Drug Delivery Systems Based on Hydroxyapaptite-coated Poly(lactic-co-glycolic acid) Microspheres

2007 ◽  
Vol 1063 ◽  
Author(s):  
Qingguo Xu ◽  
Jan T Czernuszka

ABSTRACTNegatively charged poly(lactic-co-glycolic acid) (PLGA) microspheres were prepared by the solid-in-oil-in-water (s/o/w) method using the anionic surfactant, sodium dodecyl sulfate (SDS), and a hydrophilic antibiotic (amoxicillin) was encapsulated with an encapsulation efficiency of 40.6%. A layer of hydroxyapatite (HA) was coated on these negatively charged PLGA microspheres by a dual constant composition method in 3 - 6 hours. The HA-coated PLGA microspheres (HPLG) had a core-shell structure and were characterised by scanning electron microscopy, focused ion beam microscopy, energy-dispersive X-ray spectrometry, X-ray diffraction and Fourier transform infrared spectroscopy. Sustained release of amoxicillin from HPLG for at least 31 days was shown from in-vitro drug release experiments. A typical triphasic drug release profile had been observed for PLGA and HPLG microspheres. This device exhibited two desirable properties: the sustained release from PLGA and osteoconductivity from HA. Hence, it could have potential applications in delivering drugs to treat bone disorders or infections.

2011 ◽  
Vol 311-313 ◽  
pp. 1751-1754
Author(s):  
Gui Yu Li ◽  
Xi Hong Lu ◽  
Xue Hu Li ◽  
Lei Tao ◽  
Jian Ping Liang

Drug was encapsulated in a novel copolymers of poly(lactic-co-glycolic acid) (PLGA) to investigate the sustained-release formulation of drug loaded polymer microspheres delivery system. Used a modified solid-in-oil-in-water (S/O/W) emulsion solvent evaporation method to prepare microspheres, its morphology and particle size distribution were estimated by scanning electron microscopy (SEM), the profile of in vitro drug release were assessed by High performance liquid chromatography (HPLC). Finally, an stable release buffer was utilized to obtain a detailed drug release profile, which was analyzed by HPLC also. Results showed that the microspheres morphology, encapsulation efficiency and the cumulative drug release efficiency were appropriate for veterinary medicine using. The modified preparation method was simple and optimized, PLGA microspheres with excellent controlled-release characteristics may serve as drug delivery carrier and may prolong the drug sustained-release effect.


Author(s):  
Bhikshapathi D. V. R. N. ◽  
Arun Kumar Jarathi ◽  
Suresh Gande ◽  
Viswaja Medipally ◽  
Ramesh Bomma

Background and the purpose of the study: Risedronate sodium inhibits osteoclast bone resorption and modulates bone metabolism. Risedronate has a high affinity for hydroxyapatite crystals in bone and is a potent antiresorptive agent. In the present investigation efforts were made to improve the bioavailability of risedronate sodium by increasing the residence time of the drug through sustained-release matrix capsule formulation via gastroretentive mechanism. Capsules were prepared by wet granulation technique. The influence of gel forming agents, amount of risedronate and total weight of capsules on physical properties, in vitro buoyancy, drug release, FTIR, DSC, X-ray studies were investigated. The release mechanisms were explored and explained by applying zero order, first order, Higuchi and Korsmeyer equations. The selected formulations were subjected to stability study at 40 °C/75% RH, 25 °C/60% RH for the period of three months. For all formulations, kinetics of drug release from capsules followed Higuchi’s square root of time kinetic treatment heralding diffusion as predominant mechanism of drug release. Formulation containing 25 mg HPMC K4M and 75 mg HPMC K100 LV (F-8) showed zero order release profile. There was no significant change in the selected formulation, when subjected to accelerated stability conditions over a period of three months. X-ray imaging in six healthy human volunteers revealed a mean gastric retention period of 5.60 ± 0.77 hrs for the selected formulation. Stable, sustained release effervescent floating capsules of risedronate sodium could be prepared by wet granulation technique.  


2020 ◽  
Vol 12 ◽  
Author(s):  
Sagar R. Pardeshi ◽  
Harshal A. Mistari ◽  
Rakhi S. Jain ◽  
Pankaj R. Pardeshi ◽  
Rahul L. Rajput ◽  
...  

Background: Moxifloxacin is a BCS class I drug used in the treatment of bacterial conjunctivitis and keratitis. Despite its high water solubility, it possesses limited bioavailability due to anatomical and physiological constraints associated with the eyes which required multiple administrations to achieve a therapeutic effect. Objective: In order to prolong drug release and to improve antibacterial efficacy for the treatment of bacterial keratitis and conjunctivitis, moxifloxacin loaded nanoemulsion was developed. Methods: The concentration of oil (oleic acid), surfactant (tween 80), and cosurfactant (propylene glycol) were optimized by employing a 3-level 2-factorial design of experiment for the development of nanoemulsion. The developed nanoemulsion was characterized by particle size distribution, viscosity, refractive index, pH, drug content and release, transmission electron microscopy (TEM), and antibacterial study. The compatibility of the drug with the excipients was accessed by Fourier transform infrared spectroscopy (FTIR). Result: The average globule size was found to be 198.20 nm. The TEM study reveals the globules were nearly spherical and are well distributed. In vitro drug release profile for nanoemulsion shown sustained drug release (60.12% at the end of 6 h) compared to drug solution, where complete drug released within 2 h. The antibacterial effectiveness of the drug-loaded nanoemulsion was improved against S. aureus compared with the marketed formulation. Conclusion: The formulated sustained release nanoemulsion could be a promising alternative to eye drop with improved patient compliance by minimizing dosing frequency with improved antibacterial activity.


2019 ◽  
Vol 11 (2) ◽  
pp. 142-153
Author(s):  
Rutuja V. Deshmukh ◽  
Pavan Paraskar ◽  
S. Mishra ◽  
Jitendra Naik

Background: Nateglinide is an antidiabetic drug having biological half-life 1.5 h which shows a concise effect. Graphene oxide along with chitosan can be used as a nanocarrier for sustained release of Nateglinide. Objective: To develop Nateglinide loaded graphene oxide-chitosan nanocomposites and to evaluate for different characterization studies. Methods: Graphene Oxide (GO) was synthesized by improved hummer’s method and drug-loaded Graphene oxide - chitosan nanocomposites were prepared. Box Behnken design was used to carry out experiments. The nanocomposites were characterized for encapsulation efficiency and drug release. Morphology was studied using field emission scanning electron microscope and transmission electron microscope. An interaction between drug, polymer and GO was investigated by Fourier transform infrared spectroscopy and X-ray diffractometer along with in vitro drug release study. Results: The statistical evaluation of the design showed linear and quadratic models which are significant models for encapsulation efficiency (R1 0.6883, 0.9473) and drug loading (R2 0.6785, 0.9336), respectively. Fourier transform infrared spectroscopy showed the compatibility of GO, Chitosan and Nateglinide. X-ray diffractometer reveals the change in degree of crystallinity of drug. FE-SEM and TEM images confirmed the distribution of the drug within the nanocomposites. Design expert reveals that the concentration of GO has great influence on encapsulation efficiency. In Vitro drug release showed the sustained release of drug over the period of 12 h. Conclusion: GO-Chitosan nanocomposites can be used as a sustained release carrier system for Nateglinide to reduce dose frequency of drug as well as its probable side effects.


2013 ◽  
Vol 2 (10) ◽  
pp. 165-169 ◽  
Author(s):  
Manivannan Rangasamy ◽  
Venkata Krishna Reddy Palnati ◽  
Lakshmi Narayana Rao Bandaru

The present study involves in the formulation and evaluation of sustained release tablets of Voriconazole (250mg). The objective of the present study was to formulate Voriconazole sustained release tablets by wet granulation method by using natural (Xanthan gum, Karaya gum) and semi synthetic polymers (HPMC K100M). Lactose was used as diluting agent, Magnesium stearate was used as a lubricant and Talc was used as a glident. These sustained release tablets can release the drug up to 12 hours in predetermined rate. The formulated powder blend was evaluated for bulk density, tapped density, compressibility index and angle of repose. The formulated tablets were evaluated for physical characteristics of sustained release tablets such as thickness, hardness, friability, weight variation and drug content. The results of the formulations found to be within the limits specified in official books. The tablets were evaluated for In-vitro drug release studies by using USP type I dissolution test apparatus. The dissolution test was performed in 0.1 N HCL for 2 hr and phosphate buffer pH 6.8 for 10hrs. The in-vitro cumulative drug release profile of all formulations F1-F10 at 12 hours showed 84.25% to 99.82% drug release, respectively. From the data it was clear that by increasing the amount of polymer in the formulation the amount of drug release was decreased. Hence, Formulation F9 was the most promising formulation as it gives satisfactory release (99.82%) for 12 hours and F9 found to be the best formulation.DOI: http://dx.doi.org/10.3329/icpj.v2i10.16410 International Current Pharmaceutical Journal, September 2013, 2(10): 165-169


2022 ◽  
pp. 088532822110640
Author(s):  
Shengtang Li ◽  
Xuewen Shi ◽  
Bo Xu ◽  
Jian Wang ◽  
Peng Li ◽  
...  

Currently, the treatment of osteomyelitis poses a great challenge to clinical orthopedics. The use of biodegradable materials combined with antibiotics provides a completely new option for the treatment of osteomyelitis. In this study, vancomycin hydrochloride (VANCO) loaded poly (lactic-co-glycolic acid) (PLGA) microspheres were prepared by a double emulsion solvent evaporation method, and the in vitro drug release behaviors of the drug loaded microspheres were explored after coating with different concentrations of silk fibroin (SF). Drug loading, encapsulation efficiency, Scanning electron microscopy, particle size analysis, Fourier transform infrared spectroscopy, hydrophilicity, in vitro drug release, and in vitro antibacterial activity were evaluated. The results showed that the drug loading of vancomycin loaded PLGA microspheres was (24.11 ±1.72)%, and the encapsulation efficiency was (48.21 ±3.44)%. The in vitro drug release indicated that the drug loaded microspheres showed an obvious initial burst release, and the drug loaded microspheres coated with SF could alleviate the initial burst release in varying degrees. It also can reduce the amount of cumulative drug release, and the effect of microspheres coated with 0.1% concentration of SF is the best. The time of in vitro drug release in different groups of drug loaded microspheres can be up to 28 days. The microspheres coated with (0.1%SF) or without (0%SF) SF showed a cumulative release of (82.50±3.51)% and (67.70±3.81)%,respectively. Therefore, the surface coating with SF of vancomycin loaded microspheres can alleviate the initial burst release, reduce the cumulative drug release, potentially prolong the drug action time, and improve the anti-infection effect.


2021 ◽  
Vol 18 ◽  
Author(s):  
Atef Mohammed Qasem Ahmed ◽  
Li-Qing Chen ◽  
Huan-Huan Du ◽  
Wei Sun ◽  
Qing-Ri Cao

Purpose: Traditional dosage forms of granisetron (GRN) decrease patient compliance associated with repeated drug administration because of the short half-life of the drug. Methods: In this study, novel GRN-loaded polylactic-co-glycolic acid (PLGA) sustained release microspheres were prepared for the first time via a dropping-in-liquid emulsification technique. The effect of various factors, such as pH of the outer phase, Tween80, polyvinyl alcohol (PVA) concentrations, and hardening process, on the encapsulation efficiency (EE), drug loading (DL), and particle size of microspheres were extensively studied. The physicochemical properties, including drug release, surface morphology, crystallinity, thermal changes, and molecular interactions, were also studied. Results: GRN has a pH-dependent solubility and showed a remarkably high solubility under an acidic condition. The EE of the alkaline medium (pH 8) was higher than that of the acidic medium (pH 4.0). EE and DL decreased in the presence of Tween80 in the outer phase, whereas EE significantly increased during hardening. The particle size of microspheres was not affected by PVA and Tween80 concentrations, but it was influenced by PVA volume and hardening. X-ray diffraction and differential scanning calorimetry results showed that the physical state of the drug changed from a crystalline form to an amorphous form, thereby confirming that the drug was encapsulated into the PLGA matrix. Fourier transform-infrared spectroscopy confirmed that some molecular interactions occurred between the drug and the polymer. GRN-loaded PLGA microspheres showed sustained release profiles of over 90% on week 3. Conclusion: GRN-loaded PLGA microspheres with sustained release were successfully prepared, and they exhibited a relatively high EE without Tween 80 as an emulsifier and with hardening process.


Author(s):  
Nilesh N. Mahajan ◽  
Pooja Wadhavane ◽  
Debarshi Kar Mahapatra

Objective: The existing investigation represents a challenge in formulating etodolac oral controlled release tablets employing five most prominent hydrophilic release rate retardant polymers like HPMC K100M, HPMC K4M, Carbopol 934P, Eudragit RS100, and Polyvinyl pyrrolidone K90 which are USFDA approved non-toxic substances, cost-effective, and easily available.Methods: The tablets were manufactured by wet granulation method along with talc, anhydrous lactose, and magnesium stearate. The pre-compression attributes of the produced granules and the post-compression characteristics were assessed according to the specified protocols. The formulations were accessed for their ability to release the drug in the simulated gastric media and the obtained results were fitted into various kinetic models to determine the probable drug release mechanism(s). A short-term stability study (for 90 days duration) was also performed.Results: The prepared granules demonstrated superior flow properties and packing ability, whereas the fabricated sustained release matrix batches showed excellent mechanical characteristics. The in vitro drug release profile of the hypromellose, carbomer, eudragit and povidone based sustained release matrix tablet formulations expressed drug release for the period of 12 hr following the diffusion cum erosion mechanism(s) (termed as anomalous diffusion) and illustrated comparable drug release with that of marketed formulation (Etogesic®-ER 600 mg). The produced formulations revealed splendid reproducibility and stability under accelerated conditions.Conclusion: The judiciously planned fabrication of the matrix formulations possess the ability to decrease the frequency of drug administration to twice-daily along with minimizing the blood level fluctuations, which ultimately leads to enhanced patient compliance and better therapeutic regimens.


2014 ◽  
Vol 633-634 ◽  
pp. 562-566
Author(s):  
Yong Hui Wu ◽  
Deng Guang Yu ◽  
Qian Su ◽  
Cheng Lei Cai ◽  
Ji An Zhang ◽  
...  

The present study reports that a sustained release profile could be transferred into a biphasic drug release profile when a hydrophilic polymer was encapsulated into the medicated microparticles. The multiple component composite microparticles were fabricated using a single fluid electrospraying process to treat a co-dissolving solution consisting of a polymer matrix (shellac), an active ingredient (FA), and an additional hydrophilic polymer (poly vinyl pyrrolidone, PVP). FESEM results showed that the microparticles M1 consisting of shellac and FA had an average diameter of 1.27 ± 0.38 μm, whereas the microparticles M2 consisting of shellac, FA and PVP had an average diameter of 1.51 ± 0.34 μm. Both the two types of microparticles were essentially amorphous composites due to the favourable secondary interactions between the components, as demonstrated by ATR-FTIR tests. In vitro dissolution tests demonstrated that the addition of PVP in the microparticles M2 made them give a typical biphasic drug release profile, whereas the double-component microparticles provided a sustained release profile. This study shows a simple way for developing advanced drug delivery systems through tailoring the components of polymer excipients using electrospraying.


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