Time filter

Source Type

Trofin I.G.,Central Laboratory for Drug Analysis and Profiling | Vlad C.C.,Central Laboratory for Drug Analysis and Profiling | Dabija G.,Central Laboratory for Drug Analysis and Profiling | Filipescu L.,University of Bucharest
Revista de Chimie | Year: 2011

Thaim of the present paper was to investigate the stability of cannabinoids in herbal cannabis upon longterm storage. The content of tetrahydrocannabinol (Δ9-THC), cannabinol (CBN), and cannabidinol (CBD) in herbal cannabis from ten different regions of the world were measured for up to four years of storage in darkness at 4°C and in natural light of laboratory at 2°TC. The degradation of Δ9-THC was faster in the first year than in subsequent years, and more pronounced for the samples exposed to light at 22°C than those stored in darkness at 4 °C. The content of CBN increases during the storage and the increase is more pronounced for the samples exposed to light at 22 °C than those stored in the darkness at 4°C. These results are consistent with those obtained for Δ9-THC. Also, a new criterion for the chemical potency ranking in different herbal cannabis grades was approached on the basis of the Δ9-THC degradation kinetics.


Bobirica C.,Polytechnic University of Bucharest | Dabija G.,Central Laboratory for Drug Analysis and Profiling | Bobirica L.,Polytechnic University of Bucharest | Mihai M.,Polytechnic University of Bucharest | Costache C.,Polytechnic University of Bucharest
Environmental Engineering and Management Journal | Year: 2014

The performance of some complex coagulants derived from weak and medium anionic polymers and medium cationic surfactant in coagulation-flocculation process for water treatment was experimentally investigated by carrying out kinetic studies and by determining the optimum coagulant dose. The complex coagulants were prepared from weak anionic and medium anionic copolymers of acrylamide and sodium acrylate with the commercial names Praestol 2515 and Praestol 2540, and medium cationic surfactant derived from triethanolamine with the commercial name Tetranyl AT-7590. The coagulation-flocculation process was studied for suspensions of kaolin particles in tap water. The electro-kinetic studies revealed that the addition of surfactant leads to a significant decrease of coagulant concentration for which the electro-kinetic potential of the dispersion medium becomes zero. The favorable influence of the addition of surfactant also resulted from the kinetic studies. Thus, the formation of some large flocks leads to shortening the flocculation period. These results are consistent with those obtained for sedimentation velocity, sludge volume and separation efficiency. © 2014, (publisher). All rights reserved.


Trofin I.G.,Central Laboratory for Drug Analysis and Profiling | Dabija G.,Central Laboratory for Drug Analysis and Profiling | Vaireanu D.-I.,Polytechnic University of Bucharest | Filipescu L.,Polytechnic University of Bucharest
Revista de Chimie | Year: 2012

The objective of this paper was to investigate the changes in chemical potency of cannabis resin depending on its long-term storage conditions. In this respect, the content of tetrahydrocannabinol (Δ 9-THC), cannabinol (CBN), and cannabidiol (CBD) in cannabis resin derived from three different seizures made by criminal prosecution authorities from Romania were measured for up to four years of storage in darkness at 4°C and in laboratory light at 22°C. The results revealed a steadily decay of Δ 9-THC over the entire storage period. In addition, the samples exhibited a more pronounced decay for the sample exposed to light at 22°C than those stored in darkness at 4°C. For CBD decay, the same trend is valid also. On the contrary, the content of CBN raised steadily during storage, and the raise is more pronounced for the samples exposed to light at 22°C than those stored in the darkness at 4°C.


Trofin I.G.,Central Laboratory for Drug Analysis and Profiling | Dabija G.,Central Laboratory for Drug Analysis and Profiling | Vaireanu D.-I.,Polytechnic University of Bucharest | Filipescu L.,Polytechnic University of Bucharest
Revista de Chimie | Year: 2012

The paper presents the results of an experimental study regarding the stability of cannabis oil during its long-term storage in different conditions. The content of major cannabinoids, namely tetrahydrocannabinol (δ 9-THC), cannabinol (CBN), and cannabidiol (CBD) contained in two batch samples of cannabis oil seizures made by criminal prosecution authorities from Romania was measured during their storage over a period of four years in darkness at 4 °C and in laboratory light at 22 °C. The results revealed a steadily decay of δ 9- THC over the entire storage period from a very high initial content up to a relatively low final content. A slight difference regarding the degree of decay of δ 9-THC between the two storage conditions was recorded, meaning that this is more pronounced when the samples were exposed to light at 22°C. The same trend was recorded for CBD. As expected, the content of CBN increases during storage and the increase is higher when the samples were exposed to light at 22 °C.


Bobirica C.,Polytechnic University of Bucharest | Bobirica L.,Polytechnic University of Bucharest | Dabija G.,Central Laboratory for Drug Analysis and Profiling | Mihai M.,Polytechnic University of Bucharest
Environmental Engineering and Management Journal | Year: 2012

This paper presents the physicochemical and rheological properties of some complex coagulants derived from the weak and medium anionic polymers and medium cationic surfactant in order to evaluate the opportunity to use them in destabilizing and removing the colloidal systems from water and wastewater. In this respect, weak anionic and medium anionic copolymers of acrylamide and sodium acrylate with commercial names of Preastol 2515 and Preastol 2540, and a medium cationic surfactant derived from triethanolamine with commercial name of Tetranyl AT-7590 were used in order to obtain these complex coagulants. Complex coagulants formation was revealed based on changes in physical properties of the solutions such as superficial tension and apparent viscosity. The experimental results suggest the formation mechanism of the complex by grafting of surfactant micelles on the chain of the polymer, a process that occurs in the range of surfactant concentrations ranging between its critical aggregation concentration and critical micellar concentration. Loss of viscoelastic properties of complex solutions has a beneficial effect on the interaction between colloidal particles and complex coagulant and subsequently, on the entire coagulation - flocculation process. Although complex are formed by electrostatic attraction forces they have a good mechanical strength evidenced by maintaining of the rheological characteristic at high shear rate. Therefore, it is expected that these associations to withstand the intense mechanical conditions that occur during contact of colloidal solution with complex solution.


Trofin I.G.,Central Laboratory for Drug Analysis and Profiling | Vlad C.C.,Central Laboratory for Drug Analysis and Profiling | Noja V.V.,Central Laboratory for Drug Analysis and Profiling | Dabija G.,Central Laboratory for Drug Analysis and Profiling
UPB Scientific Bulletin, Series B: Chemistry and Materials Science | Year: 2012

The appearance on the illicit drug market of new hybrid varieties of the cannabis plant with a high potency requires a continuous development of some appropriate methods for their identification and characterization in order to establish their arias of origin and trafficking routes. In this work it was identified and characterized from the point of view of content in cannabinoids, phenotype and age a series of hybrid varieties of cannabis seized by competent authorities in Romania.

Loading Central Laboratory for Drug Analysis and Profiling collaborators
Loading Central Laboratory for Drug Analysis and Profiling collaborators