China 
Africa 
Explore chapters and articles related to this topic
Material Properties for Biomedical Applications
Published in Savaş Kaya, Sasikumar Yesudass, Srinivasan Arthanari, Sivakumar Bose, Goncagül Serdaroğlu, Materials Development and Processing for Biomedical Applications, 2022
D. Ajith, K.G. Ashok, K. Aravind
The main advantage of scanning electron microscopy (SEM) is that sub-atomic resolutions (nano scale) can be obtained as compared to light microscopy. SEM is useful in determining not only the surface texture (coating evaluation, surface contaminations) of biomaterials, it can also be used for the cell structure or cell spreading on the surface of the biomaterial. To study the cell spreading on the material surface, the material is incubated in a cell culture plate with cell lines. At the end of the predetermined time, the material is retrieved from the cell culture plate, and it is treated in a serial dilution of alcohol so as to fix the cells adhering to its surface. Later, the sample surface is viewed under SEM at an appropriate magnification. The cell spreading gives us an idea of the affinity of the cells toward the scaffold (material).
Stem Cell Biology: An Overview
Published in Jyoti Ranjan Rout, Rout George Kerry, Abinash Dutta, Biotechnological Advances for Microbiology, Molecular Biology, and Nanotechnology, 2022
If the ESCs grow under suitable culture conditions, they continue to be undifferentiated (nonspecialized). However, when cells form embryoid bodies by growing as a clump of cells, they spontaneously differentiate. They can form different specialized cells like muscle cells, nerve cells, etc. Although spontaneous differentiation certainly indicates that embryonic stem cell culture is healthy, it is not controlled and, therefore, is an incompetent strategy to generate certain cell-type cultures. To create a culture of the precise kind of differentiated cells (e.g., cardiac muscle cells, blood cells, or nerve cells), scientists are modulating the differentiation of ESCs. They achieve this by altering the culture medium, modifying the cell culture plate or the cells by introducing certain genes (cloning). Years of experimentation have helped scientists establish the basic protocols for the targeted differentiation of ESCs to specific cell types.
Hazardous Materials—An Overview
Published in Gerald L. Schneberger, Adhesives in Manufacturing, 2018
Mutagens are materials which are capable of reacting with the genetic material of a living cell, deoxyribonucleic acid (DNA), to produce changes which are passed on in the heredity of the cell as it continues to divide. Such properties can be shown in laboratory tests that use bacteria or mammalian cells, such as the Ames Test, which uses a special mutant strain of Salmonella typhimurium that is not able to synthesize the essential amino acid histidine. When placed on a histidine-free culture plate, these bacteria do not grow. But if a mutagen is added which reverts the bacteria to histidine synthesizers, growth then occurs. This short-term test is useful because it correlates fairly well with chronic animal tests for carcinogens. Most materials which produce tumors or cancers in test animals also give a positive Ames Test; most materials which do not produce tumors or cancers in test animals, give a negative Ames Test.
Aptamerized silica/gold nanocapsules for stimulated release of doxorubicin through remote two-photon excitation
Published in International Journal of Smart and Nano Materials, 2022
Lih Shin Tew, Tsung-Hsi Lee, Leu-Wei Lo, Yit Lung Khung, Nai-Tzu Chen
The cytotoxicity profile of the GNS loaded with DOX toward MDA-MB-231 cells was evaluated using the cell meterTM colorimetric cell cytotoxicity assay kit (AAT Bioquest, Sunnyvale, CA, USA). In summary, MDA-MB-231 cells were cultured in 37°C with 5% CO2 and upon reaching 80% confluence, the cells were treated with trypsin after washing with PBS for 3 times. The detached cells were then centrifuged at 1000 rpm for 5 minutes, and the remaining cell pellets were re-suspended with pre-warmed growth medium before seeding on a new 96 well culture plate at a concentration of 1000 cells per well. After 24 hours incubation at 37°C, the cells were then exposed to gold nanoshell (GNS) loaded with DOX at a concentration of 25, 50, 75, and 100 µg/mL in serum free RPMI-1640. After 4 hours of incubation, the nanoparticles containing media were discarded and 100 µL of fresh medium was added into each well for another incubation period of 24 hours. Subsequently, 20 µL of cell meterTM assay solution was added into each well, and the solution was gently shaken for 30 seconds. The absorbance changes at 570 and 605 nm were then recorded with a microplate reader after another 4 hours of incubation, and the readings were used to determine for cell viability in each well.
Graphene oxide-driven interfacial coupling in laser 3D printed PEEK/PVA scaffolds for bone regeneration
Published in Virtual and Physical Prototyping, 2020
Pei Feng, Jiye Jia, Shuping Peng, Wenjing Yang, Shizhen Bin, Cijun Shuai
Scaffold specimens were sterilised with 70% ethanol and placed in culture medium for 12 h. MG63 cells were cultured in DMEM supplemented with 10% FBS and 1% penicillin/streptomycin at 37°C in a humidified atmosphere containing 5% CO2. A seeding density of 4 × 105 cells per specimen was applied for cell morphology studies. Specimens were rinsed with PBS and fixed with 2.5% glutaraldehyde for 12 h after incubation for 1, 3, 5 and 7 days. The fixed cells were washed with PBS three times, dehydrated in graded ethanol, and dried at 37°C for 4 h. Cell attachment on scaffolds was observed using SEM and cell relative area was quantified using PhotoShop software (Adobe Systems Inc.). Cell proliferation was assessed using a CCK-8 assay. 20 μl of CCK-8 reagent was added and incubated at 37°C for 4 h (He et al. 2019). The optical density was measured at λ = 450 nm to quantify the number of cells using a microplate reader. The cell culture plate without scaffold was set as control.
Titanium based mixed ligand complexes: Synthesis, spectroscopic and in vitro antiproliferative studies
Published in Inorganic and Nano-Metal Chemistry, 2018
Nitesh Kumar, Raj Kaushal, Ashun Chaudhary, Saroj Arora, Pamita Awasthi
The cytotoxic activity of the complexes was evaluated by using the colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay on HeLa, C6, and CHO cell lines. The assay was carried out in triplicate in 96 well plates following the well defined procedure with minor modifications[16]. The Cell pellet was resuspended in complete growth medium to get 1.5 × 105 cells/mL and 100 µL of cell suspension per well was seeded in tissue culture plate. Cells were treated with different concentrations of complexes and incubated for 12 h in CO2 incubator (37 °C, 5% CO2 and 90% relative humidity). After then, 20 µL of freshly prepared MTT solution (5 mg/mL in PBS, sterile filtered) was added to each well. Culture plates were gently stirred at 150 rpm for 5 min, to thoroughly mix the MTT into the media and then incubated for 4 h at 37 °C, to allow metabolization of MTT. MTT formazan crystals (MTT metabolic product) were resuspended in 100 µL of DMSO. After then, the plates were stirred for 20 min in order to dissolve formazan crystals and the OD was measured at 570 nm.