Pro-Quant Cuve
Pro-Quant Strip

Pro-Quant TM for Total Protein Quantification

Pro-Quant TM Total Protein eliminates chemical labeling reaction and keeps your precious sample intact

Plexense’s protein quantification method is very simple and straightforward:

  1. Place the protein sample into a Pro-Quant TM
  2. Read protein quantity with any available spectrophotometers


  • Easy to use
  • Preserve your sample intact
  • Short assay time: 15 minutes in some cases
  • Universal buffer compatibility
  • No costly equipment required
  • Compatible with conventional spectrophotometers
Pro-Quant Cuve Cortisol
Pro-Quant Strip Cortisol

Pro-Quant TM for Small Molecule Detection

Pro-Quant TM Cortisol – nano-coating technology enables detection of small molecules at rate much quicker than traditional assay

Small molecule detection in 30 minutes, only two mixing steps required.


  • Easy to perform, minimum expertise required
  • Short assay time: 30 minutes
  • Compatible with most conventional spectrophotometers

Nanoparticle Coating Technology

Sub-ug/ml sensitivity with a less than 10% in the production cost

Our sensors are produced based on Plexense’s proprietary nanoparticle coating technology, which enables conversion of low cost plastic consumables into highly sensitive nano-plasmonic biosensors monitoring various biological interactions between antibody-antigen, DNA-DNA, protein-protein, and small molecules in real-time. The sensors are used by simply placing sensors into a conventional visible absorption spectrophotometer or micro plate reader followed by measuring optical absorption value changes without requirement of additional dedicated analyzers.

Scanning Electron Microscope Image of the Sensor Surface

LSPR Principle Overview

Metallic nanoparticles present various colors from red to blue depending on their sizes and materials. The vast wine color of gold nanoparticles has been recognized for centuries in stained glass windows of medieval churches due to its unique color and chemical inertness over time.

Spectroscopic characteristics of metallic nanoparticles has been recently studied that such changes in absorption wavelength and optical absorption value are linearly corresponding to local environmental changes of metallic nanoparticles at nanoscale proximity.

Local changes near metallic nanoparticles are correlated with the surface coverage of analytes, that are for the most part due to local refractive index value changes disturbing spectroscopic interaction (localized surface plasmon resonance phenomena) between light and free electrons on a metallic nanoparticle surface. As a result, the amount of analytes absorbed on the nanoparticle surface causes a linear increase in the optical absorbance value. Quantitative measurement of analytes depending on absorption of molecules including small molecules, proteins and DNAs is performed by measuring spectroscopic changes, optical absorbance value, from Pro-Quant TM with conventional spectrophotometers without laborious use of labeling reagents.

Schematic view of the principle of protein detection using Pro Quant

Protein Detection Using Pro Quant

Spectra of Pro Quant before and after protein binding