Hasil untuk "Chemistry"

R. Bergman

C. Felser, G. Fecher, B. Balke

V. Sridharan, Padmakar A. Suryavanshi, J. Menéndez

F. S. Chakar, A. Ragauskas

H. Sverdrup, Martin W. Johnson, R. H. Fleming

B. Finlayson‐Pitts, J. Pitts

E. Lewars

M. Mcqueen, L. Mon

Clinical

Chao‐Jun Li, Liang Chen

H. D. Holland

K. Jähnisch, V. Hessel, H. Löwe et al.

R. M. Barrer

P. Walstra, R. Jenness

R. Handy, F. Kammer, J. Lead et al.

S. Suman, P. Joseph

Paresh Agarwal, C. Bertozzi

Antibody–drug conjugates (ADCs) combine the specificity of antibodies with the potency of small molecules to create targeted drugs. Despite the simplicity of this concept, generation of clinically successful ADCs has been very difficult. Over the past several decades, scientists have learned a great deal about the constraints on antibodies, linkers, and drugs as they relate to successful construction of ADCs. Once these components are in hand, most ADCs are prepared by nonspecific modification of antibody lysine or cysteine residues with drug-linker reagents, which results in heterogeneous product mixtures that cannot be further purified. With advances in the fields of bioorthogonal chemistry and protein engineering, there is growing interest in producing ADCs by site-specific conjugation to the antibody, yielding more homogeneous products that have demonstrated benefits over their heterogeneous counterparts in vivo. Here, we chronicle the development of a multitude of site-specific conjugation strategies for assembly of ADCs and provide a comprehensive account of key advances and their roots in the fields of bioorthogonal chemistry and protein engineering.

Manjinder Singh, Maninder Kaur, O. Silakari

Hui Yang, Bin Yuan, Xi Zhang et al.

Tyson J Smyth, K. Petrova, N. M. Payton et al.

A method for conjugation of ligands to the surface of exosomes was developed using click chemistry. Copper-catalyzed azide alkyne cycloaddition (click chemistry) is ideal for biocojugation of small molecules and macromolecules to the surface of exosomes, due to fast reaction times, high specificity, and compatibility in aqueous buffers. Exosomes cross-linked with alkyne groups using carbodiimide chemistry were conjugated to a model azide, azide-fluor 545. Conjugation had no effect on the size of exosomes, nor was there any change in the extent of exosome adherence/internalization with recipient cells, suggesting the reaction conditions were mild on exosome structure and function. We further investigated the extent of exosomal protein modification with alkyne groups. Using liposomes with surface alkyne groups of a similar size and concentration to exosomes, we estimated that approximately 1.5 alkyne groups were present for every 150 kDa of exosomal protein.

Zahra Tavakoli, Khosro Khajeh, Bijan Ranjbar

Prostate cancer is the second most common cancer globally, causing ≈396,792 deaths in 2022. Early diagnosis and advanced drug delivery are vital to prevent its progression. This research leverages the anticancer properties of selenium nanoparticles and enzalutamide, a leading prostate cancer drug, by coencapsulating them within mesoporous silica nanoparticles (MSNPs). MSNPs offer advantages for drug delivery, including high surface accessibility and a tunable porous structure. The results indicated that MSNPs synthesized via solvent extraction, yielding a specific surface area of 1017.4 m2/g, a pore volume of 0.2531 cm3/g, and an average pore size of ≈10 nm, were superior to those obtained by calcination, which yielded a smaller pore size (≈3 nm). Enzalutamide was loaded into these selenium‐embedded MSNPs, achieving a drug loading efficiency of 76.3 ± 0.5%. Separately, curcumin was encapsulated in chitosan nanoparticles with high efficiency (83.2 ± 0.7%). The combined nanosystem enables pH‐responsive, gradual drug release that mimics the tumor microenvironment. MTT assays confirmed the drug‐loaded system exerts significantly stronger, time‐ and concentration‐dependent anticancer effects than the free drug. Furthermore, curcumin plays a vital role in enhancing anticancer efficacy and inducing apoptosis. This research demonstrates that the designed dual‐nanoparticle system is a promising candidate for targeted prostate cancer therapy.