Wednesday, 25 May 2022

Quiet Craft Fairs



“A decade ago or so it was possible to predict sales from a craft fair, but that’s much harder now! It’s an unpredictable market out there right now for crafts and design products! … Even doing a show that was successful in the past might not be so good the next year.
All successful craft exhibitors confirm that they have to work harder to get sales and commissions, do more promotion in advance themselves, and follow up after a craft fair as more people delay their purchase decisions.”
Patricia van den Akker, Crafts Magazine July/August 2014 (page 26)


There are many reasons for quiet fairs. Among them is that the recession and recovery from it has created uncertainty among potential buyers.  House moves, which are big drivers of purchases, are less frequent. On the other hand, there is an increasing awareness of craft and handmade which has led to an increasing number of competing craft fairs.  Online selling such as Etsy creates a new kind of competition for craft fairs.

These and other developments are outside your control.  You can’t affect this. You need to concentrate on the things you can do to make things more successful.  

This is about some of the things you can do.

What Can I Do During the Event?

You will have done your research in choosing this event, which lead you to think it would be successful for you.  During the show you can do some things to help inform you about what to do now.

·        Is there good footfall?  What are the numbers to date compared to previous years? The organisers should be able to tell you how many visitors have come so far. You can make the comparison from your research on previous years.  Don’t panic.

·        Consider the composition of the people who are present.  Are the visitors the right people prepared to buy? What does the visitor profile seem to be?  Are there retail and wholesale buyers present? This is a good opportunity to engage with them for future orders if not present ones.  Networking is important and this is a time and place where you can meet a lot of people and discover reactions to your work, even if they are not buying.  Remember that your fellow stallholders can be part of that supportive network, and even sometimes be future customers.

·        Have you put out enough publicity?  Is there anything you can do now to get people to come before the close?  If you have a quiet time, you can use your social media outlets to tell people about your participation in the event.  Possibly you can offer an incentive for people to come to this show.

·        What does your interaction with the visitors that are at the event tell you? What interest and feedback are you getting? What questions are being asked? Which piece was is most popular? Think about rearranging the placing of your work to better reflect the interests of the visitors.  Can you follow up with the visitors after the show? Are you collecting their contact details?

·        Is your display right for the venue? Can you adjust your display to attract more visitors to the stand? Think about a white board for people to post their reactions to your work.  Which is most popular, for example?  Possibly a special offer is in order. 

·        Are the other exhibitors of a similar price level and quality?  If not, think of ways for your products to appear a better fit for the rest of the event.

·        Are the other stall holders having a quiet time too?  If they are, it may be a general problem with the event.  If you are performing less well than other stall holders, perhaps you have the wrong pricing, or glass products with perceived difficulties for transport.  Lots of packaging is necessary.  Offer a delivery or postal service, if appropriate.

Review the Event

Research – how good was your investigation of the event before you signed up?  
it’s crucial that you research craft fairs before you apply. Choosing the right events to suit your work can be difficult and there are no guarantees of instant return. Don’t be afraid to ask some probing questions of the organisers and past exhibitors.   Patricia van den Akker, Crafts Magazine July/August 2014, p.26.

There are a number of things you should look at to determine if this was the right event for your glass work. 

Organisers

Who organises the event? Look at their track record for this and any other events they organise.  There are sites for rating events that you can use such as Folksy’s.  You can look at Trip Advisor show reviews  for the visitor reactions.

Exhibitors

Who the other exhibitors are, or have been, is important in judging your fit within the group of exhibitors.  This information should be available from the organisers.  Are these your peers in price and quality?  Think about how you will both fit with them and stand out from them.

A good craft fair curator should make sure there’s a wide mix of things and not too many of the same.  David Andrews, And at What Cost

Visitor numbers and average sales

The organisers should be able to tell you of the number of visitors to previous events and at least the average sales of the event.

Visitor profile

Does the proposed event seem to be oriented to buyers?  If the craft fair is in support of a main event, you need to determine if your glass work will fit the apparent interests of visitors to the main event.  You may be able to make items that will interest them.  If the craft fair is the main event, you have a greater chance of the visitors being buyers.

The publicity may be oriented toward individuals, or to buyers for businesses and wholesalers.  These will each need different approaches.  The organiser should be able to tell you about the composition of the visitors for previous event.

Publicity for the event

Look at the publicity issued for previous events.  The organisers often give you this information.  This will provide an idea of what they produced and maybe how it was distributed.  Look at what local, and if appropriate, regional and national, press was obtained.  Did they get into lifestyle publications? What business and trade press was received?

Visit the event

If at all possible, visit the event.  This will give you a first-hand feel of the style of the event.  You will be able to see the range of exhibitors, the various styles of stands.  This will help you determine if this is an event you would fit into.  It also will  give you ideas to help design your exhibit. 

You can engage with exhibitors that appear to have a business of a similar size to yours to get the benefit of their experiences. You must be careful about this.  Be honest.  State that you are a potential exhibitor and ask if they have the time to give their experience about this event.  Approach them only when they are quiet.  Be aware of the need to avoid blocking other visitors from the stand.  Do not engage in long conversations.

If you can’t visit, look at the social media of the organisers and any exhibitors you know attended.  This will give some feel of the previous event. 

Location

This is about where the event is being held in relation to your location.  Do you need to travel and stay somewhere to attend, or is it near enough to avoid overnights?

It is also about where the event is located.  Venues range from dedicated events arenas to school gyms.  How easy is it to find? Is it signposted well? What are the parking facilities?  Look at the venue as though you were a visitor and decide on the suitability of the place.

Consider the timing

Craft fairs are held throughout the year, but those in the months leading up to Christmas most often get greater footfall and have a higher proportion of buyers.  Summer shows are influenced by the weather – a sunny day can take everyone to the beach or lakeside, but a stormy, rainy day can keep everyone inside.

Try to make your products relevant to the existing season or the coming one.  Think about opportunities people want for securing gifts relating to celebrations or awareness days.  Trade shows are often working 6 to 9 months in advance so the buyers can get the products into stock for the relevant season.

Promotion

This is not about what the organisers do, although that is important.  It is about what you do to generate interest.  There are going to be a lot of competing products.  You need to generate interest in people coming to your stand. 

My bugbear is exhibitors who expect footfall and sales and rely too much on the organisers. YOU need to do marketing & social media to get sales. – Patricia van den Akken, The Design Trust on Twitter.

You should be prepared to do a lot of social media work in the months and weeks leading up to the event.  You need to be telling people about your participation and preparation for the show.  You should make up a press release about the show and your participation in it.  Even if this is not taken up by the press, the material in it can be used for all the other marketing  you do.

You need to ensure that you provide the organisers with text and excellent photographs well before the deadline they impose.  If you have good images of your glass work and send them in plenty of time, you have a greater chance of being featured in one way or another.

After the Show

You need to consider what lessons can be taken from a quiet show.

Display
Review the layout of your stand.  Does it do justice to the quality of your glass work?  Think about what you can do to make the glass more eye catching – lighting, space for each item to breathe, clear pricing, arrangement, etc.  Make it clear what you do, what you make and why.

Product range

“When planning which products to sell at a craft fair, think 1) affordable, 2) achievable, 3) aspirational, and try to bring a range of products so you have all three covered.”  Folksy

This is applicable to all shows, perhaps with the exception of trade shows, where you need to concentrate on glass work that you can produce in quantity.  If you can produce a variety of glass with a group of price points, you will make it easier for buyers to choose.  Of course, you will need more items in group one, with a moderate amount of group two and only one or two of group three.

After a quiet fair you need to reflect on whether the glass range you brought was a fit for the event.  Were they relevant to location, suitable for the season, relevant to the event, suitable for a range of ages, etc. You need bring only the relevant products, not your full range of glass work.

Engagement

You need to review your performance at the show too.  Look at how you interacted with the people who did stop by.  You need to be sure you maintain a friendly appearance throughout.  Did you enjoy your conversations with visitors?  If not, you need to work on picking up on their cues.  You need to get them talking about themselves and their interests to be able to direct them to the appropriate glass.  Are you approachable?  Being at the front of your stand is important to drawing people in.  Showing your enthusiasm for doing your glass is important, because people like a story about the maker and her glass.  This helps engage people with your work and may lead to purchases.

Transport

Glass is heavy, and perceived to be fragile.  You need to find ways to overcome these resistances to buying.  Some things you can do are:
  • excellent packaging (bring lots);
  • a pick-up service (after they have paid and given their contact details) before they leave the event;
  • after show delivery by post or courier. 
There will be others that you can think of too.  Signpost these services, so people know while they consider their purchase.

Payment

It is essential that you are able to take card payments.  You can use PayPal.  There are a number of companies that either have short term hire of terminals, or do not have monthly charges (although their percentage take is a bit higher).  Without electronic payment facilities, you will lose many sales.

Reflect on the Benefits of Attending Events

Feedback

You get direct feedback on your work, its pricing, and how it fits with people’s lifestyle.  You can learn of misunderstandings about your glass and so correct or anticipate them in the future.  Conversations at shows can be vital in guiding the direction of your work.

Networking 

Communicating with other stall holders makes a community of interest and support.  Also, potential customers can be discovered at shows and some of them may be the fellow stallholders. Making good relations with them has the potential to get write-ups about you from them in their discussion of the fair on social media, just as you may and should write about them even though they don’t do glass.

Meeting people that can promote your work

There is a great variety of people who are not buyers but are looking for things and people to write about.  This is great publicity.  The craft press attends shows looking for items of interest to their readers. Bloggers increasingly are writing about people they discover at events. Stylists, interior designers and influencers are also milling about.  You will not always recognise them from their badges, but treating everyone with enthusiasm for your glass work will include them.  They may give you feedback at the show or be available afterwards to contact and learn of their views.

Stockists

Shows are good places to meet stockists, who may be retailers, shops, galleries, wholesalers and others who want to stock your glass.  Take details and follow up all of these contacts.  You should be prepared for these people by having price lists and  professionally produced publicity material under the counter to give to them.  Business cards are essential.  If you offer one, you will get theirs in return.

Future sales 
It is not only stockists that you need to keep a list of contacts.  Get the details of all the interested people and contact them after the show and in the future when appropriate.

I do believe that craft fairs and events are still one of the best marketing tools for creative businesses. They help you to build your profile, to reach many potential clients in a short period of time who can get to know you a lot better, and events can really boost your confidence too.

But … you do need to … promote yourself! Even if your contacts are unable to attend the event it’s crucial that you let them know through a series of emails, blog posts and social media. Events are one of the best ways to stay in touch with your potential clients!

An event invite can be a great tool to drive more traffic to your website and get online sales instead.

Selling events aren’t there just to get sales but are also a way to stay in touch with potential clients, to increase your profile, and to get new contact details for your database. Start a database and stay in touch. And by following up you can often turn a quiet craft fair into a pretty successful one!
Patricia van den Akker, Crafts Magazine July/August 2014 (page 26)



Take advantage of quiet events to reflect on what you can do during the show and after the show to make for better outcomes in the future.  Reflect on your research of the event.  Consider location, timing, relation to a main event or awareness week or month.  Look at your promotional effort leading up to the show.  Consider how to improve your marketing.  Remember that even a quiet show can provide great contacts and that follow-up with the people you have met can garner purchases.  Not everything is about the immediate monetary returns.

Tuesday, 24 May 2022

Stained Glass Project Sheet

Why is a project record sheet useful?

 

A record of a project helps to set down the client and maker agreements, estimate quantities, determine prices, review past practices for successes and record possible changes for the future.  Even if you do not have clients, comparing the record sheets over a period can give you information on how quickly you work, the amount of glass you use in relation to size and complexity, information for costing, etc. It can give you confidence in stating - and sticking to - your prices.

 

What should be included? 

Desirable elements include the following.  You may have others to add according to your individual practices.   

Initial project information

  • ·        Project description - including dated sketch or photo or reference to cartoon
  • ·        Intended location – autonomous, primary glazing, encapsulated, attached, etc.
  • ·        Dimensions for both two- and three-dimensional projects.
  • ·        Delivery date. This may be an estimated or firm date.
  • ·        Price or estimate – indicate which. 

Materials

·        Number of pieces. Approximate the number, if a numbered cartoon is not available. You can add the actual number later.

·        Glass type and codes that you will (or have) used, in case additional glass is required.

·        Amount and cost of glass used during completion. This is not simply the amount used, but also the amount you would require to replace the glass stock.   

·        Joining materials: came, copper foil, lead light cement, patina, adhesives, wire, mountings, etc.  These should once again include what needs to be purchased with their costs, rather than just the amount used. The whole roll of copper foil, the whole tub of lead light cement, etc., need to be accounted for on the form to give an accurate idea of costs.

·        Solder manufacturer, type, composition, and quantity purchased, and costs, rather than what is used. 

Process methods

Cleaning, Polishing, etc. descriptions. 

Time

The time used to complete the project should be noted as you go along.  It can be divided into various process – such as cutting, fitting, foiling, soldering, cleaning – or as a simple cumulative amount of time on the whole project.

Description of project results

A critique of the project including what might be done differently, the successes, the discoveries, should be written up at the end of the project. 

 

What does all this record keeping provide me?

Recording this kind of information provides a record of how various projects went, how you met any difficulties, what the successes were.  This is useful to look back on when similar projects arise. 

This information is invaluable in assessing materials costs, and time required for various styles and complexity of projects are requested.  It enables a quick and assured way of estimating the costs of a project when a commission is requested.  It gives you assurance about your pricing and valuation of projects you have completed for craft fairs or friends. You don’t have to be apologetic about the price of items, because you know the costs. 

A possible form might look like this:

 

 

Project information 

Name of project:

Date:                           Clients:  

                           Contact details:

 

Due date:

Project title and description (photo?)

 

 

 

 

Dimensions  2D                                        3D

       Opening:                                   height:

       Glazing:                                     width:

       Sight:                                        depth:

 

Number of pieces:

 

Materials required

Glass descriptions,         codes              quantities       costs

 

 

 

 

 

 

Copper foil - maker:       size               rolls               costs

 

 

Came – maker        dimensions     lengths                  costs

 

 

Lead light cement – type, recipe, amount,                   costs

 

Solder – Maker        composition           length/rolls     costs

 

Adhesives – maker     amount                                  costs

 

Miscellaneous materials – description     quantity         costs 

 

 

Summary of Costs of Materials                      _______

Processes

The starting and finishing time, including any attention to equipment should be recorded for each working session.  The actual hours and minutes can be added up later.  You can simply record the times for each project regardless of process, e.g.:

__:__  to __:__;  __:__  to __:__;  __:__  to __:__;

__:__  to __:__;  __:__  to __:__;  __:__  to __:__;

__:__  to __:__;  __:__  to __:__;  __:__  to __:__;

 

Or you can record by process, e.g.

Cutting and fitting glass:   times , e.g.

__:__  to __:__;  __:__  to __:__;  __:__  to __:__; etc. 

 

Leading - times

__:__  to __:__;  __:__  to __:__;  __:__  to __:__; etc. 

 

Foiling -times

__:__  to __:__;  __:__  to __:__;  __:__  to __:__; etc. 

 

Finishing – times

__:__  to __:__;  __:__  to __:__;  __:__  to __:__; etc.  

 

Summary of time:                                   ___:__ 

 

You will, of course, develop your own form of recording your project materials, costs and time used for the project.  But it is important to keep some record of what amount of effort and cost has gone into each project.  Over time, things seem easier and less costly than they actually did.  A record of the project reminds you of the actual matters.

Sunday, 22 May 2022

Measuring Glass Viscosity

 

Measuring Glass Viscosity

Posted  on 


Glowing glass

What is glass viscosity?

Viscosity is a measure of a liquid’s fluidity, and is measured through a substance’s resistance to motion under an applied force. It is also known as the thickness of a fluid. It is calculated by dividing shear stress (the force per unit area required to move one layer of fluid in relation to another) by shear rate (the measure of the change in speed at which intermediate layers move with respect to one another). The result is usually expressed in poise (P), the equivalent of 0.1 Pa∙s (pascal second). 

Glass viscosity varies inversely with temperature. As it is heated, viscosity decreases and it flows more easily. This is because the thermal energy produced causes the structural molecules to move faster and break the bonds between those molecules. As the temperature decreases, viscosity increases, causing the structural bonds to re-form.

The relationship between temperature and viscosity is linked directly to the chemical composition of a glass. Manufacturers need techniques to measure and model this relationship for a range of glass compositions and temperatures. The viscosities of most commercial glasses like soda lime and borosilicate are measured between 800°C and 1400°C.

Why is glass viscosity important?

The visocisity of a glass significantly affects other physical properties, such as softening, melting and crystallization characteristics, as well as the temperature and pressure ranges within which the glass can be worked. Knowing the relationship between temperature and viscosity is key to determining the correct melting and heat treatment regimes in glass production and processing.

Manufacturers monitor temperature and viscosity throughout the manufacturing process in order to know how the glass will behave. For example, viscosity can directly affect refractory corrosion and the ability to homogenize a melt. It is important during the fining process to ensure the batch chemicals are properly melted and air bubbles are forced out. Additionally, a glass’s viscocity gives manuacturerses the ability to predict how the glass will perform in the glass forming process such as casting monolithic parts, spheroidization, or fiber generation.

Measuring viscosity

Most viscometers work by comparing a stationary object and a flowing fluid, or a moving object and a stationary fluid. They measure the drag resistance during this movement. There are a range of viscometers available.

Rotation viscometers are commonly used to measure the viscosity in the range of 1 to 104 Pa·s. They employ a platinum alloy spindle immersed in a crucible of molten glass. Spindle torque is measured and used to calculate viscosity. The crucible can either be stationary and the spindle rotates, or the crucible rotates and the spindle is stationary. Generally, data points are taken as a function of temperature to describe the viscosity curve for the glass.

Falling sphere viscometers can be used to measure the viscosity in the range of 1 to 106 Pa·s. They measure the time taken for a falling sphere of known density and radius to move between two points. This method employs principles from Stokes’s Law, which takes into account the drag force on a falling sphere.

Parallel plate viscometers measure the rate of change in thickness of a cylindrical specimen between parallel plates moving perpendicular to their common central axis. This method is often used to measure the viscosity in the range of 105 to 108 Pa·s.

Fiber elongation viscometers measure the elongation rate of a fiber of known dimensions under a known load. This method can be used for viscosities ranging from 105 to 1012 Pa·s and it is widely used to determine the Littleton softening and annealing reference points.

Transformation range viscosities (108 to 1013 Pa·s) are often measured by the beam-bending method. Beam-bending is a method in which the rate of viscous bending of a simply loaded glass beam is measured over an extend period of time.

Glass analytical services from Mo-Sci

Mo-Sci is able to undertake several types of chemical and physical characterization on glass samples, including high-temperature viscosity measurements. Our fully equipped glass laboratories are set up to conduct analytical tests for manufacturing, quality control, failure analysis, and R&D. We also employ a large collection of standards against which most glass samples can be compared and measured.

References

  1. The Physics Hyper-Textbook, Viscosity  https://physics.info/viscosity/
  2. The Glass Packaging Institute, Viscosity https://www.glass-ts.com/services/temperature-viscosity
  3. Glassglobal Consulting, Glass properties https://www.glassglobal.com/consulting/reports/glass/properties.asp:
  4. Bright Hub Engineering, Types of Viscosity Measurement Devices https://www.brighthubengineering.com/fluid-mechanics-hydraulics/83996-viscosity-measurement-equipment/
  5. ASTM C965 – 96(2017), Standard Practice for Measuring Viscosity of Glass Above the Softening Point https://www.astm.org/Standards/C965.htm
  6. Designation: C1351M − 96 (Reapproved 2012), Standard Test Method for Measurement of Viscosity of Glass Between 104 Pa·s and 108 Pa·s http://materialstandard.com/wp-content/uploads/2019/09/C1351M-96-Reapproved-2012.pdf 
  7. ASTM C1350M – 96(2019), Standard Test Method for Measurement of Viscosity of Glass Between Softening Point and Annealing Range (Approximately 108 Pa·s to Approximately 1013 Pa·s) by Beam Bending, https://www.astm.org/Standards/C1350M.htm
  8. Mo-Sci Corporation, Analytical Services https://mo-sci.com/research/analytical-services/

Wednesday, 18 May 2022

Large Uprisings on Slumps



Help!  Looks like my shallow bowl wanted a boob.  [16” diameter pot melt slumped into shallow 20” mould, 4” above floor, fired at 175°F to 1100°F for 20 minutes,  and 75°F to 1250°F for 15 minutes]

What happened?

Sometimes a slump results in an uprising at the bottom of the slump. In this case, and many others, we know the vent at the bottom of the mould was open and the piece was supported above the shelf.  This indicates that everything should be set up for a good result.  Still, this uprising occurred.  It is not a bubble, as the glass is apparently evenly thick throughout the “boob”. 

The usual, and mostly unexpected, cause is too long or too hot a slump.  The firing, if allowed to continue, would result in a larger uprising and eventually a thickening of the piece at the bottom of the mould associated with a related reduction in the dimensions of the final piece.

What has happened is that the glass has become soft enough for it to slip down the sides of the mould. But it has not been hot enough for long enough to allow the glass to thicken.  The glass at the bottom is pushed up to compensate for the slightly hotter glass on the sides of the mould sliding down on the glass at the bottom.

In this case there is a moderate (97°C) rise from a soak of 20 minutes at 593°C to 676°C, soaking for 15 minutes.  This is a lot of heat work at a relatively high temperature for a shallow mould. 

What to do in the future?

Rate of Advance

Consider what you are trying to achieve at each stage of the scheduling of the process.  In this slumping there really is no need to soak at 593°C. It is a nowhere temperature.  The glass is no longer brittle.  It is at the lower end of the temperature range where the glass is softening anyway.  A simple, steady rise in temperature, as at the beginning, of at or below 100°C will be sufficient to bring the whole substance of the glass to the slumping temperature. If the piece is really thick, consider an even slower but steady rate of advance without any soaks.

Soak Temperature

Also, if the slump can be achieved in 15 minutes, it is too hot.  If the slump is complete in such a short time, it will be marked much more than needed by contact with the mould. 

The cooler the glass at the conclusion of the slump,  the less marking there will be.  Yes, the soak time needed to complete the slump will be longer, but the bottom of the glass will be cooler than a hot fast slump.  You should always be trying to achieve the effect you need at the lowest practical temperature.  The slow rate of advance will assist in completing the slump at a lower temperature, as the amount of heat work put into the piece will be greater.

Observe the progress of the firing

Observation is necessary when doing something different.  Some argue that it is necessary in every slump.  I admit that I do not always observe every slump, but this case again illustrates the need to observe each slump. 
By observing at 10- or 15-minute intervals, you will see when the slump is complete.  You may feel you do not have the time to wait for an hour or so for the slump to be complete, or that it does not fit with your activities.  The answer is to arrange the kiln’s schedule so that when the critical part of the process is reached it will fit with a space in your other activities. https://glasstips.blogspot.com/2016/12/diurnal-firing-practices.html

Can this piece be fixed?


You could put the piece on a shelf and take it to a high temperature slump with a significant soak to flatten it.  You will need to observe when the uprising is flat again, and then proceed to anneal.  However, the pattern placed in or on the glass will be distorted to some extent.  The uprising will flatten with a thicker rim around the base of the rise in the glass.  This may be visible. 

My view of these things is to learn as much as you can about causes and prevention and move on.  You advance your practice more quickly by understanding what went wrong and why than by trying (unsatisfactorily) to rectify a failed piece.  Often you can cut the glass up and use the pieces in other projects.

Further information is available in the ebook: Low Temperature Kiln Forming.

Uprisings at the bottom of slumps are often the result of too much heat work (rate, temperature and time).  Slow rates if advance to low temperatures with long soaks backed by observation prevent the occurrence of these bubble-like uprisings.

Sunday, 15 May 2022

Using Silver-Releasing Glass to Reduce Bioburden

 

Using Silver-Releasing Glass to Reduce Bioburden

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Silver has been used for wound management for over 200 years, and its anti-microbial properties have been known since the 19th century.1 Although its direct use in the treatment of wounds fell out of favor when antibiotics were introduced, it continued to see applications in treatment for burns and other conditions on the surface of the body.

Recently, interest in silver has been renewed following research involving the use of silver with bioactive glasses that are implanted directly into the body. The unique properties of the glass and silver material allow it to be deployed in areas where antibiotics cannot reach; while the glass containment also allows more control over the concentration of silver ion released in specific areas.

Challenges with antibiotic resistance

A serious problem in all countries around the world is the rise of antibiotic-resistant bacteria that can cause issues for patients before, during, and after surgery. This includes strains such as methicillin-resistant Staphylococcus aureus (MRSA), that form biofilms on hospital equipment and surgical implants, increasing the bioburden on these surfaces.2

This is a particular problem for surgical implants: medical implant failure is commonly caused by infections resulting from bacteria living on implant surfaces. Due to the position of the implants and nature of the bacteria, these biofilms can be difficult to eliminate using antibiotics alone and treatment may require surgical removal.

How does silver impact bacteria?

One method of inhibiting the growth of antibiotic-resistant strains of bacteria on surgical implants is to coat them with silver-releasing glass. These glasses have been shown to be effective in reducing bacterial adhesion at the surface of implants, and the addition of silver further inhibits the development of biofilms on implant surfaces.3

The exact mechanism of how silver impacts bacteria is debated among scientists, but it’s generally accepted that the antibacterial action involves the release of Ag+ ions that interact to disrupt pathogens, compromising their ability to successfully replicate.4,5

Producing silver releasing glass

Conventional melt-quenching methods have proved successful in producing silver-doped glasses, however, difficulties in producing controlled and reproducible levels of silver below the allowed tolerance in humans prevent these techniques from being widely adopted. Other methods such as a sol-gel route have been explored – this enables much finer control over the introduction of the silver into the material structure.6

The future of research into these materials involves ensuring that there is sufficient silver to provide effective protection, while preventing the silver from leaching too quickly into the body and causing separate issues.

One promising method of activation is the use of phosphate-based glasses, which are soluble materials that allow for the controlled delivery of the silver ions.5 By incorporating the ions into the structure of the glass the two become a single phase and the rate of release of the silver is determined by the speed at which the glass degrades.

Phosphate-based glasses have already proven to be effective in delivering silver ions to help control urinary tract infections in patients with long-term indwelling catheters, as well as being used in wound dressings to prevent infections.5

The number of people requiring implant surgery is set to increase as life expectancy of the world’s population is expected to increase. This makes research and development of silver releasing glasses all the more important, and the procurement of high-quality research materials is vital.

Mo-Sci has extensive experience in the manufacture of biomedical glasses for healthcare, with a number of options for direct purchase. These biomedical glasses are available in sizes ranging from a few microns up to millimeter-sized structures depending on the form of the glass, and can be made into a range of shapes including microspheres, porous structures, and powders.

Custom solutions are also produced with Mo-Sci’s expert team of engineers and technicians to research, develop and produce glass which is custom-made to fit a wide range of applications. Contact us for more information.

References

  1. Clement, J. L. & Jarrett, P. S. Antibacterial Silver. Met. Based. Drugs 1, 467–482 (2007). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2364932/
  2. Valappil, S. P., Knowles, J. C. & Wilson, M. Effect of Silver-Doped Phosphate-Based Glasses on Bacterial Biofilm Growth. 74, 5228–5230 (2008). https://aem.asm.org/content/74/16/5228
  3. Cabal, B. et al. A new biocompatible and antibacterial phosphate free glass-ceramic for medical applications. Sci. Rep. 4, 1–9 (2014). https://www.nature.com/articles/srep05440
  4. Agostino, A. D. et al. Seed mediated growth of silver nanoplates on glass: exploiting the bimodal antibacterial effect by near IR photo-thermal action and Ag + release †. 70414–70423 (2016). https://pubs.rsc.org/en/content/articlehtml/2016/ra/c6ra11608f
  5. Valappil, S. P. et al. Effect of Silver Content on the Structure and Antibacterial Activity of Silver-Doped Phosphate-Based Glasses. 51, 4453–4461 (2007). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2168012/
  6. Rahaman, M. N. Bioactive ceramics and glasses for tissue engineering. Tissue Engineering Using Ceramics and Polymers: Second Edition (2014). doi:10.1533/9780857097163.1.67 https://www.sciencedirect.com/science/article/pii/B978085709712550003X
  7. Mo-Sci Glass Products https://mo-sci.com/en/products