Conventional drug administration predominantly relies on tablets, capsules, or injections, where active molecules passively follow systemic circulation. A significant portion of these agents undergoes premature metabolism or distribution in non-target tissues, limiting therapeutic efficiency. As a result, oral, transdermal, and inhalable delivery routes have emerged as key alternatives due to their convenience, patient compliance, and potential for self-administration. Nanotechnology has further revolutionized these alternative pathways by reducing drug particle size to the 10-500 nm range and enabling surface functionalization with polysaccharides, lipids, or targeting ligands. This allows drugs to acquire enhanced solubility, stability, and distribution profiles at the molecular level, providing unprecedented temporal and spatial control over delivery.
Intravenous injection requires skilled handling, and repeated venous access increases the risk of infection and local tissue irritation. Subcutaneous or intramuscular administration can also induce discomfort and local reactions. Oral tablets are often limited by enzymatic degradation and first-pass metabolism, resulting in low bioavailability for proteins and peptides. Transdermal patches face physical constraints imposed by the stratum corneum, which restricts penetration of molecules larger than 500 Da or with unsuitable lipophilicity. Inhalable formulations can suffer from inefficient lung deposition if particle size exceeds 5 μm, leading to drug loss in the oropharyngeal region and triggering coughing. Collectively, these limitations highlight the challenges in simultaneously optimizing solubility, stability, targeting, and controlled release with conventional formulations.
Oral delivery leverages the extensive absorptive surface of the gastrointestinal tract, including microvilli and villi structures, enabling high drug uptake. Modern formulations can sustain release for 12-24 hours, enhancing patient adherence.
Transdermal delivery circumvents gastrointestinal degradation and first-pass metabolism, maintaining stable systemic drug levels for extended periods, making it suitable for chronic therapy such as hormonal, analgesic, or smoking cessation agents.
Inhalation delivery targets the alveolar region with a total surface area of approximately 140 m2 and a minimal air-blood barrier (~0.5 μm), enabling near-instantaneous systemic absorption within 1-3 seconds. This route is particularly advantageous for rapid systemic or localized pulmonary delivery.
These pathways support self-administration, reduce healthcare costs, and expand the spatiotemporal flexibility of drug therapy.
Encapsulation within nanocarriers such as liposomes, polymeric micelles, mesoporous silica, or lipid nanoparticles significantly increases surface-to-volume ratios, improving solubility and stability by 10-50-fold. PEG modification can prolong circulation time and minimize clearance by the reticuloendothelial system. Targeting ligands combined with optimal particle sizing allow accumulation in specific tissues while enabling sustained release. Nanocarriers can also co-encapsulate multiple active agents, facilitating synchronized release and providing a versatile platform for combination therapies.
Fig.1 Transdermal nanoparticle delivery using microneedles1,2.
Oral nanomedicine must navigate multiple physiological barriers, including acidic gastric conditions, bile salts, digestive enzymes, mucus, and intestinal epithelium. The integration of "protection–penetration–release" strategies via materials chemistry, surface engineering, and physiological insights is essential for achieving high oral delivery efficiency.
The gastric environment can reach pH levels as low as 1.2, with pepsin rapidly hydrolyzing many proteins within 30 minutes. Bile salts in the proximal small intestine can destabilize lipid-based carriers. The continuously renewed mucus layer (~20-minute turnover) adsorbs cationic nanoparticles, restricting penetration. Additionally, intestinal transporters such as PepT1 favor small peptides but often do not recognize nanoparticulate carriers, resulting in oral bioavailability as low as 0.1% of the administered dose.
Cationic polymers such as chitosan and its derivatives can electrostatically interact with mucus, extending intestinal residence to 4–6 hours. Enteric coatings using polymers like Eudragit S100/L100 remain intact under gastric pH and dissolve selectively in the intestinal lumen. Hybrid lipid–polymer nanoparticles with a phospholipid outer layer and PLGA core can simultaneously encapsulate hydrophilic and hydrophobic drugs; the phospholipid shell resists bile salt washout while the core provides zero-order release kinetics. Preclinical studies demonstrate that oral insulin delivered via chitosan-PLGA nanoparticles maintains glucose-lowering activity for up to 12 hours, achieving relative bioavailability of 11.7%.
Nanoparticles under 100 nm can traverse M cells in Peyer's patches to access lymphoid tissue. Surface conjugation with ligands such as vitamin B12, transferrin, or Fc fragments enables receptor-mediated transport. Incorporation of cell-penetrating peptides like R8 or Penetratin facilitates endocytic uptake across epithelial cells, enhancing transcellular transport by 5–8 fold without compromising barrier integrity.
Intelligent release mechanisms include pH-sensitive linkages that dissolve in the distal intestine (pH 7.4-7.8), enzyme-responsive carriers activated by specific gut enzymes, and thermosensitive or magnetically responsive nanoparticles enabling externally triggered release. Advanced closed-loop systems integrate glucose-responsive hydrogels with insulin, providing accelerated release in response to elevated postprandial glucose and slowed release as levels normalize, maintaining consistent systemic concentrations with minimal dosing frequency.
Through the convergence of advanced materials, surface engineering, and physiological design, oral nanocarriers are redefining the paradigm of oral delivery. They offer high efficiency, enhanced stability, and patient-centric administration for proteins, nucleic acids, and poorly soluble small molecules, challenging traditional assumptions that injectable formulations are inherently superior.
BOC Sciences provides versatile nanoparticles with diverse compositions and functional modifications, customized solutions for your delivery needs.
The skin serves as both a protective interface and a promising portal for drug administration. Its outermost stratum corneum, composed of keratinized cells and lipid bilayers arranged in a "brick-and-mortar" structure, forms a formidable barrier that restricts the penetration of most therapeutic molecules. Conventional transdermal formulations are typically limited to small, lipophilic compounds. The integration of nanotechnology has transformed this paradigm by decoupling the processes of "penetration" and "retention," allowing drugs to traverse skin layers in a controlled manner while maintaining structural stability. This approach enables both local and systemic delivery with sustained release characteristics.
The stratum corneum, typically 10–20 μm thick, restricts the passage of compounds exceeding 500 Da or with logP values outside the 1–3 range. However, specialized skin appendages such as hair follicles and sweat glands, though accounting for only about 0.1% of the total skin area, offer low-resistance pathways for nanoparticle entry. Flexible lipid vesicles under 70 nm can transiently disrupt intercellular lipid packing, allowing deeper penetration into the epidermis up to 100 μm. Slightly cationic nanoparticles can interact electrostatically with the negatively charged skin surface, prolonging residence time to nearly 48 hours and forming localized reservoirs for subsequent sustained release. In vitro diffusion studies have demonstrated that 40 nm cationic liposomes can enhance transdermal flux nearly tenfold compared with free drug formulations, with minimal irritation.
Lipid-based nanocarriers such as solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) exhibit excellent biocompatibility and high affinity with skin lipids, improving drug solubilization and diffusion through the epidermis. SLNs remain solid at the skin surface to prevent premature leakage, while undergoing crystalline transformation under subcutaneous temperature to trigger controlled drug release. Polymer-based nanoparticles, particularly poly(lactic-co-glycolic acid) (PLGA) systems, provide enhanced structural integrity and degradation-controlled release profiles. Their degradation byproducts, lactic and glycolic acids, are naturally metabolized, minimizing accumulation risk. Hybrid "core–shell" nanostructures that combine a lipid shell with a polymeric core integrate rapid initial release with prolonged diffusion-driven delivery, offering dual-phase kinetics ideal for sustained transdermal applications.
One of the key advantages of transdermal nanocarriers is their ability to establish a localized depot within the skin. Once deposited, the nanoparticles slowly release the drug into the epidermal and dermal layers, maintaining steady-state concentrations while reducing dosing frequency. For localized inflammatory or pain-related conditions, nanosystems can accumulate preferentially at affected regions, achieving higher local concentrations while minimizing systemic exposure. Such controlled retention and release behavior contributes to improved therapeutic precision and user compliance.
Microneedle technology creates microscale channels through the stratum corneum, dramatically enhancing skin permeability. Dissolving microneedles, typically composed of biocompatible polymers such as hyaluronic acid or carboxymethyl cellulose, encapsulate nanoparticles within the needle tips. Upon insertion, the tips dissolve in the interstitial fluid, releasing nanoparticles directly into the dermis. Coated microneedles, on the other hand, deposit a thin nanoparticle layer on the needle surface for rapid diffusion upon application. Hybrid platforms that combine microneedle insertion with iontophoresis can further propel charged nanoparticles into deeper dermal layers through mild electrical current, enabling efficient, noninvasive delivery of both small and macromolecular agents.
Pulmonary administration provides rapid absorption and high bioavailability by delivering drugs directly to the lungs, leveraging the extensive alveolar surface area and thin air–blood barrier. Nanoparticle engineering allows precise control of aerodynamic behavior, enhancing lung deposition, retention, and release dynamics. This route offers a versatile and patient-friendly alternative for both local and systemic drug delivery.
The alveolar surface spans approximately 140 m², with a barrier thickness of only 0.2–0.6 μm, enabling exceptionally fast absorption. Pulmonary administration bypasses hepatic first-pass metabolism, allowing efficient entry of certain biomolecules into systemic circulation. However, this route faces major challenges, including complex airway branching, mucociliary clearance, and alveolar macrophage phagocytosis. Effective inhalable nanoparticles must balance aerodynamic diameter, surface charge, and hydrophilicity to achieve deposition, avoid clearance, and release the payload efficiently.
Purely nanoscale particles tend to aggregate or be exhaled due to low inertia. To address this, particle engineering strategies produce microparticles with aerodynamic diameters between 1 and 5 μm that encapsulate or assemble from nanoscale components. These porous, low-density microcarriers efficiently deposit within the lungs and subsequently disintegrate to release embedded nanoparticles. Liposomal or polymeric microspheres exemplify this concept, reconstituting into nanostructures upon exposure to lung humidity, thereby combining deposition efficiency with targeted delivery and extended residence time.
Efficient delivery to the deep lung requires precise control over particle aerodynamics and surface chemistry. Slightly hydrophilic particles with aerodynamic diameters of 1–3 μm can traverse airflow dynamics and reach alveolar regions. Nanoparticles coated with hydrophilic polymers such as polyethylene glycol exhibit "stealth" properties that reduce interactions with surfactant proteins and delay macrophage uptake, allowing extended absorption time. In addition, ligand-conjugated nanoparticles targeting receptors on alveolar epithelial cells or immune cells can enhance selective uptake and improve pulmonary bioavailability.
Aerosol formulations must remain stable during storage, aerosolization, and lung deposition. Coating nanoparticles with cholesterol–phospholipid membranes or incorporating glass-forming excipients can enhance thermal and humidity stability, preventing aggregation or drug leakage. Controlled release in the lung can be achieved using biodegradable polymer matrices that degrade slowly over time, or smart nanocarriers responsive to local cues such as pH, enzymatic activity, or moisture. These strategies extend the duration of drug action and reduce dosing frequency, supporting more consistent and efficient pulmonary delivery.
Nanotechnology has transformed drug delivery from static formulations into programmable systems capable of tunable release, controlled targeting, and multi-pathway integration. By adjusting physicochemical parameters such as particle size, surface chemistry, degradation rate, and environmental responsiveness, delivery systems can be tailored to the molecular properties of each active ingredient and its intended route of administration.
Low aqueous solubility remains a major limitation for many new molecular entities. Nanocrystals, self-emulsifying systems, and amorphous solid dispersions enhance dissolution rate and absorption by increasing surface area and reducing crystallinity.
Mesoporous silica-lipid core-shell nanoparticles, for instance, utilize nanoscale confinement to suppress drug recrystallization while the lipid exterior mitigates precipitation under gastric conditions. Polymeric micelles enable co-loading and sequential release of multiple actives. Surface modification with PEG or vitamin E derivatives improves interaction with chylomicron receptors, facilitating intestinal lymphatic uptake and markedly enhancing systemic exposure, providing a technological foundation for efficient oral delivery of challenging compounds.
Transdermal nanocarriers offer a noninvasive route for sustained and localized delivery. Flexible liposomes, solid lipid nanoparticles, and nanogels can form a drug reservoir within the skin, maintaining stable concentrations for extended durations. For hormone regulation, nanostructured lipid carriers (NLCs) integrated with microneedle arrays allow single-time administration followed by gradual degradation and controlled release. Such platforms reduce dosing frequency and maintain steady systemic levels while improving patient adherence and comfort. In pain management, similar nanosystems can localize active molecules in inflamed tissues, enabling prolonged analgesic effects and minimizing systemic exposure.
Pulmonary delivery combines rapid absorption with avoidance of first-pass metabolism, offering distinct pharmacokinetic advantages. Through particle engineering, nanoparticles can be embedded in porous microspheres with aerodynamic diameters between 1–5 μm, optimizing both deep lung deposition and retention. Lipid–polymer hybrid nanoparticles achieve stable encapsulation and controlled release, while flexible liposomes or amphiphilic prodrug micelles utilize active uptake mechanisms via alveolar cells to enhance systemic bioavailability. These approaches enable needle-free delivery of macromolecules and peptides, demonstrating the broad potential of inhalation-based nanocarrier systems.
The integration of multiple delivery routes represents an emerging paradigm in advanced drug delivery design. By combining fast-acting and long-acting modules within a single platform, formulations can achieve multi-phase release-rapid onset during acute phases, followed by sustained maintenance. For instance, inhalable nanocarriers can provide immediate systemic absorption, while transdermal microneedle patches deliver prolonged release over several days. Hybrid strategies combining oral, inhalation, and transdermal routes can also establish localized reservoirs while maintaining systemic availability. More sophisticated systems incorporate stimuli-responsive mechanisms that adjust release profiles in response to environmental triggers such as pH, enzymatic activity, or hydration levels, creating self-regulated, adaptive drug delivery platforms.
The development of nanoparticle-based drug delivery systems requires a systematic progression from structural design to performance verification and in vivo behavior analysis. Each stage depends on precise, reproducible evaluation techniques that bridge laboratory observations with physiological relevance. Robust analytical systems not only validate formulation performance but also guide optimization, scalability, and functional integration.
In vitro modeling plays a pivotal role in predicting the transport efficiency and stability of nanocarriers.
For oral delivery, dynamic gastrointestinal simulation models replicate pH gradients, enzymatic degradation, and bile salt interactions, enabling accurate evaluation of nanoparticle integrity and drug release under physiologically relevant conditions. Three-dimensional intestinal organoids and Caco-2 monolayers are frequently used to assess epithelial permeability and cellular uptake, while microfluidic "gut-on-a-chip" systems integrate electrical impedance sensing to monitor tight-junction integrity in real time.
In transdermal delivery, reconstructed full-thickness skin models combined with Franz diffusion cells allow the quantification of drug permeation across the stratum corneum, epidermis, and dermis. Confocal Raman spectroscopy provides non-destructive, micrometer-resolution mapping of nanoparticle distribution along skin layers, clarifying penetration pathways through intercellular and follicular routes.
For inhalation studies, air–liquid interface cultures of respiratory epithelial cells and "breathing–stretch" microfluidic chips simulate the cyclic mechanical motion of alveoli. These platforms enable analysis of particle deposition, diffusion, and clearance dynamics under controlled airflow and humidity conditions, thus providing quantitative data for optimizing pulmonary formulations.
Permeation, absorption, and retention studies are essential for understanding how nanoparticles interact with biological barriers. Permeation assays measure the transport rate of drugs across cellular or tissue membranes, while absorption models focus on the uptake and intracellular trafficking of nanoparticles prior to systemic entry. Retention studies quantify how long a formulation remains localized at the target site, influencing both efficacy and release kinetics. Advanced analytical tools such as fluorescence labeling, radiotracing, and high-resolution confocal microscopy allow visualization of nanoparticle trajectories in real time. Ex vivo lung perfusion models combined with gamma imaging enable dynamic monitoring of nanoparticle residence time, providing valuable insights for designing sustained-release or biodegradable systems with predictable clearance behavior.
The physicochemical attributes of nanoparticles determine their colloidal stability, release kinetics, and in vivo fate. Fundamental parameters such as particle size distribution, zeta potential, and morphology are routinely characterized using dynamic light scattering, electrophoretic mobility, and electron microscopy. For inhalable systems, additional aerodynamic parameters must be evaluated, including aerodynamic diameter (Da), fine particle fraction (FPF), and spray velocity. Laser diffraction coupled with high-speed imaging captures droplet formation and dispersion within milliseconds, while computational fluid dynamics (CFD) modeling predicts deposition profiles along the oropharyngeal and bronchial airways. For dry powder or lyophilized formulations, dynamic vapor sorption–Raman spectroscopy provides simultaneous measurement of hygroscopicity and crystallinity transitions. This integrated approach accelerates formulation screening and stability assessments. Atomic force microscopy further reveals surface roughness, porosity, and interparticle cohesion, correlating microstructural characteristics with aerosolization performance.
Bioavailability quantifies the rate and extent to which an active compound reaches systemic circulation—a key indicator of delivery system performance.
For oral nanoparticles, dual-site intestinal perfusion models allow simultaneous sampling of portal and peripheral plasma to distinguish between direct absorption and presystemic loss. Isotopic labeling techniques enhance accuracy by differentiating carrier-released versus re-encapsulated drug fractions.
In transdermal and inhalation studies, microdialysis coupled with mass spectrometry provides high-sensitivity detection (in the nanogram-per-milliliter range), capturing both early burst release and subsequent sustained phases. Concurrent monitoring of lymphatic fluid levels further elucidates the contribution of lymphatic transport, particularly relevant for lipid-based nanocarriers designed for prolonged systemic exposure.
BOC Sciences is committed to advancing the frontiers of drug delivery through cutting-edge nanotechnology. The company has established deep expertise across oral, transdermal, and inhalable nanocarrier systems, providing integrated capabilities in custom nanocarrier design, material selection, formulation optimization, analytical characterization, and collaborative research solutions. By combining advanced materials science with precision engineering, BOC Sciences enables the development of high-performance, reproducible, and precisely controlled nanocarriers that improve drug stability, bioavailability, and targeted delivery efficiency.
BOC Sciences specializes in the design and customization of nanocarriers tailored to overcome the specific physiological challenges of different administration routes.
Oral Delivery Systems: To address the acidic and enzymatic conditions of the gastrointestinal tract, the company develops pH-sensitive nanocarriers that maintain structural integrity in the stomach but dissolve or degrade in the higher pH of the intestine, achieving site-specific release. Additionally, mucoadhesive nanocarriers extend residence time along the intestinal mucosa, promoting absorption efficiency and improving systemic availability. These design strategies allow for controlled, targeted, and efficient oral drug delivery.
Transdermal Delivery Systems: For transdermal applications, the main challenge is overcoming the skin's stratum corneum barrier. BOC Sciences employs lipid-based carriers such as solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC), which exhibit excellent biocompatibility and can effectively integrate with skin lipids. These carriers facilitate drug solubilization and penetration into deeper skin layers, creating a localized drug reservoir and supporting sustained or site-specific delivery, ideal for continuous or controlled therapeutic interventions.
Inhalable Delivery Systems: Pulmonary delivery requires precise control of particle aerodynamic properties. BOC Sciences customizes polymeric and lipid-based nanoparticles engineered to achieve aerodynamic diameters in the optimal 1–5 μm range, maximizing deposition in the deep lung. The company emphasizes formulation stability, dispersibility, and performance under dynamic airflow and humidity conditions, ensuring reproducible and efficient inhalation delivery.
Table 1. Nanoparticle Products for Drug Delivery Applications.
| Product Name | Description | Inquiry |
| pH-Sensitive Oral Nanoparticles | Maintain structural integrity in acidic and enzymatic gastric conditions and release drugs in the higher pH of the intestine, enabling site-specific intestinal delivery and improved drug absorption and bioavailability. | Inquiry |
| Mucoadhesive Oral Nanoparticles | Extend residence time along the intestinal mucosa to enhance drug absorption, enabling controlled release and targeted delivery. | Inquiry |
| Solid Lipid Nanoparticles | Lipid-based carriers that integrate with skin lipids to penetrate the stratum corneum and deliver drugs to deeper skin layers, forming a localized drug reservoir. | Inquiry |
| Nanostructured Lipid Carriers | Improved lipid carriers with high biocompatibility and drug solubilization capacity, enabling transdermal controlled release and targeted delivery. | Inquiry |
| Polymeric Inhalable Nanoparticles | Tunable aerodynamic diameter (1–5 μm) for optimal deep lung deposition, improving distribution uniformity and reproducibility in pulmonary delivery. | Inquiry |
| Lipid-Based Inhalable Nanoparticles | Lipid nanoparticles optimized for pulmonary delivery, ensuring stable dispersion, aerodynamic performance, and efficient inhalation delivery. | Inquiry |
| Fluorescent/Radiolabeled Nanoparticles | Enable in vitro and in vivo tracking of nanoparticle absorption, distribution, and retention for real-time quantitative monitoring and delivery optimization. | Inquiry |
Material selection and formulation refinement are critical determinants of nanocarrier performance, stability, and functionality.
Comprehensive Material Library: BOC Sciences maintains an extensive repository of functional materials, including synthetic phospholipids, PEG derivatives, block copolymers, and cyclodextrin derivatives. These materials form the foundation for engineering multifunctional nanocarriers, including stealth systems, targeted delivery vehicles, and composite structures optimized for specific physicochemical or biological requirements.
AI-Driven Formulation Optimization: The company utilizes an AI-assisted continuous flow platform for accelerated formulation optimization. This system automates synthesis, purification, and particle characterization, producing nanocarriers with precisely controlled size distribution, surface properties, and drug loading within a significantly shortened development timeline. AI algorithms correlate material composition, processing parameters, and particle performance to identify optimal formulations efficiently, supporting rapid development of lipidic, polymeric, or hybrid nanoparticles.
Comprehensive characterization is essential to ensure the reproducibility, stability, and performance of nanoparticle systems.
Physicochemical Characterization: BOC Sciences provides advanced analysis of particle size distribution, zeta potential, morphology, surface chemistry, and encapsulation efficiency. Techniques such as dynamic light scattering, electron microscopy, and electrophoretic mobility are used to assess particle stability, dispersibility, and structural integrity. Additional testing includes release profiling, compositional verification, and stability assessment to guarantee consistent performance across production batches.
In Vitro Evaluation: The company offers a robust platform for in vitro assessment, including cytotoxicity evaluation, cellular uptake studies, and proliferation assays. Fluorescent labeling and quantitative uptake techniques allow detailed observation of nanocarrier internalization and intracellular distribution. These studies provide valuable insights into carrier-cell interactions, guiding optimization of bioavailability, targeting efficiency, and delivery performance.
Table 2. Technical Services for Nanoparticle-Based Delivery Systems.
| Service Name | Description | Inquiry |
| Nanoparticle Characterization & Analysis | Comprehensive analysis of particle size distribution, ζ-potential, morphology, surface chemistry, and encapsulation efficiency to ensure stability and batch-to-batch consistency. | Inquiry |
| Custom Nanocarrier Design | Design of nanoparticles for oral, transdermal, and inhalation delivery to overcome physiological barriers, providing controlled release, targeting, and enhanced absorption. | Inquiry |
| Material Screening & Formulation Optimization | Utilize material libraries and AI-driven continuous flow platforms to optimize particle size, surface properties, and drug loading, accelerating nanoparticle development and production. | Inquiry |
| In Vitro Evaluation Services | Assess cytotoxicity, cellular uptake, and proliferation using 3D organoids and microfluidic chip models to guide nanoparticle delivery efficiency and biocompatibility optimization. | Inquiry |
| Permeation, Absorption & Retention Studies | Quantitatively evaluate nanoparticle absorption, distribution, and retention in target tissues using fluorescent/radiolabeled tracers, microdialysis, and gamma imaging. | Inquiry |
| Aerosol Performance & Fluid Dynamics Testing | Evaluate inhalable nanoparticles' deposition and aerodynamic behavior using laser diffraction, high-speed imaging, and computational fluid dynamics (CFD) modeling to optimize pulmonary delivery. | Inquiry |
BOC Sciences functions as a strategic partner for research and development, providing integrated solutions that span the full spectrum of nanocarrier development.
Comprehensive R&D Support: The company offers contract research capabilities covering target identification, custom synthesis of intermediates and compounds, formulation development, and analytical testing. This integrated approach streamlines workflow and accelerates the development of advanced drug delivery systems.
Innovative Collaboration: BOC Sciences combines expertise in nanotechnology, materials science, and molecular engineering to deliver tailored solutions for complex delivery challenges. Its multidisciplinary approach supports the design, optimization, and validation of nanocarrier systems, enabling clients to advance high-performance formulations efficiently from conceptualization through functional evaluation.
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