News. Pharma & Biotech. Prevent Samples from Binding to Pipette Tips. Analytical solutions in the laboratory

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1 Pharma & Biotech Analytical solutions in the laboratory 10 News Prevent Samples from Binding to Pipette Tips Sensitive experiments, like those dealing with DNA or proteins, might lead to incorrect results if the sample adheres to the pipette tip. New, low-retention (LR) tips minimize sample interaction with the plastic tips. LR tips are now used in the early detection of diabetic retinopathy to gain the extra accuracy required with such delicate tests. Eighty percent of patients suffering from diabetes for a period of at least 10 years are affected by diabetic retinopathy, a secondary eye disorder. This retina damage can even lead to blindness. However, vigilant screening and timely treatment can reduce the number of new cases by 90 %. Furthermore, diagnosis in the early form of diabetic retinopathy, classified as non-proliferative diabetic neuropathy (NPDR) consisting of mild or no ophthalmological symptoms, could reduce this number even further. The answer lies in the proteins In a paper published in the Journal of Proteome Research, Kim et al explored the use of a highly sensitive, liquid chromatography mass spectrometry detection method called multiple reaction monitoring (MRM) to quantify protein biomarkers for patients at risk of developing NPDR. The researchers collected plasma samples from non-suffering patients and NPDR patients according to the three stages of NPDR: Mild, moderate and severe. The authors found 28 different proteins that had different concentrations in the plasma of non-suffering patients, mild NPDR patients and moderate NPDR patients. After analyzing these 28 potential biomarker proteins, Kim et al developed two 4-biomarker panels that exhibited great discriminatory power for mild NPDR, mild and moderate NPDR and non-suffering patients. Each biomarker protein matters The experiments here used highly sensitive mass spectroscopy for the peptide

2 Low Retention Tips detection so it was essential that all the molecules of interest remained intact throughout sample preparation processes. Since many plastic consumables, such as pipette tips, can retain some of the molecules of interest on the plastic, the quantitative end result can be affected. It is critical to use plastic components that have low retention properties in order to generate accurate and quantitative data. The results of the paper depended on using low-retention plastic components so the research team used Rainin Low-Retention pipette tips to combat this common problem. A solution for sticky liquids METTLER TOLEDO has recently launched a new generation of Rainin Low Retention tips. These are commonly used in laboratories when it comes to the pipetting of sticky and viscous liquids, such as buffers containing glycerol, proteins or DNA, etc. The special surface of Rainin LR tips eliminates adhesion and prevents samples from interacting with the polypropylene surface of the tip. This optimizes fluid movement within the tip and helps to limit the residual volume of fluid left in the tip after dispensing to improve pipetting accuracy and reproducibility. Prevent liquid retention The highly repellent tip surface guarantees uniform fluid movement across the internal tip surface to ensure complete sample aspiration and discharge regardless of fluid composition. In the picture, low-retention tips vs. normal tips. Text: Rishi Porecha Rainin Application Specialist Watch the Video Electronic Pipette E4 XLS Publisher Mettler-Toledo AG Laboratory Division Im Langacher CH-8606 Greifensee, Switzerland Production LAB Division Marketing Global MarCom Switzerland Subject to technical changes. Mettler-Toledo AG 02/15 Printed in Switzerland. 2 METTLER TOLEDO Pharma & Biotech News 10

3 Particle Vision & Measurement for Elusive Crystallization Mechanisms Crystallization process Particle growth, nucleation or breakage in a crystallization process cannot be quantified offline. Researchers are turning to in situ visioning in order to gain process understanding and shorten development times. For more than 700 years, microscopy has helped humans visualize tiny structures. But when it comes to crystallization processes, traditional analytical techniques, such as offline light microscopy are limited since temperature and pressure changes that occur during sampling can disrupt delicate structures. What s more, without a continual process view, key mechanisms that influence growth, such as secondary nucleation, seed aggregation and phase separation (oiling out) may be missed entirely. This can affect yield, purity, polymorphic form and par- ticle size. This then negatively impacts downstream operations, such as filtration, drying and formulation. Capturing transient mechanisms Probe-based in situ microscopy, on the other hand, provides thousands of highresolution process images that help researchers gain immediate understanding throughout a crystallization process. This avoids the wasted time and effort of offline analysis. Not only is key information about particle size, shape and structure conveyed, but dynamic mechanisms, such as growth, nucleation, agglomeration, breakage and shape change, can also be quantified with little ambiguity. With such accurate and detailed information to hand, critical parameters, such as feed and cooling rate, can be adjusted in real-time and lead to faster development, higher yields, enhanced purity and easier downstream processing. Text: Des O Grady Particle System Characterization Market Manager Crystallization & In Situ Microscopy This White Paper presents the benefits of in situ microscopy applied to crystallization processes. Reputed chemical companies and teaching institutions explain how they benefit from this method. Download the white paper METTLER TOLEDO Pharma & Biotech News 10 3

4 Differential Weighing Understanding Uncertainty for Accurate Differential Weighing Determining a weight value by differential weighing can result in increased measurement uncertainty. This can significantly affect the accuracy of results, particularly when weighing small samples. Gaining a better understanding of measurement uncertainty ensures optimum balance selection for a specific application in order to meet process accuracy requirements. Differential weighing, including backweighing, involves weighing a sample before and after a process, e.g. drying and materials dispensing in order to determine the difference in weight. The process is common in pharmaceutical laboratories, but requires an understanding of both the method and application requirements in order to select the right balance for the job. A sensitive situation A pharmaceutical company was seeking to determine the efficacy of a scar-reducing cream. 5 mg of the cream was being weighed out onto a plastic applicator and then wiped onto an artificial membrane for analysis. The weight of the applicator before and after dispensing the cream determined the actual amount of cream dosed. The company turned to METTLER TOLEDO to clarify whether the method ensured accurate results. Process challenges The laboratory needed to weigh 5 mg of cream onto a 60mm long applicator stick in accordance with USP41. The process had to be performed quickly and up to 30 times per day. METTLER TOLEDO s Good Weighing Practice (GWP ) established that the method was not adequately satisfying process requirements and our experts recommended a new microbalance for better accuracy. More than minimum weight METTLER TOLEDO s XP6, XPE26 and XPE26DR microbalances were considered. However, the weighing chamber of the XP6 was simply too small to accommodate the applicator stick, leaving the XPE26 and XPE26DR microbalances which both have a larger weighing chamber and expected USP minimum weight values of 1.4 mg and 2.4 mg respectively. Theoretical minimum weight values are determined under ideal weighing conditions. In a laboratory, where conditions are not always perfect, METTLER TOLEDO recommends applying a safety factor to the expected USP minimum weight values. The usual recommendation is a safety factor of 2, resulting in a 2-fold increase in the established USP minimum weight to be used as the smallest net weight. For the XPE26 and XPE26DR, the minimum weights become 2.4 mg and 4.8 mg respectively. These are lower than the target sample weight of 5 mg, so both balances would be suitable. However, total differential weighing measurement uncertainty is defined as: uu! = uu!! + uu!! Where u_t is the total measurement uu! uncertainty; u_a and u_b are the measurement uncertainties associated with the two weight measurements (the applicator with and 2uu without! uu! = uu!! + uu!!! = the 2 cream). uu = If both uncertainties are approximately uu! equal uu to each other (i.e. u_a u_b), then the equation is simplified: mplified: uu! = 2uu!! = 2 uu = 1.4uu So, in the case of differential weighing, the measurement uncertainty is 1.4 times higher than that of a single measure- 4 METTLER TOLEDO Pharma & Biotech News 10

5 XPE26 micro balance ment. With this increase in measurement uncertainty, it is recommended to increase the safety factor, e.g. to 3, resulting in the minimum weight values of the XPE26 and XPE26DR becoming 4.2 mg and 7.2 mg respectively. As 4.2 mg is less than the 5 mg sample weight, the XPE26 is the clear choice to ensure results meet GWP, USP and, of course, the company s accuracy requirements. Text: Simon Taylor, Analytical Balances Product Manager When Quality Really Matters to Pharmaceutical Labs Read about how Good Measuring Practices guidelines help you ensure operators and consumers safety and meet stringent regulations. Download the White Paper } METTLER TOLEDO Pharma & Biotech News 10 5

6 Hot-stage Microscopy Morphological Changes in Drug Compounds Under the Microscope Heated crystalline pharmaceutical compounds undergo morphological changes that can be observed under a microscope. Changes in melting points and ranges or crystallization can be visualized using hot-stage microscopy. This is important for research and QC purposes in order to influence drug stability or effectiveness. Hot-stage microscopy (HSM) is the combination of microscopy and thermal analysis. It enables the study and physical characterization of materials as a function of temperature and time. The yielded insights are of special use in pharmaceutical companies to either formulate more stable and effective drugs or to test the pharmaceutical compounds according to industry QC standards. Polymorphic changes Polymorphism is when a substance exists in several different crystal structures that also look different. This affects physicochemical properties, stability and performance. HSM is an ideal tool for identifying different polymorphs through the visualization of diverse crystal appearances and by determining their unique melting points. Suberic acid exhibits crystallization and several solid-solid transitions as soon as it is heated from the glassy state. Figure 1 shows the sample at 40 C where it exists in form V. If the substance is heated slowly to 135 C, it undergoes a transition to form I (Figure 2). Under polarized light, it is easily possible to differentiate between the various forms. Isothermal crystallization studies The crystallization behavior can also be studied as a function of cooling rate and temperature. Chlorpropamide, a drug used to treat diabetes mellitus, crystallizes readily from the melt. The sample can be cooled at a constant rate or held isothermally. Crystals of different morphology form depending on the cooling profile. Figure 3 shows different crystalline forms of chlorpropamide that were obtained through isothermal crystallization at 100, 90 and 80 C. Both the size and the number of crystals are influenced by temperature. At high temperatures, nucleation rate is low and crystal growth rate high forming a small number of large crystals (left). The lower the temperature, the higher the nucleation rate becomes and the lower HS 1 control unit HS82 & HS84 microscope Hot Stage Controller the crystal growth rate. This can be seen from the increasing number of small crystals at lower temperatures (Figure 3: Middle and left). Solvate studies A solvate of a crystalline solid is an inclusion compound containing both the molecular solid and one or more types of solvent entrapped in isolated sites, layers or channels within the crystal structure. A special form is the hydrate where the included solvent is water. There are two ways to investigate solvates/hydrate using hot stage microscopy. In a dry preparation (Figure 4) the sample is placed between a microscope slide and a cover glass and then heated. Occurring desolvation (where the solvent is expelled from a solid) is often associated 6 METTLER TOLEDO Pharma & Biotech News 10

7 Figure 1 Figure 2 Figure 3a Figure 3b Figure 3c Figure 4a Figure 4b Figure 4c Figure 5 with internal changes in crystal structure and makes them look darker due to the decreased light transmittance of the new structure. In a wet preparation, (Figure 5) the sample is placed in immersion oil and heated. Gas evolution can be observed as bubbles at the interface solid/oil when the crystals desolvate. Hot stage: The suitable method Hot stage microscopy delivers valuable information about the thermal behavior of pharmaceutical samples by visually observing the sample appearance as a function of temperature and time. METTLER TOLEDO s HS82 and HS84 speed up this process and are very easy to operate. Text: Matthias Wagner Thermal Analysis Product Manager METTLER TOLEDO Pharma & Biotech News 10 7

8 Laboratory Automation Anne Swapped her Journal for LabX Be Next in Automating Your Worklflow Anne is a Laboratory Manager whose lab performs a wide variety of analyses, mostly for quality control purposes. Recently, Anne was tasked with finding a way to automate these analyses, optimize operators time and ensure traceability and compliance with the rising regulations. Anne concluded that the key needs were related to integration, either of instruments, systems, or reports, and automation of analyses, workflows, and data. She decided to adopt LabX in her laboratory to address these challenges. Today, her instruments are connected, methods started with just one click and lab journals replaced with a secure database.

9 Tailored set up Develop and implement SOP compliant application methods ready for use on the relevant instrument. Define the roles of individual users and set-up the daily task list. Smooth, error-free workflow On the instrument, step by step guidance directs the operator. All work is ensured to be in accordance with internal SOPs Full data management All information is automatically stored in a secure database to ensure traceability. See, store or print results in a customized report at any time. Power Your Bench with LabX Software Instrument connectivity LabX connects Mettler Toledo instruments to a single software. A unique interface means less training and more efficiency. Learn more a bout LabX

10 Product Highlight LabX Titration Power Your Titration Bench Titration joins the LabX family. Connect your METTLER TOLEDO instruments to LabX software and benefit from simplified operation, efficient method editing with the graphical layout, fast sample series modifications and tailored reports. LabX uniform software and interface means less training and also helps to increase your efficiency. Workbench Each instrument connected to LabX has its own workbench. It offers all the components needed to run your daily tasks and the tools to monitor your sample series and results. Flexible set-up LabX can be installed as single software or as a distributed system. Build up the system that suits your need and have access from any PC to LabX and your instruments in the laboratory. Single Software LabX connects your titrators, balances, density meters and refractometers, melting point instruments and Quantos systems. This means less training and also helps increase your efficiency METTLER TOLEDO Pharma & Biotech News 10

11 Worry-free Weighing with High Capacity Microbalances Micrograms of valuable and expensive materials are often weighed in the lab. Dosing into a larger container can reduce the minimum amount of sample weighed. However, a high capacity balance is needed in order to do so. The new XPE56 and XPE26 micro-analytical balances deliver high capacity coupled with minimum sample weights as low as 1.4 mg to save valuable material and still achieve maximum accuracy. Worry-free weighing The StaticDetect feature immediately warns if any relevant electrostatic charge is detected. StatusLight, a light on the balance s terminal, indicates if the balance is ready for weighing. Safe for operators The draft shield can be opened automatically for ergonomic left or right handed dosing, helping to speed up weighing processes. Draft shield and weighing pan fully dismantle for easy cleaning. Secure dosing With USP minimum weight as low as 1.4 mg and a capacity of up to 52 g, direct dosing into a tare container saves time and precious sample. The ErgoClips container holder makes dosing even easier. METTLER TOLEDO Pharma & Biotech News 10 11

12 Know-How Straightforward Routine Testing Minimize Risks and Costs Testing laboratory instruments periodically is not only a way of complying with regulations but also the key to obtaining accurate and reproducible results. Routine testing can be, however, a tedious and complex task. Our whitepapers provide you with recommendations about when and how to perform a routine testing on your instruments among other good practice tips! Step-by-step guidance for eased instrument routine testing Balances Pipettes Moisture Analyzers Mettler-Toledo AG Laboratory Division Im Langacher CH-8606 Greifensee, Switzerland For more information Local contact: