Received Jan 20; Accepted Mar This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract The complex dibutyltin 2-oxophenylacetic acid 4-hydroxybenzohydrazone has been synthesized and characterized by elemental analysis, IR, 1H and 13C NMR, and X-ray single-crystal diffraction studies.
Editor who approved publication: For successful design of a nanoparticulate drug delivery system, the fate of the carrier and cargo need to be followed.
The nanocapsules were formed by interfacial anionic polymerization on aqueous droplets generated by an inverse miniemulsion process. After uptake, the PBCA capsules were shown to be round-shaped, endosomal structures and the payload was successfully released.
Cy5-labeled oligonucleotides accumulated at the mitochondrial membrane due to a combination of the high mitochondrial membrane potential and the specific molecular structure of Cy5. The specificity of this accumulation at the mitochondria was shown as the uncoupler dinitrophenol rapidly diminished the accumulation of the Cy5-labeled oligonucleotide.
As oligonucleotides are an ideal model system for small interfering RNA PBCA nanocapsules demonstrate to be a versatile delivery platform for small interfering RNA to treat a variety of diseases.
Nanotechnology-based drug and gene delivery systems made of polymeric materials like nanoparticles or nanocapsules, 2 liposomes, 3 and polyplexes 45 have the potential to solve these problems. Biocompatibility and biodegradation play a key role in drug carrier systems.
These requirements are fulfilled both in the application of polymers like poly alkylcyanoacrylatesknown as skin adhesives or surgical glues for the closure of wounds. In addition to being approved in medical applications, poly n-butylcyanoacrylate PBCA nanoparticles have been demonstrated to cross the blood—brain barrier efficiently.
In contrast, the present work focused on PBCA nanocapsules as a nanocarrier system that overcomes cellular and intracellular barriers on a microscopic level and releases its payload inside the cell.
Confocal imaging was used to demonstrate release of oligonucleotides from the nanocapsules into the cytoplasm. At the single-cell level, fluorescence microscopy enables detection of subcellular structures in living cells, like the cytoskeleton, mitochondria, and organelles of the endocytotic pathway in high resolution after staining these cell compartments with appropriate fluorescent markers.
Here and in previous work we have used Cy5-labeled oligonucleotides as a model cargo for siRNA in view of their several advantages. Oligonucleotides are inexpensive because they are widely synthesized as primers for polymerase chain reaction. Modifications to the nucleotide sequence as well as different fluorescent labels on both ends of the sequence are readily available.
For a drug delivery device, it is crucial to understand its efficiency in terms of protecting its cargo from degradation and delivering it to the intracellular site of interest. For toxicological considerations, it is important to determine what happens to the polymeric capsule material.
While recent studies 11 demonstrated that PBCA with Cy5-labeled oligonucleotides was readily taken up into endosomes and the fluorescence of the cyanine dye escaped the endosomes and located to the mitochondria, they did not investigate whether the oligonucleotide was still attached to the Cy5 dye as a whole or if the nucleotide sequence was cleaved.
The present work also focused on determination of the intracellular fate of the polymeric shell, ie, the PBCA itself. The polymer itself was labeled covalently by 5-carboxytetramethylrhodamine azide TAMRAa rhodamine dye. The advantage of labeling both the content and the shell of the capsule enabled specific detection of both the payload and the capsule material and the fate of both after cellular uptake.
All chemicals were used without further purification. Demineralized water was used throughout the experiments. Preparation of nanocapsules Preparation of the inverse miniemulsion and polymerization took place at the droplet interfaces according to a previously published procedure.
The continuous phase and oil phase 3. An aqueous buffer made of Tris HCl, MgCl2, KCl, gelatin, and water formed the basis of the aqueous phase see previous paragraph for amounts. The aqueous phase and continuous phase were mixed and then stirred for one hour to form an emulsion.
The wet pellet was redispersed in a 0.
The dispersion was degassed by argon bubbling for 15 minutes. Next, the nanocapsules were centrifuged Sigma-Aldrich, 3k, RCF20 minutesand the wet pellet was redispersed in a 0.
For morphological observation, transmission electron microscopy was carried out using an EM electron microscope Philips, Eindhoven, the Netherlands operating with an acceleration voltage of 80 kV. The samples were prepared by diluting the capsule dispersion with demineralized water to a solid content of about 0.
One droplet of the sample was placed on a carbon-coated copper mesh and left to dry overnight at ambient temperature. No additional contrasting was applied.
The total solid content was measured gravimetrically.“Analysis of the Murine Immune Response to Pulmonary Delivery of Precisely Fabricated Nano- and Microscale Particles“; Roberts, R.
A.; Shen “Oxidative Dissolution of Copper and Zinc Metal in Carbon Dioxide with tert-Butyl Peracetate and a -Diketone Chelating Agent”; Visintin “Synthesis and Characterization of Poly(1-butene.
Synthesis of styrene Anionic polymerization of butadiene using n-butyl or sec-butyl lithium as initiator leads typically to microstructures with a composition of 35% 1,4 cis, 55% 1,4 trans, and 10% recipe as in microscale experiments, were prepared in an APV Gaulin (LAB) using a loop arrangement.
Evaluation of N 2-butyl cyanoacrylate adhesive material in the fixation of dentoalveolar mandibular fractures in dogs. Synthesis and characterization of novel elastomeric poly(D,L-lactide urethane) maleate composites for bone tissue engineering Applications of Microscale Technologies for Regenerative Dentistry.
3 June | Journal of. This text is an unbound, binder-ready edition. This is a laboratory text for the mainstream organic chemistry course taught at both two and four year schools, featuring both microscale experiments and options for scaling up appropriate experiments for use in the macroscale lab.
Microscale Organic Laboratory With Multistep & Multiscale Syntheses by Dana W Mayo available in Ring Binder on alphabetnyc.com, also read synopsis and reviews.
This text is an unbound, binder-ready alphabetnyc.com is a laboratory text for the mainstream organic. Microscale Synthesis and Characterization of Butyl 2-Cyano(2-Ethyl-Phenyl)Propenoate Project #4 Maura Estes 17 October Introduction: Before conducting the scale-up synthesis of the TSE compound, a microscale synthesis and characterization was carried out to confirm the structure and to verify that the targeted TSE product is being synthesized.