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1.
BMC Chem ; 18(1): 160, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39198835

RESUMO

BACKGROUND: The proposed research study introduces independent concentration extraction (ICE) as a novel UV-Vis spectrophotometric approach. The approach can be used for extracting the concentration of two analytes with severely overlapped spectra from their binary mixtures. ICE is based on spectral extraction platform involving simple smart successive methods that can directly extract the original zero order spectra of the analytes at their characteristic (λmax). Chlorpheniramine maleate (CPM) and Levocloperastine fendizoate (LCF) are two commonly co-formulated drugs in cough preparations. The combined mixture was used to confirm the validity of the developed ICE tool. Another less green HPTLC was developed for the first time to separate both drugs and help also in confirming the proposed tool. METHODS: For the simultaneous determination of CPM and LCF, two ecologically friendly techniques were employed. The first approach encompasses the use of the ICE spectrophotometric method that could be successively applied for extracting the concentration of two analytes with severely overlapped unresolved spectra in their binary mixtures. Other complementary methods aiming at original spectral extraction; including spectrum subtraction (SS) and unity subtraction (US) were also successfully employed to resolve the zero order spectra of the combined drugs with all their characteristic features and peaks. The second technique used, a high-performance TLC-densitometric one, was performed on silica plates with silica plates F254 and a mobile phase with a ratio of 3:3:3:1 by volume of toluene, ethanol, acetone, and ammonia as a developing system at 230 nm. RESULTS: The presented extraction approach was executed without any optimization steps or sample pretreatment for the simultaneous determination of CPM and LCF. The method was found to be valid for their determination within concentration range of 3.0-30.0 µg mL-1 for both drugs. For HPTLC method, the resulting Rf values of CPM and LCF were 0.37 and 0.78, within concentration ranges of 0.3-4.0 µg/spot and 0.8-10.0 µg/spot, respectively. Greenness assessment of both developed methodologies showed that the HPTLC method is less green than the spectrophotometric method, yet with comparable sustainability when it comes to the used technique. CONCLUSION: The procedures were found to be selective, accurate, and precise for analysis of the studied binary mixture. Furthermore, the environmental impact of the introduced methods was assessed using novel greenness metrics, namely AGREE and Green Analytical Procedure Index (GAPI) to prove their ecological safety. In addition, white analytical chemistry (WAC) evaluation metric was employed to ensure the synergy and coherence of analytical, practical, and ecological attributes.

2.
Biol Trace Elem Res ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143445

RESUMO

With the global increase in the use of dietary supplements to provide nutrients in one's regular diet, these supplements' potential health risks and benefits have become a topic of significant interest. Interestingly, as dietary supplements, the Food and Drug Administration (FDA) in the United States (USA), Europe, and most countries do not require manufacturers and distributors to obtain approval or provide safety assessments before marketing those products. This research explores for the first time 16 heavy, trace and macro-elemental contents, namely, As, Ni, Cd, Pb, Cu, Co, Mn, Cr, Zn, V, Fe, Al, K, Na, Mg, and Ca, within 24 nutraceutical and herbal supplements marketed in Oman. The research is focusing on ensuring their compositions, concentrations, and freedom of toxic elements. ICP-OES was utilized, preceded by a microwave digestion technique to digest the samples in concentrated HNO3 and HCl (3:1, v/v). The method was validated within linear ranges of 0.03-5.00 ppm and 1.0-200.0 ppm for micro- and macro-elements, respectively, with %recoveries ranging from 90 to 104%. The limits of detection ranged from 0.01 to 0.09 and 0.14 to 0.30 ppm, while the limits of quantification ranged from 0.03 to 0.28 and 0.46 to 0.91 ppm for micro- and macro-elements, respectively. The detected levels were compared to online databases for risk assessment. Although As and Cd were not detected in all samples, Pb was found in nine samples, with some exceeding regulated limits of exposure. About 80% of the samples contained Al, of which two samples were susceptible to serious health risks of exceeding exposure limits in their compiled doses. The locally harvested Omani herbal supplements revealed significant amounts of Zn, Mg, Mn, and Cu. The results highlighted the potential risks associated with both dosage compliance and labeling discrepancies.

3.
J Fluoresc ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38976089

RESUMO

The diagnosis of prostate cancer has been evolving in the current decade, with expected mortality rates of 499,000 death by the year 2030. Apalutamide (APL) has been approved in 2018 as the first drug for the controlling of prostate cancer. APL significant success warrantied its high global sales, which are expected to surpass 58% of segment market sales (together with another drug; enzalutamide). Therefore, new, fast and environmentally friendly analytical methods are required for its determination for the quality control and biological monitoring purposes. The proposed research designs and evaluates the first fluorimetric approach based on novel porous green boron-doped carbon quantum dots (B@CDs) for the determination of APL in biopharmaceutical matrices. The synthetic approach has high quantum yield (31.15%). B@CDs were characterized using several tools, including transmission electron microscopy (TEM), dynamic light scattering (DLS), FTIR and Energy dispersive X-ray spectroscopy (EDX) which proved their improved surface properties with an average nano-diameter of 3.0 nm. The interaction between B@CDs and APL led to enhancement their fluorescence at 441 nm (excitation at 372 nm). The approach was validated for the determination of APL within concentration range of 15.0-700.0 ng mL- 1 with quantification limit LOQ 4.37 ng mL- 1 and detection limit LOD 1.44 ng mL- 1. The approach was successfully applied for the determination of APL in human plasma and pharmaceutical monitoring of its marketed tablet form. Then, the approach was assessed for its environmental impact using different metrics and proved its ecological greenness.

4.
Curr Issues Mol Biol ; 46(7): 6805-6819, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39057048

RESUMO

Escherichia coli is a major cause of serious infections, with antibiotic resistance rendering many treatments ineffective. Hence, novel strategies to combat this pathogen are needed. Anti-virulence therapy is a promising new approach for the subsequent era. Recent research has examined the impact of sub-inhibitory doses of ascorbic acid and paracetamol on Escherichia coli virulence factors. This study evaluated biofilm formation, protease production, motility behavior, serum resistance, expression of virulence-regulating genes (using RT-PCR), and survival rates in a mouse model. Ascorbic acid significantly reduced biofilm formation, protease production, motility, and serum resistance from 100% in untreated isolates to 22-89%, 10-89%, 2-57%, and 31-35% in treated isolates, respectively. Paracetamol also reduced these factors from 100% in untreated isolates to 16-76%, 1-43%, 16-38%, and 31-35%, respectively. Both drugs significantly down-regulated virulence-regulating genes papC, fimH, ompT_m, stcE, fliC, and kpsMTII. Mice treated with these drugs had a 100% survival rate compared with 60% in the positive control group control inoculated with untreated bacteria. This study highlights the potential of ascorbic acid and paracetamol as anti-virulence agents, suggesting their use as adjunct therapies alongside conventional antimicrobials or as alternative treatments for resistant Escherichia coli infections.

5.
Luminescence ; 39(6): e4801, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38855811

RESUMO

Atopic dermatitis (AD) is a persistent, inflammatory skin condition that impacts approximately 15 to 20% of children and 1 to 3% of adults globally. Common skin manifestations include papules, papulovesicular, and brown or red patches with swelling, crusting, and flaking. Therefore, the drug abrocitinib (ABR) was approved by the US FDA as an oral treatment for atopic dermatitis. The present study outlines the development of innovative, thermostable, and pH-stable organic solvent-free nitrogen-doped carbon dots (N@CQDs) synthesized through a one-step method for evaluating ABR with a notable quantum yield of 33.84% to minimize the use of organic solvents. Their cost-effectiveness, eco-friendly characteristics, and outstanding photocatalytic properties have established them as a promising alternative to conventional luminescent techniques like fluorescent dyes and luminous derivatization technique. The reaction of ABR with N@CQDs led to a significant decrease in the luminescent response of the produced green and stable carbon quantum dots at 513 nm. The detection range was determined to be 1.0-150.0 ng mL-1, with a lower limit of quantitation (LOQ) equal to 0.52 ng mL-1 based on the linear graph. The green method effectively used for analysis of ABR in pharmaceutical tablets and pharmacokinetic study with high sensitivity.


Assuntos
Carbono , Nitrogênio , Pontos Quânticos , Pontos Quânticos/química , Carbono/química , Nitrogênio/química , Humanos , Pirimidinas/química , Pirimidinas/sangue , Pirimidinas/síntese química , Fluorometria , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Solventes/química , Estrutura Molecular
6.
AAPS PharmSciTech ; 25(5): 95, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710921

RESUMO

Verapamil hydrochloride (VRP), an antihypertensive calcium channel blocker drug has limited bioavailability and short half-life when taken orally. The present study was aimed at developing cubosomes containing VRP for enhancing its bioavailability and targeting to brain for cluster headache (CH) treatment as an off-label use. Factorial design was conducted to analyze the impact of different components on entrapment efficiency (EE%), particle size (PS), zeta potential (ZP), and percent drug release. Various in-vitro characterizations were performed followed by pharmacokinetic and brain targeting studies. The results revealed the significant impact of glyceryl monooleate (GMO) on increasing EE%, PS, and ZP of cubosomes with a negative influence on VRP release. The remarkable effect of Poloxamer 407 (P407) on decreasing EE%, PS, and ZP of cubosomes was observed besides its influence on accelerating VRP release%. The DSC thermograms indicated the successful entrapment of the amorphous state of VRP inside the cubosomes. The design suggested an optimized formulation containing GMO (50% w/w) and P407 (5.5% w/w). Such formulation showed a significant increase in drug permeation through nasal mucosa with high Er value (2.26) when compared to VRP solution. Also, the histopathological study revealed the safety of the utilized components used in the cubosomes preparation. There was a significant enhancement in the VRP bioavailability when loaded in cubosomes owing to its sustained release favored by its direct transport to brain. The I.N optimized formulation had greater BTE% and DTP% at 183.53% and 90.19%, respectively in comparison of 41.80% and 59% for the I.N VRP solution.


Assuntos
Administração Intranasal , Encéfalo , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Glicerídeos , Mucosa Nasal , Tamanho da Partícula , Verapamil , Administração Intranasal/métodos , Animais , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Verapamil/administração & dosagem , Verapamil/farmacocinética , Distribuição Tecidual , Glicerídeos/química , Mucosa Nasal/metabolismo , Disponibilidade Biológica , Ratos , Bloqueadores dos Canais de Cálcio/farmacocinética , Bloqueadores dos Canais de Cálcio/administração & dosagem , Poloxâmero/química , Masculino , Química Farmacêutica/métodos , Ratos Wistar , Nanopartículas/química
8.
RSC Adv ; 14(15): 10445-10451, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38567336

RESUMO

Avapritinib (AVA) is the first medication authorized by the US-FDA in 2020 for the management of gastrointestinal stromal tumours (GISTs) that can't be treated by surgery. Cancer is among the most common causes of death worldwide and is the second most common cause of death after cardiovascular disease. Therefore, a quick, easy, sensitive, and straightforward fluorimetric approach was used to analyse AVA in pharmaceutical materials and blood plasma (pharmacokinetic). The suggested technique relies on 2% sodium dodecyl sulphate (SDS, pH 4) micellar system augmentation of the fluorescence of the tested drug. The technique demonstrated high relative fluorescence intensity (RFI) at 430 nm after excitation at 340 nm. Concentrations ranging from 20.0-400.0 ng mL-1 with a limit of quantitation of 9.47 ng mL-1 were used to obtain luminescence data for the studied medicine. In addition, the quantum yield of the AVA fluorescence was increased with the gradual addition of a surfactant at a concentration above its critical micellar level. This knowledge has been exploited to enhance the effectiveness of a spectrofluorometric technique for the estimation of AVA in human plasma (98.95 ± 1.22%) and uniformity tests with greenness assessments. The conditions for enhanced fluorescence were optimized and fully validated using US-FDA and International Conference on Harmonization (ICH) rules. This innovative strategy was expanded for AVA stability research in human plasma across various circumstances. This approach is an eco-friendly solution compared to traditional testing methods that use hazardous chemicals.

9.
Biol Trace Elem Res ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656680

RESUMO

Tobacco smoking is becoming one of the major worldwide concerns regarding environmental pollution as well as health threats. In 2005, the World Health Organization (WHO) released the Framework Convention On Tobacco Control (FCTC), which outlined protocols for controlling tobacco products. Oman was one of the leading countries to follow these protocols; however, Egypt has only followed these protocols recently in 2020. One of the main challenges in tobacco product control is the variation in their trace element's types and amounts from country to country owing to differences in agriculture techniques and used chemical additives. Smoking releases different toxic metal ions found in them into the air, and hence, analyzing trace amounts of metals in tobacco smoking products is becoming more critical. The proposed research aims to evaluate the current levels of 11 heavy metals (namely, As, Pb, Cd, Co, Cr, Be, Ba, Mn, Ni, Fe, and Hg) in 22 tobacco products available in Egypt and Oman using inductively coupled plasma optical emission spectroscopy and a direct mercury analyzer. Although some elements such as Be, Co, and Cd were absent, the positive detection of As and Pb and the levels of Ba, Cr, and Ni are still alarming, especially for heavy smokers. The obtained results were then statistically related to previously published data in 2017 to explore the effectiveness of implementing the FCTC protocols within the Egyptian market. The outcomes suggested a positive impact of FCTC protocol implementation in Egypt, besides the lower levels of elemental content for Omani products compared to the Egyptian market.

10.
Sci Rep ; 14(1): 6361, 2024 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493177

RESUMO

Loratadine (LoR) is a highly lipophilic and practically insoluble in water, hence having a low oral bioavailability. As it is formulated as topical gel, it competitively binds with the receptors, thus reducing the side-effects. The objective of this study was to prepare LoR loaded nanosponge (LoR-NS) in gel for topical delivery. Nine different formulations of emulsion were prepared by solvent evaporation method with polyvinyl alcohol (PVA), ethyl cellulose (EC), and dichloromethane (DCM). Based on 32 Full Factorial Design (FFD), optimization was carried out by varying the concentration of LOR:EC ratio and stirring rate. The preparations were subjected for the evaluation of particle size (PS), in vitro release, zeta potential (ZP) and entrapment efficiency (EE). The results revealed that the NS dispersion was nanosized with sustained release profiles and significant PS. The optimised formulation was formulated and incorporated into carbopol 934P hydrogel. The formulation was then examined to surface morphological characterizations using scanning electron microscopy (SEM) which depicted spherical NS. Stability studies, undertaken for 2 months at 40 ± 2 °C/75 ± 5% RH, concluded to the stability of the formulation. The formulation did not cause skin irritation. Therefore, the prepared NS hydrogel proved to be a promising applicant for LoR as a novel drug delivery system (NDDS) for safe, sustained and controlled topical application.


Assuntos
Hidrogéis , Loratadina , Tamanho da Partícula
11.
Appl Spectrosc ; 78(3): 329-339, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38166449

RESUMO

Terbium- and nitrogen-doped carbon quantum dots (Tb,N@CQDs) were greenly created employing microwave synthesis from plum juice with terbium nitrate. The synthesis of Tb,N@CQDs was fast (7 min) with a high quantum yield (35.44%). Tb,N@CQDs were fully characterized using transmission electron microscopy, Zeta potential analysis, fluorescence, and ultraviolet spectroscopy. Omadacycline (OMC) is a broad-spectrum tetracycline that has been recently approved by the United States Food and Drug Act (FDA) in October 2018. OMC is the first oral aminomethylcycline class antibiotic drug that was authorized for the treatment of acute skin structure infections and community-acquired pneumonia. Tb,N@CQDs exhibited emission at 440 nm after excitation at 360 nm, where their fluorescence intensity showed a reduction upon addition of OMC. The experimental parameters were further studied and optimized. The linear range was between 40 and 60 parts per billion (ppb), with (limit of quantitation) equal to 34.78 ppb. The proposed approach was validated for bioanalytical purposes using FDA guidelines and proved to be straightforward, cheap, highly sensitive, and very selective, which can be used in clinical studies. The developed approach proved to be green using some current assessment metrics and was applied successfully for the determination of OMC in human plasma, milk, and pharmaceutical formulations as well as pharmacokinetic study.


Assuntos
Pontos Quânticos , Humanos , Pontos Quânticos/química , Térbio/química , Tetraciclinas , Carbono/química , Nitrogênio
12.
Cell Rep ; 42(8): 112960, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37556322

RESUMO

The small ubiquitin-like modifier (SUMO) protease SENP6 disassembles SUMO chains from cellular substrate proteins. We use a proteomic method to identify putative SENP6 substrates based on increased apparent molecular weight after SENP6 depletion. Proteins of the lamin family of intermediate filaments show substantially increased SUMO modification after SENP6 depletion. This is accompanied by nuclear structural changes remarkably like those associated with laminopathies. Two SUMO attachment sites on lamin A/C are close to sites of mutations in Emery-Driefuss and limb girdle muscular dystrophy. To establish a direct link between lamin SUMOylation and the observed phenotype, we developed proximity-induced SUMO modification (PISM), which fuses a lamin A/C targeting DARPin to a SUMO E3 ligase domain. This directly targets lamin A/C for SUMO conjugation and demonstrates that enhanced lamin SUMO modification recapitulates the altered nuclear structure manifest after SENP6 depletion. This shows SENP6 activity protects the nucleus against hyperSUMOylation-induced laminopathy-like alterations.


Assuntos
Lamina Tipo A , Peptídeo Hidrolases , Lamina Tipo A/metabolismo , Peptídeo Hidrolases/metabolismo , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Ubiquitina/metabolismo , Cisteína Endopeptidases/metabolismo , Proteômica , Sumoilação
13.
Anal Bioanal Chem ; 415(22): 5529-5538, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37432444

RESUMO

Copper (Cu) plays a role in maintaining healthy nerve cells and the immune system. Osteoporosis is a high-risk factor for Cu deficiency. In the proposed research, unique green, fluorescent cysteine-doped MnO2 quantum dots (Cys@MnO2 QDs) were synthesized and assessed for the determination of Cu in different food and hair samples. The developed quantum dots were synthesized with the help of cysteine using a straightforward ultrasonic approach to create 3D fluorescent Cys@MnO2 QDs. The resulting QDs' morphological and optical characteristics were carefully characterized. By adding Cu ions, the intensity of fluorescence for the produced Cys@MnO2 QDs was found to be dramatically reduced. Additionally, the applicability of Cys@MnO2 QDs as a new luminous nanoprobe was found to be strengthened by the quenching effect grounded on the Cu-S bonding. The concentrations of Cu2+ ions were estimated within the range of 0.06 to 7.00 µg mL-1, with limit of quantitation equal to 33.33 ng mL-1 and detection limit equal to 10.97 ng mL-1. The Cys@MnO2 QD technique was applied successfully for the quantification of Cu in a variety of foods, including chicken meat, turkey, and tinned fish, as well as in human hair samples. The chance that this novel technique could be a useful tool for figuring out the amount of cysteine in bio-samples is increased by the sensing system's remarkable advantages, which include being rapid, simple, and economical.


Assuntos
Pontos Quânticos , Cobre/química , Pontos Quânticos/química , Cisteína/química , Espectrometria de Fluorescência/métodos , Fatores de Tempo
14.
Medicina (Kaunas) ; 59(7)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37512045

RESUMO

Background: LGR5 is one of the most important stem cell markers for colorectal cancer (CRC), as it potentiates Wnt/Β-catenin signaling. The well-characterized deregulation of Wnt/Β-catenin signaling that occurs during adenoma/carcinoma sequence in CRC renders LGR5 a hopeful therapeutic target. We assessed the immunohistochemical expression of LGR5 and Β-catenin in normal colonic and tumorous lesions with a clinicopathological correlation. Methods: Tissue blocks and clinical data of 50 selected cases were included: 8 from normal mucosa, 12 cases of adenoma, and 30 cases of CRC, where sections were cut and re-examined and the immunohistochemical technique was conducted using anti-LGR5 and anti-Β-catenin to measure the staining density. Results: There was no expression of LGR5 in normal mucosa compared to samples of adenoma and CRC samples. The association analysis showed that CRC specimens were more likely to have strong LGR5 and Β-catenin expressions than the other two groups (p = 0.048 and p < 0.001, respectively). Specimens with high-grade dysplastic adenoma were more likely to express moderate-to-strong expression of LGR5 and Β-catenin (p = 0.013 and p = 0.036, respectively). In contrast, there were no statistically significant associations between LGR5 and Β-catenin expression with grade and stage. Conclusion: These results suggest and support the possible role of LGR5 as a potential marker of cancer stem cells in sporadic colorectal carcinogenesis in addition to a prognostic value for LGR5 and Β-catenin in adenomatous lesions according to immunohistochemical expression density. A potential therapeutic role of LGR5 in CRC is suggested for future studies based on its role in pathogenesis.


Assuntos
Adenoma , Neoplasias Colorretais , Humanos , Adenoma/patologia , Cateninas/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia
15.
Molecules ; 28(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37513344

RESUMO

Plaque psoriasis is a common, long-lasting illness that affects the immune system and causes significant negative impacts on a patient's physical health, well-being, and ability to work effectively. Deucravacitinib (DEU) is the first oral medication used in the treatment of plaque psoriasis, a chronic skin condition that causes red, scaly patches on the skin. DEU is a type of medication called an oral Janus kinase (JAK) inhibitor, which works by blocking specific enzymes that play a role in the inflammation and immune response associated with psoriasis. Therefore, a quick, easy, novel, reliable, sensitive, and straightforward liquid chromatography-tandem mass spectrometry (LC-MS/MS) approach was used to analyze DEU in plasma samples. The LC-MS/MS method for the determination of DEU in human plasma was based on using trimethoprim as an internal standard (IS). The separation of DEU and IS was carried out via liquid-liquid extraction (LLE). The extract was then subjected to the chromatographic system separation using the ACE-C18 column (4.6 × 100 mm, 5 µm). The mobile phase employed consisted of methanol and a solution of 2 mM ammonium formate (80:20 v/v, respectively). The flow rate used was set at 0.9 mL min-1. The creative strategy was performed by running an ABSCIEX API 4000 mass spectrometer with an electron spray ionization source in multiple reaction monitoring (MRM) mode. The ion transitions m/z 426.3 → 358.2 were used for DEU quantitation, while the ion transitions m/z 291.1 → 261.1 were used for trimethoprim quantitation. The accuracy, precision, linearity, recovery, and selectivity of DEU were deemed acceptable when validated for a concentration range between 0.500 and 601.050 ng/mL, utilizing a weighting factor of 1/x2.


Assuntos
Psoríase , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Reprodutibilidade dos Testes
16.
J Chromatogr A ; 1706: 464214, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37506464

RESUMO

For decades now, the separation of chiral enantiomers of drugs has been gaining the interest and attention of researchers. In 1991, the first guidelines for development of chiral drugs were firstly released by the US-FDA. Since then, the development in chromatographic enantioseparation tools has been fast and variable, aiming at creating a suitable environment where the physically and chemically identical enantiomers can be separated. Among those tools, the immobilization of chiral selectors (CS) on different stationary phases and the chiral mobile phase additives (CMPA) which have been progressed and studied extensively. This review article highlights the major advances in immobilization of CS together with their different recognition mechanisms as well as CMPA as a cheaper and successful alternative for chiral stationary phases. Moreover, the role of molecular modeling tool as a pre-step in the choice of CS for evaluating possible interactions with different ligands has been pointed up. Illustrations of reported methods and updates for immobilized CS and CMPA have been included.


Assuntos
Cromatografia Líquida de Alta Pressão , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Estereoisomerismo , Ligantes
17.
Electrophoresis ; 44(13-14): 1114-1142, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37043774

RESUMO

The process of choosing the most proper technique for studying the molecular interactions is based on critical factors such as instrumentation complexity, automation, experimental procedures, analysis time, consumables, and cost-value. This review has tracked the use of affinity capillary electrophoresis (ACE) and microscale thermophoresis (MST) techniques in the evaluation of molecular binding among different molecules during the 5 years 2016-2021. ACE has proved to be an attractive technique for biomolecular characterization with high resolution efficiency where small variations in several controlling factors can much improve such efficiency compared to other analytical techniques. Meanwhile, MST has proved its higher sensitivity for smaller amounts of complex non-purified biosamples without affecting its robustness while providing high through output. However, the main motivation to review both techniques in the proposed review was their capability to carry out all experiments without the need for immobilizing one interacting partner, besides a great flexibility in the use of buffering systems. The proposed review demonstrates the importance of both techniques in different areas of life sciences. Moreover, the recent advances in exploiting ACE and MST in other research interests have been discussed.


Assuntos
Eletroforese Capilar , Eletroforese Capilar/métodos , Ligação Proteica
18.
Arch Pharm (Weinheim) ; 356(6): e2300005, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37010439

RESUMO

The endemicity of the pandemic coronavirus disease 2019 (COVID-19) infection proved to be transitional only. Spikes are forming again in 2023, and high expectations are returning for reinfections and viral mutations. Molnupiravir (MOL) has been approved as an oral antiviral drug for the treatment of the COVID-19 causative virion. Therefore, the development of an ultrasensitive, instantaneous, and cost-effective method for the quantification of MOL in real plasma samples and formulated dosage form are mandatory. The proposed approach is based on the synthesis of a MOL metal-chelation product. MOL as a ligand was chelated with 1.0 mM zinc(II) in an acetate buffer (pH 5.3). After illumination at 340 nm, the intensity of the MOL fluorescence measured at 386 nm was increased by about 10-fold. The linearity range was found to be from 60.0 to 800.0 ng mL-1 with limit of quantitation (LOQ) of 28.6 ng mL-1 . Two methods were utilized for measuring the greenness of the proposed method (Green Analytical Procedure Index [GAPI] and analytical greenness metric [AGREE] methods), with results equal to 0.8. The binding stoichiometry of MOL with the zinc(II) ion was found to be 2:1. All the experimental parameters were optimized and validated using International Conference on Harmonization (ICH) and United States Food and Drug Administration (US-FDA) recommendations. Furthermore, the fluorescent probes were successfully utilized in real human plasma with high percentages of recovery (95.6%-97.1%) without any matrix interferences. The mechanism of fluorescent complex formation was confirmed using 1 H NMR in the presence and absence of Zn(II). The method was further utilized for testing content uniformity of MOL in its marketed capsule dosage forms.


Assuntos
COVID-19 , Zinco , Humanos , Espectrometria de Fluorescência/métodos , Relação Estrutura-Atividade , Preparações Farmacêuticas
19.
Toxics ; 11(3)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36977037

RESUMO

The tendency of using weight loss herbal preparations is continuously increasing, especially for the widespread consumption of junk food that is characterized by high calories. Weight loss herbal preparations are considered a type of food supplement product, and, as such, the regulations governing their quality control might be minimal. These products could be locally formulated in any country or internationally imported. Being non-controlled products, the herbal weight-loss products may contain high levels of elemental impurities that might exceed the permissible ranges. Moreover, these products contribute to the total daily intake (TDI) of such elements, which might represent concerns about their potential toxicological danger. In this research, the elemental contents in such products were investigated. The inductively coupled plasma with optical emission spectrometer (ICP-OES) was used to determine the levels of 15 elemental contents, namely, Na, K, Ca, Mg, Al, Cu, Fe, Li, Mn, As, Co, Cr, Cd, Ni and Pb. The results showed that seven micro-elements, namely Cd, Co, Ni, Cr, Pb, Li and Cu, were either not detectable or at a concentration much lower than their tolerable limits. However, all studied macro-elements (Na, K, Ca and Mg), together with Fe, were found at considerable, yet safe levels. On the other hand, Mn, Al and As contents showed perturbing levels in some of the studied products. Finally, a conclusion was highlighted for the necessity for stricter surveillance of such herbal products.

20.
Molecules ; 28(5)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36903432

RESUMO

Four eco-friendly, cost-effective, and fast stability-indicating UV-VIS spectrophotometric methods were validated for cefotaxime sodium (CFX) determination either in the presence of its acidic or alkaline degradation products. The applied methods used multivariate chemometry, namely, classical least square (CLS), principal component regression (PCR), partial least square (PLS), and genetic algorithm-partial least square (GA-PLS), to resolve the analytes' spectral overlap. The spectral zone for the studied mixtures was within the range from 220 to 320 nm at a 1 nm interval. The selected region showed severe overlap in the UV spectra of cefotaxime sodium and its acidic or alkaline degradation products. Seventeen mixtures were used for the models' construction, and eight were used as an external validation set. For the PLS and GA-PLS models, a number of latent factors were determined as a pre-step before the models' construction and found to be three for the (CFX/acidic degradants) mixture and two for the (CFX/alkaline degradants) mixture. For GA-PLS, spectral points were minimized to around 45% of the PLS models. The root mean square errors of prediction were found to be (0.19, 0.29, 0.47, and 0.20) for the (CFX/acidic degradants) mixture and (0.21, 0.21, 0.21, and 0.22) for the (CFX/alkaline degradants) mixture for CLS, PCR, PLS, and GA-PLS, respectively, indicating the excellent accuracy and precision of the developed models. The linear concentration range was studied within 12-20 µg mL-1 for CFX in both mixtures. The validity of the developed models was also judged using other different calculated tools such as root mean square error of cross validation, percentage recoveries, standard deviations, and correlation coefficients, which indicated excellent results. The developed methods were also applied to the determination of cefotaxime sodium in marketed vials, with satisfactory results. The results were statistically compared to the reported method, revealing no significant differences. Furthermore, the greenness profiles of the proposed methods were assessed using the GAPI and AGREE metrics.


Assuntos
Cefotaxima , Quimiometria , Espectrofotometria/métodos , Análise dos Mínimos Quadrados
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