New piperidinium surfactants with carbamate fragments as effective adjuvants in insecticide compositions based on imidacloprid.

Background: Surfactants, particularly non-ionic ones, are widely used as adjuvants in pesticide formulations due to their ability to maintain pesticide effectiveness without changing solution properties, such as pH. While non-ionic surfactants are generally low-toxic, stable, and excellent dispersants with high solubilization capabilities, they may be less effective than cationic surfactants, which offer superior surface activity, transport properties, and antimicrobial action. This study investigates the efficacy of new piperidinium surfactants with carbamate fragments as adjuvants in insecticide formulations containing imidacloprid.

Piperidinium surfactants functionalized with carbamate fragment: Aggregation, antimicrobial activity and cytotoxicity.

The biomimetic nature of supramolecular systems, the structural similarity of synthetic surfactants to biomolecules (lipids, proteins), provide them with high membranotropy, the ability to overcome biological barriers, and affinity towards biosubstances. Despite rather high toxicity cationic surfactants are of importance as antimicrobial agents, gene nanocarriers and mitochondria targeted ligands. To minimize this limitation, cationic amphiphilic matrix undergoes modification with various functional groups.

Can Activation of Acetylcholinesterase by β-Amyloid Peptide Decrease the Effectiveness of Cholinesterase Inhibitors?

A central event in the pathogenesis of Alzheimer's disease (AD) is the accumulation of senile plaques composed of aggregated amyloid-β (Aβ) peptides. The main class of drugs currently used for the treatment of AD are the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors. In this study, it has been shown that Aβ augmented AChE activity in vitro, maximum activation of 548 ± 5% was achieved following 48 h of incubation with 10 μM of Aβ, leading to a 7.

Dynamic light scattering and transmission electron microscopy in drug delivery: a roadmap for correct characterization of nanoparticles and interpretation of results.

In this focus article, we provide a scrutinizing analysis of transmission electron microscopy (TEM) and dynamic light scattering (DLS) as the two common methods to study the sizes of nanoparticles with focus on the application in pharmaceutics and drug delivery. Control over the size and shape of nanoparticles is one of the key factors for many biomedical systems. Particle size will substantially affect their permeation through biological membranes.

Role of Polyanions and Surfactant Head Group in the Formation of Polymer-Colloid Nanocontainers.

Objectives: This study was aimed at the investigation of the supramolecular systems based on cationic surfactants bearing cyclic head groups (imidazolium and pyrrolidinium) and polyanions (polyacrylic acid (PAA) and human serum albumin (HSA)), and factors governing their structural behavior to create functional nanosystems with controlled properties. Research hypothesis. Mixed PE-surfactant complexes based on oppositely charged species are characterized by multifactor behavior strongly affected by the nature of both components.

Therapy of Organophosphate Poisoning via Intranasal Administration of 2-PAM-Loaded Chitosomes.

Chitosan-decorated liposomes were proposed for the first time for the intranasal delivery of acetylcholinesterase (AChE) reactivator pralidoxime chloride (2-PAM) to the brain as a therapy for organophosphorus compounds (OPs) poisoning. Firstly, the chitosome composition based on phospholipids, cholesterol, chitosans (Cs) of different molecular weights, and its arginine derivative was developed and optimized. The use of the polymer modification led to an increase in the encapsulation efficiency toward rhodamine B (RhB; ~85%) and 2-PAM (~60%) by 20% compared to conventional liposomes.

Enhancement of the Transdermal Delivery of Nonsteroidal Anti-inflammatory Drugs Using Liposomes Containing Cationic Surfactants.

New hybrid liposomes based on cationic amphiphiles with different structures of the head group (cetyltrimethylammonium bromide (CTAB), 3-hexadecyl-1-hydroxyethylimidazolium bromide (IA-16(OH)), 1-(butylcarbamoyl)oxyethyl-3-hexadecylimidazolium bromide (IAC 16(Bu)), and hexadecylmethylpyrrolidinium bromide (PR-16)) were developed for transdermal administration of nonsteroidal anti-inflammatory drugs. The different surfactant/lipid compositions were studied to obtain stable liposomes with high functionality. The hydrodynamic diameter of cationic liposomes was ∼110 nm.

Cationic Imidazolium Amphiphiles Bearing a Methoxyphenyl Fragment: Synthesis, Self-Assembly Behavior, and Antimicrobial Activity.

Novel cationic amphiphiles of the 3-alkyl-1-(4-methoxyphenyl)-1-imidazol-3-ium bromide series bearing methoxyphenyl fragments (MPI-) have been synthesized. Their aggregation properties in aqueous solutions, solubilization capacity, and hemolytic and antimicrobial activities have been investigated by a number of physicochemical methods. Using tensiometry, conductometry, and fluorescence spectroscopy, it was shown that the MPI- have lower CMCs than their nonfunctionalized counterparts.

Self-Assembling Metallocomplexes of the Amphiphilic 1,4-Diazabicyclo[2.2.2]octane Derivative as a Platform for the Development of Nonplatinum Anticancer Drugs.

New 1-cetyl-4-aza-1-azoniabicyclo[2.2.2]octane bromide complexes with copper(II) bromide and lanthanum(III) nitrate were characterized using dynamic light scattering and transmission electron microscopy, with self-assembly and the morphological behavior elucidated.

Antimicrobial Properties and Cytotoxic Effect of Imidazolium Geminis with Tunable Hydrophobicity.

Antimicrobial, membranotropic and cytotoxic properties of dicationic imidazolium surfactants of n-s-n (Im) series with variable length of alkyl group (n = 8, 10, 12, 14, 16) and spacer fragment (s = 2, 3, 4) were explored and compared with monocationic analogues. Their activity against a representative range of Gram-positive and Gram-negative bacteria, and also fungi, is characterized. The relationship between the biological activity and the structural features of these compounds is revealed, with the hydrophobicity emphasized as a key factor.

Cationic liposomes mediated transdermal delivery of meloxicam and ketoprofen: Optimization of the composition, in vitro and in vivo assessment of efficiency.

New liposomes modified with pyrrolidinium surfactants containing a hydroxyethyl fragment (CPB, n = 12, 14, 16) were prepared for transdermal delivery of non-steroidal anti-inflammatory drugs. In order to obtain the optimal composition, the surfactant/lipid molar ratio (0.02/1; 0.

Mitochondria-targeted mesoporous silica nanoparticles noncovalently modified with triphenylphosphonium cation: Physicochemical characteristics, cytotoxicity and intracellular uptake.

Novel nanocomposite system based on mesoporous silica nanoparticles (MSNs) noncovalently modified with hexadecyltriphenylphosphonium bromide (HTPPB) has been prepared, thoroughly characterized and used for encapsulation of model cargo Rhodamine B (RhB). The high encapsulation efficacy of this dye by HTPPB-modified mesoporous particles was demonstrated by spectrophotometry and thermography techniques. The bioavailability of MSN@HTPPB was testified.

Polymer-Colloid Complexes Based on Cationic Imidazolium Amphiphile, Polyacrylic Acid and DNA Decamer.

The solution behavior and physicochemical characteristics of polymer-colloid complexes based on cationic imidazolium amphiphile with a dodecyl tail (IA-12) and polyacrylic acid (PAA) or DNA decamer (oligonucleotide) were evaluated using tensiometry, conductometry, dynamic and electrophoretic light scattering and fluorescent spectroscopy and microscopy. It has been established that PAA addition to the surfactant system resulted in a ca. 200-fold decrease in the aggregation threshold of IA-12, with the hydrodynamic diameter of complexes ranging within 100-150 nm.

Biomedical potentialities of cationic geminis as modulating agents of liposome in drug delivery across biological barriers and cellular uptake.

Hydroxyethyl bearing gemini surfactants, alkanediyl-α,ω-bis(N-hexadecyl-N-2-hydroxyethyl-N-methylammonium bromide), 16-s-16(OH), were used to augment phosphatidylcholine based liposomes to achieve higher stability and enhanced cellular uptake and penetration. The developed liposomes were loaded with rhodamine B, doxorubicin hydrochloride, pralidoxime chloride to investigate release properties, cytotoxicity in vitro, as well as ability to cross the blood-brain barrier. At molar ratio of 35:1 (lipid:surfactant) the formulation was found to be of low toxicity, stable for two months, and able to deliver rhodamine B beyond the blood-brain barrier in rats.

Bi-functional sterically hindered phenol lipid-based delivery systems as potential multi-target agents against Alzheimer's disease via an intranasal route.

New lipid-based nanomaterials and multi-target directed ligands (MTDLs) based on sterically hindered phenol, containing a quaternary ammonium moiety (SHP-s-R, with s = 2,3) of varying hydrophobicity (R = CH2Ph and CnH2n+1, with n = 8, 10, 12, 16), have been prepared as potential drugs against Alzheimer's disease (AD). SHP-s-R are inhibitors of human cholinesterases with antioxidant properties. The inhibitory potency of SHP-s-R and selectivity ratio of cholinesterase inhibition were found to significantly depend on the length of the methylene spacer (s) and alkyl chain length.

Design and synthesis of amphiphilic 2-hydroxybenzylphosphonium salts with antimicrobial and antitumor dual action.

Here we report the synthesis and biological evaluation of a series of new 2-hydroxybenzylphosphonium salts (QPS) with antimicrobial and antitumor dual action. The most active compounds exhibit antimicrobial activity at a micromolar level against Gram-positive bacteria Sa (ATCC 209p and clinical isolates), Bc (1-2 μM) and fungi Tm and Ca, and induced no notable hemolysis at MIC. The change in nature of substituents of the same length led to a drastic change of biological activity.

Design of -Methyl-d-Glucamine-Based Resorcin[4]arene Nanoparticles for Enhanced Apoptosis Effects.

The addition of specific chemical groups in a macrocycle structure influences its functional properties and, consequently, can provide new possibilities, among which are aggregation properties, water solubility, biocompatibility, stimuli response, biological activity, etc. Herein, we report synthesis of new resorcin[4]arene with -methyl-d-glucamine groups on the upper rim and n-decyl chains on the lower rim, an investigation of its self-assembly behavior in aqueous media, and its use as a building block for the formation of drug nanocontainer. -methyl-d-glucamine fragments in the resorcin[4]arene structure promote higher stability in solutions, simplification of self-aggregation, and increased biological activity.

Cationic Surfactants: Self-Assembly, Structure-Activity Correlation and Their Biological Applications.

The development of biotechnological protocols based on cationic surfactants is a modern trend focusing on the fabrication of antimicrobial and bioimaging agents, supramolecular catalysts, stabilizers of nanoparticles, and especially drug and gene nanocarriers. The main emphasis given to the design of novel ecologically friendly and biocompatible cationic surfactants makes it possible to avoid the drawbacks of nanoformulations preventing their entry to clinical trials. To solve the problem of toxicity various ways are proposed, including the use of mixed composition with nontoxic nonionic surfactants and/or hydrotropic agents, design of amphiphilic compounds bearing natural or cleavable fragments.

Mitochondria-targeted cationic liposomes modified with alkyltriphenylphosphonium bromides loaded with hydrophilic drugs: preparation, cytotoxicity and colocalization assay.

The purpose of this work was to obtain cationic liposomes based on 1,2-dipalmitoyl-sn-glycero-3-phosphocholine noncovalently modified using alkyltriphenylphosphonium bromides (TPPB-n) with different lengths of hydrocarbon tail for targeted delivery to mitochondria. The hydrodynamic diameter and electrokinetic potential of hybrid liposomes depending on the lipid/surfactant ratio were monitored in time with the aim to optimize the composition with sufficient stability and positive charge for mitochondria-targeted delivery. It was found that increasing the alkyl tail length of the surfactant (up to TPPB-14) leads to an increase in the positive charge of the liposomes.

Self-assembled systems based on novel hydroxyethylated imidazolium-containing amphiphiles: Interaction with DNA decamer, protein and lipid.

The study on aggregation capacity of novel imidazolium-containing amphiphiles of 1-(2-hydroxyethyl)alkylimidazolium bromide series and their interaction with bio-objects (DNA decamer, bovine serum albumin, phospholipid) was performed. It was revealed that introduction of hydroxyethyl moiety into the surfactant molecule resulted in 1.5-2-fold decrease of critical micelle concentration.

Alkyl triphenylphosphonium surfactants as nucleic acid carriers: complexation efficacy toward DNA decamers, interaction with lipid bilayers and cytotoxicity studies.

Herein, for the first time the complexation ability of a homological series of triphenylphosphonium surfactants (TPPB-n) toward DNA decamers has been explored. Formation of lipoplexes was confirmed by alternative techniques, including dynamic light scattering, indicating the occurrence of nanosized complexes (ca. 100-150 nm), and monitoring the charge neutralization of nucleotide phosphate groups and the fluorescence quenching of dye-intercalator ethidium bromide.

Novel hybrid liposomal formulations based on imidazolium-containing amphiphiles for drug encapsulation.

Novel liposomes based on 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and imidazolium-containing amphiphiles with various length of hydrophobic tail at various molar ratio of components have been fabricated. Obtained formulations were characterized using dynamic and electrophoretic light scattering as well as transmission electron microscopy techniques. It has been established, that DPPC liposomes modification by these cationic amphiphiles resulted in zeta potential increase from +3 mV to +45-70 mV and improve its stability for a long time (more than 6 months, whereas unmodified liposomes have been destructed after 2 weeks of storage).