Solid lipid nanoparticles of irbesartan: preparation, characterization, optimization and pharmacokinetic studies

Brain-targeted delivery of Valsartan using solid lipid nanoparticles labeled with Rhodamine B; a promising technique for mitigating the negative effects of stroke

The brain is a vital organ that is protected from the general circulation and is distinguished by the presence of a relatively impermeable blood brain barrier (BBB). Blood brain barrier prevents the entry of foreign molecules. The current research aims to transport valsartan (Val) across BBB utilizing solid lipid nanoparticles (SLNs) approach to mitigate the adverse effects of stroke. Using a 3²-factorial design, we could investigate and optimize the effect of several variables in order to improve brain permeability of valsartan in a target-specific and sustained-release manner, which led to alleviation of ischemia-induced brain damage. The impact of each of the following independent variables was investigated: lipid concentration (% w/v), surfactant concentration (% w/v), and homogenization speed (RPM) on particle size, zeta potential (ZP), entrapment efficiency (EE) %, and cumulative drug release percentage (CDR) %. TEM images revealed a spherical form of the optimized nanoparticles, with particle size (215.76 ± 7.63 nm), PDI (0.311 ± 0.02), ZP (-15.26 ± 0.58 mV), EE (59.45 ± 0.88%), and CDR (87.59 ± 1.67%) for 72 hours. SLNs formulations showed sustained drug release, which could effectively reduce the dose frequency and improve patient compliance. DSC and X-ray emphasize that Val was encapsulated in the amorphous form. The in-vivo results revealed that the optimized formula successfully delivered Val to the brain through intranasal rout as compared to a pure Val solution and evidenced by the photon imaging and florescence intensity quantification. In a conclusion, the optimized SLN formula (F9) could be a promising therapy for delivering Val to brain, alleviating the negative consequences associated with stroke.

Nanotechnology-Based Strategies for Extended-Release Delivery of Angiotensin Receptor Blockers (ARBs): A Comprehensive Review

There has been a significant shift in the perception of hypertension as an important contributor to the global disease burden. Approximately 6 % and 8 % of pregnancies are affected by hypertension, which can adversely affect the mother and the fetus. Furthermore, a hypertensive individual is at increased risk of developing kidney disease, arterial hardening, eye damage, and strokes. Using angiotensin receptor blockers (ARBs) is widespread in treating hypertension, heart failure, coronary artery disease, and diabetic nephropathy. Despite this, some ARBs have limited use due to their poor oral bioavailability and water solubility. To tackle this, a variety of nanoparticle (NP)-based systems, such as polymeric NPs (i. e., dendrimers), polymeric micelles, polymer-drug conjugates, lipid NPs, nanoemulsions, self-emulsifying drug delivery systems (SEDDS), solid lipid NPs (SLNs), nanostructured lipid carriers (NLCs), carbon-based nanocarriers, inorganic NPs, and nanocrystals, have been recently developed for efficient delivery of losartan, Valsartan (Val), Olmesartan (OLM), Telmisartan (TEL), Candesartan, Eprosartan, Irbesartan, and Azilsartan to target cells. This review article provides a literature-based comparison of the various classes of ARBs, their mechanisms of action, and an overview of the nanoformulations developed for ARB delivery and successfully applied to managing hypertension, diabetic complications, and other conditions.

Construct Fluorescent Solid Lipid Nanoparticles from Bacterial Outer Membrane Vesicles to Study their Properties and Potential Applications as In Vivo and Invitro Imaging Agents

In this study, the new solid lipid nanoparticles were created by combining fluorescent dye, fatty acid, lipid, and bacterial outer membranes. The synthesised particles were roughly 95-100 nm in size. Vero cells cultivated with these nanoparticles showed no cytotoxicity in 5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT) assay. In the cell uptake studies, the vero cell line was employed. Cell lines absorbed fluorescent solid lipid nanoparticles (FSL NPs) better, according to the findings. The confocal microscopy results revealed a significant accumulation of FSL NPs in the cytoplasm over time. The results of small animal imaging employing BALB/c mice revealed that the nanoparticles generated provided high contrast signals. Overall, the OMVs-based FSL NPs system offers a unique imaging tool for studying intracellular interactions as well as a viable tool for drug delivery.

Development and evaluation of sunscreen cream containing solid lipid nanoparticles of Spinacia oleraceae

More research is needed to understand the benefits of environmentally safe and human-friendly herbal-based sunscreen agents against ultraviolet (UV) radiation. Because of the toxicity of synthetic chemicals in photoprotective agents, researchers were increasingly focusing on herbal photoprotective formulations. The photoprotective agent's skin retention can be considerably improved by forming solid lipid nanoparticles (SLN). The study's objective is to evaluate the photoprotective potential of sunscreen cream containing spinach (Spinacia oleracea)-loaded SLN. A solvent emulsification technique was used to develop the spinach-loaded SLN. The various characterization techniques of the developed SLN were performed. Out of all the formulations, the optimized one was fitted into cream and estimated for its photoprotective action. The images obtained from scanning electron microscopy (SEM) revealed the morphological characteristics of the prepared SLN. The sunscreen cream's viscosity, spreadability, extrudability, and release rate were within acceptable limits. The formulation's in vitro and in vivo sun protection factor (SPF) was reported to be 15.9 and 14.75, respectively. The results indicated that the prepared formulation possesses good photoprotective action. The accelerated stability tests were carried out with no noticeable changes in the parameters. Our work demonstrated the possibility of using spinach-loaded SLN as a photoprotective agent in cosmetic formulations.

Preparation and characterization of amoxapine- and naringin-loaded solid lipid nanoparticles: drug-release and molecular-docking studies

Aim: Amoxapine (AMX) has been reported to be metabolized by CYP3A4 and CYP2D6. Naringin (NG) has been reported to inhibit CYP enzymes. Therefore, the current work was designed to develop AMX solid lipid nanoparticles (AMX-SLNs) and NG-SLNs for better therapeutic performance. Materials & methods: AMX-SLNs and NG-SLNs were prepared and characterized. AMX and NG interactions with CYP450s were studied with molecular docking to rationalize the effectiveness of the combination. Results: AMX-SLNs and NG-SLNs showed nanometric size with a sustained in vitro drug-release profile. NG showed a higher predicted binding affinity for CYP3A4 and CYP2D6, suggesting the potential for inhibition. Conclusion: The developed formulations were thoroughly characterized along with molecular docking data indicating promising AMX and NG combinations that may show good therapeutic activity.

How to Improve Solubility and Dissolution of Irbesartan by Fabricating Ternary Solid Dispersions: Optimization and In-Vitro Characterization

The purpose of this study is to improve the solubility and dissolution of a poorly soluble drug, Irbesartan, using solid dispersion techniques. For that purpose, different polymers such as Soluplus^®, Kollidon^® VA 64, Kolliphor^® P 407, and Polyinylpyrrolidone (PVP-K30) were used as carriers at different concentrations to prepare solid dispersion formulations through the solvent evaporation method. In order to prepare binary dispersion formulations, Soluplus^® and Kollidon^® VA 64 were used at drug: polymer ratios of 1:1, 1:2, 1:3, and 1:4 (w/w). Saturation solubility of the drug in the presence of used carriers was performed to investigate the quantitative increase in solubility. Dissolution studies were performed to explore the drug release behavior from the prepared dispersions. Additionally, the characterization of the prepared formulations was carried out by performing DSC, SEM, XRD, and FTIR studies. The results revealed that among binary systems, K₄ formulation (Drug: Kollidon^® VA 64 at ratio of 1:4 w/w) exhibited optimal performance in terms of increased solubility, drug release, and other investigated parameters. Furthermore, ternary dispersion formulations of the optimized binary formulation were prepared with two more polymers, Kolliphor^® P 407 and Polyvinylpyrrolidone (PVP-K30), at (Drug: Kollidon^® VA 64:ternary polymer) ratios of 1:4:1, 1:4:2, and 1:4:3 (w/w). The results showed that KPVP (TD₃) exhibited the highest increase in solubility, as well as dissolution rate, among ternary solid dispersion formulations. Results of solubility enhancement by ternary solid dispersion formulations were also supported by FTIR, DSC, XRD, and SEM analysis. Conclusively, it was found that the ternary solid dispersion-based systems were more effective compared to the binary combinations in improving solubility as well as dissolution of a poorly soluble drug (Irbesartan).

Role of solid lipid nanoparticle for the delivery of Lipophilic Drugs and Herbal Medicines in the treatment of pulmonary hypertension

Pulmonary arterial hypertension (PAH) is an uncommon condition marked by elevated pulmonary artery pressure that leads to right ventricular failure. The majority of drugs are now been approved by FDA for PAH, however, several biopharmaceutical hindrances lead to failure of the therapy. Various novel drug delivery systems are available in the literature from which lipid-based nanoparticles i.e. solid lipid nanoparticle is widely investigated for improving the solubility and bioavailability of drugs. In this paper, the prototype phytoconstituents used in pulmonary arterial hypertension have limited solubility and bioavailability. We highlighted the novel concepts of SLN for lipophilic phytoconstituents with their potential applications. This paper also reviews the present state of the art regarding production techniques for SLN like High-Pressure Homogenization, Micro-emulsion Technique, and Phase Inversion Temperature Method, etc. Furthermore, toxicity aspects and in vivo fate of SLN are also highlighted in this review. In a nutshell, safer delivery of phytoconstituents by SLN added a novel feather to the cap of successful drug delivery technologies.

Skin Penetration Enhancer-Incorporated Lipid Nanovesicles (SPE-LNV) for Skin Brightening and Wrinkle Treatment

In this work, we utilize skin penetration enhancers (SPEs) such as ceramide and fatty acids in lipid nanovesicles to promote the transdermal delivery of active ingredients. These SPE-incorporated lipid nanovesicles (SPE-LNV) interact with the constituents of skin's outermost stratum corneum (SC) layer, enabling even niacinamide and adenosine with high water solubility to effectively permeate through, leading to enhanced skin efficacy. We demonstrate by both in vitro and in vivo skin permeation studies that the SPE-LNV formulation containing both ceramide and fatty acids (LNV-CF) exhibits deeper penetration depth and faster permeation rate compared to conventional lipid nanovesicles (LNV) without SPE as well as LNV-C with only ceramide. Moreover, in vivo clinical trials were also performed to confirm that LNV-CF most effectively mediates the delivery of niacinamide and adenosine, resulting in a substantial decrease in melanin index as well as skin wrinkle compared to the control groups. We envision that the strategy of incorporating both ceramide and fatty acids in lipid nanovesicles offers a simple and convenient route for the rapid and effective delivery of water-soluble active ingredients across the skin barrier layer.

Advances in Nanomaterial-Based Platforms to Combat COVID-19: Diagnostics, Preventions, Therapeutics, and Vaccine Developments

The COVID-19 pandemic caused by the SARS-CoV-2, a ribonucleic acid (RNA) virus that emerged less than two years ago but has caused nearly 6.1 million deaths to date. Recently developed variants of the SARS-CoV-2 virus have been shown to be more potent and expanded at a faster rate. Until now, there is no specific and effective treatment for SARS-CoV-2 in terms of reliable and sustainable recovery. Precaution, prevention, and vaccinations are the only ways to keep the pandemic situation under control. Medical and scientific professionals are now focusing on the repurposing of previous technology and trying to develop more fruitful methodologies to detect the presence of viruses, treat the patients, precautionary items, and vaccine developments. Nanomedicine or nanobased platforms can play a crucial role in these fronts. Researchers are working on many effective approaches by nanosized particles to combat SARS-CoV-2. The role of a nanobased platform to combat SARS-CoV-2 is extremely diverse (i.e., mark to personal protective suit, rapid diagnostic tool to targeted treatment, and vaccine developments). Although there are many theoretical possibilities of a nanobased platform to combat SARS-CoV-2, until now there is an inadequate number of research targeting SARS-CoV-2 to explore such scenarios. This unique mini-review aims to compile and elaborate on the recent advances of nanobased approaches from prevention, diagnostics, treatment to vaccine developments against SARS-CoV-2, and associated challenges.

Optimized Nanoparticles for Enhanced Oral Bioavailability of a Poorly Soluble Drug: Solid lipid nanoparticles versus Nanostructured lipid carriers

Rosuvastatin calcium (ROSCa) is an anti-hyperlipidemic drug with only 20% oral bioavailability due to its low solubility and high first-pass metabolism. Therefore, the main purpose of this work was to compare solid lipid nanoparticles to nanostructured lipid carriers and evaluate their effect on solubility improvement and hence the bioavailability of a model insoluble drug.

METHODOLOGY

Different nanosuspensions were formulated using high-speed homogenization and ultrasonication techniques, using Apifil as solid lipid and maisine as liquid lipid. The effect of different variables on quality attributes (particle size, entrapment efficiency (EE), and in vitro release) was studied using the Box-Behnken design. Then, the optimized nanoparticles were lyophilized, filled into capsules, and evaluated. Finally, the optimized formula was clinically evaluated in six healthy human volunteers.

RESULTS

It was observed that the variables had a great impact on EE and particle size. Nanoparticles showed maximum particles of 180.3 nm, and % EE ranged from 40.77% to 91.67%. Capsules loaded with NLCs were found to be more stable than those loaded with SLNs. The clinical study of NLCs-ROSCa showed an enhancement in the C max (8.92 ng/ml) compared to the commercial product (2.56 ng/ml) with approximately 349% relative bioavailability.

CONCLUSION

ROSCa was successfully encapsulated in SLNs and NLCs. The optimized NLCs formulation showed improved quality attributes compared to SLNs. Thus, NLCs loaded formulations could be an effective oral drug delivery system to enhance the bioavailability of insoluble drugs.

Cyclodextrin Complexed Lipid Nanoparticles of Irbesartan for Oral Applications: Design, Development, and In Vitro Characterization

Irbesartan (IR) is an angiotensin II receptor antagonist drug with antihypertensive activity. IR bioavailability is limited due to poor solubility and first-pass metabolism. The current investigation aimed to design, develop, and characterize the cyclodextrin(s) (CD) complexed IR (IR-CD) loaded solid lipid nanoparticles (IR-CD-SLNs) for enhanced solubility, sustained release behavior, and subsequently improved bioavailability through oral administration. Based on phase solubility studies, solid complexes were prepared by the coacervation followed by lyophilization method and characterized for drug content, inclusion efficiency, solubility, and in vitro dissolution. IR-CD inclusion complexes demonstrated enhancement of solubility and dissolution rate of IR. However, the dissolution efficiency was significantly increased with hydroxypropyl-βCD (HP-βCD) inclusion complex than beta-CD (βCD). SLNs were obtained by hot homogenization coupled with the ultrasonication method with IR/HP-βCD inclusion complex loaded into Dynasan 112 and glycerol monostearate (GMS). SLNs were evaluated for physicochemical characteristics, in vitro release, differential scanning calorimetry (DSC), powder X-ray diffractometry (PXRD), and physical stability at room temperature for two months. The optimized SLNs formulation showed particle size, polydispersity index, zeta potential, assay, and entrapment efficiency of 257.6 ± 5.1 nm, 0.21 ± 0.03, -30.5 ± 4.1 mV, 99.8 ± 2.5, and 93.7 ± 2.5%, respectively. IR-CD-SLN and IR-SLN dispersions showed sustained release of IR compared to the IR-CD inclusion complexes. DSC results complimented PXRD results by the absence of IR endothermic peak. Optimized IR-CD complex, IR-SLN, and IR-CD-SLN formulations were stable for two months at room temperature. Thus, the current IR oral formulation may exhibit improved oral bioavailability and prolonged antihypertensive activity, which may improve therapeutic outcomes in the treatment of hypertension and heart failure.

Effect of Different Nail Penetration Enhancers in Solid Lipid Nanoparticles Containing Terbinafine Hydrochloride for Treatment of Onychomycosis

Onychomycosis is considered a stubborn nail fungal infection that does not respond to conventional topical antifungal treatments. This study aimed to develop and characterize novel solid lipid nanoparticles (SLNs) formulae containing terbinafine HCl (TFH) and loaded with different nail penetration enhancers (nPEs). Three (nPEs) N-acetyl-L-cysteine, thioglycolic acid, and thiourea were used. Characterization of the prepared formulae was done regarding particle size, zeta potential, polydispersity index (PDI), entrapment efficiency (EE%), physical stability, in vitro release study, infrared (FT-IR), and their morphological structures. The selected formulae and the marketed cream Lamifen® were compared in terms of their antifungal activity against Trichophyton rubrum as well as their nail hydration and their drug uptake by the nail clippers. Thiourea was the nPE of choice; formulae (N2 and N8), with thiourea, were considered the optimum TFH SLNs containing nPEs. They were selected for their optimum particle size of 426.3 ± 10.18 and 450.8 ± 11.45 nm as well as their highest EE% of 89.76 ± 1.25 and 90.35 ± 1.33, respectively. The in vitro microbiological screening of the antifungal activity of these two formulae showed significantly larger zones of inhibition in comparison with the marketed product. The ex vivo screening of the drug uptake of the two selected formulae was significantly higher than that of the marketed product. The nPE formulae present a very promising option as they showed optimum physicochemical characterization with high antifungal activity and high drug uptake as well as good nail hydration effect.

Differential Scanning Calorimetry (DSC) on Sartan/Cyclodextrin Delivery Formulations

Differential scanning calorimetry (DSC) is a widely utilized method for the interactions of drug molecules with drug delivery systems (DDSs). Herein is described a protocol for studying the interactions and entrapment efficiency of the prototype sartan losartan and the polydynamic, structurally similar irbesartan inside the nontoxic 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD). The thermal scan properties of both sartan molecules have been studied when physically mixed or complexed with the cyclodextrin. The thermograms indeed showed significant differences between the mixtures and complexes, establishing DSC as a valuable method to characterize the state of the drugs in these pharmaceutical formulations.

On the Rational Drug Design for Hypertension through NMR Spectroscopy

Antagonists of the AT1receptor (AT1R) are beneficial molecules that can prevent the peptide hormone angiotensin II from binding and activating the specific receptor causing hypertension in pathological states. This review article summarizes the multifaced applications of solid and liquid state high resolution nuclear magnetic resonance (NMR) spectroscopy in antihypertensive commercial drugs that act as AT1R antagonists. The 3D architecture of these compounds is explored through 2D NOESY spectroscopy and their interactions with micelles and lipid bilayers are described using solid state 13CP/MAS, 31P and 2H static solid state NMR spectroscopy. Due to their hydrophobic character, AT1R antagonists do not exert their optimum profile on the AT1R. Therefore, various vehicles are explored so as to effectively deliver these molecules to the site of action and to enhance their pharmaceutical efficacy. Cyclodextrins and polymers comprise successful examples of effective drug delivery vehicles, widely used for the delivery of hydrophobic drugs to the active site of the receptor. High resolution NMR spectroscopy provides valuable information on the physical-chemical forces that govern these drug:vehicle interactions, knowledge required to get a deeper understanding on the stability of the formed complexes and therefore the appropriateness and usefulness of the drug delivery system. In addition, it provides valuable information on the rational design towards the synthesis of more stable and efficient drug formulations.

Antihypertensive activity and molecular interactions of irbesartan in complex with 2-hydroxypropyl-β-cyclodextrin

Irbesartan (IRB) exerts beneficial effects either alone or in combination with other drugs on numerous diseases, such as cancer, diabetes, and hypertension. However, due to its high lipophilicity, IRB does not possess the optimum pharmacological efficiency. To circumvent this problem, a drug delivery system with 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD) was explored. The 1:1 complex between IRB and 2-HP-β-CD was identified through ESI QTF HRMS. Dissolution studies showed a higher dissolution rate of the lyophilized IRB-2-HP-β-CD complex than the tablet containing IRB at pH = 1.2. DSC results revealed the differences of the thermal properties between the complex and various mixtures consisting of the two components, namely IRB and 2-HP-β-CD. Interestingly, depending on the way the mixture preparation was conducted, different association between the two components was observed. Molecular dynamics (MD) simulations predicted the favorable formation of the above complex and identified the dominant interactions between IRB and 2-HP-β-CD. In vitro pharmacological results verified that the inclusion complex not only preserves the binding affinity of IRB for AT1R receptor, but also it slightly increases it. As the complex formulation lacks the problems of the tablet, our approach is a promising new way to improve the efficiency of IRB.

Lipospheres for Simultaneous Controlled Release and Improved Pharmacokinetic Profiles of Saxagliptin-Enalapril: Formulation, Optimization, and Comparative In Vitro-In Vivo Evaluation

The current study aims at formulating and optimizing lipospheres (LS) by the Box-Behnken design (BBD) from safe biodegradable carnauba wax (CW) to co-administer saxagliptin (SG) and enalapril (EP) for co-existing chronic hypertensive diabetes in order to overcome inadequacies of conventional modes of drug administration. Optimized liposphere formulation (OLF) was selected by a numerical optimization procedure and a comparative in vivo pharmacokinetic study of OLF and commercial brands was also performed. Discrete, free-flowing, spherical, smooth-surface LS having a size range of 5-10 μm and zeta potential of - 20 to - 30 mV were successfully formulated. Compatibility studies by FTIR and DSC proved the lack of interaction of components while XRD suggested the transformation of crystalline drugs to amorphous form. Outcomes of dependent optimizing variables like percentage yield (30-90%), EP-release (32-92%), and SG-release (28-95%) followed a polynomial quadratic model. Pharmacokinetics studies indicated a significantly lower C_max of EP (125.22 ± 6.32) and SG (75.63 ± 3.85) and higher mean T_max values (9.4 h for EP and 10.73 h for SG) from OLF in comparison with reference brands of EP (257.54 ± 8.23 ng/mL) and SG (393.66 ± 2.97 ng/mL). Additionally, a potential rise in half-life and MRT of SG and EP was achieved reaching approximately 2- to 3-fold higher than noted for reference brands. Importantly, the enhanced T_max and AUC_0-24 specified the achievement of enhanced bioavailability of both drugs from LS. Consequently, such an innovative approach could not only control drug release in both in vitro and in vivo analyses but also maintain plasma drug concentration for a longer time without maximizing C_max leading towards effective management of chronic illnesses.

Combination with l-Menthol Enhances Transdermal Penetration of Indomethacin Solid Nanoparticles

This study designed the transdermal formulations containing indomethacin (IMC)—1% IMC was crushed with 0.5% methylcellulose and 5% 2-hydroxypropyl-β-cyclodextrin by the bead mill method, and the milled IMC was gelled with or without 2% l-menthol (a permeation enhancer) by Carbopol^® 934 (without menthol, N-IMC gel; with menthol, N-IMC/MT gel). In addition, the drug release, skin penetration and percutaneous absorption of the N-IMC/MT gel were investigated. The particle sizes of N-IMC gel were approximately 50–200 nm, and the combination with l-menthol did not affect the particle characterization of the transdermal formulations. In an in vitro experiment using a Franz diffusion cell, the skin penetration in N-IMC/MT gel was enhanced than the N-IMC gel, and the percutaneous absorption (AUC) from the N-IMC/MT gel was 2-fold higher than the N-IMC gel. On the other hand, the skin penetration from the N-IMC/MT gel was remarkably attenuated at a 4 °C condition, a temperature that inhibits all energy-dependent endocytosis. In conclusion, this study designed transdermal formulations containing IMC solid nanoparticles and l-menthol, and found that the combination with l-menthol enhanced the skin penetration of the IMC solid nanoparticles. In addition, the energy-dependency of the skin penetration of IMC solid nanoparticles was demonstrated. These findings suggest the utility of a transdermal drug delivery system to provide the easy application of solid nanoparticles (SNPs).

Nanostructured lipid carriers: A potential use for skin drug delivery systems

Skin application of pharmaceutical products is one of the methods used for drug administration. The problem of limited drug penetration via topical application makes searching for safe drug carriers that will provide an expected therapeutic effect of utmost importance. Research into safe drug carriers began with liposome structures, paving the way for work with nanocarriers, which currently play a large role as drug vehicles. Nanostructured lipid carriers (NLC) consist of blended solid and liquid lipids (oils) dispersed in an aqueous solution containing a surfactant. These carriers have many advantages: good biocompatibility, low cytotoxicity, high drug content; they enhance a drug's stability and have many possibilities of application (oral, intravenous, pulmonary, ocular, dermal). The following article presents properties, methods of preparation and tests to assess the quality and toxicity of NLC. This analysis indicates the possibility of using NLC for dermal and transdermal drug application.

Soft- and hard-lipid nanoparticles: a novel approach to lymphatic drug delivery

With the current advance in nanotechnology, the development has accelerated of a number of nanoparticle-type drugs such as nano-emulsions, lipid emulsions, liposomes, and cell therapeutics. With these developments, attempts are being made to apply these new drugs to healing many intractable diseases related to antibody production, autoimmune disorders, cancer, and organ transplantation in both clinical and nonclinical trials. Drug delivery to the lymphatic system is indispensable for treating these diseases, but the core technologies related to the in vivo distribution characteristics and lymphatic delivery evaluation of these particle-type drugs have not yet been established. Additionally, the core technologies for setting up the pharmacotherapeutic aspects such as their usage and dosages in the development of new drugs do not meet the needs of the market. Therefore, it is necessary to consider dividing these particle-type drugs into soft-lipid nanoparticles that can change size in the process of body distribution and hard-lipid nanoparticles whose surfaces are hardened and whose sizes do not easily change in vivo; these soft- and hard-lipid nanoparticles likely possess different biodistribution characteristics including delivery to the lymphatic system. In this review, we summarize the different types, advantages, limitations, possible remedies, and body distribution characteristics of soft- and hard-lipid nanoparticles based on their administration routes. We also emphasize that it will be necessary to fully understand the differences in distribution between these soft- and hard-lipid nanoparticle-type drugs and to establish pharmacokinetic models for their more ideal lymphatic delivery.