845504-47-4Relevant academic research and scientific papers
Light-Sensitive Phenacyl Crosslinked Dextran Hydrogels for Controlled Delivery**
Brevé, Tobias G.,Filius, Mike,Weerdenburg, Sven,van der Griend, Stefan J.,Groeneveld, Tim P.,Denkova, Antonia G.,Eelkema, Rienk
, (2022/02/02)
Stimuli-responsive soft materials enable controlled release of loaded drug molecules and biomolecules. Controlled release of potent chemotherapeutic or immunotherapeutic agents is crucial to reduce unwanted side effects. In an effort to develop controlled release strategies that can be triggered by using Cerenkov luminescence, we have developed polymer hydrogels that can release bovine serum albumin and immunoglobulin G by using light (254 nm–375 nm) as a trigger. We describe the synthesis and photochemical characterization of two light sensitive phenacyl bis-azide crosslinkers that are used to prepare transparent self-supporting hydrogel patches. One crosslinker was designed to optimize the overlap with the Cerenkov luminescence emission window, bearing an π-extended phenacyl core, resulting in a high quantum yield (14 %) of photocleavage when irradiated with 375 nm light. We used the extended phenacyl crosslinker for the preparation of protein-loaded dextran hydrogel patches, which showed efficient and selective dosed release of bovine serum albumin or immunoglobulin G after irradiation with 375 nm light. Cerenkov-triggered release is as yet inconclusive due to unexpected side-reactivity. Based on the high quantum yield, efficient release and large overlap with the Cerenkov window, we envision application of these photosensitive soft materials in radiation targeted drug release.
PHP-Tethered N-Acyl Carbamate: A Photocage for Nicotinamide
Salahi, Farbod,Purohit, Vatsal,Ferraudi, Guillermo,Stauffacher, Cynthia,Wiest, Olaf,Helquist, Paul
, p. 2547 - 2550 (2018/05/22)
The synthesis of a new photocaged nicotinamide having an N-acyl carbamate linker and a p-hydroxyphenacyl (pHP) chromophore is described. The photophysical and photochemical studies showed an absorption maximum at λ = 330 nm and a quantum yield for release of 11% that are dependent upon both pH and solvent. While the acyl carbamate releases nicotinamide efficiently, a simpler amide linker was inert to photocleavage. This photocaged nicotinamide has significant advantages with respect to quantum yield, absorbance wavelength, rate of release, and solubility that make it the first practical example of a photocaged amide.
Ultrafast time-resolved transient absorption and resonance Raman spectroscopy study of the photodeprotection and rearrangement reactions of p-hydroxyphenacyl caged phosphates
Ma, Chensheng,Kwok, Wai Ming,Chan, Wing Sum,Du, Yong,Kan, Jovi Tze Wai,Toy, Patrick H.,Phillips, David Lee
, p. 2558 - 2570 (2007/10/03)
The kinetics and mechanism of the photodeprotection and rearrangement reactions for the pHP phototrigger compounds p-hydroxyphenacyl diethyl phosphate (HPDP) and diphenyl phosphate (HPPP) were studied using transient absorption (TA) and picosecond time-resolved resonance Raman (ps-TR3) spectroscopy. TA spectroscopy was employed to detect the dynamics of the triplet precursor decay as well as to investigate the influence of the solvent and leaving group on the triplet quenching process. Ps-TR3 spectroscopy was used to directly monitor the formation dynamics for the photosolvolytic rearrangement product and its solvent and leaving group dependence. The TA and TR3 spectroscopy experiments were also used to characterize the structural and electronic properties of the triplet precursor to the HPDP and HPPP deprotection reactions. The solvent effect observed in conjunction with the leaving group dependence of the triplet decay dynamics are consistent with a concerted solvent assisted triplet cleavage through a heterolytic mechanism for the HPDP and HPPP photodeprotection process. Correlation of the dynamics between the deprotection and rearrangement processes reveals there is a consecutive mechanism and the involvement of an intermediate between the two reaction steps. The reaction rate of the deprotection and rearrangement steps and the influence of the solvent and leaving group were determined and evaluated based on kinetic modeling of the dynamical data obtained experimentally for HPDP and HPPP in H2O/MeCN mixed solvents with varying water concentration in the solvent system. A solvation complex with a contact ion pair character was proposed to be the intermediate involved in the deprotection and rearrangement pathway. The results here combined with our previous study on the photophysical events occurring on the early picosecond time scale (Ma; et al. J. Am. Chem. Soc. 2005, 127, 1463-1472) provide a real time overall mechanistic description for the photodeprotection and rearrangement reactions of pHP caged phosphate phototrigger compounds.
Ultrafast time-resolved study of photophysical processes involved in the photodeprotection of p-hydroxyphenacyl caged phototrigger compounds
Ma, Chensheng,Wai, Ming Kwok,Wing, Sum Chan,Zuo, Peng,Kan, Jovi Tze Wai,Toy, Patrick H.,Phillips, David Lee
, p. 1463 - 1472 (2007/10/03)
A combined femtosecond Kerr gated time-resolved fluorescence (fs-KTRF) and picosecond Kerr gated time-resolved resonance Raman (ps-KTR3) study is reported for two p-hydroxyphenacyl (pHP) caged phototriggers, HPDP and HPA, in neat acetonitrile a
