SpectraMax Gemini XPS Microplate Reader

Create custom fluorescence assays

Develop new fluorescence assays without having to purchase expensive filter sets. The top-reading Gemini XPS Microplate Reader with dual monochromators lets you experiment with a variety of fluorophores and can even find the best excitation and emission wavelengths for your new assays. Multiple-point well scanning optimizes cell-based assay sensitivity.


  • Read a variety of sample formats from 6- to 384-well microplates in endpoint, kinetic, spectral scan, and well scan modes
  • Eliminate the need for identifying, purchasing, and changing out filters for wavelength optimization with dual monochromators for excitation and emission wavelength selection between 250 and 850 nm
  • Up to 4 wavelength pairs can be read for endpoint and kinetic measurements
  • Well scanning to report a fluorescent measurement from a single point in the center of a microplate well to multiple points across a tissue culture well

Measuring Accurately and Reproducibly

  • Avoid losing high signals to detector saturation and photobleaching after repeated reads to find the correct reader settings with AutoPMT System electronics
  • Compare relative fluorescence units (RFUs) between samples, like with no other fluorometer, allowed by a unique calibration against an internal standard
  • Monitoring of temperature-sensitive reactions with consistent temperature regulation from ambient to 45°C
  • Thorough mixing of samples in microplate wells by user-programmable Automix feature
  • Gentle movement of cell or other aggregates in the microplate with a slow carriage speed option
  • Seamless automation coupling with the StakMax Stacker, Molecular Devices' own integrated microplate stacker designed exclusively for the SpectraMax Reader

Comprehensive Reader Validation

Molecular Devices microplate readers have the most variety of tools available for users to meet their diverse hardware and software validation needs. Molecular Devices provides complete solutions with:


The Gemini XPS Microplate Reader supports a multitude of fluorescence assay categories including:

  • ELISAs and immunoassays
  • Nucleic acid (DNA) quantitation
  • Protein quantitation
  • Reporter gene assays
  • Cell viability, proliferation, and cytotoxicity
  • Enzyme assays
  • Transporter assays
  • Phosphotases/kinases
  • Microbial growth

SoftMax® Pro Software is the most published microplate reader control and microplate data analysis software package available to scientists. The inclusive package of ready-to-run protocols, analysis algorithms, and 21 different curve fit options provides the full solution from data acquisition to analysis to publishing. The FDA 21 CFR Part 11 compliance tools available in SoftMax Pro GxP Software for regulated laboratories deliver a complete solution to minimize validation costs, provide end-to-end chain of custody, and eliminate the need to validate additional analysis software.

General Specifications

Dimensions (in.) 8.6 H x 22.8 W x 15 D
Dimensions (cm) 22 H x 58 W x 38 D
Weight 35 lb (16 kg)
Power source 100-240 VAC, 50/60 Hz

Performance Specifications

Wavelength Range - Excitation 250-850 nm
Wavelength Range - Emission 360-850 nm
Wavelength Selection Monochromator, tunable 1.0 nm increments
Wavelength Bandwidth (Excitation and Emission) 9 nm
Wavelength Accuracy  < ± 2.0 nm
Top Read Sensitivity  3.0 fmol/well FITC 200 µl in 96 wells
Light Source Xenon flash lamp

Microplate Read Time

Normal Mode 96 wells 15 seconds
384 wells 45 seconds
Dynamic Range  6 orders of magnitude
Temperature Range  Ambient + 4 °C up to 45 °C
Temperature Uniformity (Microplate)  ± 1 °C @ 37 °C


Gemini™ XPS Microplate Reader



Product Number

Gemini XPS Microplate Reader XPS
SpectraTest FL1 Fluorescence Validation Plate 0200-5060
SpectraDrop™ Micro-Volume Microplate Starter Kit 0200-6262
SpectraDrop™ Micro-Volume HTS Kit 0200-6267
 StakMax Microplate Handling Stacker StakMax
Microplate Reader Shelf 9000-0756

Number of Citations*: 779

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

Increased Vulnerability to Physical Stress by Inactivation of NdgR in Streptomyces coelicolor

BR Lee, DH Yi, E Song, SK Bhatia, JH Lee… - Applied biochemistry …, 2015 - Springer
... Two hundred microliters of the samples was mixed with 1 μL of the 1:1 mixture of SYTO®
9 and PI and incubated for 15 min in dark. The released fluorescence was measured using
Gemini XPS fluorimeter (Molecular Devices, Sunnyvale, CA). ...

[PDF] The chemokine platelet factor-4 variant (PF-4var)/CXCL4L1 inhibits diabetes-induced blood-retinal barrier breakdown

A El-Asrar, M Ahmed, G Mohammad… - … & visual science, 2015 -
... Fluorescence was measured using a spectraMax Gemini-XPS microplate reader
(Molecular Devices, Sunnyvale, CA, USA) with excitation and emission wavelengths
of 485 nm and 538 nm, respectively, with PBS as a blank. ...

siRNA Delivery Impedes the Temporal Expression of Cytokine-Activated VCAM1 on Endothelial Cells

TT Ho, JO You, DT Auguste - Annals of Biomedical Engineering, 2015 - Springer
... of time were mixed with 100 µL of RNA detecting RiboGreen reagent (Life Technologies, Carlsbad,
CA, USA), incubated at RT for 5 min, then analyzed in 96-well plates using a fluorescence
microplate reader (SpectraMax Gemini XPSMolecular Devices Corp., Sunnyvale, CA ...

1‐[2‐(4‐Benzyloxyphenoxy) Ethyl] Imidazole inhibits monoamine oxidase B and protects against neuronal loss and behavioral impairment in rodent models of …

JY Chung, JW Lee, CH Ryu, HK Min… - Journal of …, 2015 - Wiley Online Library
... min. The fluorescence was measured by a fluorescence microplate reader (Gemini
XPS microplate reader; Molecular Devices, Sunnyvale, CA) with a filter set for
excitation and emission at 563 and 587 nm, respectively. The ...

Protein Adsorption on a Laser-Modified Titanium Implant Surface

S Cei, D Karapetsa, E Aleo, F Graziani - Implant dentistry, 2015 -
... Considering that the fluorescence intensity is proportionally related to the amount of protein
adsorbed on the surface, the fluorescence of each treated disc was quantified using a microplate
spectrofluorometer (Spectramax Gemini XPSMolecular Devices, Silicon Valley, CA) set ...

Lavandula stoechas essential oil from Spain: Aromatic profile determined by gas chromatography–mass spectrometry, antioxidant and lipoxygenase inhibitory …

A Carrasco, V Ortiz-Ruiz, R Martinez-Gutierrez… - Industrial Crops and …, 2015 - Elsevier
Lavandula stoechas essential oils (EOs), obtained from plants grown in the South East of Spain,
were analyzed by gas chromatography coupled with mass spectromet.

Pinacidil protects osteoblastic cells against antimycin A-induced oxidative damage

EM Choi, WW Jung, KS Suh - Molecular medicine …, 2015 -
... ester (AM) for 1 h at 37°C. Following washing with PBS, fluorescence emission (510 nm) was
monitored at the excitation wavelengths of 340 and 380 nm using a Gemini XPS microplate reader
(Molecular Devices, LLC) according to the manufacturer's instructions. ...

Epoxy-α-Lapachone Has In Vitro and In Vivo Anti-Leishmania (Leishmania) amazonensis Effects and Inhibits Serine Proteinase Activity in This Parasite

F Souza-Silva, SC Bourguignon… - Antimicrobial agents …, 2015 - Am Soc Microbiol
... Samples were incubated for 60 min at 37°C, and the variance in the relative fluorescence units
(RFU), corresponding to enzymatic cleavage of the substrates, was monitored with a Molecular
Devices SpectraMax spectrophotometer (Gemini XPS) (7). Concomitantly, the efficacy ...

Inactivation of polyphenol oxidase using 254 nm ultraviolet light in a model system

L Haddouche, A Phalak, RV Tikekar - LWT-Food Science and Technology, 2015 - Elsevier
... However, due to the limitations of the equipment (Gemini XPS fluorescence micro-plate reader,
Molecular Devices, Sunnyvale, CA), enzyme solutions were excited at 280 nm, and the
fluorescence spectra were scanned in a wavelength range of 360–500 nm. ...

Sonocatalytic injury of cancer cells attached on the surface of a nickel–titanium dioxide alloy plate

K Ninomiya, H Maruyama, C Ogino, K Takahashi… - Ultrasonics …, 2015 - Elsevier
... Fluorescence signals of 2HTA following the reaction of TA with OH radicals were measured using
a microplate spectrofluorometer (Gemini XPSMolecular Devices, Sunnyvale, CA, USA) at
excitation and emission wavelengths of 315 nm and 425 nm, respectively. ...


* as of June 26, 2015. Source: Google Scholar.