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<div class="container"><h1 class="title">Troubleshooting Carryover Peaks </h1> <div class="center"><img src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/nexera/troubleshooting-carryover-peaks/Carryover.jpg" alt="Troubleshooting Carryover Peaks"></div> <h3>With recent detector improvements, the sensitivity of today's detectors has allowed for the use of low concentration standards that are an order of magnitude lower than earlier ones.</h3> Carryover is a phenomenon that is dependant on the sample compound. A number of improvements to the injection process have greatly reduced the effects of carryover in the Shimadzu Prominence HPLC series. Installation of the optional, additional rinse pump provides a multi-liquid capability that reduces carryover to less than 0.0001% for the highly adsorptive chlorhexidine. <div class="ts-question">Are the carryover expectations realistic?</div> <div class="buttons"> <span class="btn-yes">[[Yes->Needle Position]]</span> <span class="btn-no">[[No->Rinse Descriptions]]</span> </div> </div>

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<div class="container"><h1 class="title">Needle Positions</h1> <div class="center"><img src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/nexera/troubleshooting-carryover-peaks/InjectionPort_0.jpg" alt="Carryover"></div> <h3>Carryover peaks are a bigger problem if the needle is not properly aligned with the injection port.</h3> Carryover is a phenomenon that is dependant on the sample compound. A number of improvements to the injection process have greatly reduced the carryover affects in the Shimadzu Prominence HPLC series. A specially treated outer needle surface and improvement of the needle seal composition greatly reduce sample adsorption in the Prominence series autosamplers. <div class="ts-question">Has needle position teaching been performed recently?</div> <div class="buttons"> <span class="btn-yes">[[Yes->Needle Seal]]</span> <span class="btn-no">[[No->Injection Port Adjustment]]</span> <span class="btn-back"><<back "Back">></span> </div> </div>

<div class="container"><h1 class="title">Rinse Descriptions</h1> <div class="center"><img src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/nexera/troubleshooting-carryover-peaks/RinsePort.jpg" alt="Rinse Port"></div> <h3>Some samples require stronger or more vigorous rinsing between samples.</h3> Depending on the viscosity of the sample solution, sample carryover from one injection to another can be a problem in HPLC analysis. The most common way of reducing this affect is by rinsing the sampling needle between samples. The Shimadzu Nexera series HPLC autosampler has a number of improvements that greatly minimize this affect, such as the addition of a specially coated needle and a change in the injection port design. It is also possible to add another rinse pump to the SIL-20 autosamplers to add the capability of an active rinse of the outer surface of the needle. Shimadzu autosamplers provide for a dip rinse of the outer surface of the needle. Now, with the addition of the Additional Rinse Pump it is possible to use two different rinse solvents and perform both the dip rinse and the active rinse. <div class="ts-question">Are the rinsing techniques and solutions adequate for the application?</div> <div class="buttons"> <span class="btn-yes">[[Yes->Gradient Profile]]</span> <span class="btn-no">[[No->RINSE MODE Parameter]]</span> <span class="btn-back"><<back "Back">></span> </div> </div>

<div class="container"><h1 class="title">Needle Seal</h1> <div class="center"><img src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/nexera/troubleshooting-carryover-peaks/NeedleSeal.jpg" alt="Troubleshooting Carryover Peaks"></div> <h3>The needle seal should be replaced after needle position teaching and after a large number of injections.</h3> The needle seal provides a leak-free injection port for introducing the sample into the HPLC system. The needle seal is a consumable item for the Prominence series of autosamplers. The needle seal should be replaced after about 40,000 injections. Use the NDL SEAL USED function (Maintenance Information group) to monitor the needle seal usage. Use the NDL Seal alert function (Calibration Support group) to set the level of needle seal usage that will cause an alarm to sound. The needle seal should be replaced after needle position teaching and after a large number of injections. <div class="ts-question">Has the needle seal been replaced recently?</div> <div class="buttons"> <span class="btn-yes">[[Yes->Rinse Descriptions]]</span> <span class="btn-no">[[No->Needle Seal Replacement - SIL-30AC]]</span> <span class="btn-back"><<back "Back">></span> </div> </div>

<div class="container"><h1 class="title">Injection Port Adjustment</h1> <div class="center"> <iframe width="900" height="506" src="https://www.youtube.com/embed/3Hgefu6z8ec?rel=0" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen></iframe></div> <img class="warning" style="float: left;" src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/virtual-advisor-warning-icon.png" alt="warning-icon"><strong>WARNING: During this adjustment procedure, operation does not stop when the door is open.To avoid injury, do not reach into the autosampler during this procedure. </strong> <ol> <li>From the Initial screen, press the VP button four times. The Calibration Support Group screen is displayed</li> <li>Press the FUNC key to display the Input PASSWORD screen.</li> <li>Enter the password (0,0,0,0,0) and press ENTER. The ADJUST MTP screen is displayed.</li> <li>Press FUNC until the Injection Port fine adjustment screen is displayed.</li> <li>Press ENTER. The needle moves to the front center position.</li> <li>Remove the thumbscrews that secure the clear front panel. Remove the clear front panel.</li> <li>Loosen the three thumbscrews that secure the Z-mount cover. Pull the Z-mount cover forward to remove it.</li> <li>Press ENTER. The Set New Position screen is displayed.</li> <li>Using the following keys, adjust the lateral and longitudinal needle position to align with the center of the top edge of the injection port.</li> <li>Press ENTER. The needle moves up and down about 2 mm.</li> <li>Enter the set value.</li> <li>Verify that the adjustment is correct and press 1. The needle moves back to the front center position.</li> <li>Re-attach the Z-mount cover.</li> <li>Press ENTER.The fine adjustment of the needle at the injection port is complete and the needle moves back to the injection port.</li> <li>Re-attach the clear front panel and secure it with the 5 thumbscrews.</li> <li>Press 1 to start the aging process. The Injecting screen is displayed.</li> </ol> <div class="buttons"> <span class="btn-back"><<back "Back">></span> </div> </div>

<div class="container"><h1 class="title">Gradient Profile</h1> <div class="center"><img src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/nexera/troubleshooting-carryover-peaks/GradientChange.jpg" alt="Gradient Change"></div> <h3>The gradient profile can greatly affect the retention of sample components.</h3> There are a number of ways to change the gradient profile that will aid in carryover reduction. *One way is by changing the lowest level of % organic to a higher level. This may keep any adsorption from occurring. *Another way is by extending the final hold time (highest % organic). This process extends the length of time that the organic level is at the highest, and washes adsorbed sample components away. <div class="ts-question">Is the gradient profile the best one for the compound of interest?</div> <div class="buttons"> <span class="btn-yes">[[Yes->Acidic Additive]]</span> <span class="btn-no">[[No->Entering the Gradient]]</span> <span class="btn-back"><<back "Back">></span> </div> </div>

<div class="container"><h1 class="title">RINSE MODE Parameter</h1> <div class="center"> <iframe width="900" height="506" src="https://www.youtube.com/embed/18SFhx0YEM8?rel=0" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen></iframe></div> The RINSE MODE parameter selects the needle rinsing method. <ul> <li>0 - No Rinsing</li> <li>1 - Rinsing before sample aspiration</li> <li>2 - Rinsing after sample aspiration</li> <li>3 - Rinsing before and after sample aspiration (default)</li> </ul> All the steps: <ol> <li>From the Initial screen, press the FUNC key. The Parameter setting screen is displayed.</li> <li>Press the ENTER key and then press the FUNC key twice. The RINSE MODE parameter screen is displayed.</li> <li>Enter the rinse mode number with the numeric keypad and press the ENTER key.</li> </ol> <span class="btn-link">[[RINSE VOLUME Parameter->RINSE VOLUME Parameter]]</span> <div class="buttons"> <span class="btn-back"><<back "Back">></span> </div> </div>

<div class="container"><h1 class="title">Acidic Additive</h1> <div class="center"><img src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/nexera/troubleshooting-carryover-peaks/SamplePreparation.jpg" alt="Sample Preparation"></div> <h3>Adding a weak acid to the sample solution and or rinse phase solution may coat any active sites in the system that could cause carryover.</h3> Active sites in the flow lines may cause sample target components to become strongly adhered to any of the surfaces they contact in the flow line. There are two general types of compounds that typically encounter adsorption problems. Ionic Compounds - These are typically acids and bases that are prone to adsorption to metal surfaces, such as stainless steel tubing and glass surfaces, such as vials and ceramic rotors. Hydrophobic compounds - These compounds are prone to adsorption to resin surfaces, such as Teflon. Rinsing and adding solvent additives are typical methods for handling the adsorption problem associated with active sites. <div class="ts-question">Have any acidic additives been added to the sample or rinse solution?</div> <div class="buttons"> <span class="btn-yes">[[Yes->Active Sites]]</span> <span class="btn-no">[[No->Sample and Rinse Solution Additions]]</span> <span class="btn-back"><<back "Back">></span> </div> </div>

<div class="container"><h1 class="title">Entering the Gradient</h1> <div class="center"><img src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/nexera/troubleshooting-carryover-peaks/GradientEnter.jpg" alt="Entering the Gradient"></div> Often, errors are made when entering gradient parameters. To ensure the use of a linear or step gradient, it is important that the parameters be entered correctly. Using the example above, re-examine the method and the gradient parameters to ensure that the gradient parameters have been entered properly. <div class="buttons"> <span class="btn-back"><<back "Back">></span> </div>

<div class="container"><h1 class="title">RINSE VOLUME Parameter</h1> <div class="center"> <iframe width="900" height="506" src="https://www.youtube.com/embed/035kyF0K6Ag?rel=0" title="RINSE VOLUME Parameter" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen></iframe></div> <img class="warning" style="float: left;" src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/virtual-advisor-warning-icon.png" alt="warning-icon"><strong>NOTE: If the rinse volume is set to [0], analysis time is reduced by omitting the purge operation for the measurement flow lines after sample injection.</strong> <br> <ol> <li>From the RINSE MODE screen, press the FUNC key twice. The RINSE VOLUME screen is displayed.</li> <li>Enter the numeric value for the parameter using the numeric keypad and press the ENTER key.</li> </ol> <span class="btn-link">[[RINSE MODE Parameter->RINSE MODE Parameter]]</span> <div class="buttons"> <span class="btn-back"><<back "Back">></span> </div> </div>

<div class="container"><h1 class="title">Active Sites</h1> <div class="center"><img src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/nexera/troubleshooting-carryover-peaks/Adsorb_ActiveSites.jpg" alt="Active Sites"></div> <h3>Active sites in the system may cause compounds to adhere temporarily before being washed off in a subsequent injection.</h3> It is important to be aware of the surfaces that the sample comes into contact with to ensure that the components of the flow line are non-reactive with the sample and mobile phase. A partial list of the surfaces that may contact the sample are listed below. <ul> <li>Sample preparation components (filters, pipettes, vials, etc.)</li> <li>Sample vial, septum and closure</li> <li>Sampling needle and sample loop</li> <li>Valve components</li> <li>Sample transfer tubing and tubing unions</li> <li>Column packing material</li> <li>Flow cell components</li> <li>Sample transfer tubing and tubing unions</li> </ul> PEEK tubing is generally more resistant to chemical adsorption than stainless steel. Active sites in the system may cause compounds to adhere temporarily before being washed off in a subsequent injection. <div class="ts-question">Is the sample reacting with active sites in the system?</div> <div class="buttons"> <span class="btn-yes">[[Yes->System Components]]</span> <span class="btn-no"><a href="/service-support/virtual-advisor/nexera/advanced-troubleshooting/troubleshooting-the-autosampler/index.html">Troubleshooting the Autosampler</a></span> <span class="btn-back"><<back "Back">></span> </div> </div>

<div class="container"><h1 class="title">Simple and Rinse Solutions Additions</h1> <div class="center"><img src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/nexera/troubleshooting-carryover-peaks/SamplePreparation.jpg" alt="Sample Preparation"></div> When a sample is subject to adsorption, it is important to select the solvent so the sample conditions suppress adsorption. Ionic Compounds - To suppress sample adsorption in acidic ionic compounds, sample solvents must be of a lower pH. (Acidify sample solvent with acetic, formic or perchloric acid as appropriate.) To suppress sample adsorption of basic ionic compounds, it is necessary to incorporate anions of large ionic radiuses. (Addition of TEA or a substance capable of reducing the surface tension of the sample solution.) Hydrophobic compounds - To suppress adsorption in hydrophobic compounds, use sample solvents with a lower polarity so the sample components will remain in solution through the analysis process. <div class="buttons"> <span class="btn-back"><<back "Back">></span> </div>

I had to merge rinse descriptions from two to one nodes

<div class="container"><h1 class="title">Needle Seal Replacement - SIL-30AC </h1> <div class="center"> <iframe width="900" height="506" src="https://www.youtube.com/embed/XN8uHCNKLmI?rel=0" title="Needle Seal Replacement - SIL-30AC" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen></iframe></div> <img class="warning" style="float: left;" src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/virtual-advisor-warning-icon.png" alt="warning-icon"><strong>CAUTION: If the needle seal cannot be removed from the housing, do not attempt to pull it out by force. Replace both the needle seal and the housing at the same time. Attempting to pull it out by force may result in injury.<br> CAUTION: When inserting the needle seal into the housing, hold the needle seal using a piece of soft cloth or paper, being careful not to allow dust to enter the hole. The entry of dust may create small gaps or voids that could lead to carryover or leaks. </strong> <ol> <li>Press [ZHOME Key] on the initial screen. The [ZHOME] screen is displayed.</li> <li>Press [enter] to move the needle up fully and to the center of the instrument.</li> <li>Turn OFF the power switch and disconnect the power cord.</li> <li>Open the doors.</li> <li>Remove the knurled thumbscrews (5) from the cooler cover.</li> <li>Pull on the cooler cover and remove it.</li> <li>Loosen the cap using the supplied needle seal XR installer / remover tool, and remove it.</li> <li>Use tweezers to remove the housing and the needle seal from the stator.</li> <li>Remove the needle seal from the housing. See CAUTION below.</li> <li>Insert the housing into the stator.</li> <li>Insert a new needle seal into the housing with the tapered hole on the needle seal facing upward. See CAUTION above.</li> <li>Finger-tighten the cap on the stator.</li> <li>Use the needle seal XR installer / remover tool to tighten the cap an additional 180°.</li> <li>Reinstall the sample cooler front panel.</li> <li>Secure the cooler panel with the knurled thumbscrews (5).</li> <li>Close the doors.</li> </ol> <span class="btn-link">[[Needle Seal Replacement - SIL-30AC MP->Needle Seal Replacement - SIL-30AC MP]]</span> <div class="buttons"> <span class="btn-back"><<back "Back">></span> </div> </div>

<div class="container"><h1 class="title">Needle Seal Replacement - SIL-30ACMP </h1> <div class="center"> <iframe width="900" height="506" src="https://www.youtube.com/embed/fNWy10xPRuc?rel=0" title="Needle Seal Replacement - SIL-30ACMP" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen></iframe></div> <img class="warning" style="float: left;" src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/virtual-advisor-warning-icon.png" alt="warning-icon"><strong>CAUTION: If the needle seal cannot be removed from the housing, do not attempt to pull it out by force. Replace both the needle seal and the housing at the same time. Attempting to pull it out by force may result in injury.<br> CAUTION: When inserting the needle seal into the housing, hold the needle seal using a piece of soft cloth or paper, being careful not to allow dust to enter the hole. The entry of dust may create small gaps or voids that could lead to carryover or leaks. </strong> <ol> <li>Press [ZHOME Key] on the initial screen. The [ZHOME] screen is displayed.</li> <li>Press [enter] to move the needle up fully and to the center of the instrument.</li> <li>Turn OFF the power switch and disconnect the power cord.</li> <li>Pull on the L-shaped faceplate to remove it.</li> <li>Open the key panel.</li> <li>Remove any sample racks.</li> <li>Open the rack door.</li> <li>Open the right and left doors.</li> <li>Remove the knurled thumbscrews (6) from the cooler cover.</li> <li>Pull on the cooler cover and remove it.</li> <li>Loosen the cap using the supplied needle seal XR installer / remover tool, and remove it.</li> <li>Remove the housing and the needle seal from the stator.</li> <li>Remove the needle seal from the housing. See CAUTION message.</li> <li>Insert the housing into the stator.</li> <li>Insert a new needle seal into the housing with the tapered hole facing upward. See CAUTION message.</li> <li>Replace and finger-tighten the cap on the stator.</li> <li>Use the needle seal tool to tighten the cap an additional 180°.</li> <li>Reattach the sample cooler cover and close all of the doors.</li> </ol> <span class="btn-link">[[Needle Seal Replacement - SIL-30AC->Needle Seal Replacement - SIL-30AC]]</span> <div class="buttons"> <span class="btn-back"><<back "Back">></span> </div> </div>

<div class="container"><h1 class="title">System Components</h1> <div class="center"><img src="https://www.ssi.shimadzu.com/sites/ssi.shimadzu.com/files/support/virtual-advisors/nexera/troubleshooting-carryover-peaks/SysComponents.jpg" alt="System Components"></div> It is possible that some of the materials in the flow line may react when they come into contact with the sample solution. A partial list of the surfaces that may need to be replaced is listed below. <ul> <li>Sample preparation components (filters, pipettes, vials, etc.)</li> <li>Sample vial, septum and closure</li> <li>Sampling needle and sample loop</li> <li>Valve components</li> <li>Sample transfer tubing and tubing unions</li> <li>Column packing material</li> <li>Flow cell components</li> <li>Sample transfer tubing and tubing solutions</li> </ul> PEEK tubing is generally more resistant to chemical adsorption than stainless steel. <div class="buttons"> <span class="btn-back"><<back "Back">></span> </div> </div>

Troubleshooting Carryover Peaks

With recent detector improvements, the sensitivity of today's detectors has allowed for the use of low concentration standards that are an order of magnitude lower than earlier ones.

Carryover is a phenomenon that is dependant on the sample compound.

A number of improvements to the injection process have greatly reduced the effects of carryover in the Shimadzu Prominence HPLC series.

Installation of the optional, additional rinse pump provides a multi-liquid capability that reduces carryover to less than 0.0001% for the highly adsorptive chlorhexidine.

Are the carryover expectations realistic?

Yes No

Nexera Virtual Advisor

Troubleshooting Carryover Peaks

With recent detector improvements, the sensitivity of today's detectors has allowed for the use of low concentration standards that are an order of magnitude lower than earlier ones.