Chemistry, Analytical Chemistry, Chemical Engineering
18
Scopus Publications
Scopus Publications
Sex-specific role of microglia in Δ9-tetrahydrocannabinol-induced disruption of fear memory reconsolidation Ana Maria Raymundi, Nathalie Carla Cardoso, Gabriel Costa Lourenço, Ruliam Queiroz, Maressa D. Dolzan, Luciano Vitali, Erika Meyer, Sabrina Francesca Lisboa, Francisco Silveira Guimarães, Graziano Pinna, Leandro José Bertoglio, Cristina Aparecida Jark Stern Neuropsychopharmacology, 2026 In PTSD, microglia are more engaged in fear-related circuits, where they participate in fear memory processing responses. The reconsolidation-impairing effect of Δ⁹-tetrahydrocannabinol (THC), the primary psychoactive constituent of Cannabis, is typically linked to cannabinoid type-1 receptor (CB1) signaling. THC also engages peroxisome proliferator-activated receptor gamma (PPARγ), and both CB1 and PPARγ modulate neuroimmune processes, including microglial activity. This dual mechanism suggests that THC’s impact on fear memory reconsolidation may extend beyond classical cannabinoid signaling. We hypothesize that THC disrupts contextual fear memory reconsolidation via microglial recruitment in the dorsal hippocampus (DH) through a sex-specific engagement of CB1 and PPARγ. Adult male and female Wistar rats underwent contextual fear conditioning, followed by THC (0.002 mg/kg, i.p.) or vehicle administration immediately after memory retrieval. Microglial involvement was assessed using immunofluorescence and pharmacological and chemogenetic inhibition in DH. The role of CB1 and PPARγ receptors was assessed via intra-DH selective antagonist infusion. THC impaired reconsolidation in males and females. In males, fear memory retrieval increased microglial engagement in the DH CA1 subfield, which THC further enhanced. Pharmacological and chemogenetic inhibition of microglia, as well as selective CB1 and PPARγ antagonism, blocked THC’s effects in males. In females, THC-induced reconsolidation blockade was cycle-dependent, occurring at estrus and diestrus but not at proestrus, and was mediated exclusively through CB1 activation. These findings identified sex-specific neuroimmune pathways mediating THC’s reconsolidation impairment, offering a mechanistic basis for novel sex-tailored therapeutic opportunities.
Development of a Multianalyte Method for the Determination of Phenolic Compounds in Residues from Beverage Production Using a Cyclofructan-Based Column in HILIC-MS/MS Mayara da Silva, Maressa D. Dolzan, Gustavo A. Micke, Luciano Vitali Journal of the Brazilian Chemical Society, 2025 This study expands and shows the versatility of applications in hydrophilic interaction chromatography coupled with triple quadrupole mass spectrometry (HILIC-MS/MS) using a FRULIC-N column to determine 31 phenolic compounds in beverage industry residues (coffee, apple juice, beer, and wine). Optimization, via Doehlert design, determined the acetonitrile proportion (50-90%) and pH (3.0-7.0) in the mobile phase (MP). A 22 factorial design assessed the concentration of ammonium acetate (10-110 mmol L-1) in the MP and column temperature (20-60 °C). Injection volume (5-45 µL) was univariately optimized. Separations at 60 °C reduced chromatographic run time to less than 11 min. Gradient elution (500 µL min-1) employed an MP comprising acetonitrile and ammonium acetate (110 mmol L-1, pH 7). Validation demonstrated average coefficient of determination (R2 ) 0.9707, limit of detection 0.001-0.503 mg L-1 and quantification 0.004-1.524 mg L-1, precision < 12.2%, recovery 92.4-110.8%. The method was applied to five residues, indicating its viability for determining phenolics in beverage production residues.
Enantiomeric separation of citalopram analogues by HPLC using macrocyclic glycopeptide and cyclodextrin based chiral stationary phases Maressa D. Dolzan, Yang Shu, Jonathan P. Smuts, Hans Petersen, Peter Ellegaard, Gustavo A. Micke, Daniel W. Armstrong, Zachary S. Breitbach Journal of Liquid Chromatography and Related Technologies, 2016 The enantiomeric separation of a novel series of twenty-eight racemic mixtures of citalopram analogues was performed by high performance liquid chromatography (HPLC). Due to the effectiveness of citalopram as an antidepressant drug, the development of new compounds based on its chemical structure is interesting, and their enantiomeric separation is needed to allow further pharmacokinetic studies. Several bonded cyclodextrin (both native and derivatized) and macrocyclic glycopeptide based chiral stationary phases (CSPs) were evaluated for their ability to separate this set of compounds via HPLC. Polar ionic, polar organic, and reversed phase modes were tested. Twenty-five of the racemic mixtures were separated with resolutions and enantiomeric selectivities up to 2.9 and 1.33, respectively. A total of eighteen baseline separations were achieved, while seven compounds were partially separated. Vancomycin based columns operated in the polar ionic mode resulted in the greatest number of separations. Lastly, the chromatographic behaviors of similar compounds were compared based on their chemical structure and also on the chiral selectors used. GRAPHICAL ABSTRACT
Topiramate: A Review of Analytical Approaches for the Drug Substance, Its Impurities and Pharmaceutical Formulations Eduardo Costa Pinto, Maressa Danielli Dolzan, Lucio Mendes Cabral, Daniel W. Armstrong, Valéria Pereira de Sousa Journal of Chromatographic Science, 2016 An important step during the development of high-performance liquid chromatography (HPLC) methods for quantitative analysis of drugs is choosing the appropriate detector. High sensitivity, reproducibility, stability, wide linear range, compatibility with gradient elution, non-destructive detection of the analyte and response unaffected by changes in the temperature/flow are some of the ideal characteristics of a universal HPLC detector. Topiramate is an anticonvulsant drug mainly used for the treatment of different types of seizures and prophylactic treatment of migraine. Different analytical approaches to quantify topiramate by HPLC have been described because of the lack of chromophoric moieties on its structure, such as derivatization with fluorescent moieties and UV-absorbing moieties, conductivity detection, evaporative light scattering detection, refractive index detection, chemiluminescent nitrogen detection and MS detection. Some methods for the determination of topiramate by capillary electrophoresis and gas chromatography have also been published. This systematic review provides a description of the main analytical methods presented in the literature to analyze topiramate in the drug substance and in pharmaceutical formulations. Each of these methods is briefly discussed, especially considering the detector used with HPLC. In addition, this article presents a review of the data available regarding topiramate stability, degradation products and impurities.
High-Throughput Analysis of Lidocaine in Pharmaceutical Formulation by Capillary Zone Electrophoresis Using Multiple Injections in a Single Run Andressa C. Valese, Daniel A. Spudeit, Maressa D. Dolzan, Lizandra C. Bretanha, Luciano Vitali, Gustavo A. Micke Journal of Analytical Methods in Chemistry, 2016 This paper reports the development of a subminute separation method by capillary zone electrophoresis in an uncoated capillary using multiple injection procedure for the determination of lidocaine in samples of pharmaceutical formulations. The separation was performed in less than a minute leading to doing four injections in a single run. The cathodic electroosmotic flow contributed to reducing the analyses time. The background electrolyte was composed of 20 mmol L−12-amino-2-(hydroxymethyl)-1,3-propanediol and 40 mmol L−12-(N-morpholino)ethanesulfonic acid at pH 6.1. The internal standard used was benzylamine. Separations were performed in a fused uncoated silica capillary (32 cm total length, 23.5 cm effective length, and 50 μm internal diameter) with direct UV detection at 200 nm. Samples and standards were injected hydrodynamically using 40 mbar/3 s interspersed with spacer electrolyte using 40 mbar/7 s. The electrophoretic system was operated under constant voltage of 30 kV with positive polarity on the injection side. The evaluation of some analytical parameters of the method showed good linearity(r2>0.999), a limit of detection 0.92 mg L−1, intermediate precision better than 3.2% (peak area), and recovery in the range of 92–102%.
Simultaneous determination of herbicides in rice by QuEChERS and LC-MS/MS using matrix-matched calibration Andrey M. Rebelo, Maressa D. Dolzan, Melina Heller, Francisco C. Deschamps, Gilberto Abate, Gustavo A. Micke, Marco T. Grassi Journal of the Brazilian Chemical Society, 2016 The main objective of the present work was to validate a chromatographic method to determine herbicides commonly applied in the irrigated rice farming. For this, matrix-matched calibration was employed along with the extraction and clean-up of the samples by quick, easy, cheap, effective, rugged and safe (QuEChERS) method and determination of the analytes by high performance liquid chromatography tandem mass spectrometry (LC-MS/MS) with electrospray ionization in the positive mode. By this method, it was possible to achieve the ionization and detection of a total of 18 herbicides, with quantification of 12 of them. The method presented adequate precision and accuracy according to the European Commission and the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) guidelines for analytes in low concentrations. The limits of quantification ranged from 0.015 μg g-1 for oxadiazon to 0.165 μg g-1 for imazapyr. The method showed good linearity with R2> 0.99 and recovery values from 92 to 103%. The proposed protocol is adequate for monitoring bispyribac-sodium, cyclosulfamuron, cycloxydim, clomazone, ethoxysulfuron, fenoxaprop-p-ethyl, imazapic, imazapyr, imazethapyr, metsulfuron-methyl, oxadiazon and thiobencarb in rice grains in concentrations up to 109 times lower than the maximum residue limits established by the Brazilian Health Surveillance Agency (ANVISA) for these compounds in rice samples.
