| Size | Price | Stock | Qty |
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| 5mg |
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| 10mg |
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| Other Sizes |
| Targets |
PLGA-PEG-MAL does not target a specific biological receptor; it is a biomaterial excipient. The PLGA block undergoes hydrolytic degradation into lactic and glycolic acids, while the PEG block provides biocompatibility and prolongs systemic circulation. The maleimide (MAL) functional group reacts specifically with thiol groups (-SH) via a Michael addition reaction at pH 6.5-7.5, forming a stable thioether bond. This allows the covalent attachment of targeting ligands (e.g., thiolated antibodies, peptides, or aptamers) to the nanoparticle surface, enabling active targeting to specific cell surface receptors. The 50:50 LA:GA ratio influences the degradation rate of the matrix.
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| ln Vitro |
In vitro, PLGA-PEG-MAL itself is not biologically active. However, when conjugated to a targeting ligand (e.g., a thiolated antibody or peptide) and used to formulate nanoparticles encapsulating a drug, these particles exhibit enhanced cellular uptake via receptor-mediated endocytosis. For example, MAL-functionalized nanoparticles conjugated to a tumor-targeting peptide (e.g., RGD for integrin alphavbeta3) show increased uptake and cytotoxicity in cancer cells overexpressing the target receptor compared to non-targeted nanoparticles. The nanoparticles are generally non-toxic to most cell lines at concentrations used for drug delivery (10-200 microg/mL).
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| ln Vivo |
In vivo, PLGA-PEG-MAL-based nanoparticles are used to improve drug delivery and reduce systemic toxicity. In tumor-bearing mouse models, actively targeted nanoparticles prepared with this copolymer show enhanced tumor accumulation (by 2-5 fold) compared to non-targeted controls, due to the EPR effect combined with active targeting. The 50:50 LA:GA ratio provides a degradation half-life of approximately 2-4 weeks, allowing sustained drug release. The maleimide group enables the attachment of targeting moieties post-nanoparticle formation. The PEG block (5.0 kDa) effectively reduces nonspecific protein adsorption (stealth effect) and prolongs circulation time.
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| Enzyme Assay |
Enzyme/receptor binding experiments are not performed directly with this copolymer. However, the conjugation efficiency of the maleimide group can be characterized. To assess maleimide functionality, a standard Ellman's assay is performed: a thiol-containing compound (e.g., cysteine, 2-mercaptoethanol) is incubated with the MAL-terminated polymer at pH 7.0 for 2-4 h at room temperature. The remaining free thiols are quantified by Ellman's reagent (DTNB, 5,5'-dithio-bis-(2-nitrobenzoic acid)) at 412 nm. The degree of substitution (number of MAL groups per polymer chain) can be calculated by NMR or by MALDI-TOF mass spectrometry. For protein binding, the interaction of the polymer with serum proteins can be assessed by incubating the polymer (1 mg/mL) in 50% fetal bovine serum at 37degC for 1-4 h, then centrifuging and analyzing the protein corona by SDS-PAGE or LC-MS/MS.
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| Cell Assay |
To prepare targeted nanoparticles, a targeting ligand (e.g., a thiolated antibody or peptide) is conjugated to the MAL group. The ligand is first reduced to generate free thiols if necessary (using TCEP or DTT). PLGA-PEG-MAL (20 mg) is dissolved in conjugation buffer (PBS, pH 6.5-7.0, with 2 mM EDTA). The thiolated ligand (1-5 mg) is added at a molar ratio of 1:1 to 5:1 (ligand:maleimide). The reaction mixture is incubated at 4degC or room temperature for 2-4 h under nitrogen protection. Unreacted maleimide groups are quenched by adding 5 mM cysteine. The product (PLGA-PEG-ligand) is purified by dialysis (MWCO 10-20 kDa) against water to remove free ligand and byproducts. Conjugation efficiency is confirmed by SDS-PAGE or by measuring the decrease in free thiols using the Ellman's assay. A cellular uptake experiment is then performed as described for V76620. Nanoparticles are formulated by the nanoprecipitation method: the PLGA-PEG-ligand is dissolved in acetone (10 mg/mL) and added dropwise to water under stirring. The solvent is evaporated, and the nanoparticle size is measured by DLS. Fluorescently labeled nanoparticles are used for flow cytometry or confocal imaging as described previously.
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| Animal Protocol |
The in vivo protocol for PLGA-PEG-MAL is similar to that for PLGA-PEG-NH2 (V76620). Female BALB/c nude mice (6-8 weeks, n=6-8 per group) are implanted subcutaneously with 1-5×10⁶ cancer cells. When tumors reach 100-150 mm3, mice are randomized into groups receiving: (1) free drug, (2) non-targeted nanoparticles (PLGA-PEG without MAL-ligand), (3) ligand-conjugated targeted nanoparticles, and (4) vehicle control. The nanoparticles encapsulating a drug are prepared and characterized for drug loading, size, and zeta potential. The formulation is administered intravenously (tail vein) at a dose equivalent to 5-20 mg drug/kg every 3-7 days for a total of 3-4 injections. Tumor volume is measured every 2-3 days, and body weight is recorded. At the end of the study (e.g., day 28), tumors and major organs (liver, kidneys, spleen, lungs, heart) are collected for histology and biodistribution analysis. For pharmacokinetic studies, blood is collected at various time points (0, 1, 2, 4, 6, 12, 24, 48 h) and the concentration of the encapsulated drug is analyzed by HPLC-MS.
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| ADME/Pharmacokinetics |
The pharmacokinetics of the encapsulated drug are determined by the nanoparticle formulation rather than the polymer alone. The PEG block (5 kDa) provides a "stealth" effect, reducing opsonization and clearance by the reticuloendothelial system (RES). The plasma half-life of PLGA-PEG-MAL nanoparticles is significantly longer (typically 4-10 hours) than that of non-PEGylated PLGA nanoparticles (typically <1 hour). The 5.0 kDa PEG molecular weight is within the optimal range for steric stabilization. The polymer is biodegradable; the PLGA block (20 kDa, 50:50 LA:GA) degrades via ester bond hydrolysis over 4-8 weeks in vivo. The maleimide group reacts with thiols under physiological conditions; the resulting thioether bond is stable in the circulation. No specific drug-drug interactions are known.
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| Toxicity/Toxicokinetics |
PLGA-PEG-MAL is generally regarded as biocompatible and biodegradable, similar to PLGA and PEG polymers approved by the FDA for medical applications. Acute toxicity studies in mice (single IV injection of up to 500 mg polymer/kg) show no significant adverse events. Sub-chronic (28-day) repeated dose studies in rats at up to 200 mg/kg/day show no significant target organ toxicity or histopathological changes. The maleimide group is reactive and could potentially react with serum proteins (e.g., albumin) in vivo, but this is generally considered acceptable. No genotoxicity or cardiotoxicity data are available for this specific copolymer. Standard laboratory safety practices (gloves, lab coat, eye protection) should be followed.
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| References |
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| Additional Infomation |
PLGA-PEG-MAL (20kDa-5.0kDa, LA:GA ratio 50:50) is a research-grade copolymer and is not approved for human use as a finished drug product. The maleimide functional group enables efficient conjugation to thiolated biomolecules, making it a valuable tool for the development of actively targeted drug delivery systems. The 50:50 ratio of lactic acid (LA) to glycolic acid (GA) determines the matrix degradation and protein re-release rate: a 50:50 ratio degrades faster (2-4 weeks) than higher LA ratios. The molecular weight of the PLGA block is 20 kDa, and the PEG block is 5.0 kDa. The product is supplied as a solid and should be stored as a pure form at -20degC for 3 years or in solvent at -80degC for 1 year.
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| Related CAS # |
PLGA-PEG-MAL (20kDA-5.0kDA, LA:GA ratio 40:60)
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| Appearance |
White to off-white ointment
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| HS Tariff Code |
2934.99.9001
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| Storage |
Powder -20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month |
| Shipping Condition |
Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)
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| Solubility (In Vitro) |
May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples
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| Solubility (In Vivo) |
Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.
Injection Formulations
Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)(e.g. IP/IV/IM/SC) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). View More
Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] Oral Formulations
Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). View More
Oral Formulation 3: Dissolved in PEG400 (Please use freshly prepared in vivo formulations for optimal results.) |
Calculation results
Working concentration： mg/mL；
Method for preparing DMSO stock solution： mg drug pre-dissolved in μL DMSO (stock solution concentration mg/mL). Please contact us first if the concentration exceeds the DMSO solubility of the batch of drug.
Method for preparing in vivo formulation:：Take μL DMSO stock solution, next add μL PEG300, mix and clarify, next addμL Tween 80, mix and clarify, next add μL ddH2O，mix and clarify.
(1) Please be sure that the solution is clear before the addition of next solvent. Dissolution methods like vortex, ultrasound or warming and heat may be used to aid dissolving.
(2) Be sure to add the solvent(s) in order.
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