How do you make a dendrimer?
Dendrimers are generally prepared using either a divergent method or a convergent one [38]. In the different methods, dendrimer grows outward from a multifunctional core molecule. The core molecule reacts with monomer molecules containing one reactive and two dormant groups, giving the first-generation dendrimer.
Which is the example of dendrimer?
Examples of several types of dendrimers include those which have immense applications in drug delivery including poly(amidoamine) (PAMAM) dendrimers, poly(propylene imine) (PPI) dendrimers, polyether-copolyester (PEPE) dendrimers, PEGylated dendrimers, peptide dendrimers, etc.
How do dendrimers work drug delivery?
Dendrimers for drug delivery are employed using two approaches: (i) formulation and (ii) nanoconstruct. In the formulation approach, drugs are physically entrapped in a dendrimer using non-covalent interactions, whereas drugs are covalently coupled on dendrimers in the nanoconstruct approach.
What is PAMAM dendrimer?
PAMAM dendrimers are a family of highly branched and mono-disperse synthetic macromolecules with well-defined structures and compositions. Synthesis of these nanocarriers can be carried out through the divergent route.
How is dendrimer different from a polymer?
Dendrimers are hyperbranched macromolecules having a perfectly defined and highly functionalized repetitive structure. In contrast to all the other types of polymers, they are not synthesized by polymerization reactions but step by step (‘layer after layer’), which allows a perfect control of their structure.
What are the types of dendrimers?
2. Types of dendrimers
| Dendrimer types | Application | Drug |
|---|---|---|
| Peptide dendrimer | Gene therapy | DNA |
| Dendronized polypeptide (denpol) dendrimer | siRNA delivery | siRNA |
| Glycodendrimers | Anti-HIV dendritic cell-based immunotherapy | – |
| Polypolypropylene oxide cored PAMAM | Solubility enhancement | Ketoprofen, diflunisal, ibuprofen |
How do dendrimers increase solubility?
As the size of drug particles decreases, the surface area increases leading to higher interaction of the drug particles with the medium; and hence improves the solubility of the compound (Blagden et al., 2007).
What does PAMAM stand for?
Poly(amidoamine), or PAMAM, is a class of dendrimer which is made of repetitively branched subunits of amide and amine functionality.
What is the meaning of PAMAM?
Polyamidoamine (PAMAM) is one of the most common dendrimers due to its biocompatibility, surface functionalizability, and ease of synthesis.
What is dendrimer polymer?
Dendrimers are highly ordered, branched polymeric molecules. Synonymous terms for dendrimer include arborols and cascade molecules. Typically, dendrimers are symmetric about the core, and often adopt a spherical three-dimensional morphology. The word dendron is also encountered frequently.
Where are dendrimers used?
Applications. Applications of dendrimers typically involve conjugating other chemical species to the dendrimer surface that can function as detecting agents (such as a dye molecule), affinity ligands, targeting components, radioligands, imaging agents, or pharmaceutically active compounds.
How do dendrimers work?
In the different methods, dendrimer grows outward from a multifunctional core molecule. The core molecule reacts with monomer molecules containing one reactive and two dormant groups, giving the first-generation dendrimer. Then, the new periphery of the molecule is activated for reactions with more monomers.
Who bought Pan Am?
Delta Air Lines
Delta Air Lines acquired Pan Am’s transatlantic routes and shuttle service prior to the carrier’s eventual collapse, fending off TWA, United Airlines, and American Airlines. The Atlanta-based operator notes that Pan Am was losing up to $3 million each day during the latter weeks of 1991.
Why did Pan Am shut down?
Attempting to quickly create a domestic system, Pan Am acquired Miami-based National Airlines in 1980. After selling most of its international routes to raise operating funds, Pan Am ended in bankruptcy in December 1991.
Why did the Pan Am fail?
Pan American World Airways, for more than five decades an unofficial symbol of the United States abroad, filed for Chapter 11 bankruptcy Tuesday, a victim of spiraling fuel prices, the deteriorating economy and the terrorist bombing of its Flight 103 over Scotland two years ago.
Why was Pan Am Cancelled?
More Stories by Jethro Nededog. It’s no secret that ABC’s Pan Am has been on the cancelation bubble due to its low ratings. Yet, the network is following through with airing its full episode order with Pan Am’s finale currently scheduled for Sunday, Feb. 19.
Why did Pan Am not survive as an airline?
“Its downfall began in the late 1970s and continued in the 1980s. The carrier failed on two fronts – it never proved successful at fending off increased competition on its international flights from powerful carriers like American, United and Delta, as well as some European airlines.
Is Pan Am based on a true story?
Earlier this year, the creators of the new ABC series PanAm reached out to dozens of real life PanAm stewardesses.
What was the downfall of Pan Am?
Why did Pan Am get Cancelled?
After failing to raise money from other sources, a phone call was made to Pan Am’s head office on December 4, 1991. The message was: “Shut it down.” Conrad: Pan American Airways went bankrupt, and they shut down services.
What caused Pan Am to fail?
Why is pan so successful?
By the mid-20th century, Pan Am enjoyed a near monopoly on international routes. It led the aircraft industry into the Jet Age by acquiring new jetliners such as the Boeing 707 and Boeing 747. Pan Am’s modern fleet allowed it to fly larger numbers of passengers, at a longer range, and with fewer stops than rivals.
When did Pan Am go bust?
In November 1991, still in trouble, it completed the sale of its transatlantic, continental European, Middle Eastern, and Asian routes to Delta Air Lines. The attempts at survival failed. In bankruptcy from January 1991, Pan American went out of business in December 1991.
Is Pan Am still operating?