Modification of Coconut-Shell Activated Carbon and its Controlled Release Property for Nicotinic Acid

2010 ◽  
Vol 160-162 ◽  
pp. 1239-1244
Author(s):  
Wei Lu ◽  
Zheng Yuan Hong ◽  
Jun Xia Yu ◽  
Jia Guo
Keyword(s):  
Controlled Release ◽  
Nicotinic Acid ◽  
Activated Carbons ◽  
Gastric Fluid ◽  
Coconut Shell ◽  
High Yield ◽  
Simulated Gastric Fluid ◽  
Adsorptive Capacity ◽  
Simulated Intestinal Fluid ◽  
Coconut Shell Activated Carbon

In this paper, coconut-shell activated carbons (CSAC) used as the carrier of nicotinic acid (VPP) and the process of controlled release of VPP were studied. CSACs with relatively high yield and good adsorptive capacity prepared by CO2 activation method under the condition of 850oC, 1.5h activation time and 1.5L/min CO2 flow rate, were used as the VPP carrier. Langmuir model was suitable for describing the process of CSAC adsorbing VPP, and the maximum adsorptive capacity of CSAC was 136.32mg/g. The cumulative release percentages of VPP in distilled water, simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) were 22.53%, 45.86% and 53.94%, respectively. Higuchi model was the most suitable for describing the processes of CSAC releasing of VPP in the different media.

Vitamin B3 Adsorbed onto Activated Carbons and their Release Kinetics in Different Media

2011 ◽  
Vol 233-235 ◽  
pp. 697-700
Author(s):  
Xia Yang ◽  
Tao Zhang ◽  
Yao Ding ◽  
Jun Bo Li ◽  
Jia Guo
Keyword(s):  
Activated Carbon ◽  
Activated Carbons ◽  
Release Kinetics ◽  
Gastric Fluid ◽  
Simulated Gastric Fluid ◽  
Adsorptive Capacity ◽  
Vitamin B ◽  
Simulated Intestinal Fluid ◽  
Mathematical Simulations ◽  
Release Processes

The adsorption of vitamin B3 (VPP) by activated carbons and their release processes in the distilled water, simulated gastric fluid and simulated intestinal fluid were investigated. The adsorptive capacity of the activated carbon for VPP was 94.91 mg/g. Simulated gastric fluid could promote the release of VPP adsorbed by the activated carbon, and the cumulative percentage of VPP released was 76.36%. Based on three commonly-used kinetic models for drug release, mathematical simulations were carried out. It was found that the release processes of VPP in three different media could be fitted well by the Higuchi model Q = kt1/2 + C.

FABRICATION OF CURCUMIN LOADED GUAR GUM MICROPARTICLES FOR CONTROLLED RELEASE BY EMULSION GELATION TECHNIQUE

INDIAN DRUGS ◽  
2017 ◽  
Vol 54 (02) ◽  
pp. 69-72
Author(s):  
G Roopa ◽  
◽  
C. Jayanthi ◽  
R Karki ◽  
H. Joshi ◽  
...  
Keyword(s):  
Particle Size ◽  
Controlled Release ◽  
Guar Gum ◽  
Drug Loading ◽  
Surface Characteristics ◽  
Gastric Fluid ◽  
Simulated Gastric Fluid ◽  
Simulated Intestinal Fluid ◽  
Dsc Studies

Cross-linked guar gum microparticles of curcumin were prepared for controlled release by emulsion gelation method using glutaraldehyde as cross-linking agent. Morphology and surface characteristics of the formulations were assessed by scanning electron microscopy. Particle size of the guar gum microparticles was determined by optical microscopy. The mean particle size ranged from 82 to 250 μ. The % drug loading was found to be in the range of 20 to 51% while the percentage encapsulation efficiency was ranging between 29 to 86%. FT-IR and DSC studies revealed the compatibility of the drug with the polymer. Formulation CGMP3 exhibited maximum % EE of 84%, In vitro drug-release studies were performed in simulated gastric fluid (without enzymes) for 2 h followed by simulated intestinal fluid (without enzymes) for 6 h and continued for 24 h. Formulation CGMP3 exhibited relatively more sustained release profile than the other formulations. All formulations of 1.5% guar gum (CGMP2, CGMP3 and CGMP4) have shown retarded release than 1.0 % guar gum formulations (CGMP6, CGMP7 and CGMP8). Optimal glutaraldehyde concentration was found to be 2%. The optimized formulation subjected to stability studies was found to be stable when observed for particle size and drug content.

scholarly journals Fabrication of Multi-Layered Microspheres Based on Phase Separation for Drug Delivery

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 723
Author(s):  
He Xia ◽  
Ang Li ◽  
Jia Man ◽  
Jianyong Li ◽  
Jianfeng Li
Keyword(s):  
Aqueous Solution ◽  
Phase Separation ◽  
Gastric Fluid ◽  
Simulated Gastric Fluid ◽  
Sustained Drug Release ◽  
Simulated Intestinal Fluid ◽  
Glycol Diacrylate ◽  
Emulsion Droplets ◽  
Collection Tube ◽  
Poly Ethylene

In this work, we used a co-flow microfluidic device with an injection and a collection tube to generate droplets with different layers due to phase separation. The phase separation system consisted of poly(ethylene glycol) diacrylate 700 (PEGDA 700), PEGDA 250, and sodium alginate aqueous solution. When the mixture droplets formed in the outer phase, PEGDA 700 in the droplets would transfer into the outer aqueous solution, while PEGDA 250 still stayed in the initial droplet, breaking the miscibility equilibrium of the mixture and triggering the phase separation. As the phase separation proceeded, new cores emerged in the droplets, gradually forming the second and third layers. Emulsion droplets with different layers were polymerized under ultraviolet (UV) irradiation at different stages of phase separation to obtain microspheres. Microspheres with different layers showed various release behaviors in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF). The release rate decreased with the increase in the number of layers, which showed a potential application in sustained drug release.

Preparation and Characterization of Cefradine/Montmorillionite Composites

2012 ◽  
Vol 560-561 ◽  
pp. 434-437 ◽  
Author(s):  
Lan Wang ◽  
Wen Ji Guo ◽  
Yan Zhao Zhao
Keyword(s):  
Gastric Fluid ◽  
Simulated Gastric Fluid ◽  
X Ray Diffraction ◽  
Simulated Intestinal Fluid ◽  
Solution Intercalation ◽  
Method Of Solution ◽  
Ft Ir ◽  
In The Beginning ◽  
Ft Ir Spectroscopy

The objective of this paper was to prepare the composite of crefradine/montmorillionite in the method of solution intercalation. The drug load and intercalation rate varied with the drug concentration. X-ray diffraction (XRD), Fourier transformed infrared (FT-IR) Spectroscopy, and thermal analysis (TG-DSC) were applied to characterize composite mentioned above. Together with drug release tests, results indicate cefradine intercalated into montmorillionite.The release profiles of cefradine/MMT in simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 7.4) at 37°Cduring 10h are shown in Fig. 4. The amount of cefradine in the beginning 2h came up to 35% and 50%, and in the following time, cefradine released slowly. The release behaviors met the requirements of sustained release.

scholarly journals THE USE OF CLINOPTILOLITES AS CARRIER OF METFORMIN HYDROCHLORIDE IN DRUG DELIVERY SYSTEM: IN VITRO DRUG RELEASE STUDY

2018 ◽  
Vol 11 (11) ◽  
pp. 285
Author(s):  
Putra Imwa ◽  
Kusumawati Igaw
Keyword(s):  
Drug Release ◽  
Gastric Fluid ◽  
Simulated Gastric Fluid ◽  
Metformin Hydrochloride ◽  
Simulated Intestinal Fluid ◽  
In Vitro Drug Release ◽  
Encapsulation Process ◽  
N2 Sorption ◽  
Metformin Hcl

Objective: As an antidiabetic drug, metformin hydrochloride (HCl) has been well known to possess low oral bioavailability and short half-life. In this study, we prepared the drug delivery system (DDS) of metformin HCl and clinoptilolite as its carrier. The in vitro drug release profile was further investigated.Methods: DDS was made by encapsulating metformin HCl on clinoptilolite using the wet impregnation method at various pH and initial concentration of metformin HCl. Fourier transform infrared spectrometer (FTIR), X-ray diffractometer (XRD), and N2 Sorption Analyzer were used to characterize the as-synthesized DDS. Drug release study was conducted by stirring the DDS in simulated gastric fluid and simulated intestinal fluid over 12 h.Results: The encapsulation process was achieved optimally at pH 7.0 and initial concentration of metformin HCl of 300 mg/l (CLI2-300 denoted DDS). The results of FTIR and N2 sorption analyzer confirmed the existence of metformin HCl on clinoptilolites. Meanwhile, the XRD result showed that the crystallinity of clinoptilolites remained unchanged after the encapsulation process. The cumulative drug release in the simulated gastric fluid was found to be higher than that in the simulated intestinal fluid, which indicated the potent influence of pH on the release properties of the drugs. The drug release kinetics of metformin HCl from clinoptilolite was best fitted into the Korsmeyer-Peppas model with non-Fickian transport mechanism.Conclusion: We found that clinoptilolite was suitable for DDS application, particularly as a carrier of metformin HCl.

Experimental Study on Dynamic Adsorption of Xenon over Adsorbents

2013 ◽  
Vol 739 ◽  
pp. 142-147
Author(s):  
Guo Li He ◽  
Hong Hong Yi ◽  
Xiao Long Tang ◽  
Fen Rong Li ◽  
Yun Dong Li ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Activated Carbons ◽  
Coconut Shell ◽  
Dynamic Adsorption ◽  
13X Zeolite ◽  
Zeolite 13X ◽  
Xenon Adsorption ◽  
Zeolite 5A ◽  
5A Zeolite ◽  
Coconut Shell Activated Carbon

Selecting effective xenon adsorbents is important for preventing significant global nuclear proliferation. The adsorption capacity of coconut shell activated carbons (SAC),zeolite 10X,zeolite 5A, zeolite 13X were researched and the Xenon adsorption of the coconut shell activated carbon modified by KOH(SAC/KOH-1 and SAC/KOH-2) were compared in this paper. The factors of temperature and flow rate that influenced the dynamic adsorption of xenon by 10X were discussed. The order of the Xenon adsorption capacity is as follows: zeolite 10X, SAC/KOH-2, SAC/KOH-1, SAC, zeolite 13X, zeolite 5A.

scholarly journals Clinical Demonstrations of Controlled-Release Tablets Constructed by the Combined Usage of Shellac and Hydroxypropyl Methylcellulose

2021 ◽  
Vol 1 (1) ◽  
pp. 48-59
Author(s):  
Junichiro Wakamatsu ◽  
Kanae Sato ◽  
Keisuke Uryu ◽  
Isafumi Maru
Keyword(s):  
Gastrointestinal Tract ◽  
Controlled Release ◽  
Delivery System ◽  
Clinical Studies ◽  
Blood Glucose Concentration ◽  
Hydroxypropyl Methylcellulose ◽  
Human Study ◽  
Simulated Gastric Fluid ◽  
Simulated Intestinal Fluid ◽  
X Ray

A new tablet system was examined for an intestinal delivery system using hydroxypropyl methylcellulose (HPMC) and shellac. HPMC was incorporated into the inside of the tablet, and shellac was coated on the surface, which was evaluated for its controlled-release property through several dissolution tests, firstly in vitro and then via two kinds of clinical studies with healthy volunteers. The clinical studies were originally designed by employing X-ray photography for the movements of the tablets in the gastrointestinal tract and an electronical device to easily analyze the absorption profile of glucose, a model compound. It was found that the dissolution of the tablet was strongly suppressed in a simulated gastric fluid (pH 1.2) and subsequently started to disintegrate in a simulated intestinal fluid (pH 6.8). The first human study with X-ray photography revealed that the model tablets could pass through the stomach without disintegrating. The controlled release of the tablets was further confirmed via analyses of the AUC, Cmax, and Tmax for the blood glucose concentration with other volunteers. The AUC and Cmax were significantly reduced by using our system, thus concluding that the delivery system combined with the addition of HPMC and a shellac coating unequivocally leads to controlled release in the human gastrointestinal tract.

scholarly journals Release Activity of Encapsulated Lactobacillus plantarum NBRC 3070 in Optimum Alginate - Aloe vera Matrices during Simulated Gastric Fluid (SGF) and Simulated Intestinal Fluid (SIF) Exposure

2017 ◽  
Vol 5 (2) ◽  
Author(s):  
Nur Syahirah Sallehudin ◽  
Khalilah Abdul Khalil ◽  
Maslinda Musa ◽  
Hifa Nazirah Mohd Yazid ◽  
Anida Yusof
Keyword(s):  
Aloe Vera ◽  
Clinical Results ◽  
Gastric Fluid ◽  
Alginate Beads ◽  
Simulated Gastric Fluid ◽  
Intestinal Fluid ◽  
Simulated Intestinal Fluid ◽  
Encapsulated Cells ◽  
Aloe Vera Gel ◽  
Encapsulation Process

Probiotic encapsulation approach has the potential to protect microorganisms and to deliver them into the gut. Because of the promising preclinical and clinical results, probiotics have been incorporated into a range of products. However, there are still many challenges to overcome with respect to the encapsulation process and the conditions prevailing in the gut. Thus in this study, the release activity of encapsulated L. plantarum NBRC 3070 and Aloe vera gel within alginate coated chitosan matrices during simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) exposure were investigated. There were four groups of beads prepared in this study: 1) Encapsulated probiotic and Aloe vera within alginate beads (chitosan coated), 2) Encapsulated probiotic within alginate beads (chitosan coated), 3) Encapsulated probiotic and Aloe vera within alginate beads (uncoated) and 4) Encapsulated probiotic alone within alginate beads (uncoated). Encapsulation process was carried out using extrusion method. The optimized composition of alginate matrix (1.34% w/v) and Aloe vera gel (1.99% w/v) were used.  In order to investigate their release activity, all beads were exposed in Simulated Gastric (SGF) at pH 2.5 and Simulated Intestinal Fluids (SIF) at pH 6.5 for 120 min and 270 min, respectively. Based on the findings, alginate-Aloe vera beads with chitosan coated was able to protect L. plantarum NBRC 3070 during SGF exposure with only 1 log10 cfu/mL reduction. The presence of Aloe vera gel in the beads improved the survivability of the cells. Encapsulated cells were observed successfully slow released of cells from the beads after exposure in SIF. Scan Electron Microscope (SEM) result had shown that cross link activity of the optimum alginate-Aloe vera with chitosan coating resulted in better survival of cells after simulated gastro and able to deliver sufficient probiotic dose to intestinal region. The combinations were able to improve encapsulated cells survivability during low acidic environment passage and release activity into the intestinal target region.   

scholarly journals Survival Survey of Lactobacillus acidophilus In Additional Probiotic Bread

2019 ◽  
Vol 7 (4) ◽  
pp. 588
Author(s):  
Truong Duc Thang ◽  
Le Thi Hanh Quyen ◽  
Hoang Thi Thuy Hang ◽  
Nguyen Thien Luan ◽  
Dang Thi KimThuy ◽  
...  
Keyword(s):  
Lactobacillus Acidophilus ◽  
Xanthan Gum ◽  
Gastric Fluid ◽  
Probiotic Bacteria ◽  
Simulated Gastric Fluid ◽  
Protective Agent ◽  
Intestinal Fluid ◽  
Simulated Intestinal Fluid ◽  
The World ◽  
Alginate Matrix

Bread is a popular food in the world because of its variety and convenience. Currently, studies on the adding probiotics to bread are limited due to the adverse effects of processing, such as baking temperature, aerobic environment to the probiotic bacteria. The objective of this study was to produce probiotic cream bread, in which Lactobacillus acidophilus was microencapsulated with Alginate 2% (A); Alginate 2% + maltodextrin 1% (AM); Alginate 2% + xanthan gum 0.1% (AX); and Alginate 2% + maltodextrin 1% + xanthan gum 0.1% (AMX). Microcapsules were added to the kernel, conducting encapsulation yield investigations, survival in baking, preservation of bread, and in simulated gastric fluid and simulated intestinal fluid conditions after 8 days of storage. The results showed that the addition of xanthan gum enhanced the encapsulation yield, it reached 92.9% and 92.37% in AMX and AX samples, respectively. The viability of L. acidophilus during baking was decreased by 3.64 and 3.75 Log (CFU/bread) in AMX and AM samples, compared to A and AX which were decreased by 4.75 and 4.44 Log (CFU/ bread). In SGF (Simulated Gastric Fluid) and SIF (Simulated Intestinal Fluid) conditions, the AMX microcapsules provide the best probiotic protection among the four tested carriers. The combination of xanthan gum and maltodextrin in alginate matrix, eventually leading to having dual efficiency: First, xanthan gum would act as buffers that reduce acid activity; Second, maltodextrin acting as a protective agent of L. acidophilus against high temperature as well as potential prebiotic that improve the viability of probiotic.

scholarly journals IN VITRO RELEASE STUDIES OF CARBAMAZEPINE TABLETS AND BENZOYL METRONIDAZOLE SUSPENSIONS USING THE FLOW-THROUGH CELL APPARATUS AND SIMULATED GASTROINTESTINAL FLUIDS

2017 ◽  
Vol 9 (4) ◽  
pp. 54 ◽  
Author(s):  
Jose Raul Medina ◽  
Jonathan Hernandez ◽  
Marcela Hurtado
Keyword(s):  
In Vitro Release ◽  
Gastric Fluid ◽  
Simulated Gastric Fluid ◽  
Dissolution Time ◽  
Intestinal Fluid ◽  
Simulated Intestinal Fluid ◽  
Release Studies ◽  
Flow Through ◽  
Vitro Release

Objective: To characterize the in vitro release of carbamazepine tablets and benzoyl metronidazole suspensions using the flow-through cell apparatus and simulated gastrointestinal fluids.Methods: Tegretol® tablets, Flagyl® suspension, and generic formulations of each were tested. Release studies were performed using an automated flow-through cell apparatus. Simulated gastric fluid (with and without pepsin) and simulated intestinal fluid (without pancreatin) at 16 ml/min and fasted state simulated intestinal fluid at 8 ml/min, all at 37.0±0.5 °C, were used as dissolution media. The quantity of dissolved carbamazepine and benzoyl metronidazole was determined at 5-min intervals until 60 min at 285 and 278 nm, respectively. Percentage dissolved at 60 min, mean dissolution time, dissolution efficiency values, and t10%, t25%, t50% and t63.2% were calculated. Mean values for all parameters were compared between the reference and generic formulations using Studentʼs t-test. Dissolution data were fitted to different kinetic models.Results: Simulated gastric fluid without pepsin showed no discriminative capability for carbamazepine tablets. Significant differences were observed between the reference and generic formulations for almost all parameters (*P<0.05). In some cases, the logistic model best described the in vitro release of both drugs.Conclusion: Using an apparatus and media that best simulates the gastrointestinal environment, we identified differences in the rate and extent of dissolution of both drugs that could help to optimise the design of interchangeable formulations. Based on the physicochemical characteristics of carbamazepine and benzoyl metronidazole and the conditions in which the formulations were tested, these differences could be of clinical relevance. 

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