PPZ-A10 is an ionizable cationic lipid.It has been used in the generation of lipid nanoparticles (LNPs) for the delivery of siRNA and mRNA in vitro and in vivo. Intraperitoneal administration of LNPs containing PPZ-A10 and encapsulating an mRNA reporter preferentially accumulates in hepatic Kupffer cells and splenic macrophages in mice.

93-O17O is a chalcogen-containing ionizable cationic lipidoid. It has been used in the generation of lipid nanoparticles (LNPs). LNPs containing 93-O17O localize to the spleen after intravenous injection into mice.LNPs containing 93-O17O have been used for the delivery of Cre recombinase and ribonucleoproteins for genome editing in mice and for the intratumoral delivery of cGAMP to enhance cross-presentation of tumor antigens.

U-101 is an ionizable lipid for mRNA delivery. U101-LNP/IL-2F mRNA formulation demonstrats effective antitumor activity and safety.LNPs containing lipid U 101 and encapsulating mRNA encoding a fusion protein composed of IL-2, a linker, and CD25 inhibit tumor growth in an MC-38 mouse xenograft model.

Lipid88​​ is a high-performance, novel ionizable lipid component engineered for advanced mRNA-LNP vaccine delivery. LNP88 formulation demonstrates superior biodistribution, achieving >10-fold higher transfection efficiency in spleen and lymph nodes compared to benchmark lipids like ALC-0315 via intramuscular delivery. When encapsulating antigen-encoding mRNA (e.g., optimized mCSA construct), Lipid-88 based LNPs drive robust humoral and cellular immunity, enabling complete protection against challenging SARS-CoV-2 variants (WA1/2020, Omicron BA.1, BQ.1) in preclinical models. Its design prioritizes potent immunogenicity with favorable safety profiles.

C14-4 (C14-494,Lipid B-4,Lipid B4) is a novel ionizable lipid with the highest T-cell transfection efficiency and low cytotoxicity.The C14-4 ionizable lipid has been explored for CAR-T therapy.To screen the excellent formulations for mRNA delivery, a lipid library of 24 ionizable lipids was constructed to make iLNPs, which were used to deliver luciferase mRNA into Jurkat cells.[115] The optimal iLNPs formulation was C14-4 iLNPs (C14-4 ionizable lipid, DOPE, chol, and PEG at a molar ratio of 35%, 16%, 46.5%, and 2.5%) (Figure 6c). The optimal dose of luciferase mRNA for C14-4 iLNPs was 30 ng. Compared with electroporated CAR T cells, the CAR T cells engineered via C14-4 iLNPs showed potent cancer-killing activity when they were cocultured with Nalm-6 acute lymphoblastic leukemia cells. To obtain a safer and more effective CAR mRNA delivery vehicle, the orthogonal design provided 256 potential formulations, and 16 representative iLNPs formulations were evaluated.Through evaluating the safety, delivery efficiency, and transfection efficiency of 16 iLNPs, the formulation B10 (C14-4 ionizable lipid, DOPE, chol, PEG at a molar ratio of 40%, 30%, 25%, and 2.5%) was screened out as the optimal performing formulation. The luciferase expression based on B10 formulation was increased threefold than the initial formulation. Reducing the accumulation and clearance of iLNPs in the liver can increase the expression of CAR mRNA in T cells, further improving the therapeutic effect of CAR-T. Studies have shown that cholesterol analogs can alter the mechanisms of intracellular circulation and enhance the delivery of mRNA, which may be related to the reduced recognition of iLNPs by the Niemann Pick C1 (NPC1) enzyme.The addition of a hydroxyl group to various locations in the cholesterol molecule can alter the binding kinetics between the modified cholesterol and NPC1, and reduced NPC1 recognition of cholesterol. The results showed that replacement of 25% and 50% 7 α-hydroxycholesterol for cholesterol in iLNPs improved mRNA delivery to primary human T cells in vitro by 1.8-fold and twofold, respectively.C14-4 is one of the ionizable lipids to efficiently deliver mRNA to Jurkat cells or primary human T cells. It will effectively promote the development of mRNA delivery by iLNPs for CAR-T therapy.

PL-40​​ is a ​​cardiolipin-mimetic ionizable lipid​​ engineered for high-efficiency, antibody-free mRNA delivery to T cells. PL 40 LNPs exhibit a mean particle size of ​​120 nm​​, zeta potential of ​​-5.19 mV​​, and >80% mRNA encapsulation efficiency, with excellent plasma stability (≤5% size change after 6h in serum). Cryo-TEM reveals ​​polyhedral nanoparticles​​ with phase-separated domains, while SAXS confirms tight mRNA packing (d-spacing: ​​~3 nm​​ vs. 6.64 nm in conventional LNPs). AFM demonstrates exceptional rigidity (high bending modulus), enabling T cell-selective uptake via actin-mediated endocytosis (>2× higher than ALC0315 LNPs).In primary human T cells, PL40 LNPs achieve ​​>90% transfection​​ at 0.5 μg mRNA dose and sustain >100× higher luciferase expression than benchmark lipids. When delivering circular RNA, they extend protein expression ​​>5 days​​ with superior spleen tropism (spleen:liver ratio = ​​2.63​​). Crucially, they reprogram T cells into functional CAR-Ts in vivo without antibody conjugation, evading exhaustion markers (no Tim-3/PD-1 upregulation). Therapeutically, PL40-based uPAR-targeted CAR mRNA reduces liver fibrosis (​​collagen↓50%​​, ALT↓50%) and rheumatoid arthritis severity (​​clinical scores↓60%​​) by clearing senescent cells. Humanized anti-uPAR CARs delivered via PL40 show near-complete cytotoxicity (>95%) against uPAR+ cells, underscoring clinical translatability.

503O8,12​​ is an ionizable lipidoid synthesized via Michael addition, combining a hydrophilic amine headgroup ("503" series) with two hydrophobic branched acrylate tails (C8 and C12 chains, likely with unsaturated bonds). Its design emphasizes organ-specific delivery, exhibiting ​​spleen-tropic targeting​​ in vivo.

YSK 12C4 is an ionizable cationic lipid primarily used to enhance siRNA cellular delivery via multifunctional envelope-type nanodevices (MEND). YSK 12C4 promotes siRNA uptake and endosomal escape, effectively silencing genes in human immune cell lines.

Lipid C12-A1 is an ionizable lipid. C12-A1-LPN is a potent and safe LNP platform to deliver Foxp3 mRNA to CD4+ T cells to engineer immunosuppressive FP3T cells. C12-A1 has a slightly lower average cell viability than C14-A1.

Lipid C14-A1 is an ionizable lipid. C14-A1-LPN is a potent and safe LNP platform to deliver Foxp3 mRNA to CD4+ T cells to engineer immunosuppressive FP3T cells.

9322-O16B is a lipidoid for the efficient delivery of antiCD19 mRNA CAR to murine primary macrophages. LNP 9322-O16B is more efficient than delivery with lipofectamine 2000 (LPF2K) or MC3.

113-O12B is a disulfide bond-containing ionizable cationic lipidoid. 113-O12B LNP, an LN-targeting LNP delivery system, is developed for a mRNA cancer vaccine. The 113-O12B/mRNA shows enhanced expression in APCs compared with ALC-0315/mRNA, indicating the LN-specific targeting ability.

OF-C4-Deg-Lin is a novel ionizable lipid for RNA delivery. OF-C4-Deg-Lin LNPs entrapping mRNA coding for luciferase induce the majority of protein expression in the spleen, with minimal translation in the liver, and negligible translation in other organs. OF-C4-Deg-Lin LNPs entrapping mRNA coding for luciferase induce the majority of protein expression in the spleen, with minimal translation in the liver, and negligible translation in other organs. To improve the mRNA delivery to extrahepatic tissues, a series of degradable diketopiperazine-based ionizable lipids were synthesized. Through evaluating the mRNA functional activity delivered by iLNPs, it was found that the ionizable lipids with doubly unsaturated lipid tails and linkers containing a length of four carbon aliphatic chain (Of-C4-Deg-Lin) could deliver the mRNA more efficiently. Moreover, compared with cKK-E12 and Invivofectamine, Of-C4-Deg-Lin could specifically induce more than 85% of firefly luciferase expression in spleen,minimal expression in the liver, and insignificant expression in other tissues.

Lipid 8 iLNPs were used to deliver CRISPR-Cas9 mRNA and sgRNA which targeted to the PLK1 gene. The safety and excellent intracerebral diffusion performance of lipid 8 iLNPs ensured that the survival of murine glioblastoma multiforme (GBM) mice was extended. The median survival was extended by approximately 50% and the overall survival was increased by 30%. The treatment of metastatic adenocarcinoma was executed by the EGFRtargeted lipid 8 iLNPs. These iLNPs possessed the ability of tumor targeting, which could increase the accumulation of CRISPR-Cas9 mRNA and sgRNA within the tumor cells. After a single intraperitoneal administration,
80% PLK1 gene was edited and the overall survival of mice with high-grade ovarian cancer malignant ascites was enhanced by
80% . These results demonstrate the clinical potential of CRISPR-Cas9 gene editing system can be delivered by iLNPs for treating tumors, and provide new ideas for tumor gene therapy.

MK-16 is a specialized lipid designed to traverse the blood-brain barrier (BBB) for effective mRNA delivery. Its formulation, MK 16 BLNP, leverages dual mechanisms involving caveolae and γ-secretase to facilitate BBB penetration, ensuring the targeted and efficient transport of functional mRNA to diverse brain cell types. Demonstrating excellent tolerability across a range of dosing regimens, MK16 BLNP represents a promising platform for brain-targeted therapeutic applications.

TD5 is a brain-targeting lipid nanoparticle (BLNP) engineered for efficient mRNA delivery to the central nervous system (CNS) via intrathecal injection. It incorporates a tryptamine-derived ionizable lipid headgroup, myristic acid hydrocarbon tails, and a biodegradable carbonate ester linker, enabling pH-dependent mRNA encapsulation (81.7% efficiency) and brain cell-specific targeting. With a hydrodynamic diameter of 107.5 nm, near-neutral pKa (7.30), and mild positive charge, TD 5 demonstrates superior CNS tropism through serotonin receptor (5-HT1A)-mediated endocytosis. In vitro, TD-5 achieved 80.8% GFP expression in SH-SY5Y neuronal cells, outperforming MC3 LNPs by 50-fold. Following intrathecal administration in mice, TD-5 mediated GFP expression in 29.6% of neurons and 38.1% of astrocytes brain-wide, with 10-fold higher CNS specificity than peripheral organs. Genome editing studies showed TD5-delivered Cas9/sgRNA induced tdTomato activation in ≈30% of neurons and 40% of astrocytes across key brain regions. Safety profiling revealed minimal systemic immune responses (lower IL-6, IL-12p40 vs MC3 LNPs), normal hepatic/renal biomarkers, and no histopathological toxicity. The optimized structure balances myristic chain hydrophobicity for membrane interaction, ionizable amines for mRNA complexation, and tryptamine-mediated targeting for enhanced CNS uptake, establishing TD5 as a promising platform for CNS gene therapies.

NT1-O14B is a tryptamine-containing cationic lipidoid.1 It has been used in combination with other lipids in the formation of lipid nanoparticles (LNPs). Intravenous administration of LNPs containing NT1-O14B and encapsulating antisense nucleotides against tau decreases tau brain levels in mice.

NT1-O12B, an endogenous chemical and a neurotransmitter-derived lipidoid (NT-lipidoid), is an effective carrier for enhanced brain delivery of several blood-brain barrier (BBB)-impermeable cargos. Doping NT1-O12B into BBB-impermeable lipid nanoparticles (LNPs) gives the LNPs the ability to cross the BBB. NT-lipidoids formulation not only facilitate cargo crossing of the BBB, but also delivery of the cargo into neuronal cells for functional gene silencing or gene recombination.