Shopping on line can be easy, simple and save you lots of money. It can also take a lot of your time, frustrate you, and result in unwanted purchases. Now the same can be said for regular high street shopping, but with the vast opportunity presented by the Internet it will pay you to spend a few minutes reading this and understanding how to better optimize your Spider Silk shopping experience:

1. Compare - without doubt the biggest advantage that the Spider Silk offers shoppers today is the ability to compare thousands of Spider Silk at a time. This is a great thing, but not necessarily all the time! Too much can be daunting at times so take advantage of the great comparison sites and where possible let them do the hard work for you.

2. Research - if it has been said it will be on the internet. Ignorance is no longer a justifiable reason for buying the wrong thing. Take the time to research in detail everything that you could possible want to know about

3. Testimonials - don't know anybody that has bought a Spider Silk? Wrong! If the Spider Silk is good the internet will let you know. Use the Internet as a friend and get testimonials before you buy.

4. Questions - Got a question about Spider Silk then search the Forums, FAQ's, Blogs etc. Don't be afraid to ask .....

5. Reputation - Never heard of the company selling Spider Silk? Don't worry, no reason why you should know every company in the world, but you know someone that does! Use the internet to find out what people are saying about Spider Silk and build up a picture of their reputation for sales, returns, customer service, delivery etc.

6. Returns - still worried that even after all of the above your Spider Silk wont be what you want? Check out the returns policy. There is so much competition now that someone, somewhere is bound to offer the terms that you are comfortable with.

7. Feedback - happy with your Spider Silk then let people know, after all you are depending on others people input in your buying decision, so why not give a little back.

8. Security - check for the yellow padlock on the Spider Silk site before you buy, and the s after http:/ /i.e. https:// = a secure site

9. Contact - got a question about Spider Silk, or want to leave a comment then check out the sites contact page. Reputable companies have them and respond.

10. Payment - ready to pay for your Spider Silk, then use your credit card or PayPal! Be aware of companies that don't accept them, there may be genuine reasons but given the huge amount of choice you have when buying online there is no reason at all not to buy via credit card or PayPal.

Spider silk, also known as gossamer, is a fiber spun by spiders.Spider silk is a remarkably strong material. Its tensile strength is comparable to that of high-grade steel — according to Nature (journal), spider dragline silk has a tensile strength of roughly 1.3 Pascal (unit), while one source [http://www.geocities.com/pganio/materials.html lists a tensile strength for one form of steel at 1.65 GPa. However, spider silk is much less dense than steel; its tensile strength to density ratio is roughly five times higher than that of [steel (i.e. it is five times as strong as steel of the same density — as strong as [Aramid filaments, such as [Twaron or [Kevlar.) In fact, a strand of spider silk long enough to circle the earth would weigh less than 16 [ounces (450 [gram).

Usage wraps her prey in silk. Spiders normally use their silk to make structures, either for protection for their offspring, or for predation on other creatures. They can also suspend themselves using their silk, normally for the same reasons.

The trapdoor spider will burrow into the ground and weave a trapdoor-like structure with spindles around so it can tell when prey arrives and take it by surprise.

Many small spiders use silk threads for ballooning (spider). They extrude several threads into the air and let themselves become carried away with upward winds. Although most rides will end a few meters later, it seems to be a common way for spiders to invade islands. Many sailors have reported that spiders have been caught in their ship's sails, even when far from land.

Argiope argentata has five different types of silk, each for a different purpose:Cunningham, A. (2007), Taken for a Spin. Science News vol. 171, pp. 231-233Blackledge, T.A., and Hayashi, C.Y. (2006). Silken toolkits: Biomechanics of silk fibers spun by the orb web spider Argiope argentata. Journal of Experimental Biology 209(July 1), pp. 2452-2461 ( references)

Properties spinning its web.Spider silk is also especially ductile, able to stretch up to 40% of its length without breaking. This gives it a very high toughness (or work to fracture), which "equals that of commercial aramid (aromaticity nylon) filaments, which themselves are benchmarks of modern polymer fiber technology."

The notion that spider silk is stronger than any industrial fiber is a common misconception as whilst some may be stronger, none are tougher (total energy to break). Numerous artificial fibers are similar or stronger, notably aramids like Kevlar and carbon fibre materials (see tensile strength for common comparisons). Nonetheless, there is much interest in duplicating the silk process artificially, since spiders use renewable materials as input and operate at room temperature, low pressures and using water as a solvent. Spider silk can be harvested in large scale quantities if one has proper harvesting equipment. One can also make near-indestructible spider silk threads by weaving the fine threads into thicker and more durable weaves in the same fashion as other industrial threads.

Spider silk is composed of complex protein molecules. This, coupled with the isolation relating from the spider's predatory nature, has made the study and replication of the substance quite challenging. Because of the repetitive nature of the DNA encoding the silk protein, it is difficult to determine its sequencing and to date, silk-producing sequences have only been decoded for fourteen species of spider. In 2005, independent researchers in the University of Wyoming (Tian and Lewis), University of the Pacific (Hu and Vierra), the University of California, Riverside (Garb and Hayashi) and Shinshu University (Zhao and Nakagaki) have uncovered the molecular structure of the gene for the protein that various female spider species use to make their silken egg cases.

Although different species of spider, and different types of silk, have different protein sequences, a general trend in spider silk structure is a sequence of amino acids (usually alternating glycine and alanine, or alanine alone) that Molecular self-assembly into a beta sheet conformation. These "Ala rich" blocks are separated by segments of amino acids with bulky side-groups. The beta sheets stack to form crystals, whereas the other segments form amorphous domains. It is the interplay between the hard crystalline segments, and the elastic semi amorphous regions, that gives spider silk its extraordinary properties.

Synthesis The unspun silk dope is pulled through silk glands, resulting in a transition from stored gel to final solid fiber. Many species of spider have different spinneret for different jobs, such as house and spider web construction, defense, capturing and detaining prey, mobility and in extreme cases even as food. Thus, different specialised silks have evolved with material properties optimised for their intended use.

The gland's visible, or external, part is termed the spinneret. Depending on the species, spiders will have anything from two to eight spinnerets, usually in pairs. The beginning of the gland is rich in thiol and tyrosine groups. After this beginning process, the ampulla acts as a storage sac for the newly created fibers. From there, the spinning duct effectively removes water from the fiber and through fine channels also assists in its formation. Lipid secretions take place just at the end of the distal limb of the duct, and proceeds to the valve. The valve is believed to assist in rejoining broken fibers, acting much in the way of a helical pump.

Various compounds other than protein are used to enhance the fiber's properties. Pyrrolidine has hygroscopic properties and helps to keep the thread moist. It occurs in especially high concentration in glue threads. Potassium hydrogen phosphate releases protons in aqueous solution, resulting in a pH of about 4, making the silk acidic and thus protecting it from fungus and bacteria that would otherwise digest the protein. Potassium nitrate is believed to prevent the protein from denaturating in the acidic milieu.Heimer, S. (1988). Wunderbare Welt der Spinnen. Urania. p.12

The spinneret apparatus of a Araneus diadematus consists of the following glands:

Human use Peasants in the southern Carpathian Mountains used to cut up tubes built by Atypus and cover wounds with the inner lining. It reportedly facilitated healing, and even connected with the skin. This is believed to be due to antiseptic properties of spider silk (which is made of protein)Heimer, S. (1988). Wunderbare Welt der Spinnen. Urania. p.14Some fishermen in the indo-pacific ocean use the web of Nephila to catch small fish. Spider silk, normally that of the golden orb spider, is occasionally harvested and spun into usable textiles. Due to the difficulty of the process, the resulting fabric is invariably extremely expensive, and is generally utilized in fine couture.

The silk of Nephila clavipes has recently been used to help in mammalian neuronal regeneration. Allmeling, C., Jokuszies, A., Reimers, K., Kall, S., Vogt, P.M. (2006): Use of spider silk fibres as an innovative material in a biocompatible artificial nerve conduit. J. Cell. Mol. Med. 10(3):770-777 PDF -

Artificial spider silk Spider silk's properties have made it the target of industrial research efforts. It is not generally considered possible to use spiders themselves to produce industrially useful quantities of spider silk, due to the difficulties of managing large quantities of small spiders (although it was tried with Nephila silk ). Compared to silkworms, spiders are aggressive and will eat one another, making it inadvisable to keep many spiders together in the same space. Other efforts have involved extracting the spider silk gene and using other organisms to produce the required amount of spider silk. In 2000, Nexia, a Canadian biotechnology company, was successful in producing spider silk protein in transgenic goats. These goats carried the gene for spider silk protein, and the milk produced by the goats contained significant quantities of the protein. Attempts to spin the protein into a fiber similar to natural spider silk failed, however. The spider's highly sophisticated spinneret is instrumental inorganizing the silk proteins into strong domains. Specifically, the spinneret creates a gradient of protein concentration, pH, and pressure, which drive the protein solution through liquid crystalline phase transitions, ultimately generating the required silk structure (which is a mixture of crystalline and amorphous biopolymer regions). Replicating these complex conditions in lab environment has proved difficult. Nexia attempted to press the protein solution through small extrusion holes in order to simulate the behavior of the spinneret, but this was insufficient to properly organize the fibers. Ultimately, Nexia was forced to abandon research on artificial spider silk, despite having successfully created the silk protein in genetically modified organisms. Extrusion of protein fibers in an aqueous environment is known as 'wet-spinning'. This process has so far produced silk fibers of diameters ranging from 10-60 μm, compared to diameters of 2.5-4 μm seen in natural spider silk.Scheibel, T. (2004): Spider silks: recombinant synthesis, assembly, spinning, and engineering of synthetic proteins. "Microb Cell Fact" 3:14

See also

References

External links

Spider silk, also known as gossamer, is a fiber spun by spiders.Spider silk is a remarkably strong material. Its tensile strength is comparable to that of high-grade steel — according to Nature (journal), spider dragline silk has a tensile strength of roughly 1.3 Pascal (unit), while one source [http://www.geocities.com/pganio/materials.html lists a tensile strength for one form of steel at 1.65 GPa. However, spider silk is much less dense than steel; its tensile strength to density ratio is roughly five times higher than that of [steel (i.e. it is five times as strong as steel of the same density — as strong as [Aramid filaments, such as [Twaron or [Kevlar.) In fact, a strand of spider silk long enough to circle the earth would weigh less than 16 [ounces (450 [gram).

Usage wraps her prey in silk. Spiders normally use their silk to make structures, either for protection for their offspring, or for predation on other creatures. They can also suspend themselves using their silk, normally for the same reasons.

The trapdoor spider will burrow into the ground and weave a trapdoor-like structure with spindles around so it can tell when prey arrives and take it by surprise.

Many small spiders use silk threads for ballooning (spider). They extrude several threads into the air and let themselves become carried away with upward winds. Although most rides will end a few meters later, it seems to be a common way for spiders to invade islands. Many sailors have reported that spiders have been caught in their ship's sails, even when far from land.

Argiope argentata has five different types of silk, each for a different purpose:Cunningham, A. (2007), Taken for a Spin. Science News vol. 171, pp. 231-233Blackledge, T.A., and Hayashi, C.Y. (2006). Silken toolkits: Biomechanics of silk fibers spun by the orb web spider Argiope argentata. Journal of Experimental Biology 209(July 1), pp. 2452-2461 ( references)

Properties spinning its web.Spider silk is also especially ductile, able to stretch up to 40% of its length without breaking. This gives it a very high toughness (or work to fracture), which "equals that of commercial aramid (aromaticity nylon) filaments, which themselves are benchmarks of modern polymer fiber technology."

The notion that spider silk is stronger than any industrial fiber is a common misconception as whilst some may be stronger, none are tougher (total energy to break). Numerous artificial fibers are similar or stronger, notably aramids like Kevlar and carbon fibre materials (see tensile strength for common comparisons). Nonetheless, there is much interest in duplicating the silk process artificially, since spiders use renewable materials as input and operate at room temperature, low pressures and using water as a solvent. Spider silk can be harvested in large scale quantities if one has proper harvesting equipment. One can also make near-indestructible spider silk threads by weaving the fine threads into thicker and more durable weaves in the same fashion as other industrial threads.

Spider silk is composed of complex protein molecules. This, coupled with the isolation relating from the spider's predatory nature, has made the study and replication of the substance quite challenging. Because of the repetitive nature of the DNA encoding the silk protein, it is difficult to determine its sequencing and to date, silk-producing sequences have only been decoded for fourteen species of spider. In 2005, independent researchers in the University of Wyoming (Tian and Lewis), University of the Pacific (Hu and Vierra), the University of California, Riverside (Garb and Hayashi) and Shinshu University (Zhao and Nakagaki) have uncovered the molecular structure of the gene for the protein that various female spider species use to make their silken egg cases.

Although different species of spider, and different types of silk, have different protein sequences, a general trend in spider silk structure is a sequence of amino acids (usually alternating glycine and alanine, or alanine alone) that Molecular self-assembly into a beta sheet conformation. These "Ala rich" blocks are separated by segments of amino acids with bulky side-groups. The beta sheets stack to form crystals, whereas the other segments form amorphous domains. It is the interplay between the hard crystalline segments, and the elastic semi amorphous regions, that gives spider silk its extraordinary properties.

Synthesis The unspun silk dope is pulled through silk glands, resulting in a transition from stored gel to final solid fiber. Many species of spider have different spinneret for different jobs, such as house and spider web construction, defense, capturing and detaining prey, mobility and in extreme cases even as food. Thus, different specialised silks have evolved with material properties optimised for their intended use.

The gland's visible, or external, part is termed the spinneret. Depending on the species, spiders will have anything from two to eight spinnerets, usually in pairs. The beginning of the gland is rich in thiol and tyrosine groups. After this beginning process, the ampulla acts as a storage sac for the newly created fibers. From there, the spinning duct effectively removes water from the fiber and through fine channels also assists in its formation. Lipid secretions take place just at the end of the distal limb of the duct, and proceeds to the valve. The valve is believed to assist in rejoining broken fibers, acting much in the way of a helical pump.

Various compounds other than protein are used to enhance the fiber's properties. Pyrrolidine has hygroscopic properties and helps to keep the thread moist. It occurs in especially high concentration in glue threads. Potassium hydrogen phosphate releases protons in aqueous solution, resulting in a pH of about 4, making the silk acidic and thus protecting it from fungus and bacteria that would otherwise digest the protein. Potassium nitrate is believed to prevent the protein from denaturating in the acidic milieu.Heimer, S. (1988). Wunderbare Welt der Spinnen. Urania. p.12

The spinneret apparatus of a Araneus diadematus consists of the following glands:

Human use Peasants in the southern Carpathian Mountains used to cut up tubes built by Atypus and cover wounds with the inner lining. It reportedly facilitated healing, and even connected with the skin. This is believed to be due to antiseptic properties of spider silk (which is made of protein)Heimer, S. (1988). Wunderbare Welt der Spinnen. Urania. p.14Some fishermen in the indo-pacific ocean use the web of Nephila to catch small fish. Spider silk, normally that of the golden orb spider, is occasionally harvested and spun into usable textiles. Due to the difficulty of the process, the resulting fabric is invariably extremely expensive, and is generally utilized in fine couture.

The silk of Nephila clavipes has recently been used to help in mammalian neuronal regeneration. Allmeling, C., Jokuszies, A., Reimers, K., Kall, S., Vogt, P.M. (2006): Use of spider silk fibres as an innovative material in a biocompatible artificial nerve conduit. J. Cell. Mol. Med. 10(3):770-777 PDF -

Artificial spider silk Spider silk's properties have made it the target of industrial research efforts. It is not generally considered possible to use spiders themselves to produce industrially useful quantities of spider silk, due to the difficulties of managing large quantities of small spiders (although it was tried with Nephila silk ). Compared to silkworms, spiders are aggressive and will eat one another, making it inadvisable to keep many spiders together in the same space. Other efforts have involved extracting the spider silk gene and using other organisms to produce the required amount of spider silk. In 2000, Nexia, a Canadian biotechnology company, was successful in producing spider silk protein in transgenic goats. These goats carried the gene for spider silk protein, and the milk produced by the goats contained significant quantities of the protein. Attempts to spin the protein into a fiber similar to natural spider silk failed, however. The spider's highly sophisticated spinneret is instrumental inorganizing the silk proteins into strong domains. Specifically, the spinneret creates a gradient of protein concentration, pH, and pressure, which drive the protein solution through liquid crystalline phase transitions, ultimately generating the required silk structure (which is a mixture of crystalline and amorphous biopolymer regions). Replicating these complex conditions in lab environment has proved difficult. Nexia attempted to press the protein solution through small extrusion holes in order to simulate the behavior of the spinneret, but this was insufficient to properly organize the fibers. Ultimately, Nexia was forced to abandon research on artificial spider silk, despite having successfully created the silk protein in genetically modified organisms. Extrusion of protein fibers in an aqueous environment is known as 'wet-spinning'. This process has so far produced silk fibers of diameters ranging from 10-60 μm, compared to diameters of 2.5-4 μm seen in natural spider silk.Scheibel, T. (2004): Spider silks: recombinant synthesis, assembly, spinning, and engineering of synthetic proteins. "Microb Cell Fact" 3:14

See also

References

External links



 

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