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Chemistry (Weinheim An Der Bergstrasse,... Mar 2021Photochemistry provides a wide range of alternative reagents that hold potential for use in bimolecular functionalisation of proteins. Here, we report the synthesis and...
Photochemistry provides a wide range of alternative reagents that hold potential for use in bimolecular functionalisation of proteins. Here, we report the synthesis and characterisation of metal ion binding chelates derivatised with disubstituted tetrazoles for the photoradiochemical labelling of monoclonal antibodies (mAbs). The photophysical properties of tetrazoles featuring extended aromatic systems and auxochromic substituents to tune excitation toward longer wavelengths (365 and 395 nm) were studied. Two photoactivatable chelates based on desferrioxamine B (DFO) and the aza-macrocycle NODAGA were functionalised with a tetrazole and developed for protein labelling with Zr, Cu and Ga radionuclides. DFO-tetrazole (1) was assessed by direct conjugation to formulated trastuzumab and subsequent radiolabelling with Zr. Radiochemical studies and cellular-based binding assays demonstrated that the radiotracer remained stable in vitro retained high immunoreactivity. Positron emission tomography (PET) imaging and biodistribution studies were used to measure the tumour specific uptake and pharmacokinetic profile in mice bearing SK-OV-3 xenografts. Experiments demonstrate that tetrazole-based photochemistry is a viable approach for the light-induced synthesis of PET radiotracers.
Topics: Animals; Cell Line, Tumor; Mice; Molecular Imaging; Photochemistry; Positron-Emission Tomography; Tetrazoles; Tissue Distribution; Zirconium
PubMed: 33427351
DOI: 10.1002/chem.202100061 -
Molecules (Basel, Switzerland) Feb 2023One of the challenges in developing practical CO photoconversion catalysts is the design of materials with a low cost, high activity and good stability. In this paper,... (Review)
Review
One of the challenges in developing practical CO photoconversion catalysts is the design of materials with a low cost, high activity and good stability. In this paper, excellent photocatalysts based on TiO, WO, ZnO, CuO and CeO metal oxide materials, which are cost-effective, long-lasting, and easy to fabricate, are evaluated. The characteristics of the nanohybrid catalysts depend greatly on their architecture and design. Thus, we focus on outstanding materials that offer effective and practical solutions. Strategies to improve CO conversion efficiency are summarized, including heterojunction, ion doping, defects, sensitization and morphology control, which can inspire the future improvement in photochemistry. The capacity of CO adsorption is also pivotal, which varies with the morphological and electronic structures. Forms of 0D, 1D, 2D and 3DOM (zero/one/two-dimensional- and three-dimensional-ordered macroporous, respectively) are involved. Particularly, the several advantages of the 3DOM material make it an excellent candidate material for CO conversion. Hence, we explain its preparation method. Based on the discussion, new insights and prospects for designing high-efficient metallic oxide photocatalysts to reduce CO emissions are presented.
Topics: Carbon Dioxide; Adsorption; Electronics; Oxides; Photochemistry
PubMed: 36838641
DOI: 10.3390/molecules28041653 -
Chemical Reviews Jan 2022Photoinduced chemical transformations have received in recent years a tremendous amount of attention, providing a plethora of opportunities to synthetic organic... (Review)
Review
Photoinduced chemical transformations have received in recent years a tremendous amount of attention, providing a plethora of opportunities to synthetic organic chemists. However, performing a photochemical transformation can be quite a challenge because of various issues related to the delivery of photons. These challenges have barred the widespread adoption of photochemical steps in the chemical industry. However, in the past decade, several technological innovations have led to more reproducible, selective, and scalable photoinduced reactions. Herein, we provide a comprehensive overview of these exciting technological advances, including flow chemistry, high-throughput experimentation, reactor design and scale-up, and the combination of photo- and electro-chemistry.
Topics: Inventions; Photochemistry
PubMed: 34375082
DOI: 10.1021/acs.chemrev.1c00332 -
Journal of Materials Science. Materials... Aug 2020The nervous system is a crucial component of the body and damages to this system, either by injury or disease, can result in serious or potentially lethal consequences....
The nervous system is a crucial component of the body and damages to this system, either by injury or disease, can result in serious or potentially lethal consequences. An important problem in neural engineering is how we can stimulate the regeneration of damaged nervous tissue given its complex physiology and limited regenerative capacity. To regenerate damaged nervous tissue, this study electrospun three-dimensional nanoscaffolds (3DNSs) from a biomaterial blend of silk fibroin (SF), polyethylene glycol (PEG), and polyvinyl alcohol (PVA). The 3DNSs were characterised to ascertain their potential suitability for direct implant into the CNS. The biological activity of 3DNSs was investigated in vitro using PC12 cells and their effects on reactive astrogliosis were assessed in vivo using a photothrombotic model of ischaemic stroke in mice. Results showed that the concentration of SF directly affected the mechanical characteristics and internal structure of the 3DNSs, with formulations presenting as either a gel-like structure (SF ≥ 50%) or a nanofibrous structure (SF ≤ 40%). In vitro assessment revealed increased cell viability in the presence of the 3DNSs and in vivo assessment resulted in a significant decrease in glial fibrillary acidic protein (GFAP) expression in the peri-infarct region (p < 0.001 for F2 and p < 0.05 for F4) after stroke, suggesting that 3DNSs could be suppressing reactive astrogliosis. The findings enhanced our understanding of physiochemical interactions between SF, PEG, and PVA, and elucidated the potential of 3DNSs as a potential therapeutic approach to stroke recovery, especially if these are used in conjunction with drug or cell treatment.
Topics: Animals; Biocompatible Materials; Biophysics; Cell Proliferation; Cell Survival; Electrochemistry; Fibroins; Glial Fibrillary Acidic Protein; Gliosis; Immunohistochemistry; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Microscopy, Electron, Scanning; Nanofibers; Nanoparticles; Neurons; PC12 Cells; Photochemistry; Polyethylene Glycols; Polyvinyl Alcohol; Rats; Regeneration; Rheology; Silk; Stroke; Thrombosis; Tissue Engineering; Tissue Scaffolds
PubMed: 32857207
DOI: 10.1007/s10856-020-06422-5 -
Nature Communications Jun 2022Photoremovable protecting groups (PPGs) represent one of the main contemporary implementations of photochemistry in diverse fields of research and practical...
Photoremovable protecting groups (PPGs) represent one of the main contemporary implementations of photochemistry in diverse fields of research and practical applications. For the past half century, organic and metal-complex PPGs were considered mutually exclusive classes, each of which provided unique sets of physical and chemical properties thanks to their distinctive structures. Here, we introduce the meso-methylporphyrin group as a prototype hybrid-class PPG that unites traditionally exclusive elements of organic and metal-complex PPGs within a single structure. We show that the porphyrin scaffold allows extensive modularity by functional separation of the metal-binding chromophore and up to four sites of leaving group release. The insertion of metal ions can be used to tune their spectroscopic, photochemical, and biological properties. We provide a detailed description of the photoreaction mechanism studied by steady-state and transient absorption spectroscopies and quantum-chemical calculations. Our approach applied herein could facilitate access to a hitherto untapped chemical space of potential PPG scaffolds.
Topics: Ions; Light; Metals; Photochemistry; Porphyrins
PubMed: 35750661
DOI: 10.1038/s41467-022-31288-2 -
Molecules (Basel, Switzerland) May 2021In order to improve their bioapplications, inorganic nanoparticles (NPs) are usually functionalized with specific biomolecules. Peptides with short amino acid sequences... (Review)
Review
In order to improve their bioapplications, inorganic nanoparticles (NPs) are usually functionalized with specific biomolecules. Peptides with short amino acid sequences have attracted great attention in the NP functionalization since they are easy to be synthesized on a large scale by the automatic synthesizer and can integrate various functionalities including specific biorecognition and therapeutic function into one sequence. Conjugation of peptides with NPs can generate novel theranostic/drug delivery nanosystems with active tumor targeting ability and efficient nanosensing platforms for sensitive detection of various analytes, such as heavy metallic ions and biomarkers. Massive studies demonstrate that applications of the peptide-NP bioconjugates can help to achieve the precise diagnosis and therapy of diseases. In particular, the peptide-NP bioconjugates show tremendous potential for development of effective anti-tumor nanomedicines. This review provides an overview of the effects of properties of peptide functionalized NPs on precise diagnostics and therapy of cancers through summarizing the recent publications on the applications of peptide-NP bioconjugates for biomarkers (antigens and enzymes) and carcinogens (e.g., heavy metallic ions) detection, drug delivery, and imaging-guided therapy. The current challenges and future prospects of the subject are also discussed.
Topics: Angiogenesis Inhibitors; Animals; Antineoplastic Agents; Biomarkers; Biosensing Techniques; Cell Line, Tumor; Chemistry, Inorganic; Colorimetry; Drug Carriers; Drug Delivery Systems; Humans; Ions; Ligands; Matrix Metalloproteinase 7; Metals, Heavy; Nanomedicine; Nanoparticles; Neoplasms; Peptides; Photochemistry; Precision Medicine; Spectrophotometry, Ultraviolet; Tumor Microenvironment
PubMed: 34072160
DOI: 10.3390/molecules26113228 -
Photochemistry and Photobiology Mar 2022Mutual transformations of various nitrogen compounds and their reaction mechanisms have been a subject of great concern to the chemical, ecological and environmental...
Mutual transformations of various nitrogen compounds and their reaction mechanisms have been a subject of great concern to the chemical, ecological and environmental communities. In the paper, the reactions of ion with small organic acids such as formic acid (HCOOH), acetic acid (CH COOH) and lactic acid (C H O ) under ultraviolet illumination were investigated systematically. It was found that ion is easily reduced into and NO and then further into N and NH (in the form of ) in the process. The carboxyl anion radicals and hydrogen formed by photodecomposition of formic acid are responsible for the rapid photoreduction reaction of nitrate. The initial pH and the nitrate concentration considerably affect the product distribution and nitrate conversion. Based on a preliminary simulation study, we speculated that the photoinduced reaction may effectively proceed in oceans, lakes and rivers because of ever-increasing nitrate and organic emissions. This research is helpful to understand nitrogen cycle mechanism and develop water environmental control technologies.
Topics: Formates; Nitrates; Photochemistry; Ultraviolet Rays
PubMed: 34515997
DOI: 10.1111/php.13518 -
Journal of Natural Products Jul 2021The tropolone-bearing sesquiterpenes juniperone A () and norjuniperone A () were isolated from the folk medicinal plant , and their structures were determined by a...
The tropolone-bearing sesquiterpenes juniperone A () and norjuniperone A () were isolated from the folk medicinal plant , and their structures were determined by a combination of spectroscopic and crystallographic methods. Photojuniperones A1 () and A2 (), bearing bicyclo[3,2,0]heptadienones derived from tropolone, were photochemically produced and structurally identified by spectroscopic methods. Predicted by the machine learning-based assay, significantly inhibited the action of tyrosinase. The new compounds also inhibited lipid accumulation and enhanced the extracellular glycerol excretion.
Topics: Animals; Hep G2 Cells; Humans; Juniperus; Melanocytes; Mice; Molecular Structure; Monophenol Monooxygenase; Photochemistry; Phytochemicals; Plants, Medicinal; Republic of Korea; Sesquiterpenes; Tropolone; Wood
PubMed: 34236881
DOI: 10.1021/acs.jnatprod.1c00321 -
Photochemical & Photobiological... May 2022Chemical actinometers are a useful tool in photochemistry, which allows to measure the photon flux of a light source to carry out quantitative analysis on...
Chemical actinometers are a useful tool in photochemistry, which allows to measure the photon flux of a light source to carry out quantitative analysis on photoreactions. The most commonly employed actinometers so far show minor drawbacks, such as difficult data treatment, parasite reactions, low stability or impossible reset. We propose herewith the use of 4,4'-dimethylazobenzene as a chemical actinometer. This compound undergoes a clean and efficient E/Z isomerization, approaching total conversion upon irradiation at 365 nm. Thanks to its properties, it can be used to determine the photon flux in the UV-visible region, with simple experimental methods and data treatment, and with the possibility to be reused after photochemical or thermal reset.
Topics: Photochemistry; Photons
PubMed: 35034332
DOI: 10.1007/s43630-021-00162-3 -
Carbohydrate Polymers Mar 2021Hydrogels are widely used in the biomedical field, due to their high similarity to native extracellular matrix (ECM). Most responsive hydrogels could only passively...
Hydrogels are widely used in the biomedical field, due to their high similarity to native extracellular matrix (ECM). Most responsive hydrogels could only passively receive stimuli and independently change their properties. In this study, a photosensitive o-nitrobenzyl (NB) ester linker of polyethylene glycol (PEG) with maleimido (Mal) as terminal groups (PEG-NB-Mal) and a 5-methylfurfuryl (mF) grafted carboxymethyl chitosan (CMCS) derivative (CMCS-mF) were synthesized and used to prepare functional hydrogels via Diels-Alder (DA) reactions. The hydrogel exhibited programmable degradation properties after sequential exposure to UV light and acid treatments. It can maintain high integrity upon the single stimuli, the cascade acid and UV light treatments or the cascade UV light and alkaline treatments. Moreover, the hydrogel exhibited well controlled release profile of rhodamine B (RB). In summary, such CMCS-based hydrogels show great potential in biomedical applications. In addition, the usage of photo-induced cascade reaction in sequential degradation hydrogels can be extended to design other types of programmable smart materials.
Topics: Acids; Chitosan; Cycloaddition Reaction; Drug Liberation; Hydrogels; Magnetic Resonance Spectroscopy; Photochemistry; Polyethylene Glycols; Polysaccharides; Rhodamines; Spectrophotometry, Ultraviolet; Spectroscopy, Fourier Transform Infrared; Ultraviolet Rays
PubMed: 33483085
DOI: 10.1016/j.carbpol.2020.117609