Combinatorial Synthesis and High-Throughput Screening of Alkyl Amines for Nonviral Gene Delivery

Efficient delivery of plasmid DNA and siRNA into cells is essential for biological and biomedical research. Although significant efforts have been made to develop efficient nonviral vectors, such as cationic lipids and polymers, most of the vectors require multistep synthesis, which complicates both fast structural optimizations and combinatorial synthesis of such vectors. Here, we present a facile, single-step method based on an alkylation of amines, allowing for the fast parallel synthesis of libraries of cationic lipid-like molecules (lipidoids). We exploited the method to synthesize 200 lipidoids, which were screened for their transfection efficiency in HEK293T cells. The screen resulted in about 2% of new lipidoids capable of efficient cell transfection similar or higher than the efficiency of Lipofectamine 2000. In addition, we observed an enhancement of cellular transfection by combining single- with double-chain lipidoids, which was attributed to the different roles of the single- and double-tailed lipids in the mixed liposomes

Single-Tailed Lipidoids Enhance the Transfection Activity of Their Double-Tailed Counterparts

Cationic lipid-like molecules (lipidoids) are widely used for in vitro and in vivo gene delivery. Nearly all lipidoids developed to date employ double-tail or multiple-tail structures for transfection. Single-tail lipidoids are seldom considered for transfection as they have low efficiency in gene delivery. So far, there is no detailed study on the contribution to transfection efficiency of single-tail lipidoids when combined with standard double-tail lipidoids. Here, we use combinatorial chemistry to synthesize 17 double-tail and 17 single-tail lipidoids using thiol–yne and thiol–ene click chemistry, respectively. HEK 293T cells were used to analyze transfection efficiency by fluorescence microscopy and calculated based on the percentage of cells transfected. The size and zeta potential of liposomes and lipoplexes were characterized by dynamic light scattering (DLS). Intracellular DNA delivery and trafficking was further examined using confocal microscopy. Our study shows that combining single with double-tail lipidoids increases uptake of lipoplexes, as well as cellular transfection efficiency

Utilizing Lubricant Loss from Omniphobic Coatings as a Multifunctional Delivery Mechanism

Silicon-based lubricant-infused surfaces (LIS) have revolutionized the surface and interface science field with their omniphobic properties. Polydimethylsiloxane (PDMS) LIS have demonstrated excellent potential for many biological, food, or cosmetic applications. However, translation into industry faces limitations for synthesis methodologies, reagent expense, retention of omniphobicity, and legislature concerning lubricant migration. Preventing lubricant loss and retention of omniphobicity has been widely investigated, but what if the gradual lubricant depletion could be utilized for releasing active agents? Herein, we produce silicone-based organogel LIS via spontaneous 1-step polyurea reactions (Silgels) and functionalize with silver nanoparticles (Ag NP). We comparatively examined their physicochemical properties, omniphobic dewetting for probe liquids and complex mixtures (foodstuffs), and biocompatibility with mammalian and bacterial cultures. Overall, we present an easily scalable methodology to produce multifunctional, biocompatible LIS that has potential for the food packaging, cosmetic, and biological industries

Reactive Superhydrophobic Surface and Its Photoinduced Disulfide-ene and Thiol-ene (Bio)functionalization

Reactive superhydrophobic surfaces are highly promising for biotechnological, analytical, sensor, or diagnostic applications but are difficult to realize due to their chemical inertness. In this communication, we report on a photoactive, inscribable, nonwettable, and transparent surface (PAINTS), prepared by polycondensation of trichlorovinylsilane to form thin transparent reactive porous nanofilament on a solid substrate. The PAINTS shows superhydrophobicity and can be conveniently functionalized with the photoclick thiol-ene reaction. In addition, we show for the first time that the PAINTS bearing vinyl groups can be easily modified with disulfides under UV irradiation. The effect of superhydrophobicity of PAINTS on the formation of high-resolution surface patterns has been investigated. The developed reactive superhydrophobic coating can find applications for surface biofunctionalization using abundant thiol or disulfide bearing biomolecules, such as peptides, proteins, or antibodies

Slippery Liquid-Attached Surface for Robust Biofouling Resistance

Materials for biodevices and bioimplants commonly suffer from unwanted but unavoidable biofouling problems due to the nonspecific adhesion of proteins, cells, or bacteria. Chemical coating or physical strategies for reducing biofouling have been pursued, yet highly robust antibiofouling surfaces that can persistently resist contamination in biological environments are still lacking. In this study, we developed a facile method to fabricate a highly robust slippery and antibiofouling surface by conjugating a liquid-like polymer layer to a substrate. This slippery liquid-attached (SLA) surface was created via a one-step equilibration reaction by tethering methoxy-terminated polydimethylsiloxane (PDMS-OCH3) polymer brushes onto a substrate to form a transparent “liquid-like” layer. The SLA surface exhibited excellent sliding behaviors toward a wide range of liquids and small particles and antibiofouling properties against the long-term adhesion of small biomolecules, proteins, cells, and bacteria. Moreover, in contrast to superomniphobic surfaces and liquid-infused porous surfaces (SLIPS) requiring micro/nanostructures, the SLA layer could be obtained on smooth surfaces and maintain its biofouling resistance under abrasion with persistent stability. Our study offers a simple method to functionalize surfaces with robust slippery and antibiofouling properties, which is promising for potential applications including medical implants and biodevices

Machine Learning-Assisted Sensor Array Based on Poly(amidoamine) (PAMAM) Dendrimers for Diagnosing Alzheimer’s Disease

Alzheimer’s disease (AD) is the most prevalent neurodegenerative disorder, and the early diagnosis of AD remains challenging. Here we have developed a fluorescent sensor array composed of three modified polyamidoamine dendrimers. Proteins of various properties were differentiated via this array with 100% accuracy, proving the rationality of the array’s design. The mechanism of the fluorescence response was discussed. Furthermore, the robust three-element array enables parallel detection of multiple Aβ40/Aβ42 aggregates (0.5 μM) in diverse interferents, serum media, and cerebrospinal fluid (CSF) with high accuracy, through machine learning algorithms, demonstrating the tremendous potential of the sensor array in Alzheimer’s disease diagnosis

One-Component Multichannel Sensor Array for Rapid Identification of Bacteria

Bacterial infections routinely cause serious problems to public health. To mitigate the impact of bacterial infections, sensing systems are urgently required for the detection and subsequent epidemiological control of pathogenic organisms. Most conventional approaches are time-consuming and highly instrument- and professional operator-dependent. Here, we developed a novel one-component multichannel array constructed with complex systems made from three modified polyethyleneimine as well as negatively charged graphene oxide, which provided an information-rich multimode response to successfully identify 10 bacteria within minutes via electrostatic interactions and hydrophobic interactions. Furthermore, the concentration of bacteria (from OD600 = 0.025 to 1) and the ratio of mixed bacteria were successfully achieved with our smart sensing system. Our designed sensor array also exhibited huge potential in biological samples, such as in urine (OD600 = 0.125, 94% accuracy). The way to construct a sensor array with minimal sensor element with abundant signal outputs tremendously saves cost and time, providing a powerful tool for the diagnosis and assessment of bacterial infections in the clinic

Injectable Slippery Lubricant-Coated Spiky Microparticles with Persistent and Exceptional Biofouling-Resistance

Injectable micron-sized particles have historically achieved promising applications, but they continued to suffer from long-term biofouling caused by the adhesions of biomolecules, cells, and bacteria. Recently, a slippery lubricant infusion porous substrate (SLIPS) exhibited robust antiadhesiveness against many liquids; however, they were constructed using a 2D substrate, and they were not suitable for in vivo applications, such as injectable biomaterials. Inspired by SLIPS, here, we report the first case of injectable solid microparticles coated with a lubricating liquid surface to continuously resist biofouling. In our design, microparticles were attached with nanospikes and fluorinated to entrap the lubricant. The nanospikes enabled the lubricant-coated spiky microparticles (LCSMPs) to anomalously disperse in water despite the attraction between the surfaces of the microparticles. This result indicated that the LCSMPs exhibited persistent anomalous dispersity in water while maintaining a robust lubricating surface layer. LCSMPs prevented the adhesion of proteins, mammalian cells, and bacteria, including Escherichia coli and Staphylococcus aureus. LCSMPs also reduced in vivo fibrosis while conventional microparticles were heavily biofouled. This technology introduced a new class of injectable anti-biofouling microparticles with reduced risks of inflammation and infections

Additional file 2 of The repertoire of testicular extracellular vesicle cargoes and their involvement in inter-compartmental communication associated with spermatogenesis

Additional file 2: Table S1. List of proteins identified in testicular EVs

Additional file 4 of The repertoire of testicular extracellular vesicle cargoes and their involvement in inter-compartmental communication associated with spermatogenesis

Additional file 4: Table S3. List of small RNAs identified in testicular EVs