scholarly journals Smart Microneedles with Porous Polymer Coatings for pH-Responsive Drug Delivery

Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1834 ◽  
Author(s):  
Ullah ◽  
Khan ◽  
Choi ◽  
Kim
Keyword(s):  
Drug Delivery ◽  
Controlled Release ◽  
Drug Release ◽  
Sodium Bicarbonate ◽  
Porous Polymer ◽  
Polymer Layer ◽  
Ph Responsive ◽  
Acidic Microenvironment ◽  
Model Drug

: This work demonstrates a simple approach for coating a porous polymer layer on stainless-steel (SS) microneedles characterized by a pH-responsive formulation for self-regulated drug delivery. For many drug-delivery applications, the release of therapeutic agents in an acidic microenvironment is desirable. Acid-sensitive polymers and hydrogels were extensively explored, but easily prepared polymeric microcarriers that combine acid sensitivity and biodegradability are rare. Here, we describe a simple and robust method of coating a porous polymer layer on SS microneedles (MNs) that release a model drug (lidocaine) in a pH-responsive fashion. It was constructed by packing the model drug and a pH-sensitive component (sodium bicarbonate) into the pores of the polymer layer. When this acid-sensitive formulation was exposed to the acidic microenvironment, the consequent reaction of protons (H+) with sodium bicarbonate (NaHCO3) yielded CO2. This effect generated pressure inside the pores of the coating and ruptured the thin polymer membrane, thereby releasing the encapsulated drug. Scanning electron micrographs showed that the pH-sensitive porous polymer-coated MNs exposed to phosphate-buffered saline (PBS) at pH 7.4 were characterized by closed pores. However, MNs exposed to PBS at pH 5.5 consisted of open pores and the thin membrane burst. The in vitro studies demonstrated the pH sensitivity of the drug release from porous polymer-coated MNs. Negligible release was observed for MNs in receiving media at pH 7.4. In contrast, significant release occurred when the MNs were exposed to acidic conditions (pH 5.5). Additionally, comparable results were obtained for drug release in vitro in porcine skin and in PBS. This revealed that our developed pH-responsive porous polymer-coated MNs could potentially be used for the controlled release of drug formulations in an acidic environment. Moreover, the stimuli-responsive drug carriers will enable on-demand controlled release profiles that may enhance therapeutic effectiveness and reduce systemic toxicity.

Synthesis of Chitosan-Polyvinyl Alcohol Copolymers for Smart Drug Delivery Application

2017 ◽  
Vol 25 (3) ◽  
pp. 241-246 ◽  
Author(s):  
Neha Mulchandani ◽  
Nimish Shah ◽  
Tejal Mehta
Keyword(s):  
Drug Delivery ◽  
Drug Release ◽  
Polyvinyl Alcohol ◽  
Morphological Changes ◽  
Crosslinking Agent ◽  
Ph Responsive ◽  
Thermal Transitions ◽  
Scanning Calorimetry ◽  
Model Drug

Chitosan is a natural polymer obtained from exoskeletons of crustaceans and polyvinyl alcohol (PVA) is a synthetic polymer which has excellent film forming ability along with non-toxic nature. The current work focuses on synthesizing a smart polymer by copolymerization of natural and synthetic polymers and exploring its applications in drug delivery. The copolymers were blended in different ratios and were synthesized using ammonium ceric nitrate as initiator and glutaraldehyde as a crosslinking agent which were converted to films by casting method. Amoxicillin, as a model drug was incorporated to the copolymerized films to study the in-vitro drug release. The films obtained were evaluated by varying the pH to study the pH responsive nature of films. Drug release studies were performed to obtain the release profile of drug; water uptake capacity of the copolymerized film were measured to determine the swelling behaviour of the films. The films were further characterized using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Differential Scanning Calorimetry (DSC) to identify the structural and morphological changes along with thermal transitions. The results indicate that the synthesized copolymers are pH responsive in nature having great potential for application in controlled and targeted drug delivery.

scholarly journals Encapsulation of Liposomes within pH Responsive Microspheres for Oral Colonic Drug Delivery

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
M. J. Barea ◽  
M. J. Jenkins ◽  
Y. S. Lee ◽  
P. Johnson ◽  
R. H. Bridson
Keyword(s):  
Drug Delivery ◽  
Small Intestine ◽  
Drug Release ◽  
Ph Responsive ◽  
Site Specific ◽  
Colonic Drug Delivery ◽  
Eudragit S100 ◽  
Release Studies ◽  
Model Drug

A novel liposome-in-microsphere (LIM) formulation has been created comprising drug-loaded liposomes within pH responsive Eudragit S100 microspheres. The liposomes contained the model drug 5-ASA and were coated with chitosan in order to protect them during encapsulation within the microspheres and to improve site-specific release characteristics.In vitrodrug release studies showed that LIMs prevented drug release within simulated stomach and small intestine conditions with subsequent drug release occurring in large intestine conditions. The formulation therefore has potential for oral colonic drug delivery.

Preparation and Characterization of Biopolymeric Nanoparticles as Drug Delivery Vehicles

2017 ◽  
pp. 225-246
Author(s):  
Sai S. Sagiri ◽  
Suraj K. Nayak ◽  
S. Lakshmi ◽  
Kunal Pal
Keyword(s):  
Drug Delivery ◽  
Salicylic Acid ◽  
Drug Release ◽  
Chitosan Nanoparticles ◽  
Xrd Analysis ◽  
Gelatin Nanoparticles ◽  
Drug Delivery Vehicles ◽  
Model Drug ◽  
Bioactive Agents

In recent years, the use of biopolymeric nanoparticles as vehicles for drug delivery has increased exponentially. In the present study, chitosan and gelatin nanoparticles were prepared by ionic gelation and desolvation methods, respectively. Salicylic acid was used as the model drug. The nanoparticles were characterized using SEM, XRD analysis and FTIR spectrophotometric studies. In vitro drug release experiments were carried out to understand the mechanism of drug release. SEM micrographs showed the formation of spherical nanoparticles. XRD studies indicated a higher crystalline nature of the chitosan nanoparticles as compared to the gelatin nanoparticles. FTIR studies indicated the presence of salicylic acid within the drug- loaded nanoparticles. Drug release studies indicated that the developed nanoparticles may be used as carriers for various bioactive agents.

scholarly journals Formulation and in-vitro evaluation of ciprofloxacin HCL floating matrix tablets

2020 ◽  
Vol 2 (1) ◽  
pp. 01-06
Author(s):  
Dhulipalla Mounika ◽  
I. Deepika Reddy ◽  
K. Sai Chandralekha ◽  
Kapu Harika ◽  
Ramarao Nadendla ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Controlled Release ◽  
Drug Release ◽  
Matrix Tablets ◽  
Fickian Diffusion ◽  
In Vitro Dissolution ◽  
Oral Drug ◽  
Prolonged Release ◽  
Evaluation Parameters

Oral drug delivery is the most widely utilized route of administration among all the routes that have been explored for systemic delivery of drugs via pharmaceutical products of different dosage form. Oral route is considered most natural, uncomplicated, convenient and safe due to its ease of administration, patient acceptance and cost-effective manufacturing process. Gastroretentive drug delivery system was developed in pharmacy field and drug retention for a prolonged time has been achieved. The goal of this study was to formulate and in-vitro evaluate Ciprofloxacin HCl controlled release matrix floating tablets. Ciprofloxacin HCl floating matrix tablets were prepared by wet granulation method using two polymers such as HPMC K100M (hydrophilic polymer) and HPMC K15M. All the Evaluation parameters were within the acceptable limits. FTIR spectral analysis showed that there was no interaction between the drug and polymers. In-vitro dissolution study was carried out using USP dissolution test apparatus (paddle type) at 50 rpm. The test was carried out at 37 ± 0.5 0C in 900ml of the 0.1 N HCl buffer as the medium for eight hours. HPMC K100M shows a prolonged release when compared to HPMC K15M. These findings indicated that HPMC K100M can be used to develop novel gastroretentive controlled release drug delivery systems with the double advantage of controlled drug release at GIT pH. On comparing the major criteria in evaluation such as preformulation and in vitro drug release characteristics, the formulation F8 was selected as the best formulation, as it showed the drug content as 99±0.4% and swelling index ratio was 107.14, and in-vitro drug released 61.31±0.65% up to 8 hours. Results indicated that controlled Ciprofloxacin HCl release was directly proportional to the concentration of HPMC K100M and the release of drug followed non-Fickian diffusion. Based on all the above evaluation parameters it was concluded that the formulation batch F8 was found to be best formulation among the formulations F1 to F8 were prepared.

Preparation and in-vitro evaluation of β-CD/HA nanocomposite as a potential carrier for hydrophobic drugs

2021 ◽  
pp. 088532822110122
Author(s):  
Esmaeil Salimi ◽  
Mohammad Jafar Molaei
Keyword(s):  
Drug Delivery ◽  
Drug Release ◽  
Chemical Bonding ◽  
Ftir Analysis ◽  
Hydrophobic Compounds ◽  
Vis Spectroscopy ◽  
Insoluble Drugs ◽  
Model Drug ◽  
Xrd Patterns

This study aimed to provide a new drug delivery system for hydrophobic compounds. Dexamethasone (DEX) was employed as a hydrophobic model drug, which incorporated into the network of hydroxyapatite (HA)/Cyclodextrin (β-CD) nanocomposite. Phase analysis, chemical bonding, morphology, and drug release was evaluated using XRD, FTIR, FESEM, and UV-vis spectroscopy, respectively. XRD patterns showed the formation of the crystalline structure and FTIR analysis showed the chemical bonding between organic and inorganic phases. FESEM images accompanied by EDX analysis confirmed the presence of HA nano-flakes. Release of DEX loaded β-CD/HA was measured to be around 4.6% and 18.7% in pH5.3 and pH 7.4, respectively. In conclusion, the prepared system could be a potential pH sensitive carrier for sustainable release of water-insoluble drugs.

scholarly journals Synergistic Effect of Ultrasound and Polyethylene Glycol on the Mechanism of the Controlled Drug Release from Polylactide Matrices

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 880
Author(s):  
Wenting Bao ◽  
Xianlong Zhang ◽  
Hong Wu ◽  
Rong Chen ◽  
Shaoyun Guo
Keyword(s):  
Polyethylene Glycol ◽  
Controlled Release ◽  
Drug Release ◽  
Synergistic Effect ◽  
In Vitro Release ◽  
Structure And Properties ◽  
Melt Extrusion ◽  
Model Drug ◽  
Vitro Release

In this paper, the synergistic effect of ultrasound and polyethylene glycol (PEG) on the controlled release of a water soluble drug from polylactide (PLA) matrices was studied. When ultrasound was used following the hot melt extrusion (HME) of the PLA/model drug release system, the release of the model drug (Methylene Blue (MB)) from the PLA when immersed in phosphate buffered saline (PBS) was affected by the variation of the parameters of ultrasound. It was found that no more than 2% PLA dissolved during the in-vitro release study, and the release of the MB from the PLA was diffusion controlled and fit well with the Higuchi diffusion model. Polyethylene glycol (PEG), which has high hydrophilicity and rapid dissolution speed, was blended with the PLA during the melt extrusion to enhance the release of the MB. The analysis of the structure and properties of the in-vitro release tablets of PLA/PEG/MB indicated that the ultrasound could improve the dispersion of MB in the PLA/PEG blends and it could also change the structure and properties of the PLA/PEG blends. Due to the dissolution of the PEG in PBS, the release of the MB from the PLA/PEG drug carrier was a combination of diffusion and erosion controlled release. Thus a new mechanism combining of diffusion and erosion models and modified kinetics model was proposed to explain the release behavior.

scholarly journals pH-Responsive TiO2 Nanotube Drug Delivery System Based on Iron Coordination

2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Yan Liu ◽  
Chunling Xie ◽  
Fengfen Zhang ◽  
Xiufeng Xiao
Keyword(s):  
Drug Delivery ◽  
Drug Release ◽  
Drug Delivery System ◽  
Delivery System ◽  
Coordination Bond ◽  
Electrochemical Anodization ◽  
Ph Responsive ◽  
Step Procedure ◽  
Potential Applications

Nanostructured materials play a fundamental role in orthopedic research owing to their outstanding properties and excellent biocompatibility. Titania nanotube (TNT) arrays engineered by electrochemical anodization process have been extensively explored and used as effective carriers for controlled drug delivery. In this study, we proposed a drug delivery system based on coordination bond. Iron (III), Fe3+, on the nanotube surface can effectively bind to alendronate sodium (NaAL), a drug for the treatment of osteoporosis, through coordination bonds, which can be formed or broken through the change of pH, and thus can be controlled by pH. The pH-responsive system was prepared by three-step procedure: (i) fabrication of TNTs by electrochemical anodization, (ii) modification of amino groups on the surface of nanotubes by hydrothermal method, and (iii) amino-functionalized nanotubes by Fe3+ solution soak. The Fe-modified TNTs not only allowed alendronate-loading content of up to 50.2% by weight, which is significantly higher than most drug delivery systems previously reported, but also delayed and prolonged drug release. Moreover, in vitro drug release experiments demonstrated that coordination bond-based TNT system may have great potential applications in clinical use.

Preparation and Characterization of Biopolymeric Nanoparticles as Drug Delivery Vehicles

2021 ◽  
pp. 1659-1680
Author(s):  
Sai S. Sagiri ◽  
Suraj K. Nayak ◽  
S. Lakshmi ◽  
Kunal Pal
Keyword(s):  
Drug Delivery ◽  
Salicylic Acid ◽  
Drug Release ◽  
Chitosan Nanoparticles ◽  
Xrd Analysis ◽  
Gelatin Nanoparticles ◽  
Drug Delivery Vehicles ◽  
Model Drug ◽  
Bioactive Agents

In recent years, the use of biopolymeric nanoparticles as vehicles for drug delivery has increased exponentially. In the present study, chitosan and gelatin nanoparticles were prepared by ionic gelation and desolvation methods, respectively. Salicylic acid was used as the model drug. The nanoparticles were characterized using SEM, XRD analysis and FTIR spectrophotometric studies. In vitro drug release experiments were carried out to understand the mechanism of drug release. SEM micrographs showed the formation of spherical nanoparticles. XRD studies indicated a higher crystalline nature of the chitosan nanoparticles as compared to the gelatin nanoparticles. FTIR studies indicated the presence of salicylic acid within the drug- loaded nanoparticles. Drug release studies indicated that the developed nanoparticles may be used as carriers for various bioactive agents.

Synthesis and Drug Release from a PH/Temperature Sensitive Bead of Poly(N-Acryloylglycinate) and Alginate

2011 ◽  
Vol 117-119 ◽  
pp. 1227-1230
Author(s):  
Kui Lin Deng ◽  
Ting Gao ◽  
Yu Bo Gou ◽  
Wei Wang ◽  
Peng Fei Zhang ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Drug Release ◽  
Temperature Sensitive ◽  
Polymer Content ◽  
In Vitro Drug Release ◽  
Buffer Solutions ◽  
Drug Delivery Carrier ◽  
Different Temperatures ◽  
Model Drug

In this paper, a new pH/temperature sensitive beads with core-shelled structure, composed of sodium alginate and poly(N-acryloylglycinate), were prepared using as drug delivery carrier. Selecting indomethacin as a model drug, in vitro drug release behaviors were investigated at different temperatures, phosphate buffer solutions (PBS) and polymer content. At pH=2.1, the release amount of indomethacin loaded in the beads was only 2.46% while this value approached to 95.23% in pH=7.4 PBS. In addition, the release rate of indomethacin at 37°C is much higher than at 18°C.

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