A spiropyran–coumarin platform: an environment sensitive photoresponsive drug delivery system for efficient cancer therapy

Abstract

In spite of inventing several anticancer agents the clinical payoff still remains unsatisfactory because of their severe host toxicity due to their nonspecific biodistribution in the body.

Ratiometric Cu2+ Binding, Cell Imaging, Mitochondrial Targeting, and Anticancer Activity with Nanomolar IC50 by Spiro-Indoline-Conjugated Calix[4]arene

“…The L exhibits three major absorption bands centered at 202, 292, and 379 nm in acetonitrile and a major emission band at 475 nm with a strong shoulder at 570 nm when excited at 379 nm (excitation spectrum of L given in Figure S09). The spiro-indoline system is known to undergo ring opening, 16 which is further expected to be stabilized by a transition-metal ion. Addition of trifluoroacetic acid (TFA) to L leads to the transformation of the closed ring form to that of the ring-open form, which was evident from the observed increase in the absorbance at 420 nm.…”

Stimuli‐Responsive Biomaterials for Vaccines and Immunotherapeutic Applications

“…For this, they caged drugs in acid‐activated spiropyran and photo‐responsive shells composed of coumarin moieties enabling site‐specific and dose‐dependent release of drugs at the tumor site through an external light source. [ 78 ]…”

“…One example of a multi‐stimuli‐responsive therapy is pH‐ and light‐responsive micelles that allow for triggered release of therapeutics at tumor sites as an effective cancer therapy. [ 78,79 ] The spatiotemporal fine‐tuning of stimuli prevents off‐target cytotoxicity associated with many drugs, including chemotherapy agents and enhances drug‐release for a more potent response. Another example of multi‐stimuli‐responsive materials is where dual‐responsive pH and redox saccharide‐based NPs were designed to induce maximal drug release specifically at the tumor site, a low pH and reductive GSH microenvironment.…”

RATIOMETRIC NEAR-INFRARED FLUORESCENT PROBES FOR THE SENSITIVE DETECTION OF INTRACELLULAR pH AND BIO-THIOLS IN LIVE CELLS

“…96,[186][187][188]190 Spiropyran molecular switches have been widely utilized in the design of optical probes because they respond reversibly to chemical stimuli through chemical structural changes. [191][192][193][194] Most optical probes are based on absorbance changes involving conversion between the spiropyran and hemicyanine forms due to an external stimulus, and many often lack ratiometric fluorescence responses because of non-fluorescent spiropyran forms. [191][192][193][194][195][196] pH.…”

“…[191][192][193][194] Most optical probes are based on absorbance changes involving conversion between the spiropyran and hemicyanine forms due to an external stimulus, and many often lack ratiometric fluorescence responses because of non-fluorescent spiropyran forms. [191][192][193][194][195][196] pH. 88,91,93,95,198,199 The cells were then incubated with 10 µM probe A or probe B for 15 min and then rinsed with FBS buffer twice before imaging.…”