SpectraMax i3x Multi-Mode Detection Platform

Explore a wealth of applications in one future-ready system.

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The SpectraMax® i3x Platform from Molecular Devices is a multi-mode microplate reader system that evolves with your future needs and offers an unlimited breadth of application possibilities.

Future ready
The SpectraMax i3x Multi-Mode microplate reader measures spectral-based Absorbance, Fluorescence, and Luminescence with the added functionality of modular upgrades for Western Blot, Imaging, and Fast Kinetics with Injectors. The SpectraMax i3x reader allows you to unravel the mysteries of science by exploring cellular pathways and protein activation and expression in one system.

Protect your initial investment — purchase a system with the flexibility to add novel detection capabilities without the need for service engineers or costly system downtime. The SpectraMax i3x reader grows with you as your research areas expand.

Be Future Ready with the SpectraMax i3x Multi-Mode Detection Platform.

SpectraMax i3x Quotation

SpectraMax i3x Brochure

SpectraMax i3x Application Note
Application Note

SpectraMax Injector Cartridge

Capture Flash-type assays with ease
The SpectraMax Injector Cartridge with SmartInject™ Technology for the SpectraMax® i3x Multi-Mode Microplate Detection Platform allows you to expand your research capabilities to include flash based applications, including dual luciferase and ATP assays.

Click here to learn more >>

Spectral Fusion™ Illumination

Expanded dynamic range 
Engineered for performance with Spectral Fusion™ illumination for increased sensitivity across the entire excitation range and a cooled photomultiplier tube (PMT) for improved detection in extremely low light. Generate more data points without the need to dilute.

SpectraMax I3x Reader

User-upgradeable applications 
User-exchangeable detection modules expand the system’s detection capabilities to include Time-Resolved Fluorescence, HTRF, Fast Kinetics with Injectors, and Western Blot detection. Future proof your discoveries and let the SpectraMax i3x reader evolve with your research.

SpectraMax® Minimax™ 300 Imaging Cytometer

One complete solution 
With available options such as the SpectraMax® MiniMax™ 300 Imaging Cytometer, ScanLater™ Western Blot cartridge, reagents optimized for high performance, and the industry-leading data acquisition and analysis tool SoftMax Pro, the SpectraMax i3x Detection Platform is the total solution for all your research needs. Let Molecular Devices® and the SpectraMax i3x Multi-Mode Detection Platform power your next landmark discovery.



Investigate every aspect of a cellular pathway 

Investigate Every Aspect ofCellular Pathway

From imaging of cell confluence and viability under different treatment conditions to quantitation of nucleic acids and protein to western blot analysis, a wealth of new knowledge is captured using a single instrument. One versatile software package powers data acquisition and analysis, from raw data to publishable results. See more and do more cellular to protein analysis using a single detection system.



Live cell imaging

Live Cell Imaging


The SpectraMax MiniMax 300 Imaging Cytometer option allows for live cell images and analysis (top, left). The ScanLater Western Blot Detection Cartridge enables protein detection (top, right).



Visualize cells with
your microplate reader

Visualize Cells with Microplate Reader


Imaging with the SpectraMax MiniMax 300 Imaging Cytometer mirrors the plate reading workflow on the SpectraMax i3x System. The plate is set up for reading and images are acquired according to specified parameters. Cells in each image are identified by SoftMax® Pro Software and cell-by-cell statistics are collected. Data are then analyzed and visualized in different graphical representations.


Technical specification of the SpectraMax i3x are identical to those of the SpectraMax i3

With the SpectraMax i3x Multi-Mode Detection Platform, researchers are able to use a wide range of detection cartridges, like the ScanLater Western Blot System, that provide increased plate reader functionality. The SpectraMax MiniMax 300 Imaging Cytometer option is available for cellular imaging assays and the SpectraDrop™ Micro Volume Microplates for low volume DNA, RNA and protein sample prep. Now, all of your needs are covered with a single plate reader.

Representative Applications

  • AlphaScreen®
  • Apoptosis
  • BRET
  • Cellular imaging assays
  • Cell cycle analysis
  • Cell proliferation, viability, cytotoxicity
  • Enzyme activity
  • Epigenetics
  • Fast kinetic calcium mobilization assays
  • Flash based applications including dual luciferase and ATP assays
  • Fluorescent protein expression
  • FRET
  • Genotyping
  • GPCRs
  • HTRF®
  • Immunoassays
  • Ion channels
  • Membrane potential assays
  • Micro Volume (Low volume) Applications
  • Molecular interactions
  • Nuclear receptor
  • Nucleic acid and Protein quantitation
  • Reporter assay
  • Time-Resolved Fluorescence (TRF)
  • Western blot detection




SpectraMax Injector Cartridge with SmartInject™ Technology


The SpectraMax Injector Cartridge for the SpectraMax® i3x Multi-Mode Microplate Detection Platform allows you to expand your research capabilities to include flash based applications, including dual luciferase and ATP assays.SpectraMax Injector Cartridge with SmartInject


  • Light tight compartment to reduce interference
  • Reverse Prime option for low dead volume down to 10 µL
  • Removable reagent tray for easy cleaning and sterilization
  • Drag-and-drop simplicity with Acquisition Plan Editor
  • Easy-to-use touchscreen for priming, washing, and rinsing
  • SmartInject Technology ensures rapid signal development
  • Bubble Detection maintains assay injection accuracy
  • Overflow Protection prevents spillage within the instrument


Scan Later Western Blot Detection System 

Scan Later Western Blot Detection System


The ScanLater Western Blot Detection Cartridge is a user-installable option for the SpectraMax i3x and Paradigm® Multi-Mode Platforms. The ScanLater Western blot system simplifies the traditional western blot protocol by employing a europium-labelled secondary antibody which is then read by Time-Resolved Fluorescence (TRF). This substrate free detection method enables membrane scanning up to 30 days after the final wash step. The assay demonstrates sensitivity in the high femtogram, comparable to traditional chemiluminescence western blot methods. Leveraging this novel technology, researchers can:

  • Add western blot detection to their microplate reader within two minutes
  • Eliminate time-dependent substrate addition steps
  • Use one software platform, SoftMax® Pro Software to integrate both microplate and western blot detection assays


  • User-installable cartridge for the SpectraMax i3x and Paradigm Multi-Mode Platforms
  • TRF detection using Europium-labelled secondary antibody reduces background while increasing dynamic range.
  • Digital photon counting provides TRF counts unaltered for a high level of data integrity
  • Europium resists photo bleaching and is stable for weeks, enabling re-use of blots
  • Compatible with goat anti-rabbit, anti-mouse, Goat Anti Mouse, Goat Anti Rabbit, streptavidin, Donkey Anti Goat, Donkey Anti rat or streptavidin labeled antibodies
  • SoftMax Pro acquisition and analysis software that provides built-in protocols for Western Blot reads and easy-to-use image analysis and accurate quantification tools


SpectraMax MiniMax 300 Imaging Cytometer

SpectraMax MiniMax 300 Imaging Cytometer


The SpectraMax MiniMax 300 Imaging Cytometer option, which is field-upgradeable for any SpectraMax i3x base system, provides researchers with cellular analysis capability without the need to invest in complex imaging systems.


  • Obtain cell-based data in addition to well-based intensity readings in the same instrument
  • Eliminate cell staining for cell counting and confluency with StainFree Technology
  • Perform multi-parametric assays and get rich, cell-by-cell statistics
  • Easily measure low cell concentration samples


  • Brightfield and fluorescent green and red detection channels
  • Cytotoxicity, protein expression and cell proliferation assays in addition to ratio-metric assays like live-dead and transfection efficiency
  • ANSI/SBS conformant plate compatibility
  • Quick cellular identification and segmentation with SoftMax® Pro Microplate Data Acquisition & Analysis Software


StainFree Cell Detection Technology

StainFree Cell Detection Technology


The patent-pending StainFree Cell Detection technology on the SpectraMax MiniMax 300 Imaging Cytometer allows users to perform cell proliferation, cytotoxicity, and other assays without nuclear stains like DAPI or live cell dyes that are toxic to cells in the long term. Using StainFree Cell Detection Technology, users can:

  • Count cells and estimate confluence without fluorescent dyes
  • Monitor cell growth without disrupting cells
  • Set-up imaging assays quickly and easily with SoftMax Pro Software




General Specifications

(W x H x D)
12.63 (H) x 15.38 (W) x 23.38 (D) (in)
42.23 (H) x 39.05 (W) x 59.37 (D) (cm)
Weight 68.3 lbs (31 kg)
Power consumption < 200 watts
Power source 100-240 VAC, 2 A, 50/60 Hz
Robotic-compatible Yes

General Photometric Performance

Plate formats 6 to 1536 wells*
Light source Spectral Fusion Illumination (Xenon flash lamp + high-powered LEDs or laser diode in detection cartridges)
Reading capabilities Microplates, cuvettes (via adapter), low volume samples (via SpectraDrop, Micro-Volume Microplates)
Detectors PMT and/or photodiode
Shaking Linear and orbital
Dual Auto Injectors 50 amol ATP (<=> 250 fM @ 0.2mL/well, “Flash” luminescence using Promega Enliten)
3 fmol ATP (<=> 15 pM @ 0.2mL/well, “Glow” luminescence using PerkinElmer ATPlite 1step)
Click here to learn more
Temperature control 4°C above ambient to 45°C
Temperature uniformity ± 0.75°C
Temperature accuracy ± 1°C at 37°C set point
Environmental control Gas quick connect
Endpoint reading all modes
Kinetic reading all modes
Spectral scanning Absorbance, Fluorescence, Luminescence
Well scanning Over 20 by 20 in all modes
Wavelength selection 1.0 nm increments

Standard Read Times (minutes:seconds)**

  96 wells 384 wells
Absorbance 0:30 1:40
Fluorescence Intensity 0:25 1:25
Luminescence 0:30 1:15

Absorbance Photometric Performance

Wavelength range 230-1000 nm
Wavelength bandwidth 4.0 nm
Wavelength accuracy ± 2.0 nm
Wavelength repeatability ± 1.0 nm
Photometric range 0-4.0 OD
Photometric resolution 0.001 OD
Photometric accuracy < ± 0.010 OD ± 1.0%, 0-2OD
Photometric precision < ± 0.003 OD ± 1.0%, 0-2 OD
Stray light < 0.05% @ 230 nm

Fluorescence Intensity Performance

Wavelength range 250-850 nm
Wavelength selection 1.0 nm increments
Bandwidth Adjustable: 9/15 nm (ex), 15/25 nm (em)
Dynamic range > 6 logs
Top sensitivity (fluorescein)
96 wells 0.5 pM
384 wells 1 pM
Bottom Sensitivity (Fluorescein)
96 wells 2.5 pM
384 wells 5 pM

Luminescence Performance

Wavelength range 300-850 nm
Wavelength selection Choice of simultaneous detection of all wavelengths or selection in 1.0 nm increments
Dynamic range > 6 decades
Cross-talk < 0.4% in white 96- and 384-well microplates
Sensitivity (ATP-Glow)
96 wells 3 pM
384 wells 6 pM

* 1536 detection available via detection cartridges.

** With 6 flashes in absorbance and 3 flashes in fluorescence mode, and 0.1 sec/well integration in 96-well luminescence mode and 0.04 sec/well integration in 384-well luminescence mode.

Related Videos

SpectraMax i3x Multi-Mode Microplate Reader System

Learn about the SpectraMax i3x Multi-Mode Plate Reader capabilities and options in this short video.


Related Collateral


Data Sheets



The resources listed below were created using the SpectraMax i3.  
Technical specifications for the SpectraMax i3x are similar to those of the SpectraMax i3.  For luminescence, the LLD specification for the SpectraMax i3x is 5x lower (better) than for the SpectraMax i3.



Related Webinars

Novel Ways to Monitor Cell Growth and Cytotoxicity: StainFree Technology

Novel Ways to Monitor Cell Growth and Cytotoxicity: StainFree Technology



  • Novel In Vitro Assay Tools for Cardiac Toxicity and Discovery



Visit @ the Cell Counter for our monthly features.

SpectraMax® i3x Multi-Mode Microplate Reader System

System Options

Product Part Number
SpectraMax i3x Multi-Mode Microplate Reader with SoftMax Pro Software i3x
SpectraMax MiniMax 300 Imaging Cytometer 5024062
SoftMax Pro 6.x GxP Software by license bundle
SpectraTest (ABS1) Absorbance Validation Plate 0200-6117
SpectraTest (LM1) Luminescence Validation Plate 0200-6186
SpectraTest (FL1) Fluorescence Validation Plate 0200-5060
SpectraDrop Micro-Volume Starter Kit 0200-6262
SpectraDrop Micro-Volume HTS Kit 0200-6267

SpectraMax Detection Cartridge Options

Product Name Part Number
AlphaScreen Detection Cartridge (384 STD) 0200-7017POS
AlphaScreen Detection Cartridge (384 HTS) 0200-7018POS
AlphaScreen Detection Cartridge (1536 HTS) 0200-7019POS
HTRF Detection Cartridge 0200-7011POS
TRF Detection Cartridges 0200-7008POS
Fluorescence Polarization Detection Cartridge
Fluorescence Polarization Detection Cartridge (Rhodamine) 0200-7010POS
Luminescence Detection Cartridge 
(Glow for 96-well plates)
Luminescence Detection Cartridge 
(Glow 96- and 384-well plates)
Luminescence Detection Cartridge  
(Glow 96-, 384-, and 1536-well plates)
Dual Glow Luminescence Detection Cartridge
Fluorescence Intensity Detection Cartridge 
Fluorescence Intensity Detection Cartridge 
Fluorescence Intensity Detection Cartridge
Fluorescence Intensity Detection Cartridge
Fluorescence Intensity Detection Cartridge
Fluorescence Intensity Detection Cartridge
ScanLater Western Blot Detection Cartridge 0200-7027
SpectraMax Injector Cartridge with SmartInject™ Technology 0200-0729

Number of Citations*: 344

Latest Citations:
For a complete list of citations, please click here.

Glutamine activates STAT3 to control cancer cell proliferation independently of glutamine metabolism

A Cacace, M Sboarina, T Vazeille, P Sonveaux - Oncogene, 2016 -
... (f) Cell proliferation measured using Ki-67 staining (**P<0.01, ***P<0.005; n=6). (g) Cell number
assessed using a SpectraMax i3 multi-mode microplate reader after treatment with the indicated
doses of glutamine (*P<0.05, ***P<0.005 compared with media +Q, ### P<0.005 ...

Functional Analysis of DUF1 in Saccharomyces cerevesiae

R Keuls, B Lozzi, P Anderson, F Les Erickson - The FASEB Journal, 2016 - FASEB
... understanding of the cellular activities of Duf1. Cell growth experiments were
performed in 96-well plates using a Spectramax i3 plate reader and cell number
was plotted against time. Growth rate and maximum cell number ...

[HTML] Rainbow Vectors for Broad-Range Bacterial Fluorescence Labeling

M BarbierFH Damron - PloS one, 2016 -
... Absorbance was measured at regular intervals using a Spectramax I3 fluorescence microplate
reader (Molecular Devices, Sunnyvale, CA). Optical densities were corrected for 1 cm path length. ...
Changes in absorbance and fluorescence were monitored using a Spectramax I3...

Antioxidant and antiproliferative activities in immature and mature wheat kernels

MJ KimSS Kim - Food chemistry, 2016 - Elsevier
... Fluorescence intensity was measured using a SpectraMax® i3 plate reader
(Molecular Devices, Sunnyvale, CA, USA) at an excitation wavelength of 485 nm
and an emission wavelength of 520 nm for 75 cycles. The raw data ...

Ethanol extract of baked Gardeniae Fructus exhibits in vitro and in vivo anti-metastatic and anti-angiogenic activities in malignant cancer cells: Role of suppression of …

M Im, A Kim, JY Ma - International Journal of Oncology, 2016 -
... plates (SPL, Kyounggi-do, Korea). After 1, 2 and 3 h, green fluorescence intensity
was measured in a SpectraMaxi3 microplate reader (Molecular Devices, Sunnyvale,
CA, USA) set at Ex/Em 490/525 nm. For uPA activity assays ...

Preparation and Characterization of Cysteine Adducts of Deoxynivalenol

A Stanic, S Uhlig, A Solhaug, F Rise… - Journal of agricultural …, 2016 - ACS Publications

Transcriptome association analysis identifies miR-375 as a major determinant of variable acetaminophen glucuronidation by human liver

I Papageorgiou, M Freytsis, MH Court - Biochemical Pharmacology, 2016 - Elsevier
... 48 h after transfection, cells were harvested and firefly and Renilla luciferase activities
were measured with a SpectraMax i3 microplate reader (Molecular Devices, Sunnyvale,
CA) using the Dual-Glo Luciferase Assay System (Promega). ...

Chaetominine reduces MRP1-mediated drug resistance via inhibiting PI3K/Akt/Nrf2 signaling pathway in K562/Adr human leukemia cells

J Yao, X Wei, Y Lu - Biochemical and biophysical research communications, 2016 - Elsevier
... Briefly, cells were seeded in 96-well plates and incubated with drugs for 48 h. 3-[4,
5-dimethylthiazol-2-yl]-2, 5-diphenyl-tetrazolium bromide (5 mg/mL; Sigma) was added to each
well and absorbance was measured on a microplate reader (SpectraMax ® i3, Wals, Austria) ...

How the Linker Connecting the two kringles influences activation and conformational plasticity of prothrombin

N Pozzi, Z Chen, E Di Cera - Journal of Biological Chemistry, 2016 - ASBMB
... The independent Michaelis-Menten parameters k cat and k cat /K m were obtained by nonlinear
fit of the experimental data collected in a SpectraMax i3x multimode detection platform using
the software Origin 2015 (OriginLab Corporation, Northampton, MA). ...

[HTML] Assessment of the Cytotoxic and Apoptotic Effects of Chaetominine in a Human Leukemia Cell Line

J Yao, R Jiao, C Liu, Y Zhang, W Yu… - Biomolecules & …, 2016 -
... drug. The IC 50 values were calculated with a microplate reader (SpectraMax ® i3,
Wals, Austria) at an experimental wavelength of 570 nm and a reference wavelength
of 630 nm. Evaluation of nuclear morphology. The nuclear ...

* as of December 6, 2016. Source: Google Scholar.  Search results include "SpectraMax i3" and "SpectraMax i3x".