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Biomedical subjects

Roey J Amir

Publications and source records attributed to Roey J Amir.

5 recordsLinked to original sources
PubMed2007

Receiver-amplifier, self-immolative dendritic device.

Self-immolative dendrimers disassemble through a domino-like chain fragmentation initiated by a single cleavage at the dendrimer core. We have designed and synthesized dendritic molecules that resemble dendritic architectures present in nature. The unique design allows a cleavage signal received by any one of the multiple triggers on one side of the dendrimer to be transferred convergently to a focal point. The signal is divergently amplified through to the other side of the dendrimer, reporter units are released, and fluorescence is emitted. During signal propagation, the dendritic molecule disassembles in a self-immolative manner into small fragments. These compounds are the longest dendritic system ever reported to disassemble through sequential self-immolative reactions. The synthesized dendritic molecules have an architecture and signal-conducting activity related to that of neurons.

Dendrimers↗
PubMed2004

Self-immolative dendrimer biodegradability by multi-enzymatic triggering.

New self-immolative dendritic molecules have been designed and synthesized. The dendrons are built with a multi-enzymatic triggering mechanism, which initiates their biodegradation through a self-immolative chain fragmentation to release a reporter group from the focal point. The dendritic backbone is constructed from polycarbamate linkages, which are stable to hydrolysis and enhance the dendrons' solubility in water. The degradation can readily take place under physiological conditions on enzymatic triggering.

Biocompatible Materials↗
PubMed2004

Chemical adaptor systems.

"Chemical adaptor systems" are molecules used to link different functionalities, based on unique reactivity that allows controlled fragmentation. Two different mechanistic reactivities were used to prepare chemical adaptor systems. The first is based on a spontaneous intra-cyclization reaction to form a stable ring molecule. Cleavage of the trigger generates a free nucleophile, for example, an amine group, which undergoes intra-cyclization to release the target molecule from the handle part (e.g., a targeting antibody or a solid support for synthesis). The second applied reactivity is an elimination reaction, which is usually based on a quinone-methide-type rearrangement. Similarly, cleavage of the trigger generates a free phenol functionality, which can undergo a self-elimination reaction through a quinone-methide rearrangement to release the target molecule. The adaptor molecules have been applied in the field of drug delivery to release a drug from a targeting device and in the field of solid-phase synthesis to release a synthetic molecule from the solid support. A chemical adaptor molecule has also been used as a building unit to construct dendrimers with a triggered fragmentation.

Antineoplastic Agents↗