GMP Plasmid DNA

GMP Plasmid DNA, Minicircle & Nanoplasmid Manufacturing

Design → GMP, without detours. A microbial-first platform that manufactures plasmid DNA (pDNA), minicircle DNA, and small-backbone “nanoplasmid-style” vectors with ultra-low endotoxin, high supercoiled content, and inspector-ready documentation—from feasibility to commercial supply.

Executive overview

Plasmid DNA is the unsung fulcrum of modern cell and gene therapy. It seeds everything: AAV and lentiviral packaging, CRISPR/Cas components, mRNA templates, DNA vaccines, and next-generation gene delivery. Yet a surprising number of programmes stall not in the clinic, but in the reactor and the column—when supercoiled content falls, endotoxin drifts, host contamination appears, or the dossier cannot explain how critical attributes are held.

Mika Biologics solves this with a disciplined, microbial-native stack. We manufacture R&D → GMP pDNA, minicircle DNA (backbone-free expression cassettes), and small-backbone plasmids (“nanoplasmids”) for CGT customers who need consistent topological purity, clean impurity stories, and reliable timelines. Our upstream is E. coli engineered for stability and copy number without antibiotic crutches; our downstream is alkaline lysis → clarification → AEX capture → HCIC or membrane polishing → UF/DF to formulation—tuned to deliver high % supercoiled, ultra-low endotoxin, and tight HCP/host-DNA/RNA specifications. Release methods (qPCR/ddPCR, CE/CGE/HPLC, rFC/LAL, bioburden/sterility) flow through an ALCOA+ digital spine to generate CoA/CoC sets that read cleanly.

This page lays out the complete offering: platforms, control strategies, analytical fingerprints, antibiotic-free selection options, minicircle/nanoplasmid workflows, PPQ/CPV, and tech-transfer SLAs. It is written for teams who want precision without ceremony and speed without shortcuts.

Mika Biologics, CDMO for Microbial projects

What we deliver

  • Grades & scales
    • R&D/Discovery (grams-scale), GMP-like (to support tox/engineering), and full GMP (IND/BLA-supportive starting material).
    • Reactors from 2–10 L (development) to 50–200 L (GMP), with routes beyond where programme demands.
  • Vector classes
    • Standard pDNA: high-copy and medium-copy backbones with antibiotic or antibiotic-free selection.
    • Minicircle DNA: recombination-excised expression cassettes with minimal bacterial sequence.
    • Small-backbone “nanoplasmid-style” vectors: proprietary or proprietary-like minimal backbones with optimised origin and selection heredity.
  • Process & quality outcomes
    • High supercoiled fraction (SC) with tightly bounded open-circular (OC) and linear species.
    • Ultra-low endotoxin, low residual RNA, low HCP, low host genomic DNA (hgDNA), residual salt/solvent in control.
    • Formulations for AAV/Lenti plasmids (helper/rep-cap/GOI), CRISPR plasmids, IVT templates, DNA vaccines.
  • Documentation & release
    • CoA/CoC, full batch records, raw-data attachments, and tech-transfer SLAs.
    • Release/QC: identity (NGS or Sanger + restriction), %SC by CE/CGE/HPLC, A260/280/320, qPCR/ddPCR residuals, rFC/LAL endotoxin, bioburden/sterility where applicable.
    • Stability packages and storage/handling IFUs (−20 °C / −80 °C; thaw-mix policies; shear guidance).

QTPP → CQA → CPP: the control story on one page

We start each programme with an explicit, shared map.

  • QTPP (examples): vector type and size (bp), intended use (AAV rep-cap/helper, lentiviral transfer/helper, CRISPR, IVT), grade (R&D vs GMP), presentation (concentrate vs ready-use), storage (−20/−80 °C), target dose (mg/lot), sequence confirmation depth (NGS vs targeted), and impurity limits (endotoxin EU/mg, %RNA, %HCP, hgDNA ng/mg, %SC).
  • CQAs: identity (full-length sequence, restriction profile), % supercoiled, OC/linear %, endotoxin, residual RNA, hgDNA (host chromosomal DNA), HCP, residual salts/solvents, antibiotics absent (if antibiotic-free), topology under shear, bioburden/sterility (as required), and concentration/volume accuracy.
  • CPPs: host genotype and selection architecture; fermentation temperature/DO/pH and feed composition; copy-number timing; alkaline lysis conditions (SDS/NaOH time and temperature windows); neutralisation kinetics; clarification shear; AEX load/conductivity/pH; HCIC/membrane load and elution; UF/DF flux/ΔP; mixing protocols; filter materials and hold-up; fill temperature and time-in-solution.

Everything else—DoE plans, scale-down fidelity, PPQ acceptance, and CPV tags—flows from this sheet.

Platform architecture

Vector & host engineering

  • Backbone and ori: high-copy (e.g., ColE1-derivatives) for yield; medium-copy to enhance stability with very large inserts or toxic payloads; small-backbone designs for nanoplasmid-style vectors to reduce bacterial sequence burden.
  • Antibiotic-free selection:
    • Operator-repressor titration (ORT) or analogous systems that couple plasmid maintenance to essential gene expression.
    • Auxotrophy complementation (e.g., diaminopimelate or thymidine/thyA systems) to eliminate antibiotic resistance markers.
    • Toxin–antitoxin balanced designs used only in development; for GMP we prefer chromosomal complementation or ORT-like selection that regulators accept readily.
  • Dam/Dcm & methylation: host methylation states configured per downstream need (e.g., restriction sensitivity, CpG patterns affecting in vitro transcription yield).
  • Genetic stability: recA- / endA- strains, prophage-free, IS-element-managed hosts; protect repeats and strong secondary structures by temperature and feed tuning.

Upstream (USP): fermentation that yields without drift

  • Batch/fed-batch in defined or semi-defined media; controlled induction of copy number (temperature or feed-linked) to limit burden until biomass is banked.
  • Tight pH/DO windows; antifoam policies that don’t harm downstream binding; osmolality control to limit lysis fragility.
  • IPC: biomass, copy-number proxies (qPCR), plasmid retention (selective plating), endotoxin sentinel (media/raws), and off-gas analytics.
  • Seed trains from MCB/WCB with identity checks and passage limits; antibiotic-free selection pressure maintained as per architecture.

Lysis & clarification: protecting topology

  • Alkaline lysis with time-temperature-mixing tightly controlled; SDS/NaOH exposure kept within validated envelope to avoid nicking.
  • Neutralisation staged to favour chromosomal aggregation and plasmid retention; cooling ramp controlled.
  • Clarification via depth filtration and/or centrifugation; shear exposure indexed; RNase-free approaches preferred (or nuclease qualified and cleared) to minimize residual enzyme risk.
  • Primary capture pre-conditioning (conductivity, pH) designed to land precisely on AEX binding curve.

Capture & polishing: AEX → HCIC / membranes → UF/DF

  • Anion-exchange capture (AEX) on resins or membrane monoliths sized to plasmid hydrodynamics; load density and residence time tuned to %SC retention and host DNA removal.
  • HCIC (hydrophobic charge-induction chromatography) as a powerful orthogonal polish: binds nucleic acids and contaminants under one charge state and elutes under another—very effective for RNA and endotoxin reduction without excessive shear.
  • Membrane adsorbers (AEX or hybrid) to target endotoxin late, limiting exposure of the supercoiled fraction to harsh conditions.
  • UF/DF: staged concentration/diafiltration with low shear; membranes selected for DNA recovery and extractable control; conductivity/pH landed to formulation spec.
  • Optional endotoxin phase-partition (e.g., amphiphile-assisted) used in development only; for GMP, we prefer resin/membrane designs that avoid introducing complex reagents.
Mika Biologics, Bioreactor image

Formulation, filtration & fill

  • Buffers: low-ionic-strength Tris/EDTA alternatives or nuclease-safe formulations as per downstream; divalent cations controlled; no chelators if the use requires Mg²⁺ presence (e.g., IVT).
  • Sterile filtration (0.22 µm) when compatible with viscosity and concentration; if not (very high-concentration DNA), we use closed aseptic processing with validated bioburden controls.
  • Fill in Grade A isolators (Grade B background) into vials or bottles; time-in-solution and temperature limits enforced; nitrogen overlay where oxygen uptake matters.
  • Packaging: DNA-safe resins; headspace O₂ control for long holds; labels with thaw-mix guidance and shear cautions.

Minicircle DNA: backbone-free expression cassettes

Why minicircle? Removing bacterial backbones improves expression and safety profiles for some applications (reduced CpG/TLR9 activation, smaller size for electroporation, higher transfection efficiency).

Manufacturing approach

  • In vivo recombination (e.g., site-specific recombinase induction) to excise backbone → minicircle + backbone circle.
  • Backbone depletion by size/charge separation (AEX/HCIC) and selective nuclease treatment that spares minicircle.
  • Analytical controls: % minicircle, residual parental plasmid/backbone (< acceptance), % supercoiled minicircle, residual recombinase/nucleases (if used), sequence confirmation (NGS or tiled Sanger).
  • Yield management: develop a recombination window that maximises conversion before lysis/instability; host burden reduced by temperature/DO control.

Small-backbone plasmids

Why small-backbone? Minimal bacterial sequence with stable ori/selection achieves high expression and packaging performance while maintaining standard plasmid handling.

Manufacturing approach

  • Host–vector pairing tuned to copy and stability; antibiotic-free selection preferred;
  • DSP identical in principle to pDNA but more efficient RNA/contaminant removal due to backbone design;
  • Analytics: same as pDNA, with backbone-specific qPCRs to verify integrity; often higher %SC achieved at equivalent downstream conditions.

Analytical & QC: what goes on the CoA (illustrative panel)

Identity & integrity

  • Full-length sequencing (NGS consensus vs reference) or tiled Sanger + restriction/linearisation profile.
  • Topology: % supercoiled, OC, linear by capillary gel electrophoresis (CGE) / CE-LIF, AEX-HPLC, or CGE-HPLC hybrids; acceptance bands pre-agreed.
  • Concentration: A260 with 320-nm correction; qPCR/ddPCR absolute quant.

Impurities & safety

  • Endotoxin by rFC (recombinant factor C) or compendial LAL with full method suitability (inhibition/enhancement controls); report EU/mg.
  • Residual RNA by HPLC profile or specific dyes; hgDNA by qPCR/ddPCR (host-specific assays; ng/mg); HCP by ELISA (host-specific).
  • Residual salts/solvents (e.g., isopropanol) by conductivity/GC; residual detergents where used; antibiotics “not detected” for antibiotic-free builds.
  • Bioburden/sterility as per grade and route (sterility when aseptic processing substitutes for filtration).
  • Appearance/pH/conductivity in band.

Function-adjacent (optional)

  • In vitro transcription (IVT) yield for template plasmids.
  • Restriction/endonuclease sensitivity (methylation state) where downstream demands it.

Documentation

  • CoA with method references; CoC alignment to client specs; sequence map & annotations; stability timepoints; traceability (MCB/WCB lot, resin lots, membrane lots).

Stability, storage & handling

  • Storage: −20 °C or −80 °C (grade-dependent), aliquoted to limit freeze–thaw cycles; lyo exploration where programme benefits are real.
  • Stability studies: real-time and accelerated arms; %SC drift, endotoxin, residuals, and concentration; shear challenge (vortex/pipette cycles) to simulate handling.
  • In-use: thaw time limits, gentle inversion policy (no high-g vortex), low-binding plastics; do not push through narrow needles at high speed unless validated.

Process characterization, PPQ & CPV

  • Scale-down models replicate mixing time, shear spectrum, lysis kinetics, AEX/HCIC residence time/load, and UF/DF flux/ΔP; bias to scale documented.
  • DoE identifies robust islands: lysis time/temperature vs %SC; AEX pH/conductivity vs hgDNA removal; HCIC load vs RNA reduction; UF/DF flux vs recovery.
  • PPQ: three consecutive lots at commercial scale with release windows reflecting real capability (Cp/Cpk).
  • CPV dashboards: historian tags (fermentation temp/DO, lysis timers, AEX conductograms, column ΔP, UF/DF flux, fill temp/time-in-solution) plotted against %SC, endotoxin, residuals—alerts fire before CQAs move.

Antibiotic-free architectures

  • Rationale: eliminating antibiotic resistance markers simplifies filings for viral vector manufacturers and reduces risk of trace antibiotic carryover.
  • Options: ORT-like repression, chromosomal complementation of essential genes, balanced partition systems with non-antibiotic selection pressure.
  • Controls: absence-of-antibiotic assays; plasmid retention under non-selective conditions during holds; sequence confirmations of selection locus.
  • Impact: lower regulatory friction, easier tech transfer to viral vector facilities, and cleaner impurity narratives.

Tech transfer SLAs

  1. Intake: vector maps (GenBank), intended use, target specs, historical CQA data, preferred assays, and raw materials (e.g., proprietary resins).
  2. Bridging: side-by-side runs (where possible) and method transpositions; tolerance windows for bias/precision; report with proposed SOPs.
  3. Qualification/validation: phase-appropriate; we avoid over-validating early and under-validating at PPQ.
  4. Ownership: versioned SOPs in our QMS; reagent lifecycle plans and alternates pre-qualified to blunt supply shocks.
  5. Timelines: milestone-based (seed and media readiness, lysis/clarification feasibility, AEX lock, HCIC/membrane lock, UF/DF lock, analytics transfer, engineering lot, GMP lot).

Regulatory & documentation posture

  • Starting material doctrine: for most CGT programmes, plasmids are regulated as starting materials with GMP expectations scaled to risk; we prepare auditable packages that map the control strategy to CQAs and show PPQ/CPV in place.
  • Raw materials: animal-free/TSE-BSE statements, microbial specifications, CoAs; resin/membrane lifecycle and cleaning validation (if reusable).
  • Change control & comparability: decision trees define minor vs major changes; bridging lots and analytical matrices pre-agreed to avoid ad-hoc debates.
  • Data integrity: eBatch/LIMS with ALCOA+, audit trails, instrument IDs, attached chromatograms/electropherograms, and one-click APR/PQR exports.

Case-style patterns

  • AAV triple-plasmid set (rep-cap/helper/GOI): antibiotic-free selection on all three; AEX + HCIC train; rFC ≤ acceptance; %SC ≥ tight band across set; sequence confirmation by NGS; IVT template variant qualified for high yield.
  • CRISPR HDR donor minicircle: in vivo recombination window tuned; backbone depletion with HCIC + nuclease; parental residual below LOQ; %SC minicircle high; improved electroporation performance vs parental.
  • Small-backbone vector for LV: medium-copy ori; ORT-style selection; DSP simplified; consistently higher %SC than legacy; sterile filtration feasible at target concentration.

How this offering cross-sells your stack

  • LBP / Endotoxin-Free / Phage / VLPs naturally connect into Veterinary & Animal Health for clients who translate gene tools to animal markets.
  • Synthetic Biology Tools & Endotoxin-Free underpins Diagnostics & IVD Enzymes, reinforcing credibility with enzyme OEMs who also need pDNA templates.
  • Fungal & Yeast / Cell-Free / Rare Biologics clients routinely need plasmids/minicircles for expression and prototyping—shared analytics and fill-finish compress calendars.

Inter-page guidance (internal links to keep journeys short)

  • Analytical & QC for Microbial Biologics for SEC-MALS/LC-MS, rFC/LAL, method transfer SLAs, and sample CoAs.
  • Formulation & Aseptic Fill-Finish (Grade A Isolators) for sterile filtration alternatives, CCI, and presentation.
  • Process Characterization, PPQ & CPV for scale-down, PPQ acceptance, and dashboards.
  • Engineered Probiotics (LBP) GMP when programmes fold DNA work into live chassis.
  • Bacteriocins/Phage/OMVs & Advanced Yeast Glycoengineering for adjacent microbial modalities.

FAQ (selected)

Can you guarantee a specific %SC at GMP?
We commit to a banded acceptance defined during development (CGE/HPLC), then prove capability in engineering lots and PPQ. We also define handling envelopes (no harsh vortexing; gentle mixing) so %SC is preserved post-release.

How low is “ultra-low endotoxin”?
We set EU/mg limits aligned to your application (e.g., AAV packaging, IVT, vaccine). The control strategy blends host/media selection, AEX/HCIC/membrane steps, and method suitability on rFC/LAL so the number is credible, not optimistic.

Do you use RNase?
Where possible, we avoid adding nuclease; if used, the enzyme is qualified and cleared with residual assays. We also offer nuclease-free RNA reduction based on HCIC and selective precipitation.

Can you run fully antibiotic-free selection?
Yes. We offer ORT-like, chromosomal complementation, and other non-antibiotic systems, then document “antibiotic absent” on CoA with appropriate analytical coverage.

What sequence confirmation depth do you provide?
NGS consensus vs reference for GMP; for R&D, tiled Sanger + restriction is available. For critical regions (ITRs, LTRs, promoters), we add coverage emphasis and independent confirmatory primers.

Can you deliver “sterile” pDNA?
If sterile filtration is compatible, we filter; otherwise we fill under closed aseptic conditions and release on sterility (compendial) and bioburden while explaining filtration infeasibility.

Do you support high-viscosity fills?
Yes. We adapt tubing, pump type, and needle gauges; fill temperatures controlled; time-in-solution bounded; viscosity measured and tied to fill CV.

What are typical timelines?
Programme-dependent. We structure milestones (tech transfer → engineering lot → GMP lot), publish acceptance gates for each, and keep buffers around PPQ and stability starts so filings aren’t held hostage by paperwork.

Ready to move plasmids from “works” to “works every time”?

Send your vector maps, intended use, target specs, and lot size. We’ll return a plan—seed to PPQ—that locks %SC, endotoxin, and residuals into ranges reviewers accept and operators can execute.

Email our team at info@mikabiologics.com