Preparation and Degradation Properties of Hydroxyethyl Chitosan-g-Poly(D,L-Lactide) Copolymers

2012 ◽  
Vol 457-458 ◽  
pp. 308-313
Author(s):  
Bing Hong Luo ◽  
Jian Hua Li ◽  
Wan Xu ◽  
Chang Ren Zhou
Keyword(s):  
Ring Opening ◽  
Ph Value ◽  
Saline Water ◽  
Feed Ratio ◽  
Casting Method ◽  
Composition And Structure ◽  
Solution Casting Method ◽  
Lactide Copolymers ◽  
Degradation Properties

The goal of the present study was to investigate the degradation of hydroxyethyl chitosan-g-poly(D,L-lactide) (HECS-g-PDLLA) copolymers in vitro. For this purpose, HECS-g-PDLLA copolymers were firstly synthesized by bulk ring-opening polymerization with different nD,L-lactide:naminoglucoside feed ratio. Then, a series of poly(D,L-lactide), chitosan and HECS-g-PDLLA copolymers films were prepared by solution casting method, and their degradation were carried out in vitro in saline water at 37 °C. The degradation properties were investigated by measurement of pH value, weight loss, and changes in the composition and structure of the HECS-g-PDLLA copolymers films with time. Results showed that the degradation of the HECS-g-PDLLA copolymers occurred firstly on the poly(D,L-lactide) side chains. The degradation rate of the graft copolymers obviously faster than that of CS, and can be controlled by changing the value of nD,L-lactide:naminoglucoside. Due to the alkalinity of CS, the pH value of saline water for HECS-g-PDLLA copolymers degradation higher than that of PDLLA.

Formulation and Evaluation of Chitosan-Polyaniline Nanocomposites for Controlled Release of Anticancer Drug Doxorubicin

2018 ◽  
Vol 8 (2) ◽  
Author(s):  
Dillip Kumar Behera ◽  
Kampal Mishra ◽  
Padmolochan Nayak
Keyword(s):  
Tensile Strength ◽  
Drug Release ◽  
Nanocomposite Films ◽  
Casting Method ◽  
Sustained Drug Release ◽  
In Vitro Drug Release ◽  
Clay Particles ◽  
Solution Casting Method ◽  
Nanoclay Content

In this present work, chitosan (CS) crosslink with polyaniline (PANI) with montmorilonite (MMT) called as (CSPANI/MMT) and CS crosslink with PANI without MMT called as (CS-PANI) were prepared by employing the solution casting method. Further the formation of nanocomposites CS-PANI/MMT and CS-PANI were investigated using XRD, FTIR, SEM and tensile strength. Water uptake and swelling ratio of the CS-PANI and CS-PANI/MMT were found to decrease with increase in concentration of clay. Mechanical properties of the CS-PANI and CS-PANI/MMT were assessed in terms of tensile strength and extensibility using texture analyzer. Increase in tensile strength and reduction in extensibility was reported with increase in the nanoclay content. In vitro drug release study on CS-PANI and CS-PANI/MMT indicated pronounced sustained release of doxorubicin by the incorporation of clay particles in the CS polymer matrix. Overall CSPANI/MMT nanocomposite films exhibited improved mechanical and sustained drug release properties than CS-PANI.

scholarly journals Synthesis of Alginate/Nanocellulose bionanocomposite for in vitro delivery of Ampicillin

2018 ◽  
Vol 9 (4) ◽  
pp. 107
Author(s):  
R Poonguzhali ◽  
S Khaleel Basha ◽  
V Sugantha Kumari
Keyword(s):  
Drug Release ◽  
Sustained Release ◽  
Physicochemical Properties ◽  
Immediate Release ◽  
Prolonged Release ◽  
Solution Casting ◽  
Casting Method ◽  
Solution Casting Method ◽  
Nanocellulose Film

<p>In this study Ampicillin drug loaded with alginate and nanocellulose film was prepared by solution casting method. Nanocellulose and ampicillin incorporated into alginate to improve both mechanical and swelling property. The formulated ampicillin loaded Alg/NC film gave acceptable physicochemical properties compared with Alg-amp film and was able to deliver the drug in a prolonged release pattern. <em>In vitro</em> drug release showed that alginate, could provide an immediate release of ampicillin with further enhanced nanocellulose, and followed by a sustained release over 500 min of the remaining drug. The present study exhibited a simple and useful approach to systematically design for providing drug release profiles.</p>

scholarly journals The Degradation Properties of MgO Whiskers/PLLA Composite In Vitro

2018 ◽  
Vol 19 (9) ◽  
pp. 2740 ◽  
Author(s):  
Yun Zhao ◽  
Bei Liu ◽  
Hongwei Bi ◽  
Jinjun Yang ◽  
Wei Li ◽  
...  
Keyword(s):  
Ph Value ◽  
Composite Films ◽  
Phosphate Buffer Solution ◽  
Buffer Solution ◽  
In Vitro Degradation ◽  
Final Weight ◽  
Cell Affinity ◽  
Degradation Properties ◽  
Composite Samples

In this study, composite films of stearic acid–modified magnesium oxide whiskers (Sa–w-MgO)/poly-l-lactic acid (PLLA) were prepared through solution casting, and the in vitro degradation properties and cytocompatibility of the composites with different whisker contents were investigated. The results showed that the degradation behavior of the composite samples depended significantly on the whisker content, and the degradation rate increased with the addition of MgO content. Furthermore, the degradation of the composites with higher contents of whiskers was influenced more severely by the hydrophilicity and pH value, leading to more final weight loss, but the decomposition rate decreased gradually. Furthermore, the pH value of the phosphate buffer solution (PBS) was obviously regulated by the dissolution of MgO whiskers through neutralization of the acidic product of PLLA degradation. The cytocompatibility of the composites also increased remarkably, as determined from the cell viability results, and was higher than that of PLLA at the chosen whisker content. This was beneficial for the cell affinity of the material, as it notably led to an enhanced biocompatibility of the PLLA, in favor of promoting cell proliferation, which significantly improved its bioactivity, as well.

scholarly journals FORMULATION AND EVALUATION OF GRAPHENE GRAFTED CHITOSAN/POLYANILINE NANOCOMPOSITES FOR CONTROLLED RELEASE OF ANTICANCER DRUG DOXORUBICIN

2019 ◽  
pp. 138-143
Author(s):  
SUCHISMITA MOHANTY ◽  
SUBRATA SARANGI ◽  
GOURI SANKAR ROY
Keyword(s):  
Drug Release ◽  
Biological Fluid ◽  
Feed Ratio ◽  
X Ray Diffraction ◽  
Casting Method ◽  
Drug Release Rate ◽  
In Vitro Drug Release ◽  
X Ray ◽  
Model Drug

Objective: The purpose of the present study was to functionalized graphene (f-GE) grafted chitosan (CS)/Polyaniline (PANI) with Montmorillonite (MMT) was different feed ratio known as f-GE-g-(CS/MMT-PANI). Methods: The prepared f-GE-g-(CS/MMT-PANI) was formulated using the solvent casting method. The prepared nanocomposites were characterized by X-Ray Diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM), Thermogravimetric analysis (TGA), thermogravimetric (DTG) and swelling in stimulated in the different biological fluid. The model drug Doxorubicin (DOX) was used for controlled drug delivery purpose. Results: From FTIR result was clearly demonstrated that the model drug DOX did not change in any molecular level at f-GE-(CS/MMT-PANI) (i.e. at<10 nm scale). Additionally, in DSC result, DOX was interacted with nanocomposites at scale>100 nm level. With CS as the carrier, 60% of the drug was released in SIF for the initial 120 min and this increased to 80–82% with f-GE-g-CS/MMT/PANI matrix. But in SGF, CS as the carrier, 46% of the drug was released in 140 min and this increased to 78% with f-GE-g-CS/MMT/PANI. In vitro drug release system was carried out by Korsmeyer Peppas’s power law. DOX and other drugs like Doxorubicin (DOX) was presented an exceptional higher drug result in different pH medium. Conclusion: It was observed that CS/MMT was decreasing less drug release rate compared to f-GE-g-(CS/MMT-PANI). So that it can be clearly understood that f-GE-g-(CS/MMT-PANI) grafted nanocomposites have enhanced drug release activity in different pH medium.

Rhenium-188 Labeled Hydroxyapatite and Rhenium-188 Sulfur Colloid

1997 ◽  
Vol 36 (02) ◽  
pp. 71-75 ◽  
Author(s):  
S. Glatz ◽  
S. N. Reske ◽  
K. G. Grillenberger
Keyword(s):  
Synovial Fluid ◽  
Ph Value ◽  
Surgical Removal ◽  
Radiation Synovectomy ◽  
Sulfur Colloid ◽  
Target Organs ◽  
Aseptic Conditions ◽  
In Vitro Stability ◽  
Potential Use

Summary Aim: One therapeutic approach to rheumatoid arthritis and other inflammatory arthropathies besides surgical removal of inflamed synovium is radiation synovectomy using beta-emitting radionuclides to destroy the affected synovial tissue. Up to now the major problem associated with the use of labeled particles or colloids has been considerable leakage of radionuclides from the injected joint coupled with high radiation doses to liver and other non target organs. In this study we compared 188Re labeled hydroxyapatite particles and 188Re rhenium sulfur colloid for their potential use in radiation synovectomy. Methods: To this end we varied the labeling conditions (concentrations, pH-value, heating procedure) and analyzed the labeling yield, radiochemical purity, and in vitro stability of the resulting radiopharmaceutical. Results: After optimizing labeling conditions we achieved a labeling yield of more than 80% for 188Re hydroxyapatite and more than 90% for the rhenium sulfur colloid. Both of the radiopharmaceuticals can be prepared under aseptic conditions using an autoclav for heating without loss of activity. In vitro stability studies using various challenge solutions (water, normal saline, diluted synovial fluid) showed that 188Re labeled hydroxyapatite particles lost about 80% of their activity within 5 d in synovial fluid. Rhenium sulfur colloid on the other hand proved to be very stable with a remaining activity of more than 93% after 5 d in diluted synovial fluid. Conclusion: These in vitro results suggest that 188Re labeled rhenium sulfur colloid expects to be more suitable for therapeutic use in radiation synovectomy than the labeled hydroxyapatite particles.

In vitro Lipolysis as a Tool for the Establishment of IVIVC for Lipid-Based Drug Delivery Systems

2019 ◽  
Vol 16 (8) ◽  
pp. 688-697
Author(s):  
Ravinder Verma ◽  
Deepak Kaushik
Keyword(s):  
Drug Delivery ◽  
Ph Value ◽  
Electron Paramagnetic Resonance Spectroscopy ◽  
Rapid Screening ◽  
Resonance Spectroscopy ◽  
Fed State ◽  
In Vitro Lipolysis ◽  
Ph Stat

: In vitro lipolysis has emerged as a powerful tool in the development of in vitro in vivo correlation for Lipid-based Drug Delivery System (LbDDS). In vitro lipolysis possesses the ability to mimic the assimilation of LbDDS in the human biological system. The digestion medium for in vitro lipolysis commonly contains an aqueous buffer media, bile salts, phospholipids and sodium chloride. The concentrations of these compounds are defined by the physiological conditions prevailing in the fasted or fed state. The pH of the medium is monitored by a pH-sensitive electrode connected to a computercontrolled pH-stat device capable of maintaining a predefined pH value via titration with sodium hydroxide. Copenhagen, Monash and Jerusalem are used as different models for in vitro lipolysis studies. The most common approach used in evaluating the kinetics of lipolysis of emulsion-based encapsulation systems is the pH-stat titration technique. This is widely used in both the nutritional and the pharmacological research fields as a rapid screening tool. Analytical tools for the assessment of in vitro lipolysis include HPLC, GC, HPTLC, SEM, Cryo TEM, Electron paramagnetic resonance spectroscopy, Raman spectroscopy and Nanoparticle Tracking Analysis (NTA) for the characterization of the lipids and colloidal phases after digestion of lipids. Various researches have been carried out for the establishment of IVIVC by using in vitro lipolysis models. The current publication also presents an updated review of various researches in the field of in vitro lipolysis.

Improving Topical Skin Delivery of Monocrotaline Via Liposome Gel-based Nanosystems

2019 ◽  
Vol 16 (10) ◽  
pp. 940-950 ◽  
Author(s):  
Jiandong Yu ◽  
Zhi Chen ◽  
Yan-zhi Yin ◽  
Chaoyuan Tang ◽  
Enying Hu ◽  
...  
Keyword(s):  
Gradient Method ◽  
Encapsulation Efficiency ◽  
Ph Value ◽  
Topical Administration ◽  
Ph Gradient ◽  
Stability Factor ◽  
Buffer Solution ◽  
Skin Delivery ◽  
Skin Retention

Background: In this study, a liposomal gel based on a pH-gradient method was used to increase the skin-layer retention of monocrotaline (MCT) for topical administration. Methods: Using the Box-Behnken design, different formulations were designed to form liposome suspensions with optimal encapsulation efficiency (EE%) and stability factor (KE). In order to keep MCT in liposomes and accumulate in skin slowly and selectively, MCT liposome suspensions were engineered into gels. Results: A pH-gradient method was used to prepare liposome suspensions. The optimal formulation of liposome suspensions (encapsulation efficiency: 83.10 ± 0.21%) was as follows: MCT 12 mg, soybean phosphatidyl choline (sbPC) 200 mg, cholesterol (CH) 41 mg, vitamin E (VE) 5 mg, and citric acid buffer solution (CBS) 4.0 10 mL (pH 7.0). The final formulation of liposomal gels consisted of 32 mL liposome suspensions, 4.76 mL deionized water, 0.40 g Carbopol-940, 1.6 g glycerol, 0.04 g methylparaben, and a suitable amount of triethanolamine for pH value adjustment. The results of in vitro drug release showed that MCT in liposomal gels could be released in 12 h constantly in physiological saline as a Ritger-Peppas model. Compared with plain MCT in gel form, liposomal MCT in gel had higher skin retention in vitro. Conclusion: In this study, liposomal gels were formed for greater skin retention of MCT. It is potentially beneficial for reducing toxicities of MCT by topical administration with liposomal gel.

scholarly journals Fabrication and characterization of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) modified with nano-montmorillonite biocomposite

e-Polymers ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 038-046
Author(s):  
Xu Yan ◽  
Wanru Zhou ◽  
Xiaojun Ma ◽  
Binqing Sun
Keyword(s):  
Thermal Stability ◽  
Oxygen Permeability ◽  
Water Vapor Permeability ◽  
Barrier Properties ◽  
Nucleating Agent ◽  
Vapor Permeability ◽  
Casting Method ◽  
Increasing Trend ◽  
Solution Casting Method

Abstract In this study, a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) modified with nano-montmorillonite biocomposite (MMT/PHBH) was fabricated by solution-casting method. The results showed that the addition of MMT increased the crystallinity and the number of spherulites, which indicated that MMT was an effective nucleating agent for PHBH. The maximum decomposition peak of the biocomposites moved to a high temperature and residue presented an increasing trend. The biocomposites showed the best thermal stability at 1 wt% MMT. Compared with PHBH, 182.5% and 111.2% improvement in elastic modulus and tensile strength were obtained, respectively. Moreover, the oxygen permeability coefficient and the water vapor permeability of MMT/PHBH biocomposites decreased by 43.9% and 6.9%, respectively. It was also found that the simultaneous enhancements on the crystallizing, thermal stability, mechanical, and barrier properties of biocomposites were mainly caused by the formation of intercalated structure between PHBH and MMT.

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