Fabrication of Hydroxyapatite Microcapsules for Controlled Release of Hydrophobic Drug

2016 ◽  
Vol 720 ◽  
pp. 12-16 ◽  
Author(s):  
Takahiko Matsunaga ◽  
Takeshi Yabutsuka ◽  
Shigeomi Takai ◽  
Takeshi Yao

Hydroxyapatite (HAp), a principal component of living bone and teeth, is collecting a lot of attention as a biomaterial owing to its biocompatibility. Also, HAp formed in simulated body fluid (SBF) has flake-like structure and porous body. From these properties, in this study, we fabricated HAp microcapsules encapsulating ibuprofen by attaching the Apatite Nuclei (ANs) on oil droplets containing the ibuprofen and soaking the mixture in SBF. In addition, we evaluated the behavior of drug release from the microcapsules In Vitro.

2005 ◽  
Vol 284-286 ◽  
pp. 153-156 ◽  
Author(s):  
S.B. Cho ◽  
Sang Bae Kim ◽  
Keon Joon Cho ◽  
Ill Yong Kim ◽  
Chikara Ohtsuki ◽  
...  

Novel PMMA-based bone cement using bioactive sol-gel derived CaO-SiO2 powder in order to induce bioactivity as well as to increase its mechanical property. The novel PMMA-based bone cements formed apatite on their surfaces in Simulated Body Fluid(SBF). In the present study, a change in mechanical property of the cement was evaluated using SBF. Before soaking in SBF, its compressive strength showed 80.6±2.1MPa. After soaking in SBF for 2 weeks, 8weeks and 9 weeks, its compressive strength were changed to 83.6±1.6MPa, 87.3±2.4MPa and 85.6±1.8MPa, respectively. It is clear that from the above result, there is no decrease in its compressive strength within 9 weeks soaking in SBF. That it hardly decreases in compressive strength of 7P3S bone cement in SBF is due to the relative small amount of gel powder or its spherical shape and monosize. Therefore, the newly developed PMMA-based cement can bond to the living bone and also be effectively used as bioactive bone cement without decrease in mechanical property.


Biomimetics ◽  
2020 ◽  
Vol 5 (4) ◽  
pp. 57 ◽  
Author(s):  
Francesco Baino ◽  
Seiji Yamaguchi

Some special implantable materials are defined as “bioactive” if they can bond to living bone, forming a tight and chemically-stable interface. This property, which is inherent to some glass compositions, or can be induced by applying appropriate surface treatments on otherwise bio-inert metals, can be evaluated in vitro by immersion studies in simulated body fluid (SBF), mimicking the composition of human plasma. As a result, apatite coating may form on the material surface, and the presence of this bone-like “biomimetic skin” is considered predictive of bone-bonding ability in vivo. This review article summarizes the story and evolution of in vitro bioactivity testing methods using SBF, highlighting the influence of testing parameters (e.g., formulation and circulation of the solution) and material-related parameters (e.g., composition, geometry, texture). Suggestions for future methodological refinements are also provided at the end of the paper.


Author(s):  
Kranthi Kumar Kotta ◽  
L. Srinivas

The present investigation focuses on the development of mucoadhesive tablets of captopril which are designed to prolong the gastric residence time after oral administration. Matrix tablets of captopril were formulated using four mucoadhesive polymers namely guar gum, xanthan gum, HPMC K4M and HPMC K15M and studied for parameters such as weight variation, thickness, hardness, content uniformity, swelling index, mucoadhesive force and in vitro drug release. Tablets formulated Xanthan gum or HPMC K4M with HPMC K15M provide slow release of captopril over period of 12 hr and were found suitable for maintenance portion of oral controlled release tablets. The cumulative % of drug release of formulation F9 and F10 were 90 and 92, respectively. In vitro release from these tablets was diffusion controlled and followed zero order kinetics. The ‘n’ values obtained from the pappas-karsemeyer equation suggested that all the formulation showed drug release by non-fickian diffusion mechanism. Tablets formulated Xanthan gum or HPMC K4M with HPMC K15M (1:1) were established to be the optimum formulation with optimum bioadhesive force, swelling index & desired invitro drug release. This product was further subjected to stability study, the results of which indicated no significant change with respect to Adhesive strength and in vitro drug release study.


2020 ◽  
Vol 15 ◽  
Author(s):  
Balaji Maddiboyina ◽  
Vikas Jhawat ◽  
Gandhi Sivaraman ◽  
Om Prakash Sunnapu ◽  
Ramya Krishna Nakkala ◽  
...  

Background: Venlafaxine HCl is a selective serotonin reuptake inhibitor which is given in the treatment of depression. The delivery of the drug at a controlled rate can be of great importance for prolonged effect. Objective: The objective was to prepare and optimize the controlled release core in cup matrix tablet of venlafaxine HCl using the combination of hydrophilic and hydrophobic polymers to prolong the effect with rate controlled drug release. Methods: The controlled release core in cup matrix tablets of venlafaxine HCl were prepared using HPMC K5, K4, K15, HCO, IPA, aerosol, magnesium sterate, hydrogenated castor oil and micro crystalline cellulose PVOK-900 using wet granulation technique. Total ten formulations with varying concentrations of polymers were prepared and evaluated for different physicochemical parameters such FTIR analysis for drug identification, In-vitro drug dissolution study was performed to evaluate the amount of drug release in 24 hrs, drug release kinetics study was performed to fit the data in zero order, first order, Hixson–crowell and Higuchi equation to determine the mechanism of drug release and stability studies for 3 months as observed. Results: The results of hardness, thickness, weight variation, friability and drug content study were in acceptable range for all formulations. Based on the In vitro dissolution profile, formulation F-9 was considered to be the optimized extending the release of 98.32% of drug up to 24 hrs. The data fitting study showed that the optimized formulation followed the zero order release rate kinetics and also compared with innovator product (flavix XR) showed better drug release profile. Conclusion: The core-in-cup technology has a potential to control the release rate of freely water soluble drugs for single administration per day by optimization with combined use of hydrophilic and hydrophobic polymers.


2015 ◽  
Vol 23 (1) ◽  
pp. 1-14
Author(s):  
Sudirman Sahid ◽  
◽  
Nor Shahida Kader Bashah ◽  
Salina Sabudin ◽  
◽  
...  

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2137
Author(s):  
Lubomir Medvecky ◽  
Maria Giretova ◽  
Radoslava Stulajterova ◽  
Lenka Luptakova ◽  
Tibor Sopcak

A modified one-step process was used to prepare tetracalcium phosphate/monetite/calcium sulfate hemihydrate powder cement mixtures (CAS). The procedure allowed the formation of monetite and calcium sulfate hemihydrate (CSH) in the form of nanoparticles. It was hypothesized that the presence of nanoCSH in small amounts enhances the in vitro bioactivity of CAS cement in relation to osteogenic gene markers in mesenchymal stem cells (MSCs). The CAS powder mixtures with 15 and 5 wt.% CSH were prepared by milling powder tetracalcium phosphate in an ethanolic solution of both orthophosphoric and sulfuric acids. The CAS cements had short setting times (around 5 min). The fast setting of the cement samples after the addition of the liquid component (water solution of NaH2PO4) was due to the partial formation of calcium sulfate dihydrate and hydroxyapatite before soaking in SBF with a small change in the original phase composition in cement powder samples after milling. Nanocrystalline hydroxyapatite biocement was produced by soaking of cement samples after setting in simulated body fluid (SBF). The fast release of calcium ions from CAS5 cement, as well as a small rise in the pH of SBF during soaking, were demonstrated. After soaking in SBF for 7 days, the final product of the cement transformation was nanocrystalline hydroxyapatite. The compressive strength of the cement samples (up to 30 MPa) after soaking in simulated body fluid (SBF) was comparable to that of bone. Real time polymerase chain reaction (RT-PCR) analysis revealed statistically significant higher gene expressions of alkaline phosphatase (ALP), osteonectin (ON) and osteopontin (OP) in cells cultured for 14 days in CAS5 extract compared to CSH-free cement. The addition of a small amount of nanoCSH (5 wt.%) to the tetracalcium phosphate (TTCP)/monetite cement mixture significantly promoted the over expression of osteogenic markers in MSCs. The prepared CAS powder mixture with its enhanced bioactivity can be used for bone defect treatment and has good potential for bone healing.


Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 667
Author(s):  
Zexin Wang ◽  
Fei Ye ◽  
Liangyu Chen ◽  
Weigang Lv ◽  
Zhengyi Zhang ◽  
...  

In this work, ZK60 magnesium alloy was employed as a substrate material to produce ceramic coatings, containing Ca and P, by micro-arc oxidation (MAO). Atmospheric plasma spraying (APS) was used to prepare the hydroxyapatite layer (HA) on the MAO coating to obtain a composite coating for better biological activity. The coatings were examined by various means including an X-ray diffractometer, a scanning electron microscope and an energy spectrometer. Meanwhile, an electrochemical examination, immersion test and tensile test were used to evaluate the in vitro performance of the composite coatings. The results showed that the composite coating has a better corrosion resistance. In addition, this work proposed a degradation model of the composite coating in the simulated body fluid immersion test. This model explains the degradation process of the MAO/APS coating in SBF.


Gels ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 110
Author(s):  
Muhammad Suhail ◽  
Chih-Wun Fang ◽  
Arshad Khan ◽  
Muhammad Usman Minhas ◽  
Pao-Chu Wu

The purpose of the current investigation was to develop chondroitin sulfate/carbopol-co-poly(acrylic acid) (CS/CBP-co-PAA) hydrogels for controlled delivery of diclofenac sodium (DS). Different concentrations of polymers chondroitin sulfate (CS), carbopol 934 (CBP), and monomer acrylic acid (AA) were cross-linked by ethylene glycol dimethylacrylate (EGDMA) in the presence of ammonium peroxodisulfate (APS) (initiator). The fabricated hydrogels were characterized for further experiments. Characterizations such as Scanning electron microscopy (SEM), Thermogravimetric analysis (TGA), Differential scanning calorimetry (DSC), Powder X-ray diffractometry (PXRD), and Fourier transform infrared spectroscopy (FTIR) were conducted to understand the surface morphology, thermodynamic stability, crystallinity of the drug, ingredients, and developed hydrogels. The swelling and drug release studies were conducted at two different pH mediums (pH 1.2 and 7.4), and pH-dependent swelling and drug release was shown due to the presence of functional groups of both polymers and monomers; hence, greater swelling and drug release was observed at the higher pH (pH 7.4). The percent drug release of the developed system and commercially available product cataflam was compared and high controlled release of the drug from the developed system was observed at both low and high pH. The mechanism of drug release from the hydrogels followed Korsmeyer–Peppas model. Conclusively, the current research work demonstrated that the prepared hydrogel could be considered as a suitable candidate for controlled delivery of diclofenac sodium.


Author(s):  
Farhana Sultan ◽  
Himansu Chopra ◽  
Gyanendra Kumar Sharma

Microsponge containing Luliconazole (LCZ) with different proportion of drug:polymer (Ethyl cellulose and Eudragit RS 100) were obtained efficiently using Quasi-emulsion solvent diffusion method. Luliconazole is an anti-fungal drug used for the topical delivery. The purpose of the microsponge formulation is to control the release of LCZ drug to the skin through Microsponge Delivery System (MDS) known to be the novel technique which overcome the maximum concentration of active ingredient, frequency doses, and skin irritation. The prepared microsponges were examined using drug content, % production yield, % entrapment efficiency and in-vitro drug release. The formulation were subjected to in-vitro drug release studies for 6 hr in which it was concluded that Ethyl cellulose microsponges formulated by drug:polymer (1:1) and Eudragit RS 100 microsponges formulated by drug:polymer (1:3) showed maximum controlled release i.e., Increase in drug:polymer ratio (1:1 to 1:9) increased the production yield and entrapment efficiency of microsponges using Ethyl cellulose with no significant effect for Eudragit RS 100.Therefore, both formulation F1 and F2 was dispersed in carbopol gel preparation for controlled delivery of LCZ to the skin. Various physical parameters like pH, spreadability, viscosity and in-vitro drug diffusion studies were evaluated for the prepared gel formulations. Microsponge gel formulation i.e., FG1 showed better results for controlled release of 89.40% as compared to FG2 i.e., 92.18% over the period of 12 hrs which is performed in Franz Diffusion Cell. On basis of in-vitro diffusion studies for LCZ gel formulation, microsponges using Ethyl cellulose (FG1) was found to be best for its controlled release of LCZ for 12 hrs and followed zero order kinetics. Hence, formulated LCZ loaded gel have potential to treat fungal infections i.e., tinea pedis, tinea cruris and tinea corporis.


Sign in / Sign up

Export Citation Format

Share Document