scholarly journals Degradation Behavior of Polymers Used as Coating Materials for Drug Delivery—A Basic Review

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1272
Author(s):  
Anita Ioana Visan ◽  
Gianina Popescu-Pelin ◽  
Gabriel Socol
Keyword(s):  
Drug Delivery ◽  
Degradation Mechanism ◽  
Degradation Behavior ◽  
Polymeric Coatings ◽  
Degradation Mechanisms ◽  
Coating Materials ◽  
Factors Affecting ◽  
Existing Problems ◽  
Future Performance ◽  
Measuring Techniques

The purpose of the work was to emphasize the main differences and similarities in the degradation mechanisms in the case of polymeric coatings compared with the bulk ones. Combined with the current background, this work reviews the properties of commonly utilized degradable polymers in drug delivery, the factors affecting degradation mechanism, testing methods while offering a retrospective on the evolution of the controlled release of biodegradable polymeric coatings. A literature survey on stability and degradation of different polymeric coatings, which were thoroughly evaluated by different techniques, e.g., polymer mass loss measurements, surface, structural and chemical analysis, was completed. Moreover, we analyzed some shortcomings of the degradation behavior of biopolymers in form of coatings and briefly proposed some solving directions to the main existing problems (e.g., improving measuring techniques resolution, elucidation of complete mathematical analysis of the different degradation mechanisms). Deep studies are still necessary on the dynamic changes which occur to biodegradable polymeric coatings which can help to envisage the future performance of synthesized films designed to be used as medical devices with application in drug delivery.

An overview of Osmotic Drug Delivery System: An update review

2017 ◽  
Vol 6 (7) ◽  
pp. 5426 ◽  
Author(s):  
Hiren J. Patel ◽  
Vaishnavi P. Parikh
Keyword(s):  
Drug Delivery ◽  
Drug Delivery Systems ◽  
Life Cycle Management ◽  
Delivery Systems ◽  
Osmotic Pump ◽  
Factors Affecting ◽  
Advantages And Disadvantages ◽  
New Chemical Entities ◽  
History Of ◽  
Novel Drug

The pharmaceutical industry has faced several marked challenges in order to bring new chemical entities (NCEs) into the market over the past few decades. Various novel drug delivery approaches have been used as a part of life cycle management from which Osmotic drug delivery systems look the most promising one. After discussing the history of osmotic pump development, this article looks at the principles, advantages and disadvantages of osmotic drug delivery systems. Then, the basic components of osmotic pump and factors affecting the design of oral osmotic drug delivery systems are discussed in detail. In the later part of the manuscript, various types of osmotic pumps available in the market and evaluation methods for osmotic drug delivery systems are discussed in detail.

scholarly journals Degradation Mechanism of Porous Metal-Organic Frameworks by In Situ Atomic Force Microscopy

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 722
Author(s):  
Ioanna Christodoulou ◽  
Tom Bourguignon ◽  
Xue Li ◽  
Gilles Patriarche ◽  
Christian Serre ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Degradation Mechanism ◽  
Metal Organic Frameworks ◽  
Porous Metal ◽  
Force Microscopy ◽  
Atomic Force ◽  
Metal Organic ◽  
The Media ◽  
Ph Conditions

In recent years, Metal-Organic Frameworks (MOFs) have attracted a growing interest for biomedical applications. The design of MOFs should take into consideration the subtle balance between stability and biodegradability. However, only few studies have focused on the MOFs’ stability in physiological media and their degradation mechanism. Here, we investigate the degradation of mesoporous iron (III) carboxylate MOFs, which are among the most employed MOFs for drug delivery, by a set of complementary methods. In situ AFM allowed monitoring with nanoscale resolution the morphological, dimensional, and mechanical properties of a series of MOFs in phosphate buffer saline and in real time. Depending on the synthetic route, the external surface presented either well-defined crystalline planes or initial defects, which influenced the degradation mechanism of the particles. Moreover, MOF stability was investigated under different pH conditions, from acidic to neutral. Interestingly, despite pronounced erosion, especially at neutral pH, the dimensions of the crystals were unchanged. It was revealed that the external surfaces of MOF crystals rapidly respond to in situ changes of the composition of the media they are in contact with. These observations are of a crucial importance for the design of nanosized MOFs for drug delivery applications.

The impact of adaptability on the competitiveness of non-State pension funds

2021 ◽  
Vol 27 (11) ◽  
pp. 2606-2636
Author(s):  
Ekaterina S. YAROVAYA
Keyword(s):  
Pension Fund ◽  
Pension Funds ◽  
High Variability ◽  
Current Time ◽  
Factors Affecting ◽  
Existing Problems ◽  
State Pension ◽  
The Impact ◽  
State Pension Funds

Subject. This article deals with the analysis of competitiveness, which is an important component of the strategic management of a non-State pension fund. Objectives. The article aims to study the existing approaches to the analysis of competitiveness, determine the role of the indicator of adaptability of competitiveness of non-State pension funds in conditions of high variability of the external environment, and formulate recommendations for drawing up criteria for the enterprise competitiveness taking into account the specifics of the activities of the funds. Methods. For the study, I used analysis, and the systems, and structural and functional approaches. Results. The article defines and classifies the factors affecting the competitiveness of non-State pension funds in modern market conditions. It substantiates the influence of the indicator of adaptability on the competitiveness of non-State pension funds. The article also proposes an approach to ranking this indicator, which can be applied regardless of the chosen method for assessing the competitiveness of non-State pension funds. Conclusions. The article concludes that the testing of the assessment of the non-State pension fund competitiveness using the author-proposed adaptability indicator helps determine the level of non-State pension fund competitiveness at the current time, track the changes, and identify the existing problems, the causes of their occurrence, and thereby ensure the conditions under which the non-State pension fund has the opportunity to promptly respond and adapt to external changes thus ensuring its stability in the market.

scholarly journals Green synthesis of the innovative super paramagnetic nanoparticles from the leaves extract of Fraxinus chinensis Roxb and their application for the decolourisation of toxic dyes

2019 ◽  
Vol 8 (1) ◽  
pp. 256-271 ◽  
Author(s):  
Imran Ali ◽  
Changsheng Peng ◽  
Dichu Lin ◽  
Iffat Naz
Keyword(s):  
Environmental Remediation ◽  
Degradation Mechanism ◽  
Pseudo First Order Reaction ◽  
Solution Ph ◽  
Factors Affecting ◽  
Toxic Dyes ◽  
Degradation Of Dyes ◽  
Stability Structure ◽  
Ft Ir ◽  
Fraxinus Chinensis

Abstract The leaves extract of Fraxinus chinensis Roxb was used for the synthesis of the innovative phytogenic magnetic nanoparticles (PMNPs) without adding toxic surfactants. The formation, morphology, elemental composition, size, thermal stability, structure and magnetic properties of these PMNPs were examined by UV-visible spectrophotometry, FT-IR, XRD, SEM, EDX, TEM, VSM, XPS, BET and TGA. The reactivity of the obtained PMNPs against decolourising toxic dyes, namely, malachite green (MG), crystal violet (CV) and methylene blue (MB), were investigated by UV-vis spectrophotometry. Further, the factors affecting the removal of dyes, including solution pH, adsorbent dosages, initial concentration of dyes, reaction temperature and contact time, were also investigated. The results revealed the decolourisation of 99.12% of MG and 98.23% of CV within 60 min, and 97.52% of MB within 200 min by the PMNPs using dyes concentration of 25 mg/l at pH 6.5 and 298.15 K. The kinetics outcome indicated that the degradation of dyes matched well to the pseudo first-order reaction kinetics model. Furthermore, the probable degradation mechanism of dyes by the PMNPs, including the adsorption of cationic dye molecules onto the negatively charged surface of adsorbent and the oxidation of the Fe° in the solution, were discussed. Thus, the PMNPs can be produced by the bulk and have great potential to be employed for biomedical/environmental remediation.

Pharmaceutical Innovation in the United States: Factors Affecting Future Performance

1993 ◽  
Vol 9 (2) ◽  
pp. 167-173 ◽  
Author(s):  
Michael R. Pollard
Keyword(s):  
United States ◽  
Pharmaceutical Industry ◽  
Research And Development ◽  
Cost Containment ◽  
The United States ◽  
Private Companies ◽  
Factors Affecting ◽  
The Past ◽  
Future Performance ◽  
Regulatory Strategy

AbstractFueled by high returns on its investments, the pharmaceutical industry in the United States has flourished for the past 50 years. The regulatory strategy of demanding stringent testing then allowing market-based pricing has allowed private companies to fund ambitious research and development activities with the assurance that these investments will be recovered. However, aggressive managed-care cost-containment strategies threaten the companies' ability to recoup research and development expenses and may affect their willingness to invest in future innovative research.

Electoral Performance by Post-Rebel Parties

2018 ◽  
Vol 54 (3) ◽  
pp. 415-453 ◽  
Author(s):  
Carrie Manning ◽  
Ian Smith
Keyword(s):  
Legislative Elections ◽  
Full Data ◽  
Data Set ◽  
Factors Affecting ◽  
Future Performance ◽  
Organizational Experience ◽  
Varying Length ◽  
New Research ◽  
Electoral Performance ◽  
Positive Effect

This article explores the factors affecting post-rebel party electoral performance. We present new research tracking the participation of these groups in national legislative elections from 1990 to 2016. Our full data set covers 77 parties and 286 elections in 37 countries. It includes parties formed after conflicts of varying length and intensity, with different incompatibilities, in every region of the world, and in countries with disparate political histories. Our analysis suggests that post-rebel parties’ early electoral performance strongly affects future performance, and that competition – crowd-out by older rival parties – and pre-war organizational experience in politics have a significant positive effect, particularly for those parties that are consistently winning more than about 10 per cent of seats. But especially for parties that consistently win very low seat shares, organizational characteristics yield increasingly to environmental factors, most importantly the presence of rival parties and the barriers to representation presented by electoral rules.

Degradation behavior and degradation mechanism of bridged-grain polycrystalline silicon thin film transistors under AC gate bias stress

2017 ◽  
Vol 32 (2) ◽  
pp. 91-96
Author(s):  
张猛 ZHANG Meng ◽  
夏之荷 XIA Zhi-he ◽  
周玮 ZHOU Wei ◽  
陈荣盛 CHEN Rong-sheng ◽  
王文 WONG Man ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Film Transistors ◽  
Polycrystalline Silicon ◽  
Degradation Mechanism ◽  
Gate Bias ◽  
Degradation Behavior ◽  
Silicon Thin Film ◽  
Bias Stress ◽  
Gate Bias Stress

scholarly journals Stability of Engineered Micro or Nanobubbles for Biomedical Applications

Pharmaceutics ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 1089
Author(s):  
Beomjin Park ◽  
Semi Yoon ◽  
Yonghyun Choi ◽  
Jaehee Jang ◽  
Soomin Park ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Biomedical Applications ◽  
Ultrasonic Field ◽  
Nanometer Scale ◽  
Factors Affecting ◽  
The Core ◽  
Bubble Structure ◽  
The Stability ◽  
The Relationship

A micro/nanobubble (MNB) refers to a bubble structure sized in a micrometer or nanometer scale, in which the core is separated from the external environment and is normally made of gas. Recently, it has been confirmed that MNBs can be widely used in angiography, drug delivery, and treatment. Thus, MNBs are attracting attention as they are capable of constructing a new contrast agent or drug delivery system. Additionally, in order to effectively use an MNB, the method of securing its stability is also being studied. This review highlights the factors affecting the stability of an MNB and the stability of the MNB within the ultrasonic field. It also discusses the relationship between the stability of the bubble and its applicability in vivo.

Sign in / Sign up

Export Citation Format

Share Document