Abstract:
:We present a tool for dispensing very low volumes (20 nL or more) of ultra high viscosity (UHV) medical-grade alginate hydrogels. It uses a modified piezo-driven micrometering valve, integrated into a versatile system that allows fast prototyping of encapsulation procedures and scaffold production. Valves show excellent dispensing properties for UHV alginate in concentrations of 0.4% and 0.7% and also for aqueous liquids. An optimized process flow provides excellent handling of biological samples under sterile conditions. This technique allows the encapsulation of adherent cells and structuring of substrates for biotechnology and regenerative medicine. A variety of cell lines showed at least 70% viability after encapsulation (including cell lines that are relevant in regenerative medicine like Hep G2), and time-lapse analysis revealed cells proliferating and showing limited motility under alginate spots. Cells show metabolic activity, gene product expression, and physiological function. Encapsulated cells have contact with the substrate and can exchange metabolites while being isolated from macromolecules in the environment. Contactless dispensing allows structuring of substrates with alginate, isolation and transfer of cell-alginate complexes, and the dispensing of biological active hydrogels like extracellular matrix-derived gels.
journal_name
Biotechniquesjournal_title
BioTechniquesauthors
Gepp MM,Ehrhart F,Shirley SG,Howitz S,Zimmermann Hdoi
10.2144/000113014subject
Has Abstractpub_date
2009-01-01 00:00:00pages
31-2, 34, 36-8 passimissue
1eissn
0736-6205issn
1940-9818journal_volume
46pub_type
杂志文章相关文献
BIOTECHNIQUES文献大全abstract::A brief description of the setup of an inexpensive densitometric analysis system is provided. This system uses a software package and scanner that can be obtained for a total of less than $1000 and that can be operated by any Macintosh computer, including a MacPlus. In the event that a scanner is already available, th...
journal_title:BioTechniques
pub_type:
doi:
更新日期:1994-06-01 00:00:00
abstract::A rapid and inexpensive method for isolating bacterial DNA for use in PCR is described. The method is based on the guanidinium thiocyanate (GuSCN)-lysis method of Boom et al. (J. Clin. Microbiol. 28:495-503, 1990) and enables a multiple of 96 samples to be prepared in only one hour. We use Multiscreen plates and a vac...
journal_title:BioTechniques
pub_type: 杂志文章
doi:
更新日期:1995-08-01 00:00:00
abstract::Ribosome profiling is a powerful tool for characterizing in vivo protein translation at the genome scale, with multiple applications ranging from detailed molecular mechanisms to systems-level predictive modeling. Though highly effective, this intricate technique has yet to become widely used in the microbial research...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/000114302
更新日期:2015-06-01 00:00:00
abstract::We have designed and implemented a system to manage whole genome shotgun sequences and whole genome sequence assembly data flow. The Sequence Assembly Manager (SAM) consists primarily of a MySQL relational database and Perl applications designed to easily manipulate and coordinate the analysis of sequence information ...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/05385ST01
更新日期:2005-05-01 00:00:00
abstract::The study of gene regulation in cardiac myocytes requires a reliable in vitro model. However, monolayer cultures used for this purpose are typically not exposed to electrical stimulation, though this has been shown to strongly affect cardiomyocyte gene expression. Based on pacemakers for clinical use, we developed an ...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/000113308
更新日期:2010-01-01 00:00:00
abstract::We investigated the ability of an amphipathic oligopeptide to carry a synthetic dsDNA oligonucleotide inside human cells. The oligonucleotide was designed as a decoy binding site for the transcriptional activator of the methylguanine-DNA methyltransferase (MGMT) gene. The complex oligopeptide and decoy were administer...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/02321dd03
更新日期:2002-01-01 00:00:00
abstract::In this communication we describe the sequential use of standard and low-melting agarose in a single gel slab for the electrophoresis of DNA. This method has the advantages of high resolution and reproducibility characteristic of standard agarose and the ease of manipulation of DNA for direct cloning, sequential diges...
journal_title:BioTechniques
pub_type: 杂志文章
doi:
更新日期:1991-02-01 00:00:00
abstract::Cell culture is a vital component of laboratories throughout the scientific community, yet the absence of standardized protocols and documentation practice challenges laboratory efficiency and scientific reproducibility. We examined the effectiveness of a cloud-based software application, CultureTrax® as a tool for st...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/btn-2018-0062
更新日期:2018-11-01 00:00:00
abstract::Recombinant alphaviruses have been used as vehicles for delivery and expression of heterologous genes in mammalian, avian and insect cell lines. We have used a Sindbis replicon virus (Sinreplac) able to express the E. coli lacZ gene to compare the efficiency of transduction in one insect, six mammalian cell lines and ...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/96213rr02
更新日期:1996-09-01 00:00:00
abstract::Stable cell transfection is used for the expression of exogenous genes or cDNAs in eukaryotic cells. Selection of these transfectants requires a dominant selectable marker. A variety of such markers has been identified and is currently in use. However, many of these are not suitable for all cell types or require uniqu...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/03346st05
更新日期:2003-06-01 00:00:00
abstract::An improved method was developed for in situ reverse transcription-polymerase chain reaction (RT-PCR) to detect and localize mRNA in tissue sections. The coverslip mounted-immersion cycled (COSMIC) in situ RT-PCR technique combines the advantages of solution-phase PCR with the tissue immobilization necessary for in si...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/98241st02
更新日期:1998-01-01 00:00:00
abstract::A technique that can be used to isolate vector/insert junctions from clones in vectors, such as yeast artificial chromosomes and P1s, and to sequence plasmid inserts more rapidly has been developed. A vector primer is combined with single, randomly chosen oligonucleotides in PCRs, to create pools of products. With 12-...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/19962003486
更新日期:1996-03-01 00:00:00
abstract::We report a modification of a liquid hybridization method that serves as a rapid, sensitive alternative to Southern hybridization for the analysis of polymerase chain reaction (PCR) products. An aliquot of the completed PCR is mixed with an internally nested, end-labeled oligonucleotide probe, and one cycle of PCR is ...
journal_title:BioTechniques
pub_type: 杂志文章
doi:
更新日期:1991-01-01 00:00:00
abstract::Fluorescent dye terminator Sanger sequencing (FTSS), with detection by automated capillary electrophoresis (CE), has long been regarded as the gold standard for variant detection. However, software analysis and base-calling algorithms used to detect mutations were largely optimized for resequencing applications in whi...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/000113913
更新日期:2012-09-01 00:00:00
abstract::Transfection experiments involving mixed cell cultures pose special problems because of differential uptake and expression of DNA by different cell types. In order to evaluate the expression of transfected DNA in primary cultures of embryonic myocardial cells, we have used immunofluorescence microscopy to analyze expr...
journal_title:BioTechniques
pub_type: 杂志文章,评审
doi:
更新日期:1988-07-01 00:00:00
abstract::Genome variation provides researchers with thousands of markers with which to study human demographic history and phenotypes. Insertion-deletion (indel) polymorphism is an important and abundant form of human genome variation, and convenient methods for genotyping indels are therefore needed. Here we evaluate dynamic ...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/03352st01
更新日期:2003-08-01 00:00:00
abstract::We describe the application of simple cloning by prolonged overlap extension for multiple site-directed mutagenesis in the same plasmid. We show that it is possible to use this technique with very short PCR templates. The technique is ideally suited for the generation of longer donor DNA sequences for CRISPR/Cas9-medi...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/btn-2019-0104
更新日期:2020-06-01 00:00:00
abstract::Cytokines are pivotal to a balanced innate or cell-mediated immune response, can be indicative of disease progression and/or resolution, and are being evaluated as therapeutics. There is a need to purify and/or to measure key cytokines rapidly with accuracy, precision, and sensitivity. The current assay technologies, ...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/02321dd02
更新日期:2002-01-01 00:00:00
abstract::Biopharmaceutical products are of great importance in the treatment or prevention of many diseases and represent a growing share of the global pharmaceutical market. The usual technology for protein synthesis (cell-based expression) faces certain obstacles, especially with 'difficult-to-express' proteins. Cell-free pr...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/btn-2020-0155
更新日期:2021-01-20 00:00:00
abstract::Several DNA extraction methods have been reported for use with digesta or fecal samples, but problems are often encountered in terms of relatively low DNA yields and/or recovering DNA free of inhibitory substances. Here we report a modified method to extract PCR-quality microbial community DNA from these types of samp...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/04365ST04
更新日期:2004-05-01 00:00:00
abstract::We have generated a genomic P1 bacteriophage library using Monterey pine (Pinus radiata) DNA. We first developed a method for isolating from pine tissue the very high molecular weight DNA necessary for the preparation of libraries requiring large inserts. The method involves protoplasting the cells, isolating nuclei a...
journal_title:BioTechniques
pub_type: 杂志文章
doi:
更新日期:1992-05-01 00:00:00
abstract::The ZEBRA protein is a transcriptional activator that induces expression of viral lytic genes in cells harboring latent Epstein-Barr virus (EBV). In this report it is shown that a derivative of ZEBRA that cannot activate transcription (Zd) can be used to detect and characterize activation domains. Three expression vec...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/97225rr02
更新日期:1997-05-01 00:00:00
abstract::Another method has been developed to attach synthetic peptides to solid supports for use in enzyme immunoassays. The method is based on passively adsorbing a synthetic peptide to a solid-phase support, then further attaching more of the same peptide by means of cross-linking to the previously adsorbed peptide. This me...
journal_title:BioTechniques
pub_type: 杂志文章
doi:
更新日期:1992-11-01 00:00:00
abstract::Genomic analysis of circulating, cell-free DNA (cfDNA) is being used extensively for molecular diagnostics. Many approaches rely on the construction of cfDNA genomic libraries, targeted retrieval of specific genomic regions and analysis by next-generation DNA sequencing. Several steps during sample preparation require...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/btn-2019-0071
更新日期:2019-10-01 00:00:00
abstract::Microarray expression analysis has become one of the most widely used functional genomics tools. Efficient application of this technique requires the development of robust and reproducible protocols. We have optimized all aspects of the process, including PCR amplification of target cDNA clones, microarray printing, p...
journal_title:BioTechniques
pub_type: 杂志文章,评审
doi:10.2144/00293bi01
更新日期:2000-09-01 00:00:00
abstract::3D printed biomaterials are increasingly used in cell cultures and drug screens. Given the ease of creating artificial tissues, will this technique revolutionize biomedicine and organ implants in the future? ...
journal_title:BioTechniques
pub_type: 新闻
doi:10.2144/btn-2017-0113
更新日期:2018-03-01 00:00:00
abstract::We describe a rapid and sensitive method for the detection of nucleotide sequence variation that can be used for large-scale screening of population markers. Denaturing gradient gel electrophoresis (DGGE) detects sequence variants of amplified fragments by the differences in their melting behavior. DGGE detects most s...
journal_title:BioTechniques
pub_type: 杂志文章
doi:10.2144/99275rr02
更新日期:1999-11-01 00:00:00
abstract::Several techniques were evaluated for the quantitation of the total protein content of an IgG2a monoclonal antibody, KS1/4, and its deacetylvinblastine (DAVLB) conjugate. The UV assay is rapid, but it requires an extensive calibration of the response factor, and impurities may cause a high bias. Amino acid analysis (A...
journal_title:BioTechniques
pub_type: 杂志文章
doi:
更新日期:1988-11-01 00:00:00
abstract::Perfluorocarbon emulsions were applied to hybridoma cultures grown in tissue culture tubes and column bioreactors. The oxygen transfer enhancement effect of perfluorocarbon emulsions was clearly demonstrated by the higher cell densities obtained in emulsion-supplemented systems. In addition, perfluorocarbon emulsions ...
journal_title:BioTechniques
pub_type: 杂志文章
doi:
更新日期:1992-02-01 00:00:00
abstract::Radiolabeled proteins are used in a variety of laboratory applications as well as in radioimmunotherapy. This review focuses on methods that utilize genetic engineering to introduce exogenous phosphorylation sites into proteins. Protein kinase substrate sites can be introduced into target proteins to serve as tags for...
journal_title:BioTechniques
pub_type: 杂志文章,评审
doi:
更新日期:2002-10-01 00:00:00