Purpose: To evaluate the cytotoxicity, permeation, and transport mechanisms of PAMAM dendrimers and surface-modified cationic PAMAM dendrimers using monolayers of the human colon adenocarcinoma cell line, Caco-2.
Methods: Cytotoxicity was determined using the MTT assay. The effect of dendrimers on monolayer integrity was determined from measurements of transepithelial electrical resistance (TEER) and [14C]mannitol apparent permeability coefficient (Papp). The Papp of dendrimers through monolayers was measured in both the apical (A)-to-basolateral (B) and B --> A directions at 4 degrees C and 37 degrees C and also in the presence and absence of ethylenediamine tetraacetic acid (EDTA) and colchicine.
Results: The cytotoxicity and permeation of dendrimers increased with both concentration and generation. The cytotoxicity of cationic dendrimers (G2, G3, G4) was greater than that of anionic dendrimers (G2.5, G3.5) but was reduced by conjugation with lauroyl chloride: the least cytotoxic conjugates were those with six attached lauroyl chains. At 37 degrees C the Papp of cationic dendrimers was higher than that of anionic dendrimers and, in general, increased with the number of attached lipid chains. Cationic dendrimers decreased TEER and significantly increased the Papp of mannitol. Modified dendrimers also reduced TEER and caused a more marked increase in the Papp of mannitol. The Papp values of dendrimers and modified dendrimers were higher in the presence of EDTA, lower in the presence of colchicine, and lower at 4 degrees C than at 37 degrees C.
Conclusions: The properties of dendrimers may be significantly modified by surface engineering. Conjugation of cationic PAMAM dendrimers with lauroyl chloride decreased their cytotoxicity and increased their permeation through Caco-2 cell monolayers. Both PAMAM dendrimers and lauroyl-PAMAM dendrimer conjugates can cross epithelial monolayers by paracellular and transcellular pathways.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1023/a:1026166729873 | DOI Listing |
J Am Chem Soc
January 2025
Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States.
The use of proteins as intracellular probes and therapeutic tools is often limited by poor intracellular delivery. One approach to enabling intracellular protein delivery is to transform proteins into spherical nucleic acid (proSNA) nanoconstructs, with surfaces chemically modified with a dense shell of radially oriented DNA that can engage with cell-surface receptors that facilitate endocytosis. However, proteins often have a limited number of available reactive surface residues for DNA conjugation such that the extent of DNA loading and cellular uptake is restricted.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Interdisiplinary program in Genetics and Genomics, Texas A&M University, College Station, TX, 77843, USA.
Organelles are specialized subunits within cells which carry out vital functions crucial to cellular survival and form a tightly regulated network. Dysfunctions in any of these organelles are linked to numerous diseases impacting virtually every organ system in the human body. Targeted delivery of therapeutics to specific organelles within the cell holds great promise for overcoming challenging diseases and improving treatment outcomes through the minimization of therapeutic dosage and off-target effects.
View Article and Find Full Text PDFSci Rep
January 2025
Laser Research Centre, Faculty of Health Science, University of Johannesburg, Doornfontein, 2028, South Africa.
The simultaneous administration of multiple drugs within identical nanocarriers to cancer cells or tissues can result in the effective action of drugs at reduced concentrations. In this investigation, PAMAM dendrimers (G4-PAMAM) were employed to link with methotrexate (MTX) using DCC/NHS chemistry and followed by the entrapment of curcumin (Cur) within it. The establishment of covalent bonds between MTX and the PAMAM dendrimer led to PAMAM-MTX interaction, verified and described through FT-IR.
View Article and Find Full Text PDFTalanta
January 2025
Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences & Chongqing School, University of Chinese Academy of Science, Chongqing, 400714, PR China. Electronic address:
Polymers and dendrimers are macromolecules, possessing unique and intriguing characteristics, that are widely applied in self-assembled functional materials, green catalysis, drug delivery and sensing devices. Traditional approaches for the structural characterization of polymers and dendrimers involve DLS, GPC, NMR, IR and TG, which provide their physiochemical features and ensemble information, whereas their unimolecular conformation and dispersion also are key features allowing to understand their transporting profile in confined ionic nanochannels. This work demonstrates the nanopore approach for the determination of charged homopolymers, neutral block copolymer and dendrimers under distinct bias potentials and pH conditions.
View Article and Find Full Text PDFBiomater Sci
January 2025
Department of Biological Sciences and Engineering Indian Institute of Technology, Palaj, Gandhinagar 382355, India.
The application of nanotechnology in medical biology has seen a significant rise in recent years because of the introduction of novel tools that include supramolecular systems, complexes, and composites. Dendrimers are one of the remarkable examples of such tools. These spherical, regularly branching structures with enhanced cell compatibility and bioavailability have shown to be an excellent option for gene or drug administration.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!