Design of polymeric microparticles for pH-responsive and time-sustained drug release

2013 ◽  
Vol 81 ◽  
pp. 177-186 ◽  
Author(s):  
Wenjie Liu ◽  
Cordelia Selomulya ◽  
Xiao Dong Chen
Keyword(s):  
Drug Release ◽  
Ph Responsive ◽  
Sustained Drug Release ◽  
Polymeric Microparticles

scholarly journals Design and Characterisation of pH-Responsive Photosensitiser-Loaded Nano-Transfersomes for Enhanced Photodynamic Therapy

Pharmaceutics ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 210
Author(s):  
Sooho Yeo ◽  
Il Yoon ◽  
Woo Kyoung Lee
Keyword(s):  
Photodynamic Therapy ◽  
Drug Release ◽  
Burst Release ◽  
Ph Responsive ◽  
Pheophorbide A ◽  
Sustained Drug Release ◽  
Non Invasive ◽  
Anti Cancer ◽  
Photodynamic Activity ◽  
The Mean

Photodynamic therapy (PDT) is a non-invasive and tumour-specific therapy. Photosensitizers (PSs) (essential ingredients in PDT) aggregate easily owing to their lipophilic properties. The aim of this study was to synthesise a PS (methyl pheophorbide a, MPa) and design a biocompatible lipid-based nanocarrier to improve its bioavailability and pharmacological effects. MPa-loaded nano-transfersomes were fabricated by sonication. The characteristics of synthesised PS and nano-transfersomes were assessed. The effects of PDT were evaluated by 1,3-diphenylisobenzofuran assay and by measuring photo-cytotoxicity against HeLa and A549 cell lines. The mean particle size and zeta potential for nano-transfersomes ranged from 95.84 to 267.53 nm and −19.53 to −45.08 mV, respectively. Nano-transfersomes exhibited sustained drug release for 48 h in a physiological environment (as against burst release in an acidic environment), which enables its use as a pH-responsive drug release system in PDT with enhanced photodynamic activity and reduced side effects. The formulations showed light cytotoxicity, but no dark toxicity, which meant that light irradiation resulted in anti-cancer effects. Additionally, formulations with the smallest size exhibited photodynamic activity to a larger extent than those with the highest loading capacity or free MPa. These results suggest that our MPa-loaded nano-transfersome system is a promising anti-cancer strategy for PDT.

scholarly journals Development of Functionalized Carbon Nano-Onions Reinforced Zein Protein Hydrogel Interfaces for Controlled Drug Release

Pharmaceutics ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 621 ◽  
Author(s):  
Narsimha Mamidi ◽  
Aldo González-Ortiz ◽  
Irasema Lopez Romo ◽  
Enrique V. Barrera
Keyword(s):  
Drug Release ◽  
Colloidal Stability ◽  
Controlled Drug Release ◽  
Acoustic Cavitation ◽  
Drug Transporter ◽  
Ph Responsive ◽  
Sustained Drug Release ◽  
In Vitro Degradation ◽  
Selective Delivery

In the current study, poly 4-mercaptophenyl methacrylate-carbon nano-onions (PMPMA-CNOs = f-CNOs) reinforced natural protein (zein) composites (zein/f-CNOs) are fabricated using the acoustic cavitation technique. The influence of f-CNOs inclusion on the microstructural properties, morphology, mechanical, cytocompatibility, in-vitro degradation, and swelling behavior of the hydrogels are studied. The tensile results showed that zein/f-CNOs hydrogels fabricated by the acoustic cavitation system exhibited good tensile strength (90.18 MPa), compared with the hydrogels fabricated by the traditional method and only microwave radiation method. It reveals the magnitude of physisorption and degree of colloidal stability of f-CNOs within the zein matrix under acoustic cavitation conditions. The swelling behaviors of hydrogels were also tested and improved results were noticed. The cytotoxicity of hydrogels was tested with osteoblast cells. The results showed good cell viability and cell growth. To explore the efficacy of hydrogels as drug transporters, 5-fluorouracil (5-FU) release was measured under gastric and intestinal pH environment. The results showed pH-responsive sustained drug release over 15 days of study, and pH 7.4 showed a more rapid drug release than pH 2.0 and 4.5. Nonetheless, all the results suggest that zein/f-CNOs hydrogel could be a potential pH-responsive drug transporter for a colon-selective delivery system.

Drug Sustained Release Multiple-Component Polymeric Microparticles Fabricated Using an Electrospray Process

2014 ◽  
Vol 937 ◽  
pp. 269-275 ◽  
Author(s):  
Xiao Yan Li ◽  
Deng Guang Yu ◽  
Fa Ping Jiang ◽  
Kong Jing Deng ◽  
Zhi Du ◽  
...  
Keyword(s):  
Drug Release ◽  
Sustained Release ◽  
Amorphous State ◽  
Release Time ◽  
Drug Release Profile ◽  
Sustained Drug Release ◽  
Electron Microscopic ◽  
Polymeric Microparticles ◽  
Multiple Component ◽  
Release Profiles

The present study investigates the preparation of ferulic acid (FA) sustained-release cellulose acetate (CA) microparticles, in which a third component, polyvinylpyrrolidone (PVP), was included into the microcomposites for an improved sustained drug release profile. An electrospraying process was exploited for the fabrication of multiple-component microparticles. Under an applied voltage of 18 kV, FA/PVP/CA composite microparticles were successfully generated. Field emission scanning electron microscopic observations demonstrated that these microparticles had an indented surface morphology with an average diameter of 1.71 ± 0.56 μm. The drug presented in the polymeric microparticles in an amorphous state due to the favorable secondary interactions among the components, as verified by the X-ray diffraction (XRD) patterns and attenuated total reflectance Fourier transform spectra. The triple-component microparticles could provide a fine sustained release profiles with full release completeness and small tailing-off release time period. The electrospraying process is a useful tool for developing sustained release microparticles and multiple-component co-existence in the microparticles can be taken to adjust the sustained drug release profiles.

Synthesis, Characterization and in-vitro drug release studies of a macromolecular prodrug of Didanosine.

2010 ◽  
Vol 2 (2) ◽  
Author(s):  
Neeraj Agrawal ◽  
M.J. Chandrasekar ◽  
U.V. Sara ◽  
Rohini A.
Keyword(s):  
Drug Release ◽  
Drug Level ◽  
Drug Release Profile ◽  
Sustained Drug Release ◽  
In Vitro Drug Release ◽  
Alkaline Environment ◽  
Stomach Acid ◽  
Release Studies ◽  
Macromolecular Prodrug

A macromolecular prodrug of didanosine (ddI) for oral administration was synthesized and evaluated for in-vitro drug release profile. Didanosine was first coupled to 2-hydroxy ethyl methacrylate (HEMA) through a succinic spacer to form HEMA-Suc-ddI monomeric conjugate which was subsequently polymerized to yield Poly(HEMA-Suc-ddI) conjugate. The structures of the synthesized compounds were characterized by FT-IR, Mass and 1H-NMR spectroscopy. The prodrug was subjected for in-vitro drug release studies in buffers of pH 1.2 and 7.4 mimicking the upper and lower GIT. The results showed that the drug release from the polymeric backbone takes place in a sustained manner over a period of 24 h and the amount of drug released was comparatively higher at pH 7.4 indicating that the drug release takes place predominantly at the alkaline environment of the lower GIT rather than at the acidic environment of the upper GIT. This pH dependent sustained drug release behavior of the prodrug may be capable of reducing the dose limiting toxicities by maintaining the plasma drug level within the therapeutic range and increasing t1/2 of ddI. Moreover, the bioavailability of the drug should be improved as the prodrug releases ddI predominantly in the alkaline environment which will reduce the degradation of ddI in the stomach acid.

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.

Nanostructures for pH-sensitive Drug Delivery and Magnetic Resonance Contrast Enhancement Systems

2018 ◽  
Vol 25 (25) ◽  
pp. 3036-3057 ◽  
Author(s):  
Xiao Sun ◽  
Guilong Zhang ◽  
Zhengyan Wu
Keyword(s):  
Drug Delivery ◽  
Magnetic Resonance ◽  
Drug Release ◽  
Contrast Enhancement ◽  
General Strategy ◽  
Ph Responsive ◽  
Physicochemical Changes ◽  
Magnetic Resonance Contrast ◽  
Resonance Contrast ◽  
Magnetic Resonance Contrast Enhancement

According to the differences of microenvironments between tumors and healthy tissues, if the anticancer drugs or magnetic resonance contrast agents (MRCAs) can be controlled to precisely match physiological needs at targeted tumor sites, it is expected to acquire better therapeutic efficacy and more accurate diagnosis. Over the decade, stimuli-responsive nanomaterials have been a research hotspot for cancer treatment and diagnosis because they show many excellent functions, such as in vivo imaging, combined targeting drug delivery and systemic controlled release, extended circulation time, etc. Among the various stimuli nanosystems, pH-stimuli mode is regarded as the most general strategy because of solid tumors acidosis. When exposed to weakly acidic tumor microenvironment, pH-responsive nanoplatforms can generate physicochemical changes for their structure and surface characteristics, causing drug release or contrast enhancement. In this review, we focused on the designs of various pH-responsive nanoplatforms and discussed the mechanisms of controlled drug release or switch on-off in MRCAs. This review also discussed the efficacy of cellular internalization for these nanoplatforms via endocytosis of acidic tumor cell. Meanwhile, nanoplatforms response to acidic intracellular pH (such as endosome, lysosome) are discussed, along with approaches for improving drug release performance and magnetic resonance contrast enhancement. A greater understanding of these pH-responsive nanoplatforms will help design more efficient nanomedicine to address the challenges encountered in conventional diagnosis and chemotherapy.

Development and Optimization of Sustained Release Moxifloxacin Hydrochloride Loaded Nanoemulsion for Ophthalmic Drug Delivery: A 32 Factorial Design Approach

2020 ◽  
Vol 12 ◽  
Author(s):  
Sagar R. Pardeshi ◽  
Harshal A. Mistari ◽  
Rakhi S. Jain ◽  
Pankaj R. Pardeshi ◽  
Rahul L. Rajput ◽  
...  
Keyword(s):  
Drug Release ◽  
Sustained Release ◽  
Factorial Design ◽  
Water Solubility ◽  
Tween 80 ◽  
Drug Release Profile ◽  
Sustained Drug Release ◽  
Bacterial Conjunctivitis ◽  
Promising Alternative

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.

Computational studies on self-assembled paclitaxel structures: Templates for hierarchical block copolymer assemblies and sustained drug release

Biomaterials ◽  
2009 ◽  
Vol 30 (33) ◽  
pp. 6556-6563 ◽  
Author(s):  
Xin D. Guo ◽  
Jeremy P.K. Tan ◽  
Sung H. Kim ◽  
Li J. Zhang ◽  
Ying Zhang ◽  
...  
Keyword(s):  
Block Copolymer ◽  
Drug Release ◽  
Computational Studies ◽  
Sustained Drug Release ◽  
Self Assembled

scholarly journals The Impact of Gelatin on the Pharmaceutical Characteristics of Fucoidan Microspheres with Posaconazole

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4087
Author(s):  
Marta Szekalska ◽  
Aleksandra Citkowska ◽  
Magdalena Wróblewska ◽  
Katarzyna Winnicka
Keyword(s):  
Antifungal Activity ◽  
Drug Release ◽  
Spray Drying ◽  
Fungal Infections ◽  
Drug Loading ◽  
High Surface ◽  
Vaginal Fluid ◽  
Sustained Drug Release ◽  
Candida Spp ◽  
The Impact

Fungal infections and invasive mycoses, despite the continuous medicine progress, are an important globally therapeutic problem. Multicompartment dosage formulations (e.g., microparticles) ensure a short drug diffusion way and high surface area of drug release, which as a consequence can provide improvement of therapeutic efficiency compared to the traditional drug dosage forms. As fucoidan is promising component with wide biological activity per se, the aim of this study was to prepare fucospheres (fucoidan microparticles) and fucoidan/gelatin microparticles with posaconazole using the one-step spray-drying technique. Pharmaceutical properties of designed fucospheres and the impact of the gelatin addition on their characteristics were evaluated. An important stage of this research was in vitro evaluation of antifungal activity of developed microparticles using different Candida species. It was observed that gelatin presence in microparticles significantly improved swelling capacity and mucoadhesiveness, and provided a sustained POS release. Furthermore, it was shown that gelatin addition enhanced antifungal activity of microparticles against tested Candida spp. strains. Microparticles formulation GF6, prepared by the spray drying of 20% fucoidan, 5% gelatin and 10% Posaconazole, were characterized by optimal mucoadhesive properties, high drug loading and the most sustained drug release (after 8 h 65.34 ± 4.10% and 33.81 ± 5.58% of posaconazole was dissolved in simulated vaginal fluid pH 4.2 or 0.1 M HCl pH 1.2, respectively).

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