Larisa Poryvkina

• Ph.D.
• Managing Director at LDI Innovation

Commonly used biological indicators for assessing the efficiency of decontamination procedures include the spores of Bacillus atrophaeus (BA) and Geobacillus stearothermophilus (GS). BA and GS spores emit tryptophan-like fluorescence around 320 nm when excited by 280 nm UV light. This fluorescence signal is highly dependent on vaporised hydrogen pe...

This study is devoted to the development of a UV fluorimetry sensor capable of real-time monitoring of the decontamination process of microbiological pathogens by hydrogen peroxide vapour (HPV) treatment. The sensor is operating on the autofluorescence signal of tryptophan. The Bacillus atrophaeus (B. atrophaeus) and Geobacillus stearothermophilus...

A real-time detection and monitoring (RTDM) of microbial contamination on solid surfaces is mandatory in a range of security, safety and bio-medical applications where surfaces are exposed to accidental, natural or intentional microbial contamination. This work presents a new device, the BC-Sense, which allows a rapid and user-friendly RTDM of micr...

The accidental discharge or accumulated pollution in seawater constitutes high risk of damage to the marine environment. Early detection of deviations in water quality allows taking preventive measures in order to minimize harmful influence of pollution or to implement adequate response actions before the pollution becomes a major spill. This requi...

The high and still increasing number of attacks by hazardous bioorganic materials makes enormous demands on their detection. A very high detection sensitivity and differentiability are essential, as well as a rapid identification with low false alarm rates. One single technology can hardly achieve this. Point sensors can collect and identify materi...

In this work we propose novel technology for the on-line monitoring of animal by-product (ABP) rendering using a spectral fluorescence signature (SFS) analyzer integrated into the recirculation line of the extracted liquid. First, we investigated various methods that could be used for on-line monitoring and control of protein extraction processes a...

In current work the method of in vivo evaluation of apple juice degree of naturalness based on Spectral Fluorescence Signature (SFS) is proposed. SFS spectra of intact apple juice were measured as excitation-emission matrix by specially designed compact spectrofluorimeter with front-face optical layout - Instant Screener Compact (LDI AS, Estonia)....

The challenges of detecting hazardous biological materials are manifold: Such material has to be discriminated from other substances in various natural surroundings. The detection sensitivity should be extremely high. As living material may reproduce itself, already one single bacterium may represent a high risk. Of course, identification should be...

The research of bio-optical as well as hydrophysical properties of surface waters of the Nordic Seas have been for many years the subject of the polar experiments conducted by the Institute of Oceanology Polish Academy of Sciences. The spatial distribution and composition of organic matter molecules contained in a surface seawater layer is a conseq...

The invention is provided for detection of Heroin and Morphine in illicit drug samples, also for their differentiation. A liquid sample from a street sample is prepared and divided into two equal aliquots, one of them being reference sample, another being main sample. Both samples are treated with Hydrochloric acid and Sodium hydroxide, but those s...

The present invention relates to rendered product analysis and more particulary, to method for on-line control fat and protein compounds in meat and fish rendering systems using fluorescent detector. a relaible on-line system for express evaluation, usable for measuring of chemical content (protein, fat,moisture,ashes0 of organic materials during t...

In this paper, the validation procedure of spectral fluorescence signature (SFS) method combined with multilayer perceptron artificial neural networks (MLP‐ANNs) for detection of illegal drugs (cocaine, heroin and 3,4‐methylenedioxy‐N‐methylamphetamine) in street samples is proposed. The qualitative information, based on a binary response (detected...

For many years the Nordic Seas have been the subject of research into ocean circulation carried out by the Institute of Oceanology PAS, especially the inflow of Atlantic water and the intensive turbulent mixing of these waters with Arctic and shelf waters. Ocean currents affect various biological processes, among them the supply of organic matter a...

The NarTest fluorescent technique is aimed at the detection of analyte of interest in street samples by recognition of its specific spectral patterns in 3-dimentional Spectral Fluorescent Signatures (SFS) measured with NTX2000 analyzer without chromatographic or other separation of controlled substances from a mixture with cutting agents. The illic...

The airborne FLS-Lidars are based on the method of Laser Induced Fluorescence (LIF) and aimed at the analytical remote sensing of water objects. Scanning the laser beam across the flight trajectory and recording the comprehensive LIF spectrum with hyperspectral detector per every laser pulse provide detail maps of spectral properties of the water b...

The SFS technology has already proved its analytical capabilities in a variety of industrial and environmental tasks. Recently it has been introduced for forensic applications. The key features of the SFS method - measuring a 3-dimensional spectrum of fluorescence of the sample (intensity versus excitation and emission wavelengths) with following r...

The invention is provided for detection of Heroin and Morphine in illicit drug samples, also for their differentiation. A liquid sample from a street sample is prepared and divided into two equal aliquots, one of them being reference sample, another being main sample. Both samples are treated with Hydrochloric acid and Sodium hydroxide, but those s...

The invention is intended for illicit drug detection, preferably to Cocaine detection in street samples containing in addition to Cocaine also adulterants and/or diluents (also denominated as cutting agents) used for increasing the quantity of the product and/or for disguising the existence of Cocaine. The invention provides preparing of the liquid...

Invention handles the milk coagualtion time determination using the protein fluorescence detection in front-face mode measurements. Easy and rapid method is based on measurements of protein fluorescence intensity during the coagulation process. The observed in time maximum of fluorescence intensity (at fixed excitation/emission wavelength) indicate...

The invention is used for remote qualitative and quantitative analyzes of environmentally hazardous liquid spills, and is intended for oil, oil products and organic chemicals to identify natural, processed, ballast and bilge water, using the original laser scanning apparatus in the air. Pulsed laser that emits several wavelengths in the visible and...

The invention discloses the method for remote qualitative and quantitative analyzes of environmentally hazardous liquid spills, and is intended for oil, oil products and organic chemicals to identify natural, processed, ballast and bilge water, using the original laser scanning apparatus in the air. Pulsed laser that emits several wavelengths in th...

The paper reviews results of field studies and pilot projects with airborne Fluorescent Laser Spectrometers (FLS-lidars) carried out in 2003-2004 in sea and lake waters as well as watersheds. Those studies were aimed at locating areas with water quality deviations from normal state due to municipal and agriculture discharges and chemical pollution....

The present invention discloses a portable, reliable, automated and simple device using Spectral Fluorescence Signature technology (SFS) for fast and accurate drug detection, quantification and data storage. The present also discloses a method for using Spectral Fluorescence Signature technology (SFS) for fast and accurate drug detection, quantific...

The invention provides a method for automatic encrypted marking of liquids and for identifying liquids marked by using this method. For marking certain number of markers is selected and for every marker a random number is generated, which define the amount of a marker used. Based on the number of markers, their measured concentrations and the relat...

Delay between the time when natural disaster, for example, oil accident in coastal water, occurred and the time when environmental protection actions, for example, water and shoreline clean-up, started is of significant importance. Mostly remote sensing techniques are considered as (near) real-time and suitable for multiple tasks. These techniques...

The creation of rapid and simple method of PAH detection and identification in edible fats and oils using procedure of food lipids solubilizing in hexane and transferring of PAH into DMSO thereby increasing the efficiency of PAH fluorescence, and using Spectral Fluorescence Signature (SFS) method for rapid spectral distinguishing of PAH fluorescenc...

ABSTRACT The paper presents recent results of field experiments with airborne fluorescent lidar FLS-A based on excimer,laser and multichannel,detector. Helicopter installation was used to monitor water and land areas of oil transportation and storage. Techniques for real-time data acquisition and processing are described based on compiled and syste...

The paper overviews capabilities of a multi-wavelength laser remote sensing technique in real-time analytical monitoring of aquatic and terrestrial targets. The conceptual design of the Fluorescent Lidar Spectrometer (FLS) - a compact, multipurpose analytical lidar - is described. Its modular architecture allows efficient research and routine monit...

In many environmental and industrial applications decomposing the conglomerate of organic compounds in water into single chemical ingredients for subsequent analysis is time consumable and complicated task. The most productive approach to On - Line diagnostics is to treat the object as an integral spectroscopic sample, characterized by certain spec...

This work presents original results in the applications of laser-induced fluorescence techniques, including the remote modification of total luminescent spectroscopy (TLS) proposed by some of the authors earlier, to field studies of spatial distributions of marine organic matter. Descriptions of measuring technologies and of the results obtained ar...

The advantages and problems of the application of actively excited fluorescence in natural phyto- plankton analysis are discussed. The focus is made to a correct prediction of pigment concentrations by fluorescence data. The results of high resolution mapping of chlorophylls and phycobilins in the Gotland Basin (Baltic Sea) during Cyanobacterial bl...

The variability of quantitative fluorescence characteristics of Chlorella sp. (strain TV217) pigments during culture growth under different nitrogen conditions was studied by using excitation spectra of in vivo fluorescence. The ratio of chlorophyll-b/chlorophyll-a, calculated for both concentration and fluorescence levels, was stable for the selec...

The flow-through spectrofluorometers, FLUO-IMAGER, were developed to measure the abundance of phytoplankton, including the analysis of pigment composition and concentration of organic pollution and dissolved organic matter (DOM), in continuous mode. The measurements can be carried out without the time-consuming pretreatment of water samples. The an...

The Spectral Fluorescent Signatures (SFS) technology has been applied to investigate the seasonal and annual variability of Dissolved Organic Mater (DOM), Dissolved Organic Carbon (DOC), phytoplankton and organic pollution in Estonian rivers and coastal zone. Statistical analysis of data collected in 1996-1998 allowed one to perform the classificat...

The results of field studies of phytoplankton and dissolved organic matter (DOM) in the Gulf of Riga in August–September 1993, June 1994 and April 1995 are presented. Actively excited fluorescence in UV- and visible spectral regions was used to investigate spatial distributions of DOM, Chl a, carotenoids and phycoerythrin in surface water. The fluo...

The temporal and spatial short-term variability of phytoplankton biomass was investigated in spring, summer and autumn in a polygon crossing the north Norwegian shelf between the two coastal banks Sveinsgrunnen and Malangsgrunnen. In addition to traditional sampling (CTD, nutrients and chlorophyll a), a remote sensing lidar technique was used to co...

Used in fast screening mode the Spectral Fluorescence Signature (SFS) technique decreases the number of routine and time-consuming laboratory analyses significantly. This makes the analysis system appropriate for a number of different application fields including waste water monitoring from industrial works, monitoring surface waters in areas with...

In many industrial and environmental applications decomposing the mixture of substances in the water into its various chemical components, for subsequent analysis, is a very complicated task. The most productive approach to on-line diagnostics is to treat the object as an integral spectroscopic sample, characterized by certain specific Spectral Flu...

The set of laboratory experiments with oil contaminated water has been performed to investigate the variability of Spectral Fluorescent Signatures (SFS) caused by environmental conditions. The sample volumes of sea water were polluted by diesel oil emulsion in a water volume. The dynamics of SFS (both in shape and intensity) was measured and analys...

The unit for real-time detection of the amount of organic compounds in water, which is composed of optically connected ultra-violet light source (1), the excitation scanning spectral device (2), the electronically controlled mechanical shutter (3), the quartz optical splitter (5) and the first photoelectric detector (4), wherein the quartz splitter...

Report Series of Geophysics, University of Helsinki, nr. 38, 47-58 Optical properties of phytoplankton are sensitive markers of the water environment. In vivo spectral analyses can be used as a tools for studying seasonal and spatial dynamics of the phytoplankton communities at chemotaxonomic level. Measurements can be performed at defferent levels...

The application of SFS techniques in environmental analysis provides the possibility to carry out the rapid qualitative diagnostics of organic compounds in natural water. This allows the use of phytoplankton pigments as natural fluoroindicators of the taxonomic groups and allows the monitoring of water quality by analysis of pigment composition in...

The paper summarizes the results obtained with lidar in different applications of remote sensing of marine environment. The Fluorescent Lidar Systems (FLS) based on excimer and dye-lasers and multichannel optical detector is described. The optimization of operational parameters of the FLS lidar made it possible to use module construction of lidar o...

The application of two-dimensional (2-D) fluorescent technique for automatic monitoring of organic compounds in water is discussed. For recognition and quantitive estimation of water organics the calibrated library of spectral signatures was used. The library included the 2-D fluorescence spectra of phenols, oil shale oils and Dissolved Organic Mat...

An approach of on-line fluorescent analysis of organic compounds in a water is described based on multiwavelength sensing of water environment. Developed techniques are realized in remote mode to inspect large water surfaces as well as in flow-trough mode to diagnose the water quality in the pipes and open streams. The tuneable fluorescent lidars F...

The results of field remote sensing of brackish - water phytoplankton by tunable lidar on board of a research vessel are presented. The authors have developed study approach based on spectral signature method and the method of selective excitation of phytoplankton pigments to diagnose the variability of pigment composition of phytoplankton communit...

The results of field remote sensing of brackish - water phytoplankton by tunable lidar on board of a research vessel are presented. The authors have developed study approach based on spectral signature method and the method of selective excitation of phytoplankton pigments to diagnose the variability of pigment composition of phytoplankton communit...

The results of field remote sensing of brackish - water phytoplankton by tunable lidar on board of a research vessel are presented. The authors have developed study approach based on spectral signature method and the method of selective excitation of phytoplankton pigments to diagnose the variability of pigment composition of phytoplankton communit...

Fluorescence spectral signatures from 28 algal cultures are described.The cultures are split into four groups according to their accessory pigments. Phycocyanin and phycoerythrin, characteristic pigments of cyanobacteria, form groups I and II. The characteristic pigment found in group III is chlorophyll b (green and rasinophyte algae) and in group...

The techniques of Selective Excitation of Phytoplankton Pigments (SEPP) is used to analyse pigment composition of mixed phytoplankton community in remote mode. Such an approach incomes the creation of a basic spectral signature catalogue of the most important phyto-plankton species and the comparative analysis of the laser induced fluorescence of n...

MTS Journal, vol. 28, nr. 3, 50-58 The techniqes of selective Exciation of Phytoplankton Pigments (SEPP) is used to analyze pigment composition of mixed phytoplankton community in remote mode. Such an approach involves the creation of a basis spectral signature catalogue of the most important phytoplankton species and the comparative analysis of th...

Journal of Plankton Research, vol. 16, nr. 10, 1315-1327 Fluorescence spectral signatures from 28 algal cultures are described. The cultures are split into four groups according to their accessory pigments. Phycocyanin and phycoerythrin, characteristic pigments of cyanobacteria, form groups I and II. The characteristic pigment found in group III is...

The results of remote laser sensing of brackishwater phytoplankton on board a research vessel are presented. Field data of laser-induced fluorescence of phytoplankton obtained during the several cruises in the mouth of the Gulf of Finland are compared with the results of standard chlorophyll a analysis of water samples and phytoplankton species det...

Field measurements of the spatial distribution of phytoplankton by tunable lidar on board a research vessel are reported. The possibility of applying laser remote sensing to the diagnostics of hydrophysical processes in the upper layers of the sea is discussed. Twelve tracks in different directions were sensed. Marked periodical structures were obs...

Field measurements of the spatial distribution of phytoplankton by tunable lidar on board a research vessel are reported. The possibility of applying laser remote sensing to the diagnostics of hydrophysical processes in the upper layers of the sea is discussed. Twelve tracks in different directions were sensed. Marked periodical structures were obs...

The results of remote field diagnostics of brackish-water phytoplankton by tunable lidar on board a research vessel are presented. The authors have developed a study approach based on the spectral signature method and the method of selective excitation of phytoplankton pigments to detect pigment composition of phytoplankton communities in vivo.

Humic substances (HS) are considered as a variable background in an approach in which the total luminescence spectroscopy (TLS) technique was used for the analysis of organic pollutants dissolved in natural water. The high spectral variability of HS two-dimensional fluorescence spectra collected from sea areas in the central part of the English Cha...

Experimental results on remote sea sensing from a research vessel by wavelength tunable lidar with a multichannel optical detector are given. The performances of the spectral signatures method for diagnostics of water media containing phytoplankton pigments, dissolved organics, oil pollutants at low concentration levels, etc., are discussed.

In undertaking the rapid diagnostics of water conditions (for organic impurities, eutrophication etc.), it is expedient to confine the effort to establishing the statistically normal state and departures from it rather than to seek the full chemical composition of the medium. What others have termed spectral signatures obtained by such methods as t...

The work shows the results of applying the Total Luminescent Spectroscopy (TLS) to the diagnostics of natural water conditions, as well as a study of spatial variability of sea phytoplankton and dissolved organic matter using a laser technique. The block-diagram of a tunable laser remote spectrometer developed by the authors is presented. -from Aut...