journals Structures and Properties of Self - crosslinking Silicone Resin

2018 ◽  
Vol 38 ◽  
pp. 02019
Author(s):  
Yong-xin Zhao ◽  
Ying-qiang Zhang
Keyword(s):  
Thermal Decomposition ◽  
Raw Materials ◽  
Decomposition Temperature ◽  
Light Transmittance ◽  
Silicone Resin ◽  
Structures And Properties ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Good Heat Resistance ◽  
Good Heat

Highly transparent silicone resin with self-crosslinking structure was prepared using phenyltrimethoxysilane, diphenyldimethoxysilane, 1,3,5,7-cyclotetra(methyl siloxane) and bisvinyltetramethyldisiloxane as main raw materials. The structure of silicone resin was determined by Fourier Transform Infrared Spectroscopy (FT-IR). The light transmittance was measured by UV-Vis spectroscopy. Thermogravimetric analysis (TGA) was used to study the thermal decomposition process. The microstructure of cured self-crosslinking silicone resin is more uniform, resulting in better light transmittance up to 100% in the range of 400nm ~ 800nm. The cured has relatively good heat resistance, the initial thermal decomposition temperature of the cured could be up to 315.8 °C. SEM observations show that the self-crosslinking silicone has a uniform, textured structure, higher transparency compared with the existing condensation silicone material, and can be used as advanced architectural translucent materials and optics packaging materials.

Sign in / Sign up

Export Citation Format

Share Document