A S S AY P L AT E S

L I F E S C I E N C E S – C H O O S I N G T H E C O R R E C T A S S AY P L AT E

An introduction to clear bottomed assay microplates
Porvair Krystal series clear bottom plates are now recognised

We supply our Krystal clear plates treated for cell culture

as industry-leading tools for Pharma drug discovery andwith a low pressure gas plasma that produces an evenscreening. Our standard clear polystyrene bottom plates

surface treatment right across the plate. It is particularly

have bases just 0.4mm thick and are moulded from highly

suited to cell lines which do not grow easily on plastics. Ourpolished tools to reduce flow lines, artefacts and scratches,

plastic-bottomed plates are ultrasonically welded together –guaranteeing good results with all types of bottom-readinga tried and tested method which both guarantees a perfect

instruments. For the more modern demanding confocal

seal every time and eliminates the inconsistencies seen withreaders, Porvair Glass Bottom plates have been shown bylaser membrane welding used by other manufacturers. Only

leading research institutes to be unsurpassed for flatness,

biocompatible adhesives are used for glass bottom plates,

linearity and optical clarity. Our sparkling pure borosilicate

cured by UV radiation to ensure that the finished plates areglass is just 175µm thick with a flatness tolerance across thesolvent-free, have very low autofluorescence and will allow

plate of +/- 15µm ensuring superb crisp images every time.

good cell growth.

Choosing the correct assay plate
Absorbance assays –Top Reading Instruments

Bottom Reading Instruments

High signal from majority of wells e.g. test kits, ELISA
Use a simple solid clear plate

Normal visualisation: White plates with clear plastic
bottoms

Low signal from some or all wells e.g. kinetics orgenetic marker assays
Use a solid white plate to boost the signal

Confocal visualisation: White plates with glass bottoms
For very sensitive assays - Zero Crosstalk white platewith individual clear wells

Fluorescence assays –Top Reading Instruments

Bottom Reading Instruments

Use a solid black plate

Visible wavelength range 350-700nm
High signal from majority of wells e.g. GFP, Reporter
Gene kits,
Use a black clear-bottomed plate
Low signal from some or all wells e.g. poor sensitivity
assays, low specificity
Use a black Zero Crosstalk clear bottom plate to boost
the signal-to-noise ratio
UV Wavelength range 220-350nm
Use black clear-bottomed COP plates
Confocal or whole plate imaging:Use black glass-bottomed plates

Luminescence assays –Top reading instruments

Bottom Reading Instruments

Bio- and Chemi- Luminescence use the same plates
Good signal
Use solid white plates

Use a white clear-bottomed plate

Poor signal or high dynamic range across the plate
Use solid Black with White wells

2

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L I F E S C I E N C E S – C H O O S I N G T H E C O R R E C T A S S AY P L AT E

Choosing the correct assay plate
Choosing the correct microplate for your application can mean the
difference between indifferent and great results.
There are three basic methods of obtaining useful optical data frommicroplate-based samples. The simplest method is absorbancemeasurement. Where greater sensitivity is required, fluorescencemeasurements are preferred. Sensitivity can be ten times greaterthan simple absorbance measurements. The third method
involves luminescence, a naturally occurring phenomenon
exhibited by certain animal and plant species which can emit light.
This is a biological adaptation of a process which can also be seen as
purely chemically-driven reactions, in which case it is referred to as
chemiluminescence.
Microplate readers are designed to read from either the top or thebottom of a microplate. Top reading instruments rely on
measuring reflected light above the wells. A good solid brightwhite plate is best for these absorbance measurements and asolid black plate for fluorescence readings. Bottom reading units
illuminate the sample from above and then use detectors placed
below the plate to measure the absorption or
fluorescence/luminescence emission. This necessitates the use ofclear-bottomed plates. The requirement is to transmit the lightwavelengths of interest.
Visible wavelength range (900-350nm) measurements require
only clear plastic bases, whilst readings between 220nm and
350nm will require a UV-transparent material. This can be
Quartz sheet or a modern polymer such as Cyclo-Olefin CoPolymer (COP/COC). Optical glass sheet is used where visible range
detection is combined with confocal optics or whole plate imaging
which requires a very clear uniformly-flat base.
Simple 96-well microplates for ELISA type assays are made fromsolid clear polystyrene with no additives. These are adequate forclinical and diagnostic tests, ELISA assays and any colour endpoint determination with relatively high absorbance.Typicallythey are available with flat well bottoms, giving high surface area,
round well bottoms for good mixing or V-wells for high liquid
recovery.
Crosstalk can also be an issue in bottom-reading absorbance andfluorescence measurements. To address this applications
challenge, Porvair Sciences has developed the Krystal 2000
zero-crosstalk plates in which individual clear wells aremoulded into either a white or black matrix. The black or whitebase material also projects down below the clear well bottom tofurther reduce the possibility of crosstalk.
By carefully selecting the correct plate type for the assay, it is possible
to significantly improve results. By following the simple guidelines
set out here, those tasked with assay development can ensurethat their final assay has the best possible chance of success.
The table summarizes the choices available for Assay Plate
selection and indicates the plate type most likely to give the best
results. Porvair Sciences will be happy to supply samples of theirplates for evaluation free of charge, as different detection systems
and differing assay development may lead to variances in results
between ostensibly similar plate types.

W W W. M I C R O P L A T E S . C O M

3L I F E S C I E N C E S – S O L I D B O T T O M A S S AY P L AT E S

96-well clear plates
For routine adsorption, absorption, ELISA,
mixing and storage applications the standard
range of 96-well assay plates offers theperfect mix of affordability and high quality.

l Manufactured from high quality

crystal polystyrenel Flat bottom for spectrophotometricwork
l V-bottom minimizing residual liquidl Round (U) bottom forcell/particulate collectionl Robot compatiblel Working volumes from 275µl down

to 10µl

Solid assay plates
Plate description

4

SterileColourQty/pack

Cat. no.

96 wells of 350µl with a flat bottom

–

Clear

100

20800496 wells of 270µl with a round bottom

–

Clear

100

20900496 wells of 220µl with a V bottom

–

Clear

100

210004

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L I F E S C I E N C E S – S O L I D B O T T O M A S S AY P L AT E S

96-well black, white &black with white wells

l Black plates designed for top reading fluorescence

instrumentsl Black plates have low background fluorescence andPorvair Sciences range of solid bottom 96well assay plates is specifically designed forabsorbance, fluorescence, luminescence andscintillation applications. The design uses themost popular 96-well format with standard‘chimney’ wells to overcome optical crosstalkand contamination.

minimise light scatteringl White plates maximise signal for luminescencereadersl Highly polished well to give better readingsl Specially designed plate featuring a white well set ina black matrix to overcome the problem of a very
high luminescence causing false positives

These plates are designed to give optimum
results from any instrument which reads fromthe top of the plate.

l Working volumes of 350µl/welll Complies with the standard ANSI/SLAS format

The acclaimed composite black/white plate
has been shown to be ten times moresensitive than a standard white plate forchemi-luminesence assays.

l Alphanumerically labelled wells mean samples canbe easily traced

Solid polystyrene assay plates
Plate description

ColourTreatment

SterileLid

Qty/pack

Cat. no.

96 wells

White

–

–

–

100

204003

96 wellsWhite

Tissue culture

3

3

50

204512

96 wellsWhite

Tissue culture

3

3

100

204012

96 wells

Black

–

–

–

50

205503

96 wells

Black

–

–

–

100

205003

96 wells

Black

Tissue culture

3

3

50

205512

96 wells

Black

Tissue culture

3

3

100

205012

96 wells

Black with white wells

–

–

–

100

301004

W W W. M I C R O P L A T E S . C O M

5L I F E S C I E N C E S – S O L I D B O T T O M A S S AY P L AT E S

384 square-well platesl Designed to reduce well-to-well crosstalk

384-well assay plates from Porvair Sciences
are available in black, white and clear. These
have been optimised for fluorescence,luminescence/scintillation and ELISA/turbidity
measurements respectively. The working
volume is 120µl/well. All 384-well assay
plates are available in standard and tissue
culture treated formats.

l Black plates have low background fluorescence and

The 384-well format, with its higher densityof wells, allows more work to be carried out
in a standard sized plate, aiding higher
throughput. All of these plates are
manufactured from high quality polystyrene.

l Low residual volume

minimise light scatteringl White plates enhance bio- & chemi-luminescencesignals and have low background luminescence andfluorescencel Well working volumes of 100µl
l Rounded square at the well bottom to reduce

wickingl Designed to the standard ANSI/SLAS formatl Alphanumerically labelled wells mean samples canbe stored and easily traced

120µl/well

S Q U A R E

W E L L

Solid assay plates

6

Plate description

ColourTreatment

SterileLid

Qty/pack

Cat. no.

384 wells of 120µl

Clear

–

–

–

100

221003384 wells of 120µl

Clear

Tissue culture

3

3

50

221509384 wells of 120µl

Clear

Tissue culture

3

3

100

221009384 wells of 120µl

White

–

–

–

50

222503384 wells of 120µl

White

–

–

–

100

222003384 wells of 120µl

White

Tissue culture

3

3

50

222509384 wells of 120µl

White

Tissue culture

3

3

100

222009384 wells of 120µl

Black

–

–

–

50

223503384 wells of 120µl

Black

–

–

–

100

223003384 wells of 120µl

Black

Tissue culture

3

3

50

223509384 wells of 120µl

Black

Tissue culture

3

3

100

223009W W W. M I C R O P L A T E S . C O M

L I F E S C I E N C E S – S O L I D B O T T O M A S S AY P L AT E S

24-well Krystal™ black &white
Clear bottom plates allow the cells grown on
the bottom surface to be viewed using an
inverse microscope. In addition, light-emitting
assays can be measured from the bottom.
Porvair Sciences collection of clear bottom 24well Krystal plates are optimised for
fluorescence and luminescence. The special
design of the plate virtually eliminates wellto-well light crosstalk inherent with otherclear-bottomed microplate designs, enabling
unmatched accuracy, higher sensitivity andbetter repeatability of photometric readings.
For photometric applications where samples
are typically large, Porvair Sciences range of
unique black or white Krystal 24 plates
provides a perfect solution. Offering 24 highvolume (3.1ml) wells in the same convenient
footprint of a standard 96-well plate, theKrystal 24 provides a large surface area perwell, enabling efficient cell growth. All tissueculture treated plates are supplied lidded andsterile, in individual bags.

l Opaque walls to prevent well-to-well crosstalkl Clear plate bottom permits direct

microscopic viewingl Base plate thickness 0.75mm
l For use with top or bottom reading

instrumentsl Conforms to the standard

ANSI/SLAS format
l Well volume of 3.1ml
l Constructed with ultra-purepolystyrene components polished togive exceptional photometricperformance and optimised for cell
growthKrystal™ 24-wellColourTreatment

SterileLid

Qty/pack

Cat. no.

White

–

–

–

68

303002

White

Tissue culture

3

3

56

303006

Black

–

–

–

68

303008Black

Tissue culture

3

3

56

303012

W W W. M I C R O P L A T E S . C O M

7L I F E S C I E N C E S – C L E A R B O T T O M A S S AY P L AT E S

96-well Krystal™ black
and white
Porvair Sciences clear bottom 96-well Krystal
plates are optimised for fluorescence andluminescence. Proprietary ultra-sonic welding
is used to assemble the clear bases to the solid
top plate in our clean room. This design
provides flat, optically clear bases to each wellwith no leakage, enabling excellent accuracy
and reproducibility of photometric readings.
All tissue-culture treated plates are supplied
lidded and sterile, in individual bags.

l Opaque walls to prevent well-to-well crosstalkl Clear plate bottom permits direct

microscopic viewingl Thickness of bottom 0.75mm
l For use with top or bottom reading

instrumentsl Standard ANSI/SLAS format
l Well volume of 350µl
l Constructed from ultra pure grade

polystyrene

Krystal™ 96-well8

ColourTreatment

SterileLid

Qty/pack

Cat. no.

White

–

–

–

100

214003White

Tissue culture

3

3

100

214006

Black

–

–

–

100

215003Black

Tissue culture

3

3

100

215006

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L I F E S C I E N C E S – C L E A R B O T T O M A S S AY P L AT E S

384-well Krystal™ black
and white
The Krystal 384-well microplate range
incorporates novel square wells with a large
liquid capacity of 120µl per well, increasing
the achievable sensitivity of most HTS assays.
Using a proprietary manufacturing technique,the Krystal 384 offers market leading plate
flatness (+/- 0.1mm tolerance) that translates
into a significant increase in measurement
precision and elimination of read errors when
performing cell based assays using fluorescentor luminescent imaging. All tissue-culture
treated plates are supplied lidded and sterile,in individual bags.

l Opaque walls to prevent well-to-well crosstalkl Clear plate bottom permits direct

microscopic viewingl Thickness of bottom 0.40mm
l For use with top or bottom reading

instruments
l Maintaining the standard

ANSI/SLAS format
l Well volume of 120µl
l Constructed from ultra pure grade

polystyrene

Krystal™ 384-wellColourTreatment

SterileLid

Qty/pack

Cat. no.

White

–

–

–

100

311001

White

Tissue culture

3

3

100

311003

Black

–

–

–

100

312001Black

Tissue culture

3

3

100

312003

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9L I F E S C I E N C E S – C L E A R B O T T O M A S S AY P L AT E S

96-well Krystal™ 2000
black and whitel Raised rims to prevent well-to-well crosstalkl Lowered bottom rim to stop lateral light piping
l Clear well bottom permits direct microscopic

The unique Krystal 2000 plate range from
Porvair Sciences has been optimised forluminescence and fluorescence assays.
A patented manufacturing process, using a‘two-shot’ mould, provides clear, individual
wells in an opaque matrix. The special designof the plate totally eliminates the well-to-well
optical crosstalk inherent with other clearbottomed microplate designs, giving
unmatched accuracy, sensitivity andrepeatability of photometric readings. Veryhigh signal-to-noise ratio and low detection
limits can be achieved with this superb plate.
All tissue-culture treated plates are supplied
lidded and sterile, in individual bags.

viewingl For use with top or bottom reading instrumentsl Designed to the standard ANSI/SLAS format
l Total well volume of 350µl
l White matrix provides for maximum reflectivity,

allowing high sensitivity luminescence assaysl Black matrix provides a quenching of background

fluorescence, reducing false positives
l Constructed from ultra pure grade polystyrene

113.30
14.30
11.30

9.00

74.30

85.60

127.60
6.50
11.45

6.00

14.70

ALL DIMENSIONS IN MM

Cross-section of well

Clear cupColoured matrix

Krystal™ 2000 96-wellColourTreatment

SterileLid

Qty/pack

Cat. no.

White

–

–

–

100

301010White

Tissue culture

3

3

50

301512

White

Tissue culture

3

3

100

301012

Black

–

–

–

100

301002Black

Tissue culture

3

3

50

301506Black

Tissue culture

3

3

100

301006

10

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L I F E S C I E N C E S – C L E A R B O T T O M A S S AY P L AT E S

Krystal™ glass bottom
platesManufactured for whole-plate CCD imaging
and laser detection applications, Krystal glassbottom plates consist of a polystyrene upper
part and a clear borosilicate glass sheet fixed
to the base with a proprietary adhesive. This
process results in consistent flatness of thebase and gives improved light transmission
whilst maintaining a flat optical plane forgrowing cells. The nominal cut-off
wavelength of 335nm allows mostfluorescence assays to be excited or readthrough the glass bottom. All plates aresupplied lidded.

l 175µm glass thickness
l +/- 30µm flatness across basel 335nm UV optical cut-offl Industry-standard well layoutl Very low autofluorescencel High degree of planar flatness
l Biocompatible adhesivel Resistant to alcohol, DMSO and PBS
l Robot friendlyl Manufactured to ANSI/SLAS specification

Krystal™ 24-well glassbottom plates

Glass bottom assay plates
Number of wells

Description

SterileLid

Pack size

Cat. no.

24 wells

Black with lid, single pack

–

3

10

324041

24 wells

Black with lid, single pack

3

3

10

32404224 wells

White with lid, single pack

–

3

10

324051

24 wells

White with lid, single pack

3

3

10

324052

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11L I F E S C I E N C E S – G L A S S B O T T O M A S S AY P L AT E S

Krystal™ 96-well glassbottom plates

Glass bottom assay plates
Number of wells

Description

SterileLid

Pack size

Cat. no.

96 wells

Black with lid, single pack

–

3

10

324001

96 wells

Black with lid, single pack

3

3

10

324002

96 wells

White with lid, single pack

–

3

10

324011

96 wells

White with lid, single pack

3

3

10

324012

Description

SterileLid

Pack size

Cat. no.

384 wells

Black with lid, single pack

–

3

10

324021384 wells

Black with lid, single pack

3

3

10

324022384 wells

White with lid, single pack

–

3

10

324031384 wells

White with lid, single pack

3

3

10

324032

Krystal™ 384-well glassbottom plates

Glass bottom assay plates
Number of wells

12

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L I F E S C I E N C E S – G L A S S B O T T O M A S S AY P L AT E S

Krystal UV clear
bottomed microplates
Recently, scientists have begun using assay
chemistries which require excitation or
detection wavelengths in the far UV region,
below 350nm. To enable our customers todevelop assays in this area, Porvair Sciences
has introduced a very high specification rangeof COP-bottomed, UV-transparent
microplates. Precision engineered andassembled, these plates are available in 384well black matrix only for the most sensitive
UV range fluorescence assays using wholeplate imaging or confocal microscopy.

l 220nm far UV cut-offl Industry-standard well layoutl Very low autofluorescencel High degree of planar flatnessl High chemical resistance to most solventsl Robot friendlyl Cyclo Olefin Polymer construction with clear basel Precision engineered to meet ANSI/SLAS specification

Krystal UV COP-bottomed microplates
Description

Pack
size

Cat. no.

384-well Krystal
COP-bottomed plate32

327001

Detailed schematics available on request

Overall plate height = 14.35mm

W W W. M I C R O P L A T E S . C O M

13L I F E S C I E N C E S – U V C L E A R B O T T O M A S S AY P L AT E S

Porvair seals and foils
Porvair Sciences has a comprehensive rangeof seals and foils for thermal and adhesive
sealing of microplates. In addition, afull range of re-usable cap mats isavailable for friction sealing ofplates.
Foils and seals for
the MicroSeal
and MiniSeal Plusare supplied as cut
sheets, 125mm x78mm, in packs of
100.

229016229494

Porvair colour-coded thermal seals
Description

Qty/pack

Cat. no.

Easily pierced 20µm PP/PS lacquered aluminium foil – colour coded green
125mm x 78mm sheets printed with colour coding and right side up for ease of use

100229572

Peelable 70µm polyester/alumninium laminate sealing foil – colour coded red
125mm x 78mm sheets printed with colour coding and right side up for ease of use

100229571

Pierceable/peelable 38µm lacquered aluminium foil – colour coded blue
125mm x 78mm sheets printed with colour coding and right side up for ease of use

100229573

Strong 85µm thick aluminium foil for long term storage – colour coded black
125mm x 78mm sheets printed with colour coding and right side up for ease of use

100229574

Sealing film optically clear 75µm – non peelable, but pierceable
125mm x 78mm sheets printed with black coding and right side up for ease of use

100

500009Sealing film optically clear 105µm – peelable, but non pierceable
125mm x 78mm sheets printed with black coding and right side up for ease of use

100

500010

Qty/pack

Cat. no.

SealPlate® clear adhesive film for PP or PS plates

100

229016

ThermalSeal A® thermal cycler film for standard PCR

100229303

Adhesive seals (suitable for use down to -40ºC unless shown)
Description

ThermalSeal A® thermal cycler film for standard PCR, sterile

100229304

ThermalSeal RT2RR™ thermal cycler film for real-time PCR – 50µm films

100229521

AlumaSeal 96® aluminium seal for PCR and storage in 96-well plates with raised rims

100

229497

AlumaSeal CS™ aluminium seal for long term cold storage -80˚C

100229499Absorb Max™ optically-black film for light-sensitive assays

100

229520

EZ-Pierce™ easily pierceable polyethylene film

100

229306

Aeraseal™ gas-permeable, hydrophobic Rayon seal for cell culture, sterile (-20ºC only)

50

229308

X-pierce™ pre-scored film 96 Well Round – sterile

50229495

X-pierce™ pre-scored film 96 Well Round

100

229496Bright Max™ optically-white film for luminescent assays

100

WT-50

Qty/Pack

Cat. No.

EZ-Pierce™ sealing film 96-well round sterile

50229493

EZ-Pierce™ sealing film 96-well round50

229494

Zone-Free™ adhesive seals
Description

14

W W W. M I C R O P L A T E S . C O M

LIFE SCIENCES – THERMAL SEALSHeat seals and foils
Heat seals and foils
229574229573229572229571W W W. M I C R O P L A T E S . C O M

15

P/N 420003 © Porvair Sciences Limited 2017.
Produced by Cream Ink Limited www.creamink.com
Printed in the UK.

Customer Services and Sales Office
Porvair Sciences Ltd
Clywedog Road South
Wrexham Industrial Estate
Wrexham North WalesUK LL13 9XS
Tel: +44 (0) 1978 666240/666239
Fax: +44 (0) 1978 660007
email: int.sales@porvair-sciences.com
www.microplates.com

Accounts
Porvair plc
7 Regis Place
Bergen Way Kings Lynn
Norfolk UK PE30 2JW
Tel: 44 (0)1553 765500
Fax: +44 (0)1553 765599

Porvair Sciences offers a complete range of microplates for storage, collection, assays, ELISA and tissue
culture. For detailed information on our other products, including tissue culture plastics and ourrevolutionary Chromatrap® ChIP Assay kits, please request our other brochures or visit our website
www.microplates.com
Porvair Sciences catalogue of microplates& microplate equipment (70 pages)

C ATA LO G

CROPLUE OF MIICROPLAT E S & M

IPME
AT E E Q U

NT

ITION
SIXTH ED

Porvair Sciences chromatography
supplies catalogue (28 pages)

Porvair Sciences deep wellplates brochure (12 pages)
C H R O M ATO G R

APHY AND SAMPLE PREPARAT I O NC ATA LO G U E
FIRST EDITIONU LT R

A CL
EA

N PO
LY

PROP

YLEN

E STO
R

AGE

P L AT

ES C
ATA

LOGU

E