Biological activities and cellular uptake studies of fluorescent derivatives of indole alkaloid tumor promoter teleocidin

A series of novel 1, 3, 4-oxadiazole analogues was synthesized from cyclization of hydrazones of substituted 1-ethyl-1,4-dihydro-7-methyl-4-oxo-1,8-naphthyridine-3-carbohydrazides were prepared from nalidixic acid. The structures of synthesized oxadiazole derivatives and their copper complexes were elucidated on the basis of FTIR, elemental analyses, 1H-NMR and atomic absorption spectral analysis. It was observed from spectral data that metal ligand ratio was 1:1 in all copper complexes and they were bidentate, coordination was found to be done through oxygen of 4-oxo group and nitrogen of oxadiazole ring. The synthesized compounds were further evaluated with biological activities and compared with parent hydrazones. Copper complexes possess antibacterial and antifungal activities better than the oxadiazoles while they have better antioxidant activity then copper complexes. Parent hydrazones were better in all biological activities than synthesized oxadiazoles.

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In Vitro Cellular Uptake Studies of Self-Assembled Fluorinated Nanoparticles Labelled with Antibodies

Nanomaterials ◽

10.3390/nano11081906 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1906

Author(s):

Mona Atabakhshi-Kashi ◽

Mónica Carril ◽

Hossein Mahdavi ◽

Wolfgang J. Parak ◽

Carolina Carrillo-Carrion ◽

...

Keyword(s):

Flow Cytometry ◽

Cellular Uptake ◽

Hydrophobic Interactions ◽

Intrinsic Properties ◽

Wide Range ◽

Self Assembled ◽

Uptake Studies ◽

Targeting Ability ◽

Fluorinated Nanoparticles

Nanoparticles (NPs) functionalized with antibodies (Abs) on their surface are used in a wide range of bioapplications. Whereas the attachment of antibodies to single NPs to trigger the internalization in cells via receptor-mediated endocytosis has been widely studied, the conjugation of antibodies to larger NP assemblies has been much less explored. Taking into account that NP assemblies may be advantageous for some specific applications, the possibility of incorporating targeting ligands is quite important. Herein, we performed the effective conjugation of antibodies onto a fluorescent NP assembly, which consisted of fluorinated Quantum Dots (QD) self-assembled through fluorine–fluorine hydrophobic interactions. Cellular uptake studies by confocal microscopy and flow cytometry revealed that the NP assembly underwent the same uptake procedure as individual NPs; that is, the antibodies retained their targeting ability once attached to the nanoassembly, and the NP assembly preserved its intrinsic properties (i.e., fluorescence in the case of QD nanoassembly).

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Synthesis, Antiproliferative Activity and Radical Scavenging Ability of 5-O-Acyl Derivatives of Quercetin

Molecules ◽

10.3390/molecules26061608 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1608

Author(s):

Stephen Lo ◽

Euphemia Leung ◽

Bruno Fedrizzi ◽

David Barker

Keyword(s):

Antiproliferative Activity ◽

Biological Activities ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Breast Cancer Cell Lines ◽

Scavenging Activity ◽

Plant Materials ◽

Wide Range ◽

Derivatives Of ◽

Acyl Derivatives

Quercetin is a flavonoid that is found in many plant materials, including commonly eaten fruits and vegetables. The compound is well known for its wide range of biological activities. In this study, 5-O-acyl derivatives of quercetin were synthesised and assessed for their antiproliferative activity against the HCT116 colon cancer and MDA-MB-231 breast cancer cell lines; and their radical scavenging activity against the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical species. Four derivatives were found to have improved the antiproliferative activity compared to quercetin whilst retaining radical scavenging activity.

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EFFECTS OF POLYMERIC NANOPARTICLE SURFACE PROPERTIES ON INTERACTION WITH BRAIN TUMOR ENVIRONMENT

Nano LIFE ◽

10.1142/s1793984413430034 ◽

2013 ◽

Vol 03 (04) ◽

pp. 1343003 ◽

Cited By ~ 7

Author(s):

BRANDON MATTIX ◽

THOMAS MOORE ◽

OLGA UVAROV ◽

SAMUEL POLLARD ◽

LAUREN O'DONNELL ◽

...

Keyword(s):

Human Brain ◽

Surface Charge ◽

Cellular Uptake ◽

Drug Clearance ◽

Cellular Interaction ◽

Normal Tissues ◽

Poly Ethylene ◽

Uptake Studies ◽

Effect Of Surface

Current chemotherapy treatments are limited by poor drug solubility, rapid drug clearance and systemic side effects. Additionally, drug penetration into solid tumors is limited by physical diffusion barriers [e.g., extracellular matrix (ECM)]. Nanoparticle (NP) blood circulation half-life, biodistribution and ability to cross extracellular and cellular barriers will be dictated by NP composition, size, shape and surface functionality. Here, we investigated the effect of surface charge of poly(lactide)-poly(ethylene glycol) NPs on mediating cellular interaction. Polymeric NPs of equal sizes were used that had two different surface functionalities: negatively charged carboxyl ( COOH ) and neutral charged methoxy ( OCH 3). Cellular uptake studies showed significantly higher uptake in human brain cancer cells compared to noncancerous human brain cells, and negatively charged COOH NPs were uptaken more than neutral OCH 3 NPs in 2D culture. NPs were also able to load and control the release of paclitaxel (PTX) over 19 days. Toxicity studies in U-87 glioblastoma cells showed that PTX-loaded NPs were effective drug delivery vehicles. Effect of surface charge on NP interaction with the ECM was investigated using collagen in a 3D cellular uptake model, as collagen content varies with the type of cancer and the stage of the disease compared to normal tissues. Results demonstrated that NPs can effectively diffuse across an ECM barrier and into cells, but NP mobility is dictated by surface charge. In vivo biodistribution of OCH 3 NPs in intracranial tumor xenografts showed that NPs more easily accumulated in tumors with less collagen. These results indicate that a robust understanding of NP interaction with various tumor environments can lead to more effective patient-tailored therapies.

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