Read by QxMD icon Read

Bioconjugate Chemistry

Vijay Chudasama, Francesca Bryden, Huguette Savoie, Antoine Maruani, Miffy Cheng, Andrew Beeby, Joao Rodrigues, Ross W Boyle
Exploitation of photosensitisers as payloads for antibody-based anti-cancer therapeutics offers a novel alternative to the small pool of commonly-utilised cytotoxins. However, existing bioconjugation methodologies are incompatible with the requirement of increased antibody loading without compromising antibody function, stability or homogeneity. Herein, we describe the first application of dendritic multiplier groups to allow the loading of more than 4 porphyrins to a full IgG antibody in a site-specific and highly homogeneous manner...
December 7, 2017: Bioconjugate Chemistry
Sudha Shankar, Mir Mohd Faheem, Debasis Nayak, Naiem Ahmad Wani, Saleem Farooq, Surrinder Koul, Anindya Goswami, Rajkishor Rai
The present work describes the synthesis, characterization and anticancer properties of c(Lys-Pro), P1; c(Orn-Pro), P2 and conjugates PA-c(Lys-Pro), C1; PA-c(Orn-Pro), C2; EPA-c(Lys-Pro), C3 and EPA-c(Orn-Pro), C4. Among all, conjugate C4 displays potent anti-cancer activity with IC50 1.3μM in MDA-MB-231, 3.5 µM in PC-3, 8.9μM in MCF-7 and 9.6 μM in Miapaca-2 cancer cells. In addition, C4 down regulates the expression of MDM2 and abrogates the cancer cell invasion/metastasis. Through knock-down MDM2, we demonstrate that this abrogation of metastasis by C4 is primarily MDM2 dependent...
December 7, 2017: Bioconjugate Chemistry
Luping Zheng, Yunfei Wang, Xianshuo Zhang, Liwei Ma, Baoyan Wang, Xiangling Ji, Hua Wei
Dendrimer with hyperbranched structure and multivalent surface is regarded as one of the most promising candidates close to the ideal drug delivery systems, but the clinical translation and scale-up production of dendrimer has been hampered significantly by the synthetic difficulties. Therefore there is considerable scope for the development of novel hyperbranched polymer that can not only address the drawbacks of dendrimer but maintain its advantages. The reversible addition-fragmentation chain transfer self-condensing vinyl polymerization (RAFT-SCVP) technique has enabled facile preparation of segmented hyperbranched polymer (SHP) by using chain transfer monomer (CTM)-based double-head agent during the past decade...
December 7, 2017: Bioconjugate Chemistry
Iontcho R Vlahov, Longwu Qi, Paul J Kleindl, Hari K Santhapuram, Albert Felten, Garth L Parham, Kevin Wang, Fei You, Jeremy F Vaughn, Spencer J Hahn, Hanna F Klein, Marilynn Vetzel, Joseph A Reddy, Melissa Nelson, Jeff Nicoson, Christopher P Leamon
Pyrrolobenzodiazepines (PBDs) and their dimers (bis-PBDs) have emerged as some of the most potent chemotherapeutic compounds, and are currently under development as novel payloads in antibody-drug conjugates (ADCs). However, when used as stand-alone therapeutics or as warheads for small molecule drug conjugates (SMDCs), dose-limiting toxicities are often observed. As an elegant solution to this inherent problem, we designed diazepine-ring-opened conjugated prodrugs lacking the imine moiety. Once the prodrug (pro-PBD) conjugate enters a targeted cell, cleavage of the linker system triggers the generation of a reactive intermediate possessing an aldehyde and aromatic amine...
December 6, 2017: Bioconjugate Chemistry
Terese Soudah, Maxim Mogilevsky, Rotem Karni, Eylon Yavin
Efficient delivery of oligonucleotides still remains a challenge in the field of oligonucleotide based therapy. Peptide nucleic acid (PNA), a DNA analogue that is typically synthesized by solid phase peptide chemistry, has been conjugated to a variety of cell penetrating peptides (CPP) as a means of improving its cellular uptake. These CPPs typically deliver their cargoes into cells by an endosomal-dependent mechanism resulting in lower bioavailability of the cargo. Herein, we designed and synthesized PNA-peptide conjugates as splice switching oligonucleotides (SSO) targeting the Mnk2 gene, a therapeutic target in cancer...
December 6, 2017: Bioconjugate Chemistry
Troels Elmer Jeppesen, Lotte Kellemann Kristensen, Carsten Haagen Nielsen, Lars Christian Petersen, Jesper Bøggild Kristensen, Carsten Behrens, Jacob Madsen, Andreas Kjær
A method for site-specific radiolabelling of the serine protease active site inhibited factor seven (FVIIai) with 64Cu has been applied using a biorthogonal click reaction. FVIIai binds to tissue factor (TF), a trans-membrane protein involved involved in haemostasis, angiogenesis, proliferation, cell migration, and survival of cancer cells. First a single azide moiety was introduced in the active site of this 50 kDa protease. Then a NOTA moiety was introduced via a strain promoted azide-alkyne reaction and the corresponding conjugate was labelled with 64Cu...
December 5, 2017: Bioconjugate Chemistry
Sheldon Berke, Anne-Larissa Kampmann, Melinda Wuest, Justin J Bailey, Britta Glowacki, Frank Wuest, Klaus Jurkschat, Ralf Weberskirch, Ralf Schirrmacher
Nanoparticles represent the most widely studied drug delivery systems targeting cancer. Polymeric nanoparticles can be easily generated through a microemulsion polymerization. Herein, the synthesis, radiolabeling, and in vivo evaluation of nanoparticles (NPs) functionalized by an organosilicon fluoride acceptor (SiFA) are reported which can be radiolabeled without further chemical modifications. Four nanoparticles in the sub-100 nm range with distinct hydrodynamic diameters of 20 nm (NP1), 33 nm (NP2), 45 nm (NP3), and 72 nm (NP4), respectively, were synthesized under size-controlled conditions...
December 4, 2017: Bioconjugate Chemistry
Colin Fred Greineder, Carlos H Villa, Landis R Walsh, Raisa Y Kiseleva, Elizabeth D Hood, Makan Khoshnejad, Robert Warden-Rothman, Andrew Tsourkas, Vladimir R Muzykantov
Conjugation of antibodies to drugs and drug carriers improves delivery to target tissues. Widespread implementation and effective translation of this pharmacologic strategy awaits development of affinity ligands capable of a defined degree of modification and highly efficient bioconjugation without loss of affinity. To date, such ligands are lacking for the targeting of therapeutics to vascular endothelial cells. To enable site-specific click chemistry conjugation to therapeutic cargo, we used the bacterial transpeptidase, sortase A, to attach short azidolysine containing peptides to three endothelial-specific single chain antibody fragments (scFv)...
December 4, 2017: Bioconjugate Chemistry
Keiko Esashika, Toshiharu Saiki
The efficiency of gold nanoparticle (AuNP) dimerization mediated by hybridization between two probe DNA molecules and a complementary target DNA molecule was maximized by examining several possible hybridization combinations. The uniformity of the size of the AuNPs, the use of surface modification appropriate for high hybridization efficiency, together with efficient blocking of nonspecific binding, all contributed to achieving a 1-pM detection limit following conventional gel electrophoresis separation of the DNA-modified AuNP multimers...
December 4, 2017: Bioconjugate Chemistry
Zhe Tan, Yogesh K Dhande, Theresa M Reineke
A series of 3-guanidinopropyl methacrylamide (GPMA)-based polymeric gene delivery vehicles were developed via aqueous reversible addition-fragmentation chain transfer (RAFT) polymerization. The polymers have been evaluated for their cellular internalization ability, transfection efficiency, and cytotoxicity. Two homopolymers: P(GPMA20), P(GPMA34), were synthesized to study the effect of guanidium polymer length on delivery efficiency and toxicity. In addition, an N-acetyl-d-galactosamine (GalNAc)-based hydrophilic block was incorporated to produce diblock polymers, which provides a neutral hydrophilic block that sterically protects plasmid-polymer complexes (polyplexes) from colloidal aggregation and aids polyplex targeting to hepatocytes via binding to asialoglycoprotein receptors (ASGPRs)...
December 1, 2017: Bioconjugate Chemistry
Emilie Billaud, Sarah Belderbos, Frederik Cleeren, Wim Maes, Marlies Van de Wouwer, Michel Koole, Alfons Verbruggen, Uwe Himmelreich, Nick Geukens, Guy Bormans
In cancer research, pretargeted positron emission tomography (PET) imaging has emerged as an effective two-step approach that combines the excellent target affinity and selectivity of antibodies with the advantages of using short-lived radionuclides such as fluorine-18. One possible approach is based on the bioorthogonal inverse-electron-demand Diels-Alder (IEDDA) reaction between tetrazines and trans-cyclooctene (TCO) derivatives. Here, we report the first successful use of an 18F-labeled small TCO compound, [18F]1 recently developed in our laboratory, to perform pretargeted immuno-PET imaging...
November 30, 2017: Bioconjugate Chemistry
Ajmeeta Sangtani, Eleonora Petryayeva, Miao Wu, Kimihiro Susumu, Eunkeu Oh, Alan L Huston, Guillermo Lasarte-Aragones, Igor L Medintz, W Russ Algar, James B Delehanty
Nanoparticle (NP)-mediated drug delivery (NMDD) has emerged as a novel method to overcome the limitations of traditional systemic delivery of therapeutics, including the controlled release of the NP-associated drug cargo. Currently, our most advanced understanding of how to control NP-associated cargos is in the context of soft nanoparticles (e.g., liposomes), but less is known about controlling the release of cargos from the surface of hard NPs (e.g., gold NPs). Here we employ a semiconductor quantum dot (QD) as a prototypical hard NP platform and use intracellularly- triggered actuation to achieve spatiotemporal control of drug release and modulation of drug efficacy...
November 30, 2017: Bioconjugate Chemistry
Veronica Diaz-Rodriguez, Erh-Ting Hsu, Elena Ganusova, Elena Werst, Jeffrey Marvin Becker, Christine A Hrycyna, Mark D Distefano
Protein prenylation is a post-translational modification that involves the addition of one or two isoprenoid groups to the C-terminus of selected proteins using either farnesyl diphosphate or geranylgeranyl diphosphate. Three crucial enzymatic steps are involved in the processing of prenylated proteins to yield the final mature product. The farnesylated dodecapeptide, a-factor, is particularly useful for studies of protein prenylation because it requires the identical three step process to generate the same C-terminal farnesylated cysteine methyl ester substructure present in larger farnesylated proteins...
November 30, 2017: Bioconjugate Chemistry
Joshua J Santiana, Binglin Sui, Nicole Gomez, Jessica L Rouge
Herein we describe a modular assembly strategy for photo-cross-linking peptides into nucleic acid functionalized nanocapsules. The peptides embedded within the nanocapsules form discrete nanoscale populations capable of gating the release of molecular and nanoscale cargo using enzyme-substrate recognition as a triggered release mechanism. Using photocatalyzed thiol-yne chemistry, different peptide cross-linkers were effectively incorporated into the nanocapsules and screened against different proteases to test for degradation specificity both in vitro and in cell culture...
November 30, 2017: Bioconjugate Chemistry
Domenico Cassano, Salvador Pocoví-Martínez, Valerio Voliani
Currently, nanomaterials are of widespread use in daily commercial products. However, the most promising and potentially impacting application is in the medical field. In particular, nano-sized noble metals hold the promise to shift the current medical paradigms for the detection and therapy of neoplasms thanks to the: i) localized surface plasmon resonances (LSPRs), ii) high electron density, and iii) suitability for straightforward development of all-in-one nano-platforms. Nonetheless, there is still no clinically approved noble metal nanomaterial for cancer therapy/diagnostic...
November 29, 2017: Bioconjugate Chemistry
Maiko Miyazaki, Eiji Yuba, Hiroshi Hayashi, Atsushi Harada, Kenji Kono
For the enhancement of therapeutic effects and reduction of side effects derived from anticancer drugs in cancer chemotherapy, it is imperative to develop drug delivery systems with cancer-specificity and controlled release function inside cancer cells. pH-Sensitive liposomes are useful as an intracellular drug delivery system because of their abilities to transfer their contents into the cell interior through fusion or destabilization of endosome, which has weakly acidic environment. We earlier reported liposomes modified with various types of pH-sensitive polymers based on synthetic polymers and biopolymers as vehicles for intracellular drug delivery systems...
November 28, 2017: Bioconjugate Chemistry
Nicolas Alcaraz, Qingtao Liu, Eric Hanssen, Angus P R Johnston, Ben J Boyd
The combination of copper-free click chemistry with metabolic labelling offers new opportunities in drug delivery. The objective of this study was to determine whether cubosomes functionalised with azide or dibenzocyclooctyne (DBCO) groups are able to undergo copper-free click chemistry with a strained cyclooctyne or azide respectively. Phytantriol-based cubosomes were functionalised using phospholipids bearing an azide or DBCO group. The modified cubosome dispersions were characterized using dynamic light scattering, cryo-TEM and small angle X-ray scattering...
November 28, 2017: Bioconjugate Chemistry
Shuhao Zhang, Carolin Bisterfeld, Julia Bramski, Nane Vanparijs, Bruno G De Geest, Jörg Pietruszka, Alexander Böker, Stefan Reinicke
2-Deoxy-D-ribose-5-phosphate aldolase (DERA) is a biocatalyst that is capable of converting acetaldehyde and a second aldehyde as acceptor into enantiomerically pure mono- and diyhydroxyaldehydes, which are important structural motifs in a number of pharmaceutically active compounds. However, substrate as well as product inhibition requires more a sophisticated process design for the synthesis of these motifs. One way to do so is to couple aldehyde conversion with transport processes, which in turn would require an immobilization of the enzyme within a thin film that can be deposited on a membrane support...
November 28, 2017: Bioconjugate Chemistry
Dalu Chang, Ki Tae Kim, Eric Lindberg, Nicolas Winssinger
Nucleic acid templated reactions have attracted attention as an important technology to sense oligonucleotides and to translate nucleic acid-based instructions into diverse outputs. Great progresses have been made in accelerating the reaction in order to improve signal amplification, reaching rates where substrate turn-over rather than chemical reac-tion is rate limiting. Herein we explore the utility of architectures inspired by three-way junction that yield a cleav-age of a strand thus accelerating substrate turn-over...
November 27, 2017: Bioconjugate Chemistry
Yibo Zhou, Biwu Liu, Ronghua Yang, Juewen Liu
Using nanomaterials to mimic the function of protein enzymes is an interesting idea. Many nanomaterials have a similar size as enzymes and they also possess catalytic activities. Over the past decade, a surge of nanozyme work has emerged likely due to the advancement in the synthesis and characterization of inorganic nanoparticles. Many typical enzymatic reactions mimicking oxidases, peroxidases, laccases, superoxide dismutases, and catalases have been realized by simple metal oxide and metal nanoparticles...
November 26, 2017: Bioconjugate Chemistry
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"