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FLOW CYTOMETRY

flow cytometry reinvented

The Attune

®

Acoustic Focusing Cytometer

Precision and sensitivity at all speeds for rare events

and precious samples

(2)

The Attune

®

Acoustic Focusing Cytometer

• Precise—high collection rates without compromising CVs

• Fast—rare-event detection with dramatically shorter acquisition times

• Simple—no-lyse, no-wash method eliminates cell loss

With the Attune

®

Acoustic Focusing Cytometer, you get both high sample input rate and high precision when analyzing

precious samples or detecting rare events. You control your sample concentration, flow rate, the number of photons you

detect, the length of your experiment, and more. You get the most out of your cells with dependable results. But best of all,

the Attune

®

cytometer makes it easy.

Precision and sensitivity at all sample throughput rates

The Attune

®

Acoustic Focusing Cytometer enables higher sensitivity when you need it most. You’ll be able to maintain precise

alignment, even at high sample rates of up to 1 mL/min. And because the Attune

®

cytometer is not limited by physical sheath

flow constraints, you can control the amount of time cells spend in the lasers’ path. This means you can use a slower rate to

collect more photons when analyzing dim signals, translating to better clarity of your results and better separation (Figures 1

and 2).

Figure 1. Greater peak separation with phosphospecific antibody staining. Intracellular target detection can be challenging. Jurkat T cells were stimulated with anti-CD3 and anti-CD28 antibodies, then fixed and permeabilized before staining with a PE-labeled phosphospecific antibody. The sample was run on the Attune® cytometer and a hydrodynamic focusing cytometer and the data compared. The plots show an overlay of the data from stimulated and unstimulated samples from each system. The data obtained with the Attune® Acoustic Focusing Cytometer have higher precision (narrower peaks), resulting in greater separation and easier data interpretation.

Hydrodynamic

focusing

instrument

66.58% 0 102 103 104 105 60 40 20 0 Count PE-A

Attune

®

cytometer,

normal

sensitivity

mode

81.49% 0 102 103 104 105 100 80 40 20 0 % of Max 60 BL2-A:BL2-A Note: increased precision as seen by the tighter populations.

Hydrodynamic

focusing

instrument

66.58% 0 102 103 104 105 60 40 20 0 Count PE-A

Attune

®

cytometer,

normal

sensitivity

mode

81.49% 0 102 103 104 105 100 80 40 20 0 % of Max 60 BL2-A:BL2-A Note: increased precision as seen by the tighter populations.
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Figure 2. Sensitivity through control of cell transit times. Fluorescent microspheres (Spherotech Rainbow 3.2 μm) were run on a high-end conventional flow cytometer and on the Attune® Acoustic Focusing Cytometer using a 488 nm blue laser (top row) and a 405 nm violet laser excitation (bottom row). The conventional flow cytometer was run at its highest sensitivity setting, at a sample input rate of 15 μL/min (left column). The Attune® cytometer was run at 2 different settings: at its standard sensitivity setting, at a 100 μL/min sample input rate (middle column), and at its highest sensitivity setting, with a 100 μL/min sample input rate and 4x increase in the amount of time the particles are illuminated by the laser (right column). The Attune® cytometer standard settings resulted in sensitivity equal to or better than the conventional flow cytometer, while the high sensitivity of the Attune® instrument resulted in detection of the faintest beads not detected by the conventional flow cytometer.

Conventional flow cytometer

(Highest sensitivity setting) Attune(Standard sensitivity setting)® cytometer Attune(High sensitivity setting)® cytometer

675 LP 675 LP 675 LP 585/42 585/42 585/42 101 102 103 104 105 PE-Cy®5 101 102 103 104 105 Pacific OrangeTM 101 102 103 104 105 106 PE-CyT®5 101 102 103 104 105 106 Pacific OrangeTM 101 102 103 104 105 106 PE-Cy®5 101 102 103 104 105 106 Pacific OrangeTM 0 56 111 167 222 Count 0 54 108 167 216 Count 0 106 211 317 422 Count 0 59 117 176 234 Count 0 106 212 318 424 Count 0 76 161 227 302 Count

Conventional flow cytometer

(Highest sensitivity setting) Attune(Standard sensitivity setting)® cytometer Attune(High sensitivity setting)® cytometer

675 LP 675 LP 675 LP 585/42 585/42 585/42 101 102 103 104 105 PE-Cy®5 101 102 103 104 105 Pacific OrangeTM 101 102 103 104 105 106 PE-CyT®5 101 102 103 104 105 106 Pacific OrangeTM 101 102 103 104 105 106 PE-Cy®5 101 102 103 104 105 106 Pacific OrangeTM 0 56 111 167 222 Count 0 54 108 167 216 Count 0 106 211 317 422 Count 0 59 117 176 234 Count 0 106 212 318 424 Count 0 76 161 227 302 Count

Conventional flow cytometer

(Highest sensitivity setting) Attune(Standard sensitivity setting)® cytometer Attune(High sensitivity setting)® cytometer

675 LP 675 LP 675 LP 585/42 585/42 585/42 101 102 103 104 105 PE-Cy®5 101 102 103 104 105 Pacific OrangeTM 101 102 103 104 105 106 PE-CyT®5 101 102 103 104 105 106 Pacific OrangeTM 101 102 103 104 105 106 PE-Cy®5 101 102 103 104 105 106 Pacific OrangeTM 0 56 111 167 222 Count 0 54 108 167 216 Count 0 106 211 317 422 Count 0 59 117 176 234 Count 0 106 212 318 424 Count 0 76 161 227 302 Count

Conventional flow cytometer

(Highest sensitivity setting) Attune(Standard sensitivity setting)® cytometer Attune(High sensitivity setting)® cytometer

675 LP 675 LP 675 LP 585/42 585/42 585/42 101 102 103 104 105 PE-Cy®5 101 102 103 104 105 Pacific OrangeTM 101 102 103 104 105 106 PE-CyT®5 101 102 103 104 105 106 Pacific OrangeTM 101 102 103 104 105 106 PE-Cy®5 101 102 103 104 105 106 Pacific OrangeTM 0 56 111 167 222 Count 0 54 108 167 216 Count 0 106 211 317 422 Count 0 59 117 176 234 Count 0 106 212 318 424 Count 0 76 161 227 302 Count

Conventional flow cytometer

(Highest sensitivity setting) Attune(Standard sensitivity setting)® cytometer Attune(High sensitivity setting)® cytometer

675 LP 675 LP 675 LP 585/42 585/42 585/42 101 102 103 104 105 PE-Cy®5 101 102 103 104 105 Pacific OrangeTM 101 102 103 104 105 106 PE-CyT®5 101 102 103 104 105 106 Pacific OrangeTM 101 102 103 104 105 106 PE-Cy®5 101 102 103 104 105 106 Pacific OrangeTM 0 56 111 167 222 Count 0 54 108 167 216 Count 0 106 211 317 422 Count 0 59 117 176 234 Count 0 106 212 318 424 Count 0 76 161 227 302 Count

Conventional flow cytometer

(Highest sensitivity setting) Attune(Standard sensitivity setting)® cytometer Attune(High sensitivity setting)® cytometer

675 LP 675 LP 675 LP 585/42 585/42 585/42 101 102 103 104 105 PE-Cy®5 101 102 103 104 105 Pacific OrangeTM 101 102 103 104 105 106 PE-CyT®5 101 102 103 104 105 106 Pacific OrangeTM 101 102 103 104 105 106 PE-Cy®5 101 102 103 104 105 106 Pacific OrangeTM 0 56 111 167 222 Count 0 54 108 167 216 Count 0 106 211 317 422 Count 0 59 117 176 234 Count 0 106 212 318 424 Count 0 76 161 227 302 Count

Table 1. Comparison of acquisition times with a hydrodynamic focusing cytometer or the Attune® Acoustic Focusing Cytometer, using a blood sample from an aplastic anemia individual, each with a stop gate set on 1 million granulocyte events.

Instrument (collection rate) Time to acquire 1 million granulocyte events Relative rate compared to hydro-dynamic focusing Hydrodynamic focusing

cytometer (high) 63 min 33 sec –

Attune® Acoustic Focusing

Cytometer (200 µL/min) 13 min 20 sec 4.8x faster Attune® Acoustic Focusing

Cytometer (500 µL/min) 5 min 47 sec 11.0x faster Attune® Acoustic Focusing

Cytometer (1,000 µL/min) 3 min 13 sec 19.7x faster

Rare events detection 10 times faster

The Attune

®

Acoustic Focusing Cytometer achieves sample throughput at rates over 10 times faster than other cytometers—

up to 1,000 µL per minute, enabling rapid detection of rare events with reliable accuracy while aborting no data (Table 1,

Figure 3). The Attune

®

cytometer is designed to collect up to 20 million events per run and has adjustable collection rates of

25–1,000 µL/min.

CD317-Alexa Fluor® 488 fluorescence

102 103 104 105 106 Gated on live CD19

-cells at collection rate of 500 ul/min

C D 45 R /B 22 0-P E fl uo re sc en ce 106 105 104 103 102

Figure 3. Collecting more than 1 million live cells and detecting a rare population of dendritic cells of 0.2% with mouse splenocytes. Plasmacytoid dendritic cells (pDCs) are a specialized cell population that produces large amounts of type I interferons in response to viruses and are identified using the immunophenotype CD19–, B220high, CD317+. Four-color staining of mouse splenocytes included CD19 Pacific Blue, CD317 Alexa Fluor® 488, CD45R/B220-PE direct conjugates, and SYTOX® AADvancedTM Dead Cell Stain. A gate was made on live cells using SYTOX® AADvancedTM Dead Cell Stain, followed by gating on CD19 cells. A two-parameter plot of CD45R/B220 vs. CD317 was used to identify pDCs. A collection rate of 500 µL/min was used to acquire 1.3 million total cells with a cell concentration of 7.5x10^7 cells/mL. Plasmacytoid dendritic cells were identified as dual B220+/CD317+ (upper right quadrant) and constitute 0.851% of live CD19 cells, which is 0.194% of total splenocytes.

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CD34 8 7 6 5 4 3 2 1 0 105 102 103 104 101 106 CD34+

Attune® sample rate: 1,000 µL/min

SSC Figure 4. Identification of CD34+ cells from peripheral blood. Peripheral blood from a normal donor was stained and run on the Attune® Acoustic Focusing Cytometer at a collection rate of 1,000 μL/min with a stop gate set at 500,000 total cells. A rare population of 0.045% CD34+ cells (red box) was identified within the population of cells with an acquisition time of 4 minutes, 28 seconds.

Table 2. Comparison of absolute cell counting with a hydrodynamic focusing cytometer or the Attune® Acoustic Focusing Cytometer. Instrument Sample Flow Rate (µL/

min) Acquisition Time Percentage of CD34

+

Cells CD34

+ Cells/µL, Direct

Measurement

Attune® Acoustic Focusing Cytometer 1,000 4 min, 28 sec 0.05% 0.05

High-end conventional cytometer 60 13 min, 46 sec 0.02% N/A

Dilute your samples, not your data quality

Washing and lysis of red blood cells (RBCs) can cause significant cell loss and damage [1]. Significantly higher sample

collection rates allow the Attune

®

cytometer to deliver a no-wash, no-lyse protocol to minimize cell loss and simplify

sample preparation (Figure 5). This feature is particularly useful for samples that are inherently low in concentration.

Dilute samples like cerebrospinal fluid (CSF), stem cells, and any sample with low cell numbers can take a long time to

acquire.

With the Attune

®

cytometer, even dilute samples can be acquired quickly without compromising data. Difficult-to-collect

samples like mouse blood and bone marrow, thin-needle aspirates, or any sample with low cell yield can be stained and

then diluted without washing or performing RBC lysis. High rate collection makes acquisition possible—you can run up

to 4 mL in just four minutes. No sample loss occurs from sample preparation, and full panel testing is possible for all

precious samples.

Figure 5. Eliminating sample preparation without compromising data. Normal whole blood (100 µL) was labeled with CD45 Pacific Blue™, CD3 Alexa Fluor® 488, and CD4 PerCP-Cy®5.5 direct conjugates. After 15 minutes of incubation, 5 µL of the stained whole blood was diluted into 4 mL PBS, and data were acquired on the Attune® cytometer without RBC lysis or washing. A fluorescence threshold was set on the Pacific Blue™ dye to include only CD45-positive cells. A gate was created around the lymphocyte population in a CD45 vs. SSC plot (A) to analyze the mutually exclusive CD4 and CD8 populations (B). By diluting the sample and using a rate of 500 µL/min, all sample preparation steps can be eliminated without compromising the data.

In addition, the

Attune®cytometer

provides direct cell counts without the need for expensive counting beads with volumetric

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9 8 7 6 5 4 3 2 1 0 C-L ow (12 µL/min)

C-Med (35 µL/min) C-High (60 µL/min) Attune

® (25 µL/min) Attune ® (100 µL/min) Attune ® (200 µL/min) Attune ® (500 µL/min) Attune ® (1,000 µL/min) GO/G1 CV %CV 60 µL/min 1,000 µL/min 25 µL/min Low - 12 µL/min Medium - 35 µL/min High - 60 µL/min A B C D E F High-End Hydrodynamic

Focusing Cytometer Attune

® Acoustic

Focusing Cytometer

200 µL/min

1,000 µL/min

Figure 6. Minimal data variation at high sample rates with the Attune® Acoustic Focusing Cytometer. Jurkat cells were fixed and stained with propidium iodide, treated with RNase, and analyzed at a concentration of 1 x 106 cells/mL on a high-end instrument that uses hydrodynamic focusing, and on the Attune® Acoustic Focusing Cytometer at different sample rates. The left peak in all graphs reflects cells in G0/G1 phase, while the right peak reflects cells in G2/M phase. Note that as sample rates increase on the instrument that uses hydrodynamic focusing, the width of the G0/ G1 and G2/M peaks increase, whereas for the Attune® cytometer the peaks are relatively stable, even at the highest sample rate of 1,000 µL/min.

Figure 7. Percent CV of G0/ G1 at different flow rates on the Attune® cytometer and a competitor (C) at differ-ent sample rates. Note the minimal change in variability (%CV) for the Attune® Acoustic Focusing Cytometer, even at a high sample rate.

Cell cycle analysis is just one example of where it is critical to

precisely detect differences in fluorescence intensity between

multiple cell populations. With the Attune

®

Acoustic Focusing

Cytometer, minimal variation in results is seen regardless

of sample throughput rate. You no longer need to sacrifice

throughput for sensitivity (Figure 6).

• Minimal variation, even at high sample rates

(Figures 6 and 7)

• Less variability in results

(see changes in %S phase from Table 1)

• No sacrifice of sensitivity for speed

Attune® Acoustic G0G1 CV = 3.11% Hydrodynamic System G0G1 CV = 3.35% Hydrodynamic System G0G1 CV = 5.53% Hydrodynamic System G0G1 CV = 6.10% A B C D E F Ramos B Cells KG-1 a Myeloblast Cells HL60 Promyeloblast Cells

U266 Myeloma Cells

ST486 B Cells Attune® Acoustic G0G1 CV = 2.14% Hydrodynamic System G0G1 CV = 7.17% G H Attune® Acoustic G0G1 CV = 4.41% Hydrodynamic System G0G1 CV = 5.84% I J Attune® Acoustic G0G1 CV = 2.81% Attune® Acoustic G0G1 CV = 3.58%

Figure 8. Attune® Acoustic Focusing Cytometer exhibits greater precision. Data collected on the Attune® cytometer exhibits lower coefficients of variation (%CV) and more distinct cell populations when compared to a high-end hydrodynamic focusing flow cytometer.

Five other cell types were compared to a high-end

hydrodynamic focusing cytometer, including ModFit

analysis in each case. The sample throughput rate

of 25uL/min was used for the analysis (Figure 8).

Cell cycle analysis using the Attune

®

Acoustic

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Hydrodynamic core

Laser (cross-section)

sheath sheath sheath sheath

B. Traditional hydrodynamic focusing: compromised of data quality

device sheath sheath sheath Acoustically focused sample stream Laser (cross-section) A. Acoustic focusing = better precision

sheath

What is acoustic focusing cytometry?

The Attune

®

Acoustic Focusing Cytometer is the first cytometer that uses ultrasonic waves (over 2 MHz, similar to those used

in medical imaging), rather than hydrodynamic forces, to position cells into a single focused line along the central axis of a

capillary (Figure 9). Acoustic focusing is largely independent of the sample input rate, enabling cells to be tightly focused at

the point of laser interrogation regardless of the sample-to-sheath ratio (Figure 10). This, in turn, allows slowed cell velocity to

collect more photons for high-precision analysis at unprecedented volumetric sample throughput.

The Attune

®

cytometer accomplishes all this without high velocity or high volumetric sheath fluid, which can damage cells.

In addition, volumetric syringe pumps enable absolute cell counting without beads—minimizing cost and sample preparation

time. In contrast, cytometers that use hydrodynamic focusing maintain the same sample speed at all flow rates, causing cells

to lose focus as the sample core widens to increase flow rate.

Figure 9. Acoustic focusing in action. Fluorescent microspheres were applied to the capillary system of an acoustic focusing cytometer. Beads flow through randomly without any acoustic focusing (left). With the application of acoustic focusing, the beads are focused into a single line (right).

Acoustic focusing = OFF Sample is unfocused

Acoustic focusing = ON Sample is focused

No more tradeoffs

Hydrodynamic focusing cytometers have many limitations. As a result, users often have to sacrifice:

• Throughput for sensitivity • Features for ease of use • Performance for price • Power for footprint

Acoustic focusing technology keeps cells within a confined focal point, so these tradeoffs are not required.

Figure 10. Acoustic focusing vs. traditional hydrodynamic focusing. (A) In acoustic focusing, cells remain in tight alignment even at higher sample rates. With this tight alignment, cells pass through the laser beam at its optimal focal point, resulting in less signal variation and improved data quality. (B) In traditional hydrodynamic focusing, increasing the sample rate results in widening of the sample core stream. The speed at which cells pass through the laser is not changed, and is determined by the speed of the sheath fluid flow. Cells are distributed throughout the sample core stream because of reduced differential pressure between sample stream and sheath stream, resulting in reduced cell focusing. Cells are not in tight alignment as they pass through the laser beam, resulting in increased signal variation and compromised data quality.

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Ideal for both standard and specialized research applications

Most standard applications for flow cytometry have been tested on the Attune

®

cytometer, including:

• Live/dead cell discrimination

• Cell cycle analysis

• Cell proliferation assays

• Basic phenotyping (up to 6 colors)

• Rare-event detection

• Apoptosis

• Phagocytosis

• Detection of phosphoproteinsPhagocytosis

• Other intracellular markers

• Jurkat cells

• HL60 promyoblast cells

• U266 myeloma cells,

• Mouse splenocytes

• Mouse blood

• HeLa human cervical carcinoma cells

• Bovine pulmonary artery epithelial (BPAE) cells

• 3T3 mouse embryo fibroblast cells

• Chinese hamster ovary (CHO) cells

• Human mesenchymal stem cells (hMSC)

• E. coli, S. aureus

• H

uman platelets

• H

uman whole blood

Many standard cell types have been tested, including:

Data have also been collected in specialized research areas such as oceanography and microbiology. Cells up to 100 μm in

diameter have been run without clogging our 200 μm flow cell, with a minimum particle size specification of 1 μm; however,

researchers are constantly pushing these limits with the Attune

®

cytometer.

Service and support

The Attune

®

Acoustic Focusing Cytometer is backed by Life Technologies’ worldwide technical support and service programs.

We are focused on delivering personalized service from the time our sales representative walks through the door and

throughout the life of your Attune

®

instrument. The Attune

®

cytometer is fully supported for one year with our extensive service

plan, which includes:

• Comprehensive training

• Application and assay support

• Worldwide technical service

• Preventive maintenance

Extended service plans are also available. For more information about available service plans, go to

www.appliedbiosystems.com/attunecytometer

1. Gratama JW, Menéndez P, Kraan J, Orfao A (2000) Loss of CD34(+) hematopoietic progenitor cells due to washing can be reduced by the use of fixative-free erythrocyte lysing reagents. J Immunol Methods 239:13–23.

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Attune

®

Acoustic Focusing Cytometer

Software that performs to your specifications

User-defined analysis, flexible setup

Attune

®

Cytometric Software is designed to provide powerful user-defined analysis using an intuitive interface for

simplified experimental analysis (Figure 11). Templates can be built around specific applications and saved for consistent

experimental design. Compensation is automated or user-defined and can be set up using a compensation guide. Utilities

such as quick-save, drag-and-drop, and copy-and-paste provide rapid manipulation with commonly used functions.

Experiments can be easily set up with automated settings that can be completely customized and saved for future

experiments.

No software licensing fees

The Attune

®

Cytometric Software can be downloaded without licensing fees. The software can be added to any desktop

or laptop computer at your institution without any additional costs. Results can easily be analyzed at your convenience at

your own computer, allowing the next user to run experiments on the Attune

®

cytometer.

Instrument controls • Instrument status • Control sample flow rate • Select sensitivity level • Run startup/shutdown

protocol

• System performance tracking by date

Visualization tools

• Plot overlay or side-by-side graph comparison

• Standard or custom gate shapes

• Histograms, dot plots, density plots

• Customize statistics • Copy and paste plots into

reports (Microsoft® Word® or

PowerPoint® software)

Analysis setup

• Save protocol templates • Automated or user-defined

compensation • Raw data capture

• Data display in linear, log, or lin/lg scales

• Set universal compensation across multiple data sets

File format compatibility • Save data and images in

PDF format for reports • Data format in standard

FCS 3.0 for compatibility with third-party analysis tools (i.e., FlowJo, ModFit LT™, FCS Express

software programs) • Statistics in .csv format

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Instrument performance tracking

The Attune

®

Cytometric Software provides automated baseline calculation and performance test functions with minimal

user interactions. Performance tracking is facilitated through the reports function in the software.

Instrument performance tracking is critical for collecting and analyzing accurate experimental data. The Attune

®

Performance Tracking Beads are designed for use with the Attune

®

Cytometric Software to automatically characterize,

track, and report performance measurements of the Attune

®

Acoustic Focusing Cytometer (Figure 12). The beads

are used to define a baseline and conduct daily measurements of the cytometer. Vials contain enough beads for 50

measurements, and specific information for each lot is downloaded to the Attune

®

Cytometric Software prior to use.

Performance tracking for the Attune

®

cytometer includes a comprehensive set of procedures to monitor the daily

performance of the instrument. The performance tracking process involves:

• Running performance tracking beads

• Monitoring changes in the coefficient of variation and in the associated PMT voltage

• Tracking linearity of instrument performance

• Evaluating the detector sensitivity and background over time

• Automatic setting of laser delay

Instrument performance is affected by the lasers, optics, and fluidics of the instrument. For optimal instrument

performance, it is critical to follow the manufacturer’s recommended schedules for maintenance.

Figure 12. Example of Levey-Jennings plot showing Attune® cytometer performance over time. This report is generated using data from performance tracking beads.

Figure 11. Example of Attune® Cytometric Software. The instrument control panel on the left side of the screen is used for experiment setup and control of laser selection, optics, and fluidics (flow rates). The main frame of this screen shows data analysis plots, while the right panel shows sub-file organization.

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www.lifetechnologies.com

Life Technologies offers a breadth of products DNA | RNA | PROTEIN | CELL CULTURE | INSTRUMENTS For Research Use Only. Not intended for any animal or human therapeutic or diagnostic use.

LIMITED USE LABEL LICENSE: No right to resell this product or any of its components is conveyed expressly, by implication, or by estoppel. For information on obtaining additional rights, please contact [email protected] or Out Licensing, Life Technologies, 5791 Van Allen Way, Carlsbad, California 92008.

© 2011 Life Technologies Corporation. All rights reserved. The trademarks mentioned herein are the property of Life Technologies Corporation or their respective owners. Printed in the USA. CO31442 0411

Ordering information

Description Quantity Part number

Attune® Acoustic Focusing Cytometer (includes computer, monitor, startup solutions, installation, and warranty) 1 4445315

Attune® Focusing Fluids, 1X solution, 1 L 1 4449790

Attune® Focusing Fluids, 10X solution, 1 L 1 4449792

Attune® Focusing Fluids, 1X solution, 6 x 1 L 1 4449791

Attune® Wash Solution 1 4449755

Attune® 10X Shutdown Solution 1 4454955

References

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