Microfabrication and application of reservoir pins for liquid transfer in biotechnology

Microarraying involves laying down genetic elements onto a solid substrate for DNA analysis on a massively parallel scale. Microarrays are prepared using a pin-based robotic platform to transfer liquid samples from microtitre plates to an array pattern of dots of different liquids on the surface of glass slides where they dry to form spots diameter < 200 μm. This paper presents the design, materials selection, micromachining technology and performance of reservoir pins for microarraying. A conical pin is produced by (i) conventional machining of stainless steel or wet etching of tungsten wire, followed by (ii) micromachining with a focused laser to produce a microreservoir and a capillary channel structure leading from the tip. The pin has a flat end diameter < 100 μm from which a 500 μm long capillary channel < 15 μm wide leads up the pin to a reservoir. Scanning electron micrographs of the metal surface show roughness on the scale of 10 μm, but the pins nevertheless give consistent and reproducible spotting performance. The pin capacity is 80 nanolitres of fluid containing DNA, and at least 50 spots can be printed before replenishing the reservoir. A typical robot holds can hold up to 64 pins. This paper discusses the fabrication technology, the performance and spotting uniformity for reservoir pins, the possible limits to miniaturization of pins using this approach, and the future prospects for contact and non-contact arraying technology.

Bioethics and biotechnology

This paper examines the practice and products of biotechnology from the viewpoint of bioethics, looking at four cases where aquatic biotechnology and bioethics intersect. The four cases applied are: Case 1. Genetic modification of animals; Case 2. Genetically Modified Organisms (GMO) as food; Case 3. Environmental applications of GMOs; Case 4. Intellectual property production for GMOs and DNA sequences.

The review of recent advances in fish genetics and biotechnology

Great advances have been, and are being made in our knowledge of the genetics and molecular biology (including genomics, proteomics and structural biology). Global molecular profiling technologies such as microassays using DNA or oligonucleotide chip, and protein and lipid chips are being developed. The application of such biotechnological advances are inevitable in aquaculture in the areas of improvement of aquaculture stocks where many molecular markers such as RFLPs, AFLDs and RAPD are now available for genome analysis, finger printing and genetic linkage mapping. Transgenic technology has been developed in a number of fish species and research is being pursed to produce transgenic fish carrying genes that encode antimicrobial peptides such as lysozyme thereby achieving disease resistance in fish. Also it is a short cut to achieving genetic change for fast growth and other desirable traits like early sexual maturity, temperature tolerance and feed conversion efficiency. KEYWORDS: Fish genetics, transgenesis, monoploidy, diploidy, polyploidy,gynogenesis, androgenesis, cryopreservation.

Biotechnology: in Great Britain

The general perception of this new 'industry' is one of high-powered science breaking the frontiers of knowledge. At the same time, there is a good deal of haziness about what biotechnology is, where it is done, and by whom. This article discusses the evolution of biotechnology, then outlines the industry as it exists in Britain today. The next section considers what are some of the most important locational considerations for firms and gives both a snapshot for the country as a whole and a more detailed picture for one area, that around Cambridge. Finally, comments on aspects of the industry's possible future development. -from Authors

Fish ES cells and applications to biotechnology

ES cells provide a promising tool for the generation of transgenic animals with site-directed mutations. When ES cells colonize germ cells in chimeras, transgenic animals with modified phenotypes are generated and used either for functional genomics studies or for improving productivity in commercial settings. Althought the ES cell approach has been limited to, mice, there is strong interest for developing the technology in fish.. We describe the step-by-step procedure for developing ES cells in fish. Key aspects include avoiding cell differentiation, specific in vitro traits of pluripotency, and, most importantly, testing for production of chimeric animals as the main evidence of pluripotency. The entire process focuses on two model species, zebrafish and medaka, in which most work has been done. The achievements attained in these species, as well as their applicability to other commercial fish, are discussed. Because of the difficulties relating to germ line competence, mostly of long-term fish ES cells, alternative cell-based approaches such as primordial germ cells and nuclear transfer need to be considered. Although progress to date has been slow, there are promising achievements in homologous recombination and alternative avenues yet to be explored that can bring ES technology in fish to fruition.

Molecular biotechnology of marine algae in China

Molecular biotechnology of marine algae is referred to as the biotechnology on the identification, modification, production and utilization of marine algal molecules. It involves not only the manipulation of macromolecules such as DNA, RNA and proteins, but also deals with low molecular weight compounds such as secondary metabolites. In the last decade, molecular systematic researches to investigate the relationship and to examine the evolutionary divergence among Chinese marine algae have been carried out by Chinese scientists. For example, RAPD has been widely used in several laboratories to elucidate genetic variations of the reds, such as Porphyra, Gracilaria, Grateloupia and the greens such as Ulva and Enteromorpha. Some important data have been obtained. The study on molecular genetic markers for strain improvement is now in progress. In 1990s, genetic engineering of economic seaweeds such as Laminaria, Undaria, Porphyra, Gracilaria and Grateloupia has been studied in China. For Laminaria japonica, the successfully cultivated kelp in China, a model transformation system has been set up based on the application of plant genetic techniques and knowledge of the algal life history. Progress has been made recently in incorporating a vaccine gene into kelp genome. Evidence has been provided showing the expression of gene products as detectable vaccines. In the present paper, the progress of molecular biotechnological studies of marine algae in China, especially researches on elucidating and manipulating nucleic acids of marine algae, are reviewed.

Algal biotechnology industries and research activities in China

In old China there were very few people engaged in the study of the algae, but in new China, freshwater and marine algae are studied by over one hundred old and new phycologists. There is now an algal biotechnology industry consisting of an aquaculture industry, producing large amounts of the seaweeds Laminaria, Porphyra, Undaria, Gracilaria, eucheumoids, and the microalgae Dunaliella and Spirulina. There is also a phycocolloid industry, producing algin, agar and carrageenan; an industry producing chemicals and drugs, such as iodine, mannitol, phycocyanin, beta -carotene, PSS (propylene glycol alginate sulfate) and FPS (fucose-containing sulfated polysaccharides) and an industry producing food, feed and fertilizer. The Laminaria cultivation industry produces about 900,000 t dry Laminaria, probably the largest producer in the world and 13,000 t algin, undoubtedly one of the largest algin producer in the world.

An inquiry-based learning (IBL) approach to molecular biology for biotechnology undergraduate students

Sin índice de impacto (2013)