A miniaturized optical immunosensor based on White Light Reflectance Spectroscopy (WLRS) for the rapid and label-free detection of aflatoxin M1 (AFM1) in milk samples has been developed. WLRS sensing system consists of the measurement set-up and the biochip. The first encompasses the reflection probe, the light source, and the spectrometer, while the latter is a Si chip with a SiO2 layer on top where an AFM1-bovine serum albumin conjugate has been immobilized. The assay was performed by running mixtures of rabbit polyclonal anti-AFM1 antibody with the calibrators or the samples, followed by reaction with biotinylated anti-rabbit IgG antibody and streptavidin. The assay cycle was completed in 25 min, the limit of detection was 6 pg/mL, and the linear working range extended from 0.012 to 2.0 ng/mL. The assay was repeatable (intra-and inter-assay coefficients of variation ranged from 2.1 to 6.3% and 3.5 to 8.2%, respectively) and accurate (percent recovery values ranged from 92.5 to 110%). AFM1 could be detected with the immunosensor developed in both processed and unprocessed milk of different animal species without any dilution. The excellent analytical characteristics and the small instrument size make the proposed sensor suitable for accurate low-cost AFM1 determination in milk samples at the point-of-need.
|D.Tsounidi, G. Koukouvinos, P. Petrou, K. Misiakos, G. Zisis, D. Goustouridis, I. Raptis, S. E. Kakabakos Sens. Act. B 282 104(2019) “Rapid and sensitive label-free determination of aflatoxin M1 levels in milk through a White Light Reflectance Spectroscopy immunosensor”|
A new product, FR-uProbe is released. FR-uProbe is a module for reflectance & trasnmittance measurements through any trinocular optical microscope with C-mount.
FR-uProbe is the solution for coating characterization applications that require spot size as small as very few micrometers, such as micropatterned surfaces, samples with irregular surfaces that exhibit a high level of scattering light and numerous others.
With FR-uProbe, local film thickness, optical constants, reflectance, transmission, and absorbance measurements across UV/Vis/NIR, is just a matter of a click.
The standard spot size (area from which the reflectactance or transmittance signal is collected) for 50X objective lens is 5μm and can be as small as 2μm.
|We are excited to announce that we are moving to a new location on April 1st. The move was driven by a requirement for more space in all departments, that will enable us to manufacture efficiently a larger quantity of products, and accommodate larger machines to support our growing client base.
Our new address is
Christou Lada 40
12132 Athens, Greece
Please use this address for your shipments.
Our telephone numbers (+30-213-0373544, +30-2130373547) remain the same.
|The fast and accurate determination of C-reactive protein (CRP) in human whole blood samples employing a WLRS sensing platform is demonstrated. Each assay cycle was completed in 12 min, including 5-min reaction with the diluted whole blood samples, 3-min with the biotinylated anti-CRP antibody, and 4-min with streptavidin solution. The effect of whole blood on the assay performance was evaluated, and it was found that dilutions as low as 50-times could be employed. Thus, taking into account that the assay had a detection limit of 2.2 ug/L CRP in 50-times diluted sample, whole blood concentrations as low as 110 ug/L could be determined. The excellent analytical characteristics, the short analysis time and the compact instrument size support the applicability of the immunosensor developed for point-of-care CRP determinations.|
|G.Koukouvinos, D.Goustouridis, K.Misiakos, S.Kakabakos, I.Raptis, P.Petrou Sens. Act. B 260 282(2018) “Rapid C-reactive protein determination in whole blood with a White Light Reflectance Spectroscopy label-free immunosensor for Point-of-Care applications”|
ThetaMetrisis is currently searching for a motivated Junior Engineer (with degree in Physics, Material Science or related discipline)
for work in the Quality control and Research & Development departments.
More information regarding the available position can be found in the following link:
|A fast label-free biosensor based on WLRS for the determination of PSA as semen indicator in forensic samples is developed. The sensor is based on a two-step immunoassay which employs the same polyclonal anti-PSA antibody as capture and detection antibody followed by reaction with streptavidin as a signal enhancement step. Following this protocol, a detection limit of 0.5 ng/mL was achieved and the assay's linear response range extended up to 500 ng/mL. Thus, taking into account the quantification limit of 1.0 ng/mL and the average PSA concentration in semen (0.2–5.5 mg/mL), semen quantities of a few nanoliters could be detected. A linear correlation was found for semen dilutions ranging from 5000 to 360,000. The lack of interference by other bodily fluids was confirmed by analysing stains of blood, urine and saliva prior to and after the addition of semen. Finally, the sensor was evaluated by analysing 51 forensic casework samples which were also analysed with a semi-quantitative membrane strip test (Seratec® PSA), through microscopic detection of spermatozoa, and male DNA identification through detection of Y chromosome. The results obtained with the sensor were in excellent agreement with those provided by an immunoradiometric assay kit (PSA-RIACT) and in complete agreement with the findings using the membrane strip assay, spermatozoa and Y chromosome detection. The excellent analytical performance and small size of the instrument make the sensor developed an attractive tool for use in forensic evidence screening for semen detection.|
|G.Koukouvinos, A.Metheniti, Ch.-E.Karachaliou, D.Goustouridis, E.Livaniou, K.Misiakos, I.Raptis, A.Kondili, P.Miniati, P.Petrou, S.Kakabakos Talanta 175 443(2017) “White light reflectance spectroscopy biosensing system for fast quantitative prostate specific antigen determination in forensic samples”|
Mycro Technologies Ltd and ThetaMetrisis has signed an agreement for the distribution of ThetaMetrisis products in the market of China. Prospective customers from China are kindly requested to contact Ms. Monica Mo or Mr. Aaron Deng for further information on ThetaMetrisis products and demonstration of their capabilities.
|A methodology for the simultaneous determination of pesticides chlorpyrifos, imazalil and thiabendazole in drinking water and wine samples with a biosensor based on White Light Reflectance Spectroscopy was developed. The whole analysis is completed in|
|G.Koukouvinos, P.S.Petrou, D.Tsounidi, Z.Τsialla, K.Misiakos, D.Goustouridis, A.U.Moreno, A.R Fernandez-Alba, I.Raptis, S.E.Kakabakos Sens. Act. B 238 1214(2017) “Fast and simultaneous detection of three pesticides by a White Light Reflectance Spectroscopy sensing platform”|