Poly(L-lactide)(PLLA) - pharmaceutical grade, Mw:90-280 KDa , CAS No.33135-50-1

CAS: 33135-50-1 Cat. No.: P1521511 Fórmula: -(C₆H₈O₄)n-

GRADE & PURITY Pharmaceutical grade, Mw:90-280 KDa

Storage

Store at 2-8°C,Protected from light

Shipped In

Wet ice

Specifications

Especificaciones y pureza

pharmaceutical grade, Mw:90-280 KDa

Condiciones de almacenamiento de almacenamiento

Store at 2-8°C,Protected from light

Enviado en

Wet ice

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Grado

Pharmaceutical grade

Nombres e identificadores

Isómeros SMILES

CC1C(=O)OC(C(=O)O1)C

CAS alternativo

26161-42-2

Reaxy-Rn

82121

Reaxys-RN_link_address

https://www.reaxys.com/reaxys/secured/hopinto.do?context=S&query=IDE.XRN=82121&ln=

Propiedades químicas y físicas

• Punto de fusión (°C): 180 °C

Application Protocols

• No assay-specific protocols (e.g., WB, IHC, IF, FC) are applicable to this polymeric material.

• General laboratory procedures (literature/practice; not product specifications)

  • Film casting: Dissolve PLLA in an appropriate solvent (e.g., CHCl3), filter, cast onto a leveled substrate, allow slow evaporation under cover, then vacuum-dry to remove residual solvent.
  • Electrospinning: Prepare a homogeneous solution (e.g., DCM:DMF 70:30), load into syringe with blunt needle, adjust voltage/flow/collector distance to achieve bead-free fibers, and dry thoroughly post-collection.
  • Microsphere preparation: Emulsify PLLA solution (in DCM/EA) into an aqueous stabilizer (e.g., PVA) under shear; evaporate solvent under stirring; wash and dry particles. Optimize shear, polymer %, and solvent removal rate for target size distribution.

• Always tailor conditions to molecular weight, desired morphology, and equipment, and follow the SDS for solvent handling.

Biological Roles

• Item-specific (Product Data)

  • Research use note: For research use only.

• Literature/general context (biochemistry; not product specifications)

  • Biodegradation: PLLA hydrolyzes to oligomers and ultimately lactic acid. Enzymatic contributions (e.g., esterases) can augment abiotic hydrolysis under physiological conditions.
  • Metabolic fate: Lactic acid integrates into cellular metabolism—interconverted with pyruvate and funneled into the tricarboxylic acid (TCA) cycle for energy production (biochemical context).
  • Influence of stereochemistry: The isotactic nature of PLLA increases crystallinity, which slows water ingress and enzymatic access, modulating degradation rate relative to amorphous PDLLA.
  • Local microenvironment: During degradation, transient pH decreases can occur in poorly buffered systems due to carboxylic end-group accumulation; this can influence in vitro cell behavior and co-delivered actives.
  • Surface interactions: Protein adsorption and cell attachment to PLLA are affected by surface chemistry and roughness; plasma treatments and peptide grafting are commonly employed to tune biointeractions in research.

• Important note

  • No medical or clinical claims are made. The above roles describe general biochemical pathways relevant to laboratory studies of biodegradable polymers.

Buffer Applications

• Not typically applicable. PLLA is a hydrophobic, water-insoluble polymer and does not function as a buffering agent.
• Practical note: In aqueous formulation studies, external buffer systems (e.g., phosphate, HEPES) are used to control pH while PLLA forms the solid matrix or particulate carrier. Monitor potential acidification during polymer degradation over extended incubations.

Green Alternatives

• Context: While PLLA processing traditionally uses chlorinated solvents (e.g., CHCl3, DCM), greener solvent systems and bio-based polymer alternatives can reduce environmental burden. The suitability depends on required solubility, film quality, and device specifications.

• Greener solvent options for PLLA dissolution (literature; balance performance vs EHS)

  • Ethyl acetate: Bio-derived availability; moderate solvency—often requires warming or longer dissolution times.
  • Anisole: Higher boiling, non-chlorinated; improves film leveling; may need elevated temperature.
  • Cyclic carbonates (e.g., propylene carbonate): Limited solvency for high-MW PLLA but useful as plasticizers or in blends.
  • 2-Methyltetrahydrofuran (2-MeTHF): Mixed reports on solvency; sometimes viable for lower-MW PLLA or blends.

• Alternative materials (when design allows)

  • Poly(ε-caprolactone) (PCL): Lower Tm/Tg; slower biodegradation; dissolves in greener esters/ketones more readily.
  • Poly(butylene succinate) (PBS): Aliphatic polyester with improved processing in non-halogenated solvents; different degradation/mechanics.
  • PLA stereocomplex (PLLA/PDLA blends): Higher Tm, improved thermal resistance; processing considerations differ.

• Trade-offs to consider

  • Solvent power vs safety: Non-halogenated systems may need heat/time and can increase hydrolysis risk.
  • Thermal budget: Greener, higher-boiling solvents may extend exposure above Tg, affecting Mn via transesterification.
  • End-use requirements: Mechanical strength, clarity, and degradation profile may necessitate traditional solvents despite EHS concerns.

Pharmaceutical Uses

• Item-specific (Product Data)

  • Grade: Pharmaceutical grade. No specific pharmacopeial listing or tests are provided for this item; refer to CoA/Spec Sheet.

• Literature/general formulation roles (research context only; not product specifications)

  • Controlled-release matrices: PLLA is widely studied as an excipient matrix for depot systems (e.g., rods, implants) where degradation governs release kinetics.
  • Particulate systems: Microspheres/nanospheres prepared by emulsification–solvent evaporation, spray drying, or nanoprecipitation for lab-scale delivery studies.
  • Device coatings: Research on PLLA coatings for stents or scaffolds to modulate surface properties and release profiles.
  • 3D printing and molding: Filaments/pellets processed into prototype devices; mechanical and degradation behavior tuned by crystallinity and molecular weight.

• Quality considerations for formulation development (general)

  • Molecular weight/dispersity: Control mechanical strength and degradation rate.
  • Residuals and extractables: Low residual monomer/solvent and tight elemental impurity controls reduce leachables risk.
  • Sterilization compatibility: Ethylene oxide and gamma are commonly explored; each can affect Mn and properties—validate per application.

• Compliance note

  • This product is supplied for research use only. Suitability for clinical or commercial manufacturing requires additional qualification and regulatory assessment beyond the scope of this listing.

Physical Properties

• Item-specific (Product Data)

  • Appearance: Not specified for this item; refer to CoA/Spec Sheet.

• Literature/general properties (not specifications; vary with molecular weight, tacticity, and processing)

  • Thermal transitions (PLLA):
    • Glass transition, Tg: ~55–65 °C (literature)
    • Melting temperature, Tm: ~165–180 °C for semi-crystalline PLLA (literature)
    • Decomposition onset: typically >250 °C under inert atmosphere (literature)
  • Density: ~1.24–1.27 g/cm3 at 25 °C (literature)
  • Solubility: Insoluble in water; soluble in chlorinated solvents (e.g., CHCl3, CH2Cl2), dioxane; variably soluble in THF, acetone, ethyl acetate (often with warming) (literature)
  • Hygroscopicity/Hydrolysis: Susceptible to hydrolytic degradation; moisture accelerates chain scission (literature)
  • Optical activity: Derived from L-lactide; exhibits optical activity; specific rotation depends on chain length and crystallinity (literature)
  • Film/fiber formation: Readily cast into films or spun into fibers from suitable solvents (literature)

• Notes for practitioners

  • Reported property ranges depend strongly on Mn/Mw, crystallinity, and processing history. Always consult the item’s CoA for measured values (e.g., intrinsic viscosity, Mn/Mw, residual monomer), which are Not specified for this item; refer to CoA/Spec Sheet.

Quality and Grades

• Item-specific (Product Data)

  • Grade/Purity: Pharmaceutical grade.
  • Item-specific analytical details (e.g., Mn/Mw/Ð, residual monomer, endotoxin, metals, UV cutoff, stabilizers): Not specified for this item; refer to CoA/Spec Sheet.

• What “Pharmaceutical grade” implies (general guidance)

  • Intended for use as an excipient or material in research related to drug delivery/medical device development (not for human use unless further qualified). Typically associated with tighter controls on bioburden, endotoxin, residual solvents/monomer, and elemental impurities compared with technical grades. Exact acceptance criteria are manufacturer-specific; defer to the CoA/SDS.

• Practical considerations for PLLA quality control (general, not item-specific):

  • Molecular characteristics: Mn, Mw, and dispersity (Ð) critically influence melt viscosity, mechanical strength, degradation profile, and processing windows.
  • Chemical purity: Low residual lactide/solvent and limited cyclic oligomers help control crystallization and reduce extractables/leachables.
  • Optical purity: High enantiomeric purity (L-content) promotes higher crystallinity and Tm; racemization control during synthesis is important.
  • Stabilization: Some PLLAs are supplied with antioxidants or end-group cappers; if present, these should be disclosed on the CoA. For this item: Not specified for this item; refer to CoA/Spec Sheet.

• Documentation

  • For regulatory or QA workflows, request CoA, TSE/BSE statements, elemental impurity assessment (per ICH Q3D), and residual solvent summary (ICH Q3C).

Reaction and Applications

• Item-specific (Product Data)

  • Manufacturer Applications: Not specified for this item; refer to CoA/Spec Sheet.

• Literature/general applications of PLLA (not product specifications)

  • Materials and devices: Films, fibers, 3D-printed objects, and resorbable prototypes for laboratory evaluation. Its semi-crystalline nature provides higher modulus than PDLLA.
  • Drug delivery research: Matrix systems, microspheres/nanospheres via emulsification–solvent evaporation, and coatings for controlled release studies (research use only).
  • Tissue engineering research: Porous scaffolds via salt leaching, thermally induced phase separation, or electrospinning; degradation to lactic acid enables bioresorbability studies.
  • Composites: Reinforcement with ceramics (e.g., HA, TCP) or fillers (e.g., CNTs) to tailor mechanics and degradation.

• Processing-related reactions (polymer chemistry context)

  • Hydrolysis: Ester bonds undergo bulk and surface hydrolysis; rate increases with temperature, moisture, and pH extremes.
  • Alcoholysis/Transesterification: Can occur during melt processing or in polar aprotic solvents at elevated temperature; controlled end-capping possible with alcohols.
  • Crystallization: Cold crystallization on heating above Tg; crystallinity tuned by thermal history and nucleating agents.

• Practical tips

  • Keep material dry; pre-dry under vacuum (e.g., 30–60 °C) prior to melt or solution processing to preserve Mn.
  • Use inhibited, dry solvents and low-basicity conditions to limit chain scission.
  • Control cooling rate and annealing to adjust crystallinity, Tm, and mechanical properties.

Reaction Conditions

• Item-specific (Product Data)

  • No reaction conditions are specified for this item; refer to CoA/Spec Sheet.

• Literature/general processing and modification conditions (not product specifications)

  • Solution processing: 1–10% w/v in CHCl3, DCM, or dioxane at 20–40 °C with stirring until clear; water-free conditions minimize hydrolysis. For greener systems (e.g., ethyl acetate), warming (40–60 °C) and longer times are often needed.
  • Electrospinning: 5–20% w/v solutions; voltage 10–25 kV; flow 0.2–1.5 mL/h; 10–20 cm tip-to-collector distance. Optimize per solvent/Mn.
  • Melt processing: Dry under vacuum (e.g., 30–60 °C, 6–24 h). Extrusion/injection typically at 170–200 °C barrel temps with low residence time to limit degradation. Nitrogen purge beneficial.
  • Annealing/crystallization: 80–130 °C for 10–60 min to increase crystallinity; monitor Tm/Tc via DSC.
  • Hydrolysis studies: Incubate in buffered media (e.g., PBS, pH 7.4) at 37 °C; track mass loss/Mn by GPC and pH changes over weeks to months.
  • Surface modification: Mild NaOH or ethanolamine treatments (minutes) to increase surface –OH/–COO− density; follow with coupling chemistries. Balance against bulk property loss.

• Expected outcomes (typical)

  • Increased crystallinity via annealing raises modulus and heat resistance; solution-cast films exhibit lower crystallinity unless post-annealed. Hydrolysis accelerates with higher temperature, lower pH or higher pH, and lower Mn.

Safety and Handling

• Item-specific (Product Data)

  • GHS classification / Signal word / H-Statements / Pictograms: Not specified for this item; refer to SDS.
  • Storage: Store at 2–8 °C, protected from light (Product Data). Shipped on wet ice (Product Data).

• General safety guidance for PLLA (literature/practice; not a substitute for the SDS)

  • Hazards: Generally regarded as low-toxicity polymer; principal risks are dust generation (mechanical irritation), solvent exposure during processing, and thermal decomposition products at elevated temperature.
  • Incompatibilities: Avoid strong bases and strong acids, especially at elevated temperature or in solution, which catalyze ester hydrolysis. Avoid prolonged exposure to moisture.
  • Special risks: Moisture-induced depolymerization (chain scission) can alter molecular weight and performance. Overheating above decomposition temperatures can release irritating fumes (e.g., lactide, acetaldehyde; literature).
  • PPE: Lab coat, safety glasses, appropriate chemical-resistant gloves matched to processing solvent. Use dust mask/respirator if handling powders that can become airborne. Employ fume hood for all solution processing.
  • First aid (overview):
    • Inhalation of dust: Move to fresh air; seek medical advice if symptoms persist.
    • Skin/eye contact with solutions: Rinse with water for ≥15 min; remove contaminated clothing; obtain medical attention as appropriate (solvent-driven irritation likely).
  • Fire safety: Combustible solid. Use water spray, dry chemical, CO2, or foam. Thermal decomposition may produce CO/CO2 and irritating vapors. Maintain good housekeeping to minimize combustible dust.

Solvent Selection

• Role: PLLA is a solid polymer; solvent choice governs dissolution, film casting, fiber spinning, and coating.

• Literature/general solvent profile (not specifications)

  • Water: Insoluble.
  • Good solvents (room temperature to mild warming): Chloroform, dichloromethane, 1,4-dioxane.
  • Conditional solvents (often require warming, higher MW lowers solubility): THF, acetone, ethyl acetate, anisole; DMF/DMSO sometimes with heat but risk of transesterification at elevated temps.
  • Nonsolvents/precipitants: Alcohols (e.g., methanol, ethanol), hexanes, heptane; used for phase inversion or precipitation.

• Practical selection tips

  • For clean film casting: CHCl3 or DCM provide rapid dissolution and fast evaporation; dioxane for slower evaporation and improved film uniformity.
  • For greener systems: Ethyl acetate or anisole can work at moderate temperatures; balance viscosity and evaporation rate.
  • For electrospinning: CHCl3:DMF or DCM:DMF blends tune conductivity and jet stability; optimize ratio empirically.
  • Moisture caution: Dry solvents thoroughly; trace water accelerates hydrolysis and reduces molecular weight during processing.

• Comparison (literature-based, typical behavior)

  • Chloroform: Excellent solvency; slower drying; halogenated.
  • DCM: Excellent solvency; very fast drying; halogenated, volatile.
  • Dioxane: Good solvency; miscible with many additives; slower evaporation.
  • Ethyl acetate: Safer profile; may require warming/higher time for full dissolution depending on MW.
  • THF: Moderate solvency; peroxide former—monitor and inhibit as needed.

Storage and Reconstitution

• Item-specific (Product Data)

  • Storage conditions: Store at 2–8 °C, protected from light.
  • Shipped on: Wet ice.

• General handling guidance (literature/practice; not product specifications)

  • Moisture control: Keep tightly sealed with desiccant. Dry under vacuum (e.g., 30–60 °C, 6–24 h) before melt or solution processing to minimize hydrolysis and preserve molecular weight.
  • Light/heat: Protect from prolonged light and elevated temperatures that can catalyze degradation or racemization.
  • Solution preparation: Use dry, inhibitor-checked solvents; add polymer gradually with stirring. Gentle warming (≤40 °C for chlorinated solvents; higher for greener alternatives) can aid dissolution. Avoid strong bases/acids during dissolution.
  • Filtration: For dust/gel removal, filter solutions through solvent-compatible membranes (e.g., PTFE) of appropriate pore size.
  • Storage of solutions: Prefer fresh use. If necessary, store at 2–8 °C in airtight containers with minimal headspace; expect gradual viscosity decrease over time due to chain scission.
  • Freeze–thaw: Not applicable to the solid; avoid freezing polymer solutions that may phase-separate or trap moisture on thaw.

• Shelf-life notes

  • Molecular weight drifts with moisture/temperature exposure. For item-specific shelf-life and Mn retention data: Not specified for this item; refer to CoA/Spec Sheet.

Structure and Identity

• Item-specific (Product Data)

  • Product name: Poly(L-lactide) (PLLA)
  • CAS: 33135-50-1
  • Grade: Pharmaceutical grade
  • SMILES: Not specified for this item; refer to CoA/Spec Sheet.
  • InChIKey: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular formula: Not specified for this item; refer to CoA/Spec Sheet. (Note: polymers are represented by repeat units rather than a fixed molecular formula.)
  • Molecular weight: Not specified for this item; refer to CoA/Spec Sheet. (Note: polymers are polydisperse; Mn/Mw/Ð should be consulted on the CoA.)

• Literature/general description (for context; not product specification)

  • Polymer type: Semi-crystalline, aliphatic polyester derived from the L-enantiomer of lactic acid.
  • Repeat unit: –[–O–CH(CH3)–CO–]–n (commonly written as (C3H4O2)n)
  • Stereochemistry: Isotactic sequence from L-lactide leads to higher crystallinity relative to PDLA/PDLLA blends.
  • Structural features: Backbone composed of alternating ester linkages and methine carbons bearing a methyl substituent; absence of aromatic rings or heterocycles.
  • 2D description: A linear chain of ester-connected lactic units; each repeat features a chiral center (S configuration for PLLA), a carbonyl (C=O) adjacent to an ether oxygen, and a pendant methyl group on every other carbon.

• Identifiers

  • PubChem CID: 7272 (general PLLA entry; for reference only)

Synthetic Utility

• Context: PLLA is a finished polymer but is also a platform for further chemical modification and for studying polymerization mechanisms.

• Literature/general transformations (not product specifications)

  • End-group modification: Hydroxyl- or carboxyl-terminated PLLA can be functionalized via esterification, carbodiimide coupling, or click reactions (after suitable handle installation) to attach dyes, peptides, or initiators.
  • Block copolymers: Use PLLA as a macroinitiator or macro-CTA to assemble PLA-based block copolymers (e.g., PLLA-b-PEG, PLLA-b-PCL) for tuning hydrophilicity and mechanics.
  • Grafting: Surface-initiated polymerizations on PLLA films/fibers (e.g., SI-ATRP/SI-RAFT after primer deposition) enable interfacial property control.
  • Blend compatibilization: Reactive blending with polyesters or elastomers using chain extenders (e.g., epoxides, isocyanates) to adjust rheology and toughness.

• Polymerization background (for reference)

  • PLLA is typically prepared by ring-opening polymerization (ROP) of L-lactide using tin(II) 2-ethylhexanoate, aluminum or zinc catalysts, or organocatalysts (e.g., TBD, DBU) under dry, anhydrous conditions.

• Practical utility in the lab

  • As a scaffold: Castable matrices for immobilizing reagents, creating semi-permeable barriers, or fabricating microfluidic components.
  • As a degradable handle: PLLA segments incorporated into conjugates that are cleavable under aqueous or basic conditions to release attached moieties.

Target Specificity

• Not applicable. This product is a synthetic polymer material, not an affinity reagent or biologic. No antigen/epitope specificity, clone, or isotype applies.
• For application-specific interactions (e.g., protein adsorption), consult surface chemistry literature rather than immunoassay specifications.