New materials and systems for drug delivery and targeting

The anticipated benefits of nano-formulations for drug delivery are well known: for nanomedicines to achieve this potential, new materials are required with predictive and tuneable properties. Excretion of excipients following delivery is advantageous to minimise the possibility of adverse effects; biodegradability to non-toxic products is therefore desirable. With this in mind, we aim to develop tuneable hybrid lipid-block copolymer vesicle formulations where the hydrophilic polymer block is polyethylene glycol (PEG), which has accepted biocompatibility, and the hydrophobic block of the polymer is biodegradable: polycaprolactone (PCL) or polylactide (PLA). We investigate five different block copolymers for the formation of 1:1 phospholipid:polymer hybrid vesicles, compare their properties to the appropriate unitary liposome (POPC) and polymersome systems and assess their potential for future development as nanomedicine formulations. The PEG-PCL polymers under investigation do not form polymersomes and exhibit poor colloidal and/or encapsulation stability in hybrid formulations with lipids. The properties of PEG-PLA hybrid vesicles are found to be more encouraging: they have much enhanced passive loading of a hydrophilic small molecule (carboxyfluorescein) compared to their respective polymersomes and exhibit more favourable release kinetics in the presence of serum compared to the liposome. Significantly, burst release from hybrid vesicles can be substantially reduced by making the polymer components of the hybrid vesicle a mixture containing 10 mol% of PEG16-PLA25 that is intermediate in size between the phospholipid and larger PEG45-PLA54 components. We conclude that hybrid lipid/PEG-PLA vesicles warrant further assessment and development as candidate drug delivery systems.

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Biodegradable Hybrid Block Copolymer – Lipid Vesicles as Potential Drug Delivery Systems

10.26434/chemrxiv.8049938 ◽

2019 ◽

Author(s):

Sanobar Khan ◽

James McCabe ◽

Kathryn Hill ◽

Paul Beales

Keyword(s):

Drug Delivery ◽

Block Copolymer ◽

Drug Delivery Systems ◽

Release Kinetics ◽

Lipid Vesicles ◽

Delivery Systems ◽

Burst Release ◽

New Materials ◽

Candidate Drug ◽

Polymer Block

The anticipated benefits of nano-formulations for drug delivery are well known: for nanomedicines to achieve this potential, new materials are required with predictive and tuneable properties. Excretion of excipients following delivery is advantageous to minimise the possibility of adverse effects; biodegradability to non-toxic products is therefore desirable. With this in mind, we aim to develop tuneable hybrid lipid-block copolymer vesicle formulations where the hydrophilic polymer block is polyethylene glycol (PEG), which has accepted biocompatibility, and the hydrophobic block of the polymer is biodegradable: polycaprolactone (PCL) or polylactide (PLA). We investigate five different block copolymers for the formation of 1:1 phospholipid:polymer hybrid vesicles, compare their properties to the appropriate unitary liposome (POPC) and polymersome systems and assess their potential for future development as nanomedicine formulations. The PEG-PCL polymers under investigation do not form polymersomes and exhibit poor colloidal and/or encapsulation stability in hybrid formulations with lipids. The properties of PEG-PLA hybrid vesicles are found to be more encouraging: they have much enhanced passive loading of a hydrophilic small molecule (carboxyfluorescein) compared to their respective polymersomes and exhibit more favourable release kinetics in the presence of serum compared to the liposome. Significantly, burst release from hybrid vesicles can be substantially reduced by making the polymer components of the hybrid vesicle a mixture containing 10 mol% of PEG16-PLA25 that is intermediate in size between the phospholipid and larger PEG45-PLA54 components. We conclude that hybrid lipid/PEG-PLA vesicles warrant further assessment and development as candidate drug delivery systems.

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Repelling and ordering: the influence of poly(ethylene glycol) on protein adsorption

Physical Chemistry Chemical Physics ◽

10.1039/c7cp05445a ◽

2017 ◽

Vol 19 (41) ◽

pp. 28182-28188 ◽

Cited By ~ 18

Author(s):

Christoph Bernhard ◽

Steven J. Roeters ◽

Johannes Franz ◽

Tobias Weidner ◽

Mischa Bonn ◽

...

Keyword(s):

Drug Delivery ◽

Ethylene Glycol ◽

Protein Adsorption ◽

Interfacial Properties ◽

Fine Tuning ◽

New Materials ◽

Poly Ethylene Glycol ◽

Poly Ethylene

Development of new materials for drug delivery and biosensing requires the fine-tuning of interfacial properties.

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Surface modified cellulose nanomaterials: a source of non-spherical nanoparticles for drug delivery

Materials Horizons ◽

10.1039/c9mh01727e ◽

2020 ◽

Vol 7 (7) ◽

pp. 1727-1758 ◽

Cited By ~ 4

Author(s):

Yee Yee Khine ◽

Martina H. Stenzel

Keyword(s):

Drug Delivery ◽

Building Block ◽

Surface Modifications ◽

Drug Carriers ◽

Spherical Nanoparticles ◽

New Materials ◽

Cellulose Nanomaterials ◽

Surface Modified ◽

Modified Cellulose

Cellulose nanomaterials, often called nanocellulose, have created a lot of buzz as a renewable building block for new materials. In this review, the steps necessary to generate soluble nanocellulose-based drug carriers are discussed, which includes surface modifications and toxicity.

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The Application of Nanomaterials in Cardiovascular Diseases: A Review on Drugs and Devices

Journal of Pharmacy & Pharmaceutical Sciences ◽

10.18433/jpps30456 ◽

2019 ◽

Vol 22 ◽

pp. 501-515

Author(s):

Solmaz Maleki Dizaj ◽

Abbas Afrasiabi Rad ◽

Naser Safaei ◽

Sara Salatin ◽

Elham Ahmadian ◽

...

Keyword(s):

Drug Delivery ◽

Cardiovascular Diseases ◽

Causes Of Death ◽

Implantable Devices ◽

New Materials ◽

Safe Treatment ◽

Recent Advances

Cardiovascular diseases (CVDs) are still one of the main causes of death. In recent years, nanotechnology has offered new materials and strategies for more effective and safe treatment as well as diagnosis of CVDs. This review highlights the recent advances in nanotechnology applications in CVD therapy. The manipulation and the production of biomedical implantable devices based on nanomedicine approaches as well as drug delivery concepts for diagnosing and treatment of CVDs are discussed in this paper.

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The Effect of Ethanol on Gelation, Nanoscopic, and Macroscopic Properties of Serum Albumin Hydrogels

Molecules ◽

10.3390/molecules25081927 ◽

2020 ◽

Vol 25 (8) ◽

pp. 1927

Author(s):

Seyed Hamidreza Arabi ◽

David Haselberger ◽

Dariush Hinderberger

Keyword(s):

Drug Delivery ◽

Serum Albumin ◽

Drug Delivery Systems ◽

Delivery Systems ◽

New Materials ◽

Gel Properties ◽

Paramagnetic Resonance ◽

Physiological Conditions ◽

Human Body Temperature ◽

Electron Paramagnetic

Serum albumin has shown great potential in the development of new biomaterials for drug delivery systems. Different methods have been proposed to synthesis hydrogels out of serum albumin. It has been observed that ethanol can also act as a trigger for serum albumin denaturation and subsequent gelation. In this study, we focus on basic mechanisms of the albumin gelation process at 37 °C when using the chemical denaturant ethanol. The temperature of 37 °C was chosen to resemble human body temperature, and as under physiological conditions, albumin is in a non-denatured N conformation. As established in our previous publication for the triggers of pH and temperature (and time), we here explore the conformational and physical properties space of albumin hydrogels when they are ethanol-induced and show that the use of ethanol can be advisable for certain gel properties on the nanoscopic and macroscopic scale. To this end, we combine spectroscopic and mechanically (rheology) based data for characterizing the gels. We also study the gels′ binding capacities for fatty acids with electron paramagnetic resonance (EPR) spectroscopy, which implies observing the effects of bound stearic acids on gelation. Ethanol reduces the fraction of the strongly bound FAs in bovine serum albumin (BSA) hydrogels up to 52% and induces BSA hydrogels with a maximum storage modulus of 5000 Pa. The loosely bound FAs in ethanol-based hydrogels, besides their relatively weak mechanical properties, introduce interesting new materials for fast drug delivery systems and beyond.

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Toward New Materials Prepared via the RAFT Process: From Drug Delivery to Optoelectronics?

Handbook of RAFT Polymerization ◽

10.1002/9783527622757.ch13 ◽

2008 ◽

pp. 483-535 ◽

Cited By ~ 2

Author(s):

Arnaud Favier ◽

Bertrand de Lambert ◽

Marie-Thrse Charreyre

Keyword(s):

Drug Delivery ◽

New Materials

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A new type of defect structure in 124-superconducting oxide revealed by HREM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100089779 ◽

1991 ◽

Vol 49 ◽

pp. 1092-1093

Author(s):

R. Sharma ◽

B.L. Ramakrishna ◽

N.N. Thadhani ◽

D. Hianes ◽

Z. Iqbal

Keyword(s):

Shock Wave ◽

Defect Structure ◽

Neutron Radiation ◽

Weak Links ◽

Defect Structures ◽

New Materials ◽

New Type ◽

Current Densities ◽

Processing Techniques ◽

Microstructural Studies

After materials with superconducting temperatures higher than liquid nitrogen have been prepared, more emphasis has been on increasing the current densities (Jc) of high Tc superconductors than finding new materials with higher transition temperatures. Different processing techniques i.e thin films, shock wave processing, neutron radiation etc. have been applied in order to increase Jc. Microstructural studies of compounds thus prepared have shown either a decrease in gram boundaries that act as weak-links or increase in defect structure that act as flux-pinning centers. We have studied shock wave synthesized Tl-Ba-Cu-O and shock wave processed Y-123 superconductors with somewhat different properties compared to those prepared by solid-state reaction. Here we report the defect structures observed in the shock-processed Y-124 superconductors.

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Techniques For The Preparation of Tissue Samples Containing Injectable Polymer Microcapsules

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100120242 ◽

1985 ◽

Vol 43 ◽

pp. 710-711

Author(s):

G.E. Visscher ◽

R. L. Robison ◽

G. J. Argentieri

Keyword(s):

Drug Delivery ◽

Drug Delivery Systems ◽

Gastrocnemius Muscle ◽

Degradation Process ◽

Delivery Systems ◽

Tissue Reaction ◽

Electron Microscopic ◽

Tissue Samples ◽

Injectable Polymer ◽

Microscopic Techniques

The use of various bioerodable polymers as drug delivery systems has gained considerable interest in recent years. Among some of the shapes used as delivery systems are films, rods and microcapsules. The work presented here will deal with the techniques we have utilized for the analysis of the tissue reaction to and actual biodegradation of injectable microcapsules. This work has utilized light microscopic (LM), transmission (TEM) and scanning (SEM) electron microscopic techniques. The design of our studies has utilized methodology that would; 1. best characterize the actual degradation process without artifacts introduced by fixation procedures and 2. allow for reproducible results.In our studies, the gastrocnemius muscle of the rat was chosen as the injection site. Prior to the injection of microcapsules the skin above the sites was shaved and tattooed for later recognition and recovery. 1.0 cc syringes were loaded with the desired quantity of microcapsules and the vehicle (0.5% hydroxypropylmethycellulose) drawn up. The syringes were agitated to suspend the microcapsules in the injection vehicle.

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