Description

Biofargo Fluorometric Protein Quantification Kit measures protein concentration in solution using a fluorogenic dye. The dye gives little signal on its own and becomes strongly fluorescent once bound to protein, so the fluorescence read after a short incubation is proportional to the amount of protein in the sample.

Fluorescence detection reaches lower protein concentrations than absorbance-based methods such as BCA and Bradford, so a smaller volume of a precious sample is used up per measurement. The assay is run as a mix-and-read procedure: sample and working reagent are combined, incubated 15 minutes at room temperature, and read directly, with no separation or wash steps.

The kit is supplied in two sizes. The 100-reaction size (BF52041001) suits method set-up and small sample sets; the 1,000-reaction size (BF52041002) suits routine and higher-throughput quantification. Both sizes use the same reagent formulation, so results are comparable between them.

Specifications

Parameter	Specification
Product Name	Fluorometric Protein Quantification Kit
Catalog Numbers	BF52041001 (100 reactions) / BF52041002 (1,000 reactions)
Assay Principle	Fluorogenic dye binding; fluorescence proportional to protein concentration
Detection	Fluorescence
Excitation / Emission	470 / 570 nm (read with 485 / 590 nm filters)
Assay Range	0.25–5 µg protein per reaction; pseudolinear response 0.5–4 µg
Sample Concentration Range	12.5 µg/mL – 5 mg/mL before dilution
Sample Volume	1–20 µL per reaction; final assay volume 200 µL
Working Solution	Reagent diluted 1:200 in the supplied buffer, prepared fresh
Incubation	15 minutes at room temperature; signal stable for up to 3 hours
Compatible Instruments	Biofargo Fluorometer X1 and X3 (Protein program); Qubit™ fluorometers running the Protein assay; fluorescence microplate readers with 485 / 590 nm filters
Protein Standard	Bovine serum albumin (BSA) standards included for the calibration curve
Interference Tolerance	Tolerates 1 mM DTT and 1 mM β-mercaptoethanol. Detergents (SDS, Tween™ 20, Triton™ X-100) are not recommended
Pack Sizes	100 reactions; 1,000 reactions
Storage	Reagent at room temperature, desiccated and protected from light; buffer and standards at 2–8 °C
Shelf Life	At least 6 months from receipt when stored as directed
Intended Use	For research use only

Features

Fluorescence detection reaches lower protein concentrations than colorimetric BCA or Bradford assays, so less sample is consumed per measurement.
Mix-and-read format — combine sample and working reagent, incubate 15 minutes, and read; no separation, wash or stop steps.
1–20 µL of sample per reaction, so dilute lysates and small eluate volumes can be measured directly.
Two pack sizes — 100 reactions for method set-up and small studies, 1,000 reactions for routine and higher-throughput work.
Same formulation across both sizes, so a method developed on the small kit transfers directly to the large kit.
Runs on Biofargo Fluorometer X1 and Biofargo Fluorometer X3 as well as on Qubit™ fluorometers and fluorescence microplate readers.
Standard-curve quantification — samples are read against a calibration curve run alongside them, so each run carries its own calibration rather than a stored factor.

Applications

Sample normalization: Equalize protein loading across lysates before SDS-PAGE, Western blot or ELISA.
Protein purification: Track protein in column fractions during chromatography and concentration steps.
Purified protein and antibody QC: Confirm the concentration of recombinant proteins and antibody preparations.
Enzyme and reporter assays: Express activity per milligram of total protein.
Proteomics sample prep: Check protein input before digestion and mass spectrometry.
Low-abundance samples: Quantify dilute lysates, eluates and conditioned media where colorimetric assays lack sensitivity.

Storage & Shipping

Ship at ambient temperature.
Store the fluorescent reagent at room temperature, desiccated and protected from light.
Store the assay buffer and the BSA standards at 2–8 °C.
Shelf life is at least 6 months from receipt when stored as directed.
Protect the fluorogenic reagent from light; keep vials closed when not in use.

Protocol Overview

Prepare working solution by diluting the fluorescent reagent 1:200 in the supplied assay buffer. Prepare enough for all samples and standards, and prepare it fresh on the day of use.
Set up the standards: add 10 µL of each BSA standard to 190 µL of working solution.
Set up the samples: add 1–20 µL of sample and bring the volume to 200 µL with working solution. Choose the input volume so the protein mass falls within 0.25–5 µg.
Mix by vortexing 2–3 seconds, avoiding bubbles.
Incubate 15 minutes at room temperature, protected from light.
Read on the Protein program of the fluorometer, or at 485 / 590 nm on a microplate reader. Read standards first to build the calibration curve, then read the samples.
Calculate the original sample concentration from the reading and the sample volume used. Dilute and re-measure any sample that reads above the top standard.

Frequently Asked Questions (FAQs)

Common questions about Fluorometric Protein Quantification Kit.

How is this different from a BCA or Bradford assay?

BCA and Bradford assays measure absorbance, while this kit measures fluorescence. Fluorescence detection reaches lower protein concentrations, so smaller sample volumes can be used. BCA and Bradford remain useful where a plate reader without fluorescence optics is the only instrument available.

What instrument do I need to run the assay?

The assay runs on Biofargo Fluorometer X1 and Biofargo Fluorometer X3 using the Protein program, on Qubit™ fluorometers running the Protein assay, and on fluorescence microplate readers fitted with 485 / 590 nm filters. Compatibility with Qubit™ instruments does not imply Thermo Fisher endorsement or identical performance. If you are unsure about your reader, contact us at contact@biofargo.com and we will confirm before you order.

What is the assay range?

Each reaction measures 0.25–5 µg of protein, with a pseudolinear response between 0.5 and 4 µg. That corresponds to an initial sample concentration of roughly 12.5 µg/mL to 5 mg/mL, depending on how much sample you add. Protein mass equals the initial concentration multiplied by the sample volume; dilute samples that read above the top standard.

How much sample is required?

Add 1–20 µL of sample and bring the reaction to a final volume of 200 µL with working solution. Choose the input volume so the protein mass lies within the assay range.

Which pack size should I choose?

The 100-reaction kit suits method set-up, occasional use and small sample sets. The 1,000-reaction kit lowers the cost per reaction and suits routine quantification or screening. Both use the same reagent formulation.

Is a protein standard included?

Yes. Bovine serum albumin (BSA) standards are supplied for the calibration curve. Run the standards alongside your samples in every batch rather than relying on a stored curve.

Does the assay tolerate detergents and reducing agents in my buffer?

Reducing agents are tolerated at 1 mM DTT and 1 mM β-mercaptoethanol. Detergents such as SDS, Tween™ 20 and Triton™ X-100 are not recommended and will bias the reading. If your lysis buffer contains detergent, dilute the sample so the detergent is well below its working concentration, or tell us which buffer you use at contact@biofargo.com and we will confirm whether the assay is compatible.

Can I use it with a 96-well plate?

Yes. The 200 µL assay volume suits a 96-well microplate on a fluorescence reader with 485 / 590 nm filters. Use black plates to limit well-to-well crosstalk and background.

Do you offer bulk or distributor pricing?

Yes. Bulk and distributor pricing is quoted on request. Contact us at contact@biofargo.com with the quantity you need.

Can it be used for clinical or diagnostic purposes?

No. This product is for research use only and is not intended for human, diagnostic or therapeutic use.

Compatible Instruments

This kit is run on the Biofargo fluorometers below.

Biofargo Fluorometer X1 — Single sample position. Select the Protein program on the instrument.
Biofargo Fluorometer X3 — Eight sample positions. Select the Protein program on the instrument.
Biofargo Fluorometer S96 — 96-well plate, full plate in 55 seconds. Select the Protein program on the instrument.

Documents

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