Parkinson's & Movement disorders

Drug homing method helps rethink Parkinson's

The brain is the body's most complex organ, and consequently the least understood. In fact, researchers like Michael Tadross, MD, PhD, wonder if the current research methods employed by neuroscientists are telling us as much ...

Oncology & Cancer

Extracellular vesicles could be personalized drug delivery vehicles

Creating enough nanovesicles to inexpensively serve as a drug delivery system may be as simple as putting the cells through a sieve, according to an international team of researchers who used mouse autologous—their own—immune ...

Oncology & Cancer

Double targeting ligands to identify and treat prostate cancer

Researchers have demonstrated a new, effective way to precisely identify and localize prostate cancer tumors while protecting healthy tissue and reducing side effects. The new approach utilizes a single molecule designed ...

Medications

Cyclic opioid peptides

Peptide based drug candidates are being discovered at an increasingly rapid pace as therapeutics for many diseases and pain management. . For decades the opioid receptors have been an attractive therapeutic target for pain ...

Cell & Microbiology

T cells use 'handshakes' to sort friends from foes

T cells, the security guards of the immune system, use a kind of mechanical "handshake" to test whether a cell they encounter is a friend or foe, a new study finds.

Immunology

Study suggests remarkable approach to MS treatment

(Medical Xpress)—Multiple sclerosis (MS) is an autoimmune inflammatory disorder in which the immune system attacks the myelin sheath enveloping and insulating the nerves. A progressive disease that often results in severe ...

Medical research

Researchers study novel drug-delivery system

University of Mississippi School of Pharmacy researchers are studying an improved method for delivering drugs that treat pain and inflammation.

Genetics

A single DNA tweak leads to blond hair

A single-letter change in the genetic code is enough to generate blond hair in humans, in dramatic contrast to our dark-haired ancestors. A new analysis by Howard Hughes Medical Institute (HHMI) scientists has pinpointed ...

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Ligand

In coordination chemistry, a ligand is an ion or molecule (see also: functional group) that binds to a central metal atom to form a coordination complex. The bonding between metal and ligand generally involves formal donation of one or more of the ligand's electron pairs. The nature of metal-ligand bonding can range from covalent to ionic. Furthermore, the metal-ligand bond order can range from one to three. Ligands are viewed as Lewis bases, although rare cases are known involving Lewis acidic "ligands."

Metal and metalloids are bound to ligands in virtually all circumstances, although gaseous "naked" metal ions can be generated in high vacuum. Ligands in a complex dictate the reactivity of the central atom, including ligand substitution rates, the reactivity of the ligands themselves, and redox. Ligand selection is a critical consideration in many practical areas, including bioinorganic and medicinal chemistry, homogeneous catalysis, and environmental chemistry.

Ligands are classified in many ways: their charge, their size (bulk), the identity of the coordinating atom(s), and the number of electrons donated to the metal (denticity or hapticity). The size of a ligand is indicated by its cone angle.

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