Read by QxMD icon Read

Bioconjugate Chemistry

Wenming Ren, Jing-Jing Zhang, Cheng Peng, Huaijiang Xiang, Jingjing Chen, Chengyuan Peng, Weiliang Zhu, Ruimin Huang, Haiyan Zhang, Youhong Hu
Fluorescent imaging of β-amyloid (Aβ) is one of the most potential methods for Alzheimer's disease diagnosis. Several fluorescent probes have been reported to detect Aβ both in vitro and in vivo. However, high-sensitive and high-selective probes with low background signals are still highly urged. Here in, we rationally designed and synthesized a PIET quenched near-infrared probe QAD-1 to detect Aβ. This probe contains BODIPY as fluorophore and tetrahydroquinoxaline as the quenching group. QAD-1 exhibited significant fluorescent switch-on after binding to soluble and insoluble Aβ species, and the probe had the benefit of low background signal as staining Aβ plaques without the need of wash-out procedures in vitro which was specially found by fluorescence off-on probe...
September 6, 2018: Bioconjugate Chemistry
Marissa A Morales, Jeffrey Mark Halpern
Biosensors are powerful diagnostic tools defined as having a biorecognition element for analyte specificity and a transducer for a quantifiable signal. There are a variety of different biorecognition elements, each with unique characteristics. Understanding the advantages and disadvantages of each biorecognition element and their influence on overall biosensor performance is crucial in the planning stages to promote the success of novel biosensor development. Therefore, this review will focus on selecting the optimal biorecognition element in the preliminary design phase for novel biosensors...
September 14, 2018: Bioconjugate Chemistry
Qiqian Liu, Pasquale Sacco, Eleonora Marsich, Franco Furlani, Celia Arib, Nadia Djaker, Marc Lamy de la Chapelle, Ivan Donati, Jolanda Spadavecchia
Galectins (Gal) are a family of glycan-binding proteins characterized by their affinity for β-galactosides. Galectin-1(Gal-1), a dimeric lectin with two galactoside-binding sites, regulates cancer progression and immune responses. Coordination chemistry has been engaged to develop a versatile multivalent neoglycoconjugates for binding Gal -1.We report a simple and original method to synthesize hybrid gold nanoparticles in which a hydrochloride-lactose-modified chitosan, named Chitlac (CTL) is mixed to dicarboxylic acid-terminated polyethylene-glycol (PEG), leading to shell-like hybrid polymer-sugar-metal nanoparticles (CTL-PEG-AuNPs)...
September 14, 2018: Bioconjugate Chemistry
Wei Liu, Haitong Liu, Xiaoran Peng, Guoqiang Zhou, Dandan Liu, Shenghui Li, Jinchao Zhang, Shuxiang Wang
A novel anticancer theranostic prodrug, FDU-DB-NO2 , specifically activated by hypoxia for selective two-photon imaging hypoxia status, real-time tracking drug release, and solid tumor therapy was designed. The devised prodrug consists of an anticancer drug floxuridine (FDU), a fluorescence dye precursor 4'-(diethylamino)-1,1'-biphenyl-2-carboxylate (DB), and a hypoxic trigger 4-nitrobenzyl group. In normal cells, FDU-DB-NO2 is "locked". Whereas in tumor cells, the prodrug is "unlocked" by hypoxia and results in fluorescent dye 7-(diethylamino)coumarin (CM) generation along with FDU release...
September 14, 2018: Bioconjugate Chemistry
Jing Xia, Jinyun Wang, Xiang Wang, Ming Qian, Liuwei Zhang, Qixian Chen
Precision medicine requests preferential transportation of the pharmaceutical substances to the pathological site and impartation of localized therapeutic activities to the targeted cells. To accomplish this goal, we attempted a facile nanoscaled ultrasound-responsive delivery system, characterized by doxorubicin assembled with an amphiphilic copolymer (multiple of hydrophobic stearic segments tethered onto the hydrophilic pullulan backbone through ultrasound-labile oxyl-alkylhydroxylamine linkage). As a consequence of the strategically installed ultrasound-labile oxyl-alkylhydroxylamine linkage to elicit the tailored segregation of the hydrophilic pullulan and the hydrophobic stearic segments upon ultrasound impetus, the constructed nanoscaled self-assembly presented distinctive structural destabilization behaviors and afforded spatiotemporal controlled liberation of the cytotoxic drugs...
September 14, 2018: Bioconjugate Chemistry
T N Figueira, M T Augusto, K Rybkina, D Stelitano, M G Noval, O E Harder, A S Veiga, D Huey, C A Alabi, S Biswas, S Niewiesk, A Moscona, N C Santos, M A R B Castanho, M Porotto
The impact of influenza virus infection is felt each year on a global scale when approximately 5-10% of adults and 20-30% of children globally are infected. While vaccination is the primary strategy for influenza prevention, there are a number of likely scenarios for which vaccination is inadequate, making the development of effective antiviral agents of utmost importance. Anti-influenza treatments with innovative mechanisms of action are critical in the face of emerging viral resistance to the existing drugs...
September 14, 2018: Bioconjugate Chemistry
Zheng Ruan, Wei Miao, Pan Yuan, Liu Le, Lijuan Jiao, Erhong Hao, Lifeng Yan
NIR photosensitizer is attractive for photodynamic therapy (PDT). Low-power light irradiation and imaging-guided PDT makes it possible to increase tissue penetration depth. The pyrrole-substituted iodinated BODIPY (BDPI) molecule was designed and synthesized, and it possesses an intense NIR absorption and emission band, and exhibits a high singlet oxygen quantum yield (ΦΔ = 0.80) which leads remarkable cytotoxicity upon low power illumination (IC50 = 0.60 μg/mL, 6.1 mW/cm2 ). After being encapsulated with biocompatibility polypeptide PEG-PLys, polymeric micelles nanoparticles (PBDPI NPs) was obtained that are water-dispersed and passively tumor-targetable...
September 13, 2018: Bioconjugate Chemistry
Mays Al-Dulaymi, Deborah Michel, Jackson M Chitanda, Anas El-Aneed, Ronald E Verrall, Pawel Grochulski, Ildiko Badea
The unique molecular structure confers the diquaternary ammonium gemini surfactants with enhanced nucleic acid complexation ability, bottom-up design flexibility, and relatively low cytotoxicity. To capitalize on their potential as gene delivery vectors, novel structural modifications should be explored. In this work, 22 novel peptide-modified gemini surfactants with various alkyl tails and peptide spacer modifications were evaluated. This work represents the first report of dendrimer-like gemini surfactants and first evaluation of the impact of incorporating a hydrocarbon linker into the peptide chain...
September 13, 2018: Bioconjugate Chemistry
Ala Jo, June Sung, Sanghee Lee, Hyunsung Nam, Hyo Won Lee, Jongmin Park, Hwan Myung Kim, Eunha Kim, Seung Bum Park
Fluorescent tracers for glucose-uptake monitoring could be used as chemical tools for diagnosis and for discovery of novel therapeutic agents via the development of phenotypic screening systems. Here we present a new near-infrared fluorescent glucose tracer, Glc-SiR-CO2 H, for monitoring the cellular glucose uptake. By conjugating glucosamine with two different silicon rhodamine fluorochromes, we found that the net charge of fluorochromes has considerable effects on cellular uptake of the probe. Competition assay with d/l-glucose as well as Western blot analysis implied GLUT-dependent uptake mechanism of this probe...
September 12, 2018: Bioconjugate Chemistry
Thomas Müntener, Jérémy Kottelat, Annika Huber, Daniel Häussinger
Lanthanide chelating tags (LCTs) have been used with great success for determining structures and interactions of proteins and other biological macromolecules. Recently LCTs have also been used for in-cell NMR spectroscopy, but the bottleneck especially for demanding applications like pseudocontact shift (PCS) NMR is the sparse availability of suitable tags that allow for site-selective, rigid, irreversible, fast, and quantitative conjugation of chelated paramagnetic lanthanide ions to proteins via reduction stable bonds...
September 12, 2018: Bioconjugate Chemistry
Akello J Agwa, Linda V Blomster, David J Craik, Glenn F King, Christina I Schroeder
Gating modifier toxins from spider venom are disulfide-rich peptides that typically comprise a stabilizing inhibitor cystine knot (ICK). These knottin peptides are being pursued as therapeutic leads for a range of conditions linked to transmembrane proteins. Recently, double-knottin peptides discovered in spider venom and produced by recombinant expression have provided insights into the pharmacology of transmembrane channels. Here, we use chemoenzymatic ligation to produce double-knottins to probe the effect of bivalent modulation on the voltage-gated sodium channel subtype 1...
September 12, 2018: Bioconjugate Chemistry
Yongkang Gai, Lingyi Sun, Xiaoli Lan, Dexing Zeng, Guangya Xiang, Xiang Ma
Due to the increasing use of generator-produced radiometal Gallium-68 (68Ga) in positron-emission tomography/computed tomography (PET/CT), reliable bifunctional chelators that can efficiently incorporate 68Ga3+ into biomolecules are highly desirable. In this study, we synthesized two new bifunctional chelators bearing one or two phosphonic acid functional groups, named as p-SCN-PhPr-NE2A1P and p-SCN-PhPr-NE2P1A, with an aim of enabling facile production of 68Ga-based radiopharmaceuticals. Both chelators were successfully conjugated to LLP2A-PEG4, a very late antigen-4 (VLA-4) targeting peptidomimetic ligand, to evaluate their application in 68Ga-based PET imaging...
September 11, 2018: Bioconjugate Chemistry
Thayyath Sreenivasan Anirudhan, Syam S Nair
Gold nanoparticles (AuNP) have attracted ample attention as a transdermal (TND) drug delivery platform for improving the skin permeability of drug molecules. Herein a novel TND device formed from AuNP and oleylamine functionalized nanodiamond (AuD) has been developed successfully for the TND delivery of Ketoprofen (KP), a model drug. Polyvinyl alcohol/Polybuytl methacrylate (PVA/PBMA) film has selected as the matrix of the TND device, as they furnish excellent skin adhesion properties. The PVA/PBMA membranes loaded with different concentrations of AuD have been characterized in terms of surface morphology, thermomechanical properties, water vapor permeability (WVP), optical transmittance, cosmetic attractiveness, skin adhesion behavior and drug encapsulation efficiency (DEE)...
September 11, 2018: Bioconjugate Chemistry
Zhanfeng Hou, Chengjie Sun, Hao Geng, Kuan Hu, Mingsheng Xie, Yue Ma, Fan Jiang, Feng Yin, Zigang Li
A precisely positioned sulfimide chiral center on-tether of a thio-ether tethered peptide determines the peptide secondary structure by chemoselective oxaziridine modification. This method provides a facile way to tune peptides' secondary structures and biophysical properties.
September 11, 2018: Bioconjugate Chemistry
Jisoo Park, Yumi Lee, Byoung Joon Ko, Tae Hyeon Yoo
Conjugation of antibody has expanded its applications in therapeutics and diagnostics, and various methods have been developed based on chemical or enzymatic reactions. However, the majority of them have focused on synthetic molecules such as small molecules, nucleic acids, or synthetic materials, but site-specific conjugation of antibody with protein cargo has rarely been demonstrated. In this Communication, we report a PEptide-DIrected Photo-cross-linking (PEDIP) reaction for site-specific conjugation of IgG with protein using an Fc-binding peptide and a photoreactive amino acid analogue, and demonstrate this method by developing an immunotoxin composed of a Her2-targeting IgG (trastuzumab) and an engineered Pseudomonas exotoxin A (PE24)...
September 11, 2018: Bioconjugate Chemistry
Jianyue Feng, Qiang Luo, Yun Chen, Bing Li, Kui Luo, Jingbo Lan, Yunlong Yu, Shiyong Zhang
Herein, a new theranostic nanoplatform was built by introducing DOTA on the surface of the cross-linked small molecular micelles. This nanoplatform consisted of three parts: (1) Hydrophobic alkyl chain functioned with alkenes as cross-linkable part to ensure the robust stability in vivo; (2) Hydrophilic DOTA for not only gadolinium ions complexion as MR imaging contrast agents but also platinum ions complexion as drug carriers; (3) Cisplatin as antitumor drug and MR imaging amplifier simultaneously. The metal loading content of the resulting Pt/Gd@DOTA-CSMs was up to 12 wt% and 14 wt% for Gd(III) and Pt(II), respectively...
September 10, 2018: Bioconjugate Chemistry
Kate J F Carnevale, Geoffrey F Strouse
Covalently coupling nucleic acids to a gold nanoparticle (AuNP) surface has been demonstrated as an effective gene therapy agent to modify cellular protein expression. The therapeutic efficacy of the approach is anticipated to be impacted by the length of time the nucleic acid sequence resides in the endo-lysosomal pathway once transfected into a cell. It is believed that the dynamics of the processing should reflect the linkage chemistry of the DNA to the AuNP surface. In this manuscript the dynamics of nanotherapeutic uptake, nucleic acid release, and gene processing are investigated in vitro for a AuNP-nucleic acid delivery platform transfected into A375 human melanoma cells, as a function of the nucleic acid-gold linkage chemistry...
September 10, 2018: Bioconjugate Chemistry
Matthew W Rotz, Robert J Holbrook, Keith W MacRenaris, Thomas J Meade
We describe an entirely new, and vastly superior approach for labeling spherical nucleic acid conjugates (SNAs) with diagnostic probes (specifically optical and MR imaging agents). SNAs have been shown to combine the unique properties of Au-labeled nanoparticles and the DNA that is conjugated to the surface. Our previous work on preparing diagnostically labeled SNAs is labor intensive, relatively low yielding and costly. Here, we describe a straightforward and facile preparation for labeling SNAs with optical and MR imaging probes with significantly improved physical properties...
September 7, 2018: Bioconjugate Chemistry
Maxence Noel, Pierre-Andre Gilormini, Virginie Cogez, Cédric Lion, Christophe Biot, Anne Harduin-Lepers, Yann Guerardel
Mammalian sialyltransferases transfer sialic acids onto glycoproteins and glycolipids within the Golgi apparatus. Despite their key role in glycosylation, the study of their enzymatic activities is limited by the lack of appropriate tools. Herein, we developed a quick and sensitive sialyltransferase microplate assay based on the use of the unnatural CMP-SiaNAl donor substrate. In this assay an appropriate acceptor glycoprotein is coated on the bottom of 96-well plate and the sialyltransferase activity is assessed using CMP-SiaNAl...
September 7, 2018: Bioconjugate Chemistry
Yu Zhao, Zhentan Lu, Xiaomei Dai, Xiaosong Wei, Yunjian Yu, Xuelei Chen, Xinge Zhang, Chaoxing Li
Due to the rapid development of bacterial resistance, there is an urgent need to explore new antibacterial agents to substitute for traditional antibiotic therapy. Photodynamic therapy has been identified as a promising bactericidal method to conquer antibiotic-resistant pathogens. To solve the problem of photosensitizer damage to normal tissues in vivo, we developed a boron-dipyrrolemethene (BODIPY)-based glycosylated photosensitizer for ablating Pseudomonas aeruginosa ( P. aeruginosa). This glycosylated photosensitizer exhibited good water solubility and generated 1 O2 rapidly in an aqueous solution under light exposure...
September 7, 2018: 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"