ABSTRACT
An image of fragmented sequence of biopolymer molecules by example of bacterial DNA in vivo (in atmosphere air) was received by scanning tunneling microscopy. An air adsorbate (mainly water vapors) that covers the molecule's surface gives rise to local tunnel conductivity and by virtue of adsorption selectivity indirectly reflects local conductance of fragments that consist of different rows of various atoms, supporting their tunnel conductivity. Having processed experimental data fragment images are obtained with scaled-up topography characteristics for their further identification.
Subject(s)
DNA, Bacterial/chemistry , DNA, Bacterial/ultrastructure , Microscopy, Scanning Tunneling/methodsABSTRACT
It was demonstrated that the three studied samples of carbon nanotubes of domestic production fixed on the substrate surface did not have toxic effect and could be used for cell cultivation. A biocompatible conductive coating based on carbon nanotubes and bovine serum albumin was developed. The efficacy of the coating for growing in vitro cell cultures was tested. A device was developed for electric stimulation of the cells. Local electric potential was applied to the cells using nanoscale electrodes. The results of human embryonic fibroblast cultivation in a pulsed electric field on conductive nanocomposite substrates were presented. An 26% increase in the proliferative activity of cells was observed at potentials up to 100 mV.
Subject(s)
Electric Stimulation , Nanotubes, Carbon , Serum Albumin, Bovine/chemistry , Animals , Biocompatible Materials/chemistry , Biocompatible Materials/toxicity , Cattle , Cell Line/drug effects , Cell Line/radiation effects , Cell Proliferation/drug effects , Cell Proliferation/radiation effects , Electricity , Fibroblasts/cytology , Fibroblasts/drug effects , Humans , Nanotubes, Carbon/chemistry , Nanotubes, Carbon/toxicityABSTRACT
The effects of single-walled and multiwalled carbon nanotubes on proliferative activity and viability of human embryo fibroblasts and glioblastoma cells were studied. Low cytotoxic activity of single-walled carbon tubes was demonstrated. Possible mechanisms of nanotube effects on cell growth are discussed.
Subject(s)
Fibroblasts/cytology , Glioblastoma/pathology , Materials Testing , Nanotubes, Carbon , Cell Proliferation , Cell Survival , Cells, Cultured , Embryo, Mammalian , HumansABSTRACT
The structure of biocompatible nanocomposites formed by the action of laser radiation on an aqueous dispersion of albumin with carbon nanotubes has been studied by the high-resolution methods of atomic force and transmitting electron microscopy. It has been shown that the nanocomposites have a bulky structure consisting of conglomerates of nanotubes uniformly distributed in the albumin matrix. The results of the study may be useful in the production of filling nanomaterials for implants of biological tissues and organs and the control of their quality.
