I have noticed that more solution is used for reverse pipetting than for normal pipetting. What is the reason for this?

Reverse pipetting means uptake of liquid including the blow-out volume and dispensing of liquid without the blow-out volume. Reverse pipetting is recommended to reduce the error with viscous or foaming liquids or when dispensing very small sample volumes. The excess solution aspirated remains in the tip and is discarded.

What is reverse pipetting using an air-cushion pipette? Is there literature available?

Unlike forward pipetting, reverse pipetting involves pressing the pipette button to the second pressure point, allowing a greater volume to be aspirated into the tip. When dispensing liquid, there’s no pipette blow-out; instead, the residual liquid remains in the tip. This technique offers enhanced accuracy and precision for pipetting liquids with high viscosity or those prone to foam or produce bubbles. Eppendorf offers a variety of literature explaining the technique and proving application examples, such as the Userguide 020, several webinars, and YouTube videos.

What is pre-wetting using an air-cushion pipette, and is it volume-independent?

Regardless of the volume, the air cushion should be wetted by multiple filling and emptying of the tip before dispensing.

What are effective techniques for pipetting viscous liquids?

When pipetting viscous liquids, we recommend positive displacement instruments such as the Multipette (M4, E3, E3x). Those instruments offer the best dosing accuracy for viscous liquids due to the piston integrated into the tip. When handling viscous liquids with an air-cushion pipette (Research plus, Reference 2), be sure to pipette slowly and use reverse pipetting (see Userguide 020 or our extensive eBook on www.eppendorf.com/Pipetting-eBook for guidance). Additionally, adjust your pipette settings to account for differences in density by using the temporary adjustment. However, results will not match those achieved with a positive displacement device.

What is the best way to dispense organic solvent?

It is best to use a positive displacement device like the Multipette. Positive displacement devices are most suitable for precise and drip-free dispensing of liquids with high vapor pressure. As the liquid is enclosed in a tip with integrated piston, the solvent vapor does not come into direct contact with the instrument.

Are your pipettes free of nucleic acids?

We cannot guarantee that our pipettes are completely free of nucleic acids. While we maintain high standards of cleanliness and care during production, we do not implement specific measures to prevent nucleic acid contamination. To protect your samples from potential contamination, we recommend using positive displacement devices or filter tips, such as ep Dualfilter T.I.P.S. or ep Dualfilter T.I.P.S. SealMax.

When should I grease my Eppendorf pipettes?

The piston or cylinder in the lower part of the pipette should be relubricated after cleaning, decontamination, or exposure to grease-dissolving solutions such as organic solvents. Re-greasing your pipette after autoclaving is not necessary.

How should warm or cold liquids be pipetted?

Best Practices for Pipetting Warm or Cold Liquids: Warm and cold liquids can behave differently than those at room temperature, requiring adjustments in pipetting techniques. Temperature differences between the liquid and the pipette can affect the air cushion, resulting in inaccuracies and imprecision that may exceed permissible error limits. To achieve optimal results, ensure that the pipette, tips, liquid, and surrounding air are all at the same temperature. For enhanced accuracy and precision, consider using a positive displacement device like the Multipette M4 or E3/E3x.

Can the heat of my hand affect my pipetting result?

Modern pipettes address this issue by ensuring sufficient spatial separation between the piston and the handle. Additionally, the materials used in our pipettes support thermal shielding/isolation to prevent heat transfer from your hand (see Userguide 021).

Do Eppendorf pipettes always have to be kept in a stand or can they also be put down on the laboratory bench?

The pipette can be placed on the laboratory bench, but never with liquid inside the tip. In general, it is best to keep pipettes on the pipette carousel. When storing pipettes in a drawer, ensure the pipette does not come into contact with the drawer walls or other equipment, as this may damage the pipette when the drawer is opened or closed.

How can I adjust my air-cushion pipette for challenging liquids, long tips, or higher/lower altitudes?

Upon manufacturing, pipettes are calibrated to distilled water. Eppendorf mechanical pipettes allow temporary user adjustments, beneficial for liquids with different physical properties than water (density, viscosity, surface tension, vapor pressure), or when capillary actions occur (e.g., with DMSO). Adjustments are also beneficial when atmospheric pressure changes due to altitude or when using non-standard pipette tips (e.g., epT.I.P.S. long). The adjusted pipette delivers the correct volume only for the liquid used during adjustment. Please be aware that variable mechanical pipettes turn into "fixed-volume pipettes" when being adjusted. That means they can only be adjusted to a specific liquid to one volume and not across the entire dispensing range. Research plus and Reference 2 pipettes feature an adjustment window where the change can be monitored. It can be set back to factory settings "0". For detailed procedures and examples, refer to the operating instructions and Application Note No. 198. In contrast to mechanical pipettes, the electronic Xplorer/Xplorer plus pipettes can be adjusted for the entire range of volume. Additionally, the electronic pipettes offer several options for adjusting the pipette in the "Options" menu, e.g. to 75 % ethanol, altitude, elongated tips. Furthermore, individual adjustments are possible, as 1-point, 2-point or 3-point settings. For more information see User Guide 036. Temporary user adjustments can be reset to manufacturer settings without recalibration.

How do I determine the volume values when calibrating gravimetrically?

The most common method involves measuring the mass of distilled water (whose physical properties are known) using a balance, and then converting the mass to a volumetric value. This means that the measurement values from the analytical balance are multiplied by the correction factor Z (see SOP pipettes). This adjustment accounts for the density of water at the specific temperature and the relevant air conditions.

What does EN ISO 8655 cover?

ISO 8655-2022 is the global standard for piston-operated volumetric apparatus (POVA), including pipettes, burettes, dilutors, dispensers, and manual precision syringes, as defined by the International Organization for Standardization (ISO). It ensures standardized performance for manufacturers, calibration providers, and users.It is structured in 10 chapters: ISO 8655-1: Terminology, general requirements and user recommendations ISO 8655-2: Pipettes ISO 8655-3: Burettes ISO 8655-4: Dilutors ISO 8655-5: Dispensers ISO 8655-6: Gravimetric reference measurement procedure ISO 8655-7: Alternative measurement procedures ISO 8655-8: Photometric reference measurement procedure ISO 8655-9: Syringes ISO 8655-10: User guidance, user qualification and POVA qualification.

What do the terms random error and systematic error mean in a pipette calibration?

In pipette calibration, random error and systematic error are two key concepts that help ensure accuracy and precision in measurements. Random Error refers to the variability in measurements when the same volume is dispensed multiple times. It is also known as imprecision and is determined by calculating the repeat standard deviation of 10 measurements. These errors tend to scatter around the true value and can be minimized by consistent technique and proper training. Systematic Error is the consistent deviation of the measured volume from the selected/true volume, also known as inaccuracy and is determined by establishing the mean value of 10 measurements. Systematic errors can arise from defective or misadjusted devices and need to be corrected through proper calibration and maintenance.

Why are the Z factors listed in our SOP different from factors which can be derived from density reference values (of water)?

The Z factor is included in EN ISO 8655-6 and was incorporated into our SOP. As we understand it, it was incorporated in the standard by the Physikalisch Technische Bundesanstalt in Braunschweig. The Z factor describes the density of water at a particular temperature using a 5th degree polynomial. Furthermore, the density of water is corrected by the density of air (derived from air pressure) and a fixed correction value for balances. These corrections are the key reasons for the deviation from density values in various books of tables.

At which volumes should a variable pipette be calibrated?

According to the EN ISO 8655-2022 standard, three series of 10 measurements are used to calibrate a variable-volume pipette. The three test volumes are: 1. Nominal volume (the largest volume adjustable by the user, as determined by the manufacturer) 2. 50% of the nominal volume 3. 10% of the nominal volume, or the lower limit if the minimum is over 10%

What is the nominal volume of a variable pipette?

The nominal volume of a variable pipette is always its maximum volume. For a 100 - 1,000 µL pipette, this means 1,000 µL.

I very frequently work with different chemicals. Can I still perform pipette calibration using water?

As per EN ISO 8655-2022, pipette calibration, which involves checking liquid dispensed by the pipette on a balance, should always be performed using distilled or deionized water. If you are working with chemicals that have different properties than water, consider using the temporary adjustment to minimize errors as outlined in Application Note 198. In general, we recommend using direct displacement devices such as the Multipette M4/E3(x) for challenging liquids.

During weighing (pipette calibration) I obtained steadily decreasing measuring results. Why is this?

The weight fluctuations you measured would appear to be a temperature problem. Please ensure that the pipette, the distilled water used for testing, the tips etc. are all at the same temperature. It is recommended that the pipettes be placed in the weighing room at least 2 hours before the test is performed. While measuring, ensure that transfer of heat from your hands is kept to a minimum (otherwise weight fluctuations may occur!) Tip: do not constantly grasp the pipette in the palm of your hand while waiting for each measurement result! We recommend our standard operating procedure (SOP) for pipettes as a source of basic information on pipette calibration.

How are multi-channel pipettes tested?

According to ISO 8655-2022, every channel of a multi-channel pipette must be tested. While all channels need to be filled, only the channel being tested is measured. Due to the high number of measurements required (e.g., 240 measurements for an 8-channel pipette and 360 measurements for a 12-channel pipette), it is advisable to send the multi-channel pipette to a professional calibration lab. These labs are equipped with specialized balance setups that ensure all channels are filled while only one channel is measured at a time.

Is the pipette grease free of resins?

Yes, the pipette grease supplied by Eppendorf is free of resins.

How many times can Reference 2 be autoclaved?

Our pipettes are checked for a minimum lifetime of five years. This means a normal use with 200,000 strokes, 26,000 volume changes, 100,000 tip ejections, and 175 autoclavings without the pipetting results and pipette material being affected.

The housing of Reference 2 contains different materials. What effects does this have on the pipette during autoclaving?

The Reference 2 is mounted in a way that all materials have room for expansion. Furthermore, only materials are used which are resistant to severe conditions, e.g. autoclaving (pressure, rise in temperature).

Is it possible to deactivate the spring-loaded tip cone of a Reference 2 multi-channel pipette?

Yes. The Reference 2 multi-channel pipettes have a switch on the lower part which deactivates/activates the spring-loaded tip cone.

How often should pipettes be calibrated?

The user determines the frequency of calibration. However, according to EN ISO 8655-2022 Part 1, calibration must be performed regularly and at a minimum, once per year. Routine tests should be performed more frequently, ideally at intervals shorter than those for calibration. The frequency of both calibration and routine tests should be established through a risk assessment. This assessment needs to consider factors such as the frequency of pipette use, the number of users, the aggressiveness of the liquids being dispensed, and the acceptable error limits set by the user. Additionally, any industry- or organization-specific frequency requirements must be adhered to.

What material is my pipette made of and what chemicals is it resistant to?

Please refer to the Operating Manual on our homepage for information on material or chemical resistance before use. The Research plus and Reference 2 have separate chemical resistance sheets. Please note that aggressive chemicals used over a longer period of time may shorten the lifetime of the pipette.

Is it possible to inactivate the spring-loaded tip cone of a single-channel pipette?

Yes, the delivery includes a locking ring to easily deactivate the spring-loaded tip cone. Disassemble the upper from the lower part of the pipette and push the locking ring onto the lower part from the top. Refer to the Operating Manual for an illustrated guide. This is useful for pipette tips not designed for Eppendorf pipette cones.

What is the difference between factory setting and user adjustment?

Eppendorf pipettes offer factory adjustment and temporary adjustment. The temporary adjustment is an easy way of adjusting the pipette temporarily to different conditions (e.g. pipetting a liquid with high density). The factory adjustment should be changed if the pipette was found to be out of specifications during calibration. Before adjusting, exclude other causes such as pipette handling, environmental errors, or worn-out parts.

text.skipToContent text.skipToNavigation

JP | JPY

Sorry, we couldn't find anything on our website containing your search term.

Eppendorf Reference^® 2

Eppendorf Reference® 2シングルチャンネルピペット、8チャンネルまたは12チャンネルを選択可能

Eppendorf Reference 2マルチチャンネルの下部にあるスプリング式チップを「オン/オフ」スイッチで無効化

Eppendorf Reference® 2 multi-channel pipette family

epT.I.P.S.®マクロ容量チップで 15 mL遠心管やフラスコなどの下部に簡単にアクセス可能

Pipette Carousel 2で、最大6つのEppendorfピペット用スペース

製品情報

Eppendorf Reference 2機械式ピペットを選択すると、操作労力を軽減しながら、その高精度と正確度のメリットを享受できます。スムーズな表面とオートクレーブ滅菌の可能性は効率的な除染を保証します - 滅菌条件で作業する場合に理想的なコンパニオンです。固定容量または可変容量でシングルチャンネルピペットとして、また8チャンネルと12チャンネルピペットとして使用できます - すべて時間を節約するシングルボタン操作付きです。このユニークな操作フィロソフィを一度経験すると、もう元には戻りたくないと思うでしょう！

製品情報をもっと見る

追加でダウンロードできる材料がありますこのページの最後に

製品情報

アプリケーション

特徴

優れた精度と正確度を誇るプレミアムピペット

Eppendorf Reference 2優れた精度と正確度を持つ機械式エアクッションは極めて信頼性があり、頑丈、また長持ちします。ユニークなシングルボタン操作で、Reference 2は迅速で人間工学的なハンドリングが可能、また操作が簡単、アクティブエアロゾルを軽減します。明確な触覚フィードバックにより、不慮のチップ排出を防ぐことができます。品質と再現性に妥協しない－貴重なを安心して高い正確性でピペッティングし、結果を向上させるには、Eppendorf Reference 2をお選びください。
ステンレス製の堅牢なハンドルはピペットを衝撃から保護し、バネ式バンパーとの組み合わせでReference 2ピペットは落下しても較正公差内に留まる確率が極めて高いです。これらの高度なセキュリティにより、Reference 2は極めて高精度が求められるアプリケーションに最適なパートナーとなります。

迅速に行える人間工学に基づいたワンボタン操作

精密なEppendorf Reference 2ピペットを使用すると、吸引、分注、チップ排出の操作力が低くなるため、負担が軽減されます。また、チップを取り出すために親指を左右に動かす必要がないため、操作時間が短縮され、ピペッティング作業を素早く進めることができます。また、チップが分注後すぐに排出されるので、ピペットのエアロゾル汚染も軽減するというメリットもあります。

使いやすい一時的調整オプション

確実に試料のタイプによってピペットを調整することが重要です。 Reference 2機械的ピペットなので、工場設定を妨げることなく行うことができます。一時的でシンプルな調整は、さまざまな液体の正確なピペッティングを行うためにReference 2を変更することを容易にします。推奨設定はマニュアルに記載されており、即座に簡単にメーカー設定にリセットできます。

無菌作業環境における理想的な実験室コンパニオンです

Reference 2 ピペットは簡単に分解でき、完全にオートクレーブ可能で、1 回の注入で滑らかなハウジングが作られるのが特徴です。これは、細菌汚染を懸念する研究者にとって利点となります。表面の粘着性が低く、空洞、溝、摺動部品が最小限に抑えられているため、Reference 2 は除染が容易で、クラス A/B クリーンルームやその他の無菌環境での使用に特に適しています。

選ぶのはあなたです。弊社では、シングルチャネルとマルチチャネルのさまざまなオプションを提供しています。

すべての実験が同じ作業条件を基にしているわけではありません。容器のタイプによって、チューブとフラスコに理想的なシングルチャンネルReference 2ピペットを選び、プレートにはより良く合うマルチチャンネルReference 2ピペットを選びます。

• チューブとフラスコ: シングルチャンネルの選択肢、可変容量または固定容量ピペットとして利用可能
• 96と24ウェルプレート： スプリング式チップコーンを無効にするオプションを備えた 8 チャンネルおよび 12 チャンネルのピペットを選択できます。

疲れない人間工学的ピペッティング

ユニークなシングルボタンの操作でEppendorf Reference 2ピペットは革新的で優れた人間工学的操作コンセプトを特徴とします。それは、手と腕の緊張を最小化するためにEppendorf PhysioCare Concept ^®が備わったラインで設計されたものです。ほとんどの他のEppendorfピペット、Reference 2プレミアムピペットにはもちろん Eppendorfのスプリング式チップコーンとSoftEjectテクノロジーが装備されています。

信頼性の高いチップのフィットおよび低いチップ取り付け力のためのばねバネ式ノーズコーン

バネ式ノーズコーンを備えた Eppendorf ピペットは、エネルギーと時間を節約します。触覚フィードバックにより、軽く 1 回押すだけでチップを簡単に取り付けることができます。スプリングリミットアタッチメントと排出は再現性のある安全なチップのフィットを強制して保証します。この賢い設計により、ユーザー対ユーザーの再現性が向上し、異なる実験室メンバー間でより一貫した結果が得られます。 Eppendorf から 1,000 µL までのすべてのマイクロピペット（Move It^® 300 µL モデルを除く）には、バネ式ノーズコーン機能が装備されています。すべての Reference 2 マルチチャンネルピペットでは、ピペットのボトムパーツの「オン/オフ」スイッチを使用してスプリングを簡単に無効にすることができます。

SoftEjectテクノロジーによりチップ排出力が50 %減少

Eppendorfのすべての非調整式マルチチャンネルピペットは、革新的なSoftEjectテクノロジーを使用して、各チップ排出ストローク中に外側のチップが内側のチップより先に排出されるようにします。これはユーザーにはわかりませんが、チップ排出力が 50 % 減少します。イジェクトボタンをわずかに1回押すだけで、自動的にチップが連続して排出されます。