Lipid 15 is an ionizable amino lipid used for the generation of Lipid nanoparticles .

An analog of SM-102. The ethanolamine amino lipid head enhances encapsulation of mRNA. The lipid has primary esters at C7 position relative to the amine nitrogen. The primary lipid tail has 8 carbon tail. The lipid can be used for mRNA-based therapies which depends on the availability of a safe and efficient delivery vehicle.

D-Lin-MC2-DMA(MC2) is a cationic lipid that has been synthesized for Lipid nanoparticles (LNPs) to deliver the siRNA.

D-Lin-MC4-DMA(MC4) is a cationic lipid that has been synthesized for Lipid nanoparticles (LNPs) to deliver the siRNA.

RCB-4-8​​ is a biodegradable ionizable lipid nanoparticle (LNP) engineered for efficient pulmonary mRNA delivery and in vivo genome editing, as detailed in the primary research article ​​"Combinatorial design of nanoparticles for pulmonary mRNA delivery and genome editing"​​ (Li et al., Nature Biotechnology 2023）. Synthesized from a combinatorial library of 720 biodegradable lipids via a three-component reaction system, RCB-4-8 features an alkyne-containing lipid tail and tertiary amine headgroup, optimized through high-throughput screening for superior lung-targeting capabilities. Its unique molecular design incorporates hydrolyzable ester and carbonate groups, enabling rapid biodegradation (<30% lung retention at 48 h vs. >90% for conventional lipids) while maintaining high transfection efficiency. When formulated with DOTAP instead of DOPE, RCB-4-8 LNPs achieved ​​100-fold higher luciferase mRNA expression​​ in murine lungs compared to FDA-approved MC3 LNPs and mediated ​​95% GFP knockout​​ in vitro. In Ai9 reporter mice, intratracheal delivery of RCB-4-8 loaded with Cre mRNA edited ​​53% of total lung cells​​ after three doses, while codelivery with Cas9 mRNA/sgRNA yielded ​​7.2% tdTomato⁺ cells​​, rising to ​​17%​​ when combined with AAV-sgRNAs. With an optimal particle size of ​​85.7 nm​​ (PDI 0.11) and ​​>87% mRNA encapsulation​​, RCB-4-8 supports repeat dosing and represents a transformative platform for inhalable gene therapies targeting congenital lung diseases like cystic fibrosis.

4A3-SC7​​ is a proprietary, ionizable lipid component central to the SORT LNP platform developed for targeted organ delivery. It features a unique ​​branched-tail structure​​ designed to enhance mRNA encapsulation and endosomal escape. In the study, it served as the ​​primary ionizable lipid​​ in both Liver SORT LNPs and updated Lung SORT LNPs. For liver targeting, it was formulated at ​​15.04 mol%​​ alongside helper lipids (DOPE: 23.04%, Cholesterol: 38.72%), PEG-lipid (DMG-PEG2000: 3.2%), and the liver-targeting lipid ​​4A3-Cit (20 mol%)​​. This specific composition (Total lipid:RNA = 20:1 wt/wt) yielded LNPs with ​​~74 nm size​​, ​​low PDI (0.17)​​, and ​​high encapsulation efficiency (87%)​​ for large mRNAs like ABE editors (~5000 nt). Its branched-tail architecture was critical for stabilizing nanoparticles encapsulating large RNAs, overcoming a key limitation of previous formulations. 4A3-SC7-based Liver SORT LNPs enabled ​​>40% base editing in hepatocytes​​ in vivo, achieving durable correction of the disease-causing SERPINA1 mutation in PiZ mice and significantly reducing pathological protein aggregates. In the updated DualSORT system, 4A3-SC7 was also paired with ​​DORI​​ (instead of DOTAP) for improved lung targeting, demonstrating its versatility as a foundational ionizable lipid for multi-organ gene editing therapeutics.

Acuitas Lipid III-2 is an ionizable amine lipid with two identical ester tails adjacent to C6 position relative to amine from patent:WO2017075531A1 with the similar activity as ALC-0315. The head of lipid is propanolamine which can effectively encapsulate mRNA used in gene therapies which depends on the availability of a safe and efficient delivery vehicle.

4A3-SCC-10 is a disulfide bond-containing biodegradable ionizable cationic lipid (pKa = 6.22) that has been used in the generation of lipid nanoparticles (LNPs) for the delivery of mRNA in vitro and in vivo. LNPs containing 4A3-SCC-10 and encapsulating a Cy5-RNA reporter have improved endosomal escape ability over Cy5-RNA-encapsulated LNPs containing 4A3-SC-10, which does not contain disulfide bonds, in HeLa cells. Intravenous administration of LNPs containing 4A3-SCC-10 and encapsulating an mRNA luciferase reporter selectively accumulate in mouse liver.

A fluorescent molecule-conjugated SM-102 derivative for tracking and locating the position of SM-102.

80-O18 is a lipidoid known for its exceptional ability to enhance overall cellular uptake, showcasing significant potential as an effective delivery agent.

​​C-a16​​ is an ionizable lipid engineered through Mannich reaction chemistry, designed to revolutionize mRNA delivery by synergizing high efficiency with minimized immune activation. Synthesized by reacting a phenolic tail derivative, formaldehyde, and a branched tertiary amine core under optimized ethanol conditions, this lipid integrates antioxidant phenol groups directly into its structure. These phenol moieties serve as intrinsic radical scavengers, effectively neutralizing intracellular reactive oxygen species that typically degrade mRNA and trigger inflammation.In lipid nanoparticle formulations, C-a16 constitutes the functional backbone, enabling superior mRNA encapsulation efficiency while maintaining a stable nanoparticle size of approximately 80–100 nm. Critically, it outperforms conventional lipids like DLin-MC3-DMA by achieving significantly higher target-protein expression in vivo alongside markedly reduced pro-inflammatory cytokine secretion. The antioxidant capability is not incidental but fundamental—quenching the phenol groups drastically diminishes both ROS suppression and delivery efficacy, confirming the design's mechanistic elegance.C-a16 represents a paradigm shift: its biomimetic antioxidant architecture addresses the chronic trade-off between delivery potency and immunogenicity, unlocking safer therapeutic applications for vaccines and gene therapies.

Lipid VII is a novel ionizable cationic lipid developed by Sanofi.Lipid VII demonstrates exceptional performance as a lipid nanoparticle delivery system, combining high efficiency with outstanding safety. Cellular assays reveal VII achieves 180,000 RLU transfection efficiency under serum conditions, surpassing traditional SS-OP systems by 2.25-fold while maintaining perfect 100% cellular viability and eliminating cytotoxicity risks that plague alternatives. In vivo systemic delivery shows rapid whole-body biodistribution, reaching photon emission levels exceeding 1.00E+10 photons/sec within 48 hours. VII exhibits superior organ targeting with a liver-specific accumulation ratio of 9.0, outperforming SS-OP systems by 50%, while reducing off-target spleen accumulation by 20%. Its versatility is further validated in therapeutic protein expression, where structural analogs achieve erythropoietin concentrations of 14 ng/mL, exceeding industry standards by 180%. For vaccine applications, VII generates a median HAI titer of 7,611 against H1N1 influenza—540 times higher than baseline buffers and more than double the next-best formulation. This evidence establishes VII as a breakthrough technology, offering unmatched efficiency, precision targeting, and clinical-grade safety across diverse applications.

SM-86 Analog-1 is a novel ionizable lipid designed to improve the delivery of RNA via lipid nanoparticles (LNPs) It is derived from SM-86,with 8 carbon within its hydrophobic tail.

L1 is a biodegradable, branched self-immolative lipid optimized for ​​high-efficiency mRNA delivery​​. Its disulfide-based architecture enables rapid glutathione-triggered degradation in the cytosol (liver half-life: 4.2 days), promoting rapid clearance while maintaining serum stability. In vivo, L1 achieves ​​exceptional mRNA translation​​, producing twice the hEPO protein levels of the clinically approved MC3 lipid at 0.1 mg/kg. Its apparent pKa (6.57) facilitates efficient endosomal escape without compromising safety: even at 5 mg/kg, L1 causes no significant body weight loss or sustained inflammation. Structural features (C7 alkyl tails, carbamate linker) balance potency and biodegradability, making L1 ideal for mRNA vaccines and protein-replacement therapies.

GVS-18-B6 is a silicon ether-based ionizable lipid developed by Genevant, optimized for mRNA-LNP delivery, characterized by a short-chain trialkyl structure with three C10 alkyl chains (including a cis double bond) and a dimethylamino (DMA) head group linked via a 4-carbon spacer (pKa ~6.15). Its LNP formulations exhibit a narrow particle size distribution (89 nm, PDI=0.06), high mRNA encapsulation efficiency (90%), and pH-dependent surface charge (−0.11 mV at pH 7.5 vs. +2.69 mV at pH 5.5), facilitating endosomal escape. ​​In vivo​​, GVS-18-B6 demonstrated superior liver-specific mRNA expression (5.30×10⁷ pg EGFP/g liver, 2.6× higher than MC3) with minimal spleen accumulation (liver/spleen ratio 92:1 vs. MC3’s 10:1), attributed to rapid non-enzymatic hydrolysis of its silicon ether bonds. This mechanism enables near-complete hepatic clearance within 6 hours in mice and 24 hours in NHPs, avoiding long-term organ retention (MC3 retained 25% in liver after 28 days). Compared to benchmarks (MC3, SM-102, LP-01), GVS-18-B6 showed enhanced potency in RBC hemolysis assays (pH 6.2), indicating earlier endosomal membrane disruption, and maintained stability through 12-month frozen storage or repeated freeze-thaw cycles. ​​Toxicity profiling​​ revealed minimal immunogenicity (MCP-1 levels 0.58×10⁶ vs. MC3’s 1.10×10⁶) and no ALT/AST elevation or anti-PEG antibody induction in NHPs after repeated dosing. Its species-agnostic clearance, low off-target effects, and high tolerability (6 mg/kg dose in mice) position GVS-18-B6 as a leading candidate for chronic disease therapies requiring frequent mRNA administration.

ADA (Acid-Degradable Anionic Lipids) is revolutionizing mRNA delivery with its unique azido-acetal linker, enabling rapid hydrolysis in endosomes (pH ~6.0). This breakthrough technology ensures efficient endosomal escape, significantly enhancing mRNA delivery to target cells. ADA-LNPs excel in delivering mRNA to the spleen and liver, making them ideal for immune-related therapies.By degrading into biocompatible byproducts, ADA minimizes long-term tissue persistence and toxicity.ADA-LNPs outperform traditional LNPs, delivering mRNA more effectively to immune cells like macrophages and B cells.

Acid-degradable Cationic Lipid (ADC) composed of cationic lipid is synthesized with the azido-acetal linker and used to generate RD-LNPs, which significantly improves the performance of LNP-mRNA complexes in vitro and in vivo.

Acuitas II-12 is an novel ionizable amine lipid used for mRNA delivery from Acuitas Therapeutics patent WO2016176330A1

Acuitas Lipid III-7 is an novel ionizable amine lipid used for mRNA delivery from Acuitas Therapeutics patent US 10,166,298 B2.

Lipid 29 analogue-3 is an ionizable lipid designed for the delivery of RNA-based therapeutics, such as mRNA or siRNA.

Iso-A11B5C1 is an ionizable lipid. The iso-A11B5C1 LNP demonstrates a high level of muscle-specific mRNA delivery efficiency. exhibiting transfection efficiency comparable to the commercially available lipid SM-102, while considerably reducing inadvertent mRNA expression in main organs such as the liver and spleen.Additionally, study results show that intramuscular administration of mRNA formulated with iso-A11B5C1 LNP caused potent cellular immune responses, even with limited expression observed in lymph nodes.

ND-O1 (SM-86 Analog-2) is a novel ionizable lipid designed to improve the delivery of siRNA via lipid nanoparticles (LNPs) for treating liver fibrosis. It is derived from SM-86 (structurally similar to SM-102, used in COVID-19 mRNA vaccines) but incorporates an ether bond within its hydrophobic tail, a first-of-its-kind modification aimed at enhancing delivery efficiency. In Vitro Efficiency: ND-O1 LNPs (LNP-O1) showed significantly higher siRNA transfection efficiency in activated fibroblasts compared to Lipid 5 LNPs (LNP-M). In Vivo Efficacy: In a CCl4-induced liver fibrosis mouse model, LNP-O1/siHSP47 (loaded with HSP47-targeting siRNA) reduced HSP47 expression by ~84%, threefold more effective than LNP-M. This led to a dramatic reduction in collagen deposition and marked improvement in liver fibrosis. Safety: The ether bond modification did not introduce additional toxicity, maintaining biocompatibility. ND-O1 represents a breakthrough in ionizable lipid design, demonstrating that strategic placement of ether bonds in hydrophobic tails can enhance LNP performance without compromising safety. Its success highlights its potential for clinical translation in RNA-based therapies for liver fibrosis and other hepatic diseases.

A4B4-S3 is a novel biodegradable ionizable lipid that has been meticulously designed through modular platforms and optimized specifically for mRNA delivery. It serves as a critical component of lipid nanoparticles (LNPs) and enhances mRNA delivery efficiency by facilitating endosomal escape. The structural design of A4B4-S3 leverages the Passerini reaction, a highly efficient and modular chemical method that enables the rapid generation of diverse lipid libraries. The design focuses on optimizing the methylene units between lipid headgroups and linkages to strengthen hydrogen bonding interactions with mRNA ribophosphate complexes. This enhanced hydrogen bonding allows for more effective release of mRNA from endosomes, thereby boosting delivery efficiency. Concurrently, the structural optimization improves biodegradability, reducing potential long-term toxicity risks. In experimental studies, A4B4-S3 has demonstrated superior gene editing efficacy in mouse liver compared to SM-102, a clinically prevalent lipid used in Moderna's COVID-19 vaccine. It also shows potential for repeat-dose protein replacement therapies, suggesting enhanced stability and safety for long-term treatment regimens. Technologically, A4B4-S3 not only provides a more efficient LNP formulation but also deepens the understanding of the relationship between structure and delivery efficiency. This offers new directions for the development of future mRNA therapeutics. In summary, A4B4-S3 represents a next-generation delivery carrier achieved through rational design and high-throughput screening strategies. Its performance enhancements and biodegradable properties position it as a promising candidate for gene therapies and vaccine applications.

The LUMI-6 lipid, autonomously designed via the LUMI-lab platform, is a brominated ionizable lipid optimized for mRNA delivery. Formulated at a molar ratio of 35:28:34.5:2 (LUMI-6:DOTAP:cholesterol:C14-PEG2000), LNPs exhibit uniform physicochemical properties, including a hydrodynamic diameter of ~80 nm, polydispersity index (PDI) <0.2, and robust mRNA encapsulation efficiency. In vitro, LUMI-6 LNPs demonstrated 1.8-fold higher transfection potency in human bronchial epithelial cells compared to its debrominated counterpart (LUMI-6D), with minimal cytotoxicity confirmed by CCK-8 assays. In vivo, pulmonary delivery of CRISPR-Cas9 mRNA via LUMI-6 LNPs achieved ​20.3% gene editing efficiency in murine lung epithelial cells, surpassing SM-102 (Moderna’s clinical benchmark) and demonstrating ​preferential tropism for lung epithelium over endothelial cells—critical for inhaled therapies targeting cystic fibrosis and surfactant disorders. The brominated tail enhances endosomal escape through optimized protonation dynamics, though explicit pKa values remain unmeasured. Synthesized via high-throughput combinatorial chemistry and refined through AI-driven active learning, LUMI-6 combines scalable production with organ-selective delivery, positioning it as a transformative platform for pulmonary nucleic acid therapeutics.

Acuitas II-10 is an novel ionizable amine lipid used for mRNA delivery from Acuitas Therapeutics patent WO2016176330A1

6Ac1-C12 is an ester-core degradable ionizable cationic lipid designed for mRNA delivery, featuring a unique hexa-acrylate ester core ("6Ac1") conjugated with six N-methyldodecylamine chains ("C12") via solvent-free Michael addition. This branched architecture enables optimal mRNA encapsulation and confers exceptional stability, maintaining consistent ~100 nm particle size for over 30 days at 4°C—crucial for cold-chain storage. With a pKa ≈ 6.0, it facilitates pH-responsive endosomal escape through membrane fusion (80% FRET signal increase at pH 5.5) and efficient cytoplasmic mRNA release.Its composition allows precise organ targeting: in conventional four-component LNPs, 98% hepatic mRNA expression occurs post-IV administration, primarily in endothelial cells (60% transfection efficiency). Cholesterol removal enables lung-specific accumulation and translation via three-component formulations, overcoming historical hepatic off-targeting. The lipid shows negligible cytotoxicity in vitro (>85% cell viability) and no significant organ damage in vivo (ALT/AST/BUN/CREA levels comparable to PBS controls). Its degradable ester core hydrolyzes into smaller metabolites, enhancing biocompatibility. Modular compatibility with DOTAP/DDAB cationic lipids expands applicability for pulmonary or splenic targeting, establishing 6Ac1-C12 as a versatile platform for organ-selective mRNA therapeutics.

Lipid B1​ is a next-generation ionizable lipid engineered for superior mRNA delivery, featuring a patented ​β-isobutylglutarate branching linker​ that optimizes nanoparticle assembly and intracellular release. Its unique structure combines a pH-responsive tertiary amine headgroup with twin C18 alkyl tails connected via biodegradable ester bonds, enabling precise control over lipid packing and endosomal escape. Preclinical studies demonstrate that Lipid B1-based LNPs (bLNPs) achieve ​**>75% transfection efficiency in vitro​ at ultra-low mRNA doses (1 μg), outperforming commercial benchmarks like SM-102. In vivo, subcutaneous administration of bLNPs delivers ​10-fold higher luciferase expression**​ than linear-chain analogs, with targeted biodistribution to lymph nodes and tumor sites. Clinically relevant data show 100% tumor prevention in prophylactic cancer vaccine models and 70% tumor regression in therapeutic settings when combined with checkpoint inhibitors. The ester-based backbone ensures rapid metabolic clearance, minimizing systemic toxicity risks (NOAEL >10 mg/kg in mice). Compatible with mRNA, siRNA, and CRISPR-Cas9 payloads, Lipid B1 is ideal for vaccines, gene therapies, and immuno-oncology. Its scalable 3-step synthesis (yield >80%) and lyophilization stability (-80°C, 12 months) make it a cost-effective solution for GMP-grade production. For advanced delivery with unmatched safety and efficacy, Lipid B1 sets a new standard in nucleic acid therapeutics.

Lipid 119-23 is an ionizable lipid for mRNA delivery. 119-23 LNP exhibits an enhanced capability to express functional mCre in several categories of immune cells, spanning the liver, spleen and lung.

​TOT-5​​, a tri-oleoyl-Tris ionizable lipid (pKa 6.2), enables splenic B cell-targeted mRNA delivery via 15% DSPC-incorporated LNPs. Its charge-neutral, hydrophobic surface minimizes hepatic ApoE uptake and enhances complement C3 adsorption, facilitating CD21/35-mediated uptake by marginal zone B cells. In vivo, intravenous 15%DSPC-LNPs showed 8-fold higher spleen-to-liver luciferase expression vs 3%DSPC, with anti-CD21/35 blocking 60% B cell uptake. Intramuscular administration induced robust OVA-specific IgG (10^5 titer) and CTL responses (3.5% tetramer+ CD8+ T cells) while reducing hepatotoxicity (ALT/AST levels ≤40 U/L vs SM-102-LNPs' 80-120 U/L). Cryo-ET confirmed stable lamellar structures (80-100 nm, ζ-potential -2 mV). This formulation achieves safe, ligand-free splenic targeting for mRNA vaccines.