Laboratory Products 53 Using Rheology to Investigate Polymer Biodegradability


New data from Malvern Instruments demonstrate how rheological methods can be used to investigate the speed at which biopolymers, such as polylactic acid (PLA), whose low environmental impact is a defining feature, will biodegrade and compost within landfill. The results show how rheological measurements made in the laboratory provide information about the kinetics and thermodynamics of polymer breakdown, helping accelerate the development of products that meet defined biodegradability criteria. The work is presented in a recently recorded webinar entitled ‘Using rheology to assess the biodegradability and compostability of polylactic acid’ and is freely available for download from the Malvern website www.malvern.com/PLA-biodegradability.


The use of PLA is growing as its cost and performance come closer to traditional petroleum-based commodity polymers. Produced from crops, PLA offers the advantage of lower environmental impact and biodegradability is a key element of this. The lifecycle analysis of PLA, in applications such as food packaging, relies on understanding the mechanisms of product degradation, post use, and most importantly, the factors that will accelerate it, or indeed slow it down. Rheological tests are very sensitive to small changes in the microstructure and molecular weight of polymers and are widely used in their characterisation. In the presented study, melt viscosity measurements were successfully applied to track the progressive reduction of molecular weight caused by degradation which proceeds via a process of hydrolytic chain scission. By studying PLA samples held under different conditions it is possible to assess the impact of environmental factors on the rate of polymer breakdown. The resulting information supports the optimisation of polymer properties across the product lifecycle.


MORE INFO. 141


New Integral Autoclave Hoist for More Cost Efficient and Safer Media Loading


The launch of a Loadlite, a new hoist option for integrating into Priorclave top loading autoclaves facilitates easier loading of tall and heavy awkward items into the steriliser, preventing potential for personal back-injury but also enabling the full working height of the vertical sterilising chamber to be utilised. The addition of Loadlite can negate the need to consider purchasing a more expensive, much larger rectangular chamber autoclave, often the only alternative for taller items.


The new Loadlite hoist, available as an option on Priorclave QCS V100 and V150 top loading autoclaves, uses a quick-release clip to easily and securely fix to the handle of a standard wire basket or the company can supply tailor-made collars for fixing to the neck of fermentors for direct loading and unloading. The hoist comprises a vertical column housing a drive rack which directly controls the vertical movement of a 590mm long jib, enabling it to lower and raise directly into the sterilising chambers or swung sideways through a 1200mm arc to lower/pick-up from an adjacent platform such as a trolley, benchtop, etc.


Loadlite becomes an integral part of the Priorclaves and is equipped with a ‘push-button’ handlset on an umbilical cord for controlling the lowering and raising of its jib.


The two top-loading autoclave models for which Loadlite has been designed have 500mm diameter chambers with depths of 500 or 720mm, and loading height of 755mm and 935mm respectively. The addition of the Loadlite options gives laboratories the advantage of operating more cost-efficiently, sterilising heavy awkward or tall items within the confines of the smaller footprint afforded by these smaller top-loading Priorclaves.


MORE INFO. 142


ADVERTORIAL Stuart Introduces New High Capacity Shaking Incubator for Cell Culture Applications


The new SI600 high capacity shaking incubator for cell culture applications with built-in orbital shaker has a capacity of 115 litres - more than double that of the existing SI500 - and can accommodate up to six 2 litre Erlenmeyer flasks. Both of these benchtop systems are equipped with Biocote antimicrobial protection and are ideal for use in cell culture, especially suspension culture applications, with the larger SI600 supporting growing demands for larger scale production.


The SI600 incubator is designed for reliable, convenient operation. Like the SI500 it includes a unique retractable platform for effortless loading and unloading. Under normal use the platform is locked in place but can be drawn forward from the chamber to give easy to access to samples at the back.


Accurate maintenance of a stable and uniform temperature is essential for reliable results over extended periods. Microprocessor control delivers long-term temperature stability, with forced air circulation ensuring uniformity throughout the incubator. Separate control of temperature and shaker speed guards against accidental temperature adjustment, while USB enabled communication allows long term tracking of the incubator temperature.


Ready to roll (and mix)


Stuart roller mixers are ideal for gentle mixing or keeping samples in suspension, providing an effective rocking and rolling action. As one of the first suppliers of tube rollers our experience shows.


Fixed speed analogue or variable speed digital units 6 or 9 roller version


A wide range of stainless steel accessory racks is available with angle-adjustable holders for 1.5ml, 15ml and 50ml sample tubes. These racks magnetically couple to the orbiting platform so require no tools to fix into place. Additionally, the flexible sample platform can accommodate a variety of flasks without the need to add tulip clamps or use tools to secure.


"With life scientists under pressure to scale up production of cell growth, the ability to use larger flasks in the new SI600 enables researchers to increase their chances of success by being able to produce more cells," said Rob Skehens, Marketing Director of Bibby Scientific.


"The SI range is also equipped with BioCote® antimicrobial protection technology. This is a silver ion treatment that helps to reduce levels of bacterial contamination in laboratory equipment, and helps users conform to the principles of good laboratory practice (GLP)."


MORE INFO. 143 MORE INFO. 144 Units can be stacked vertically to save bench space


BioCote antimicrobial protection and 3 year warranty as standard


Find out more!!!


Please scan the QR/Mobile Tag with your smartphone for more information


www.stuart-equipment.com


INTERNATIONAL LABMATE - JANUARY/FEBRUARY 2013


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96