Marine Drugs Submission Guide: MDPI Process (2026)

Marine Drugs is not a marine-flavored version of a general natural-products journal. It is a chemistry journal with a hard requirement that the molecule be defined. MDPI built it around the discovery, characterization, and pharmacology of biologically active compounds from marine habitats: algae, sponges, corals, marine microorganisms, invertebrates, fish, and mangroves. The editorial question is not whether the bioactivity is exciting. It is whether the chemistry is finished and whether the marine origin is doing real work.

Two consequences matter most. First, the journal is section-based, organized around marine pharmacology, marine natural-product chemistry, structural studies on marine natural products, and marine biotechnology for drug discovery. Scope fit is judged against a specific section, not a vague "is this about the ocean" bar. Second, the pre-check and the structural-chemistry reviewers treat the spectroscopic dataset as the evidence, not as decoration. A paper claiming a new compound without the full NMR and HRMS package is treated as unverifiable, regardless of how good the activity data look.

The unusual upside: because the soundness-based model rewards complete, chemically defined work, a clean isolation-and-characterization paper on a modestly active compound is publishable here even when it would be too incremental for a selectivity-driven title. The journal also runs structure-elucidation special issues that explicitly welcome modern analytical approaches, including advanced NMR, mass-spectrometry-based metabolomics, computational shift prediction, and chiroptical methods, so a methodologically careful structural paper has a natural home.

The core fit for most submissions is the original research paper reporting one or more new marine natural products with their isolation, structure elucidation, and bioactivity. It works best when each compound is defined, the spectra are supplied, and the marine angle is the actual subject.

Ask these questions before you submit:

• is the bioactive entity a defined, isolated molecule, or is it still a crude extract or a partially purified fraction?
• does every new structure come with original 1H, 13C, 2D NMR and HRMS in the supplementary files?
• would the chemistry change if the organism were terrestrial, or is "marine" just a label?
• does the work sit inside marine pharmacology or marine natural-product chemistry, or has it drifted into general natural products?

If the answers are uncertain, the chemistry-completeness problem is usually more important than the bioactivity problem.

The pre-check editor is answering a short list of questions fast, and for this journal the list is unusually chemistry-heavy.

On scope, the editor asks whether the manuscript belongs in a marine-compounds journal and in which section. If the marine relevance is thin or the work is really general phytochemistry, the paper is redirected or returned. On chemical definition, the question is whether the active entity is a characterized molecule. A study that reports activity from an undefined extract, with no isolation and no structure, reads as out of scope for a journal whose remit is chemically defined marine compounds.

On structural evidence, the editor and the assigned reviewers check whether each new compound carries the full spectroscopic dataset and whether the assignment is internally consistent. This is where most reviewer-stage friction concentrates: marine natural products are structurally complex, and the field's own audits have found that a meaningful fraction of NMR-and-MS-elucidated structures contain assignment errors, so reviewers expect the raw spectra to be checkable.

On integrity, the editor confirms ethics, biological-material sourcing, and data availability are in order; MDPI runs integrity and plagiarism checks at pre-check. On completeness, the editor looks for the declarations block, because a manuscript missing Author Contributions, Funding, or Conflicts of Interest reads as not ready even when the science is fine.

Manuscript structure: Marine Drugs expects a defined section set: Abstract, Keywords, Introduction, Results, Discussion, Materials and Methods, Conclusions, plus the declarations block. Research papers need a structured abstract of around 200 words, and the journal also accepts short notes and reviews. The abstract is the first thing the pre-check editor reads, so the new compound, the marine source, and the headline bioactivity all need to be visible there.

Structure elucidation and data readiness: This is the part of the package that decides reviewer-stage outcomes. For every new compound, supply original 1H, 13C, and 2D NMR spectra plus HRMS, with purity confirmed by an LCMS chromatogram or elemental analysis, and prepare the NMR data tables according to the ACS preparation standard. Provide full experimental detail so the isolation and the characterization can be reproduced.

Where you assign absolute configuration, supply the supporting evidence (single-crystal X-ray, electronic circular dichroism, computational shift comparison, or Mosher analysis), because a configuration asserted without it is a predictable reviewer query.

Dereplication and novelty: Confirm the compound is new before you frame the paper around novelty. A literature and database check (the MarinLit database is the field standard) protects against the most demoralizing rejection in this field, which is reporting a "new" metabolite that turns out to be a known compound from a different source. State the dereplication step explicitly in the methods.

Declarations and ethics: Draft the Author Contributions (by initials), Funding, Data Availability, and Conflicts of Interest statements before you upload, plus any biological-material collection and sourcing statements where field collection of marine organisms is involved. These are pre-check gates at MDPI, not post-acceptance paperwork.

Graphical abstract and supplementary structural assets: A graphical abstract is optional but common; for this journal it usually shows the new structure or the structure-activity relationship rather than a generic schematic, and if supplied it should be a high-resolution PNG, JPEG, or TIFF.

The supplementary file is where the original NMR and HRMS spectra, dose-response bioassay curves, and any X-ray or chromatographic purity data belong, since reviewers verifying a structure elucidation read the supplement as carefully as the main text. ORCID is expected for the submitting author, and the system will ask for suggested reviewers.

In our pre-submission review work with Marine Drugs manuscripts, four failure patterns generate the most consistent pre-check returns and structural-chemistry reviewer friction, and each is testable against your own draft before you upload.

Across our marine natural-products pre-submission reviews, the pattern that surprises authors most is that strong bioactivity numbers do not rescue an incomplete chemistry package. Marine Drugs is a chemistry journal first, so the manuscripts that get returned fastest are rarely the ones with weak activity.

They split cleanly along four lines: the active entity is undefined, the structure is unsupported by spectra, the marine angle is cosmetic, or the scope has drifted out of marine chemistry. Manuscripts coming through pre-submission review for Marine Drugs map onto these four failure patterns.

Crude-extract bioactivity with no isolated, characterized compound

The pattern: activity without a defined molecule. The single most common pattern we see is a manuscript that reports promising activity from a crude extract or a partially purified fraction, with no isolated molecule and no structure. The bioassay dose-response data may be excellent, but Marine Drugs is built around chemically defined marine compounds, and an undefined extract has no compound for a structural-chemistry reviewer to evaluate.

The testable version of this failure: for every activity claim in your paper, ask whether you can point to a specific molecule with a structure and a name. If the answer is "the activity is in this fraction," the package is not ready for this journal, and the fix is either to complete the isolation and characterization or to redirect the extract-level work to a journal that accepts it.

Check whether your Marine Drugs compounds are defined enough for the journal's scope

A structure proposed without the full NMR and HRMS dataset

The pattern: a drawing the reviewer cannot verify. The second pattern shows up at the reviewer stage: a new structure is drawn, but the supporting spectroscopic data are incomplete.

We repeatedly see papers with a 1H spectrum but no 13C or 2D NMR, an HRMS value quoted in the text but no spectrum in the supplement, an assigned absolute configuration with no ECD, X-ray, or computational support, or NMR tables that do not follow the ACS data-presentation standard.

Because marine natural products are structurally complex and the field's own structure-revision record is well documented, reviewers expect to verify the assignment from the raw data, and they will not take a structure on the strength of a drawing. The testable version: for each new compound, confirm the supplement contains original 1H, 13C, and 2D NMR plus the HRMS spectrum, purity confirmation, and the specific evidence behind any stereochemical assignment.

Check whether your Marine Drugs structure elucidation is fully supported before review

A "marine" source with no marine-specific significance

The pattern: marine as a label, not a reason. The third pattern is a study where the marine origin is a label rather than a reason. The compound was isolated from a marine organism, but the chemistry, the pharmacology, and the discussion would read identically if the source were terrestrial.

Marine Drugs exists because marine habitats produce distinctive chemistry, so a paper that treats the marine origin as incidental is a scope-fit risk even when the compound is fully characterized. The testable version: read your own introduction and discussion and ask whether the word "marine" is doing any work.

If you could swap in a soil bacterium or a land plant and change nothing, the framing is too thin, and the fix is to make the marine context, the ecological or biosynthetic angle, or the marine-specific pharmacology explicit.

Scope drift into general natural products or general pharmacology

The fourth pattern is scope drift, and it is the one authors miss most often because the work is genuinely good. The manuscript is a competent natural-products or pharmacology study that happens to touch a marine organism, but its center of gravity is general phytochemistry, general medicinal chemistry, or a pharmacological mechanism with no marine-specific element. The section editor cannot place it, and the paper is redirected to a general-chemistry venue.

The testable version: name the Marine Drugs section your paper targets, then check whether your abstract and results actually deliver on that section's remit. If you cannot name the section, or if the natural fit is a general journal, the drift is real and the framing needs to be rebuilt around the marine-chemistry question.

Each of these is something you can check against your own draft before you commit the submission. This guide tells you what Marine Drugs editors look for; the review tells you whether YOUR paper passes the pre-check and the structural-chemistry review before you upload. We have reviewed manuscripts targeting marine natural-products and natural-products chemistry journals, including Marine Drugs and its peers.

Paid Manusights reviews include a 60-day money-back guarantee, and we do not train models on submitted manuscripts. Run a Marine Drugs submission package check to see whether your compound definition, spectroscopic dataset, and marine framing will clear MDPI's pre-check.

Marine Drugs reports a median first decision near 13.6 days and median acceptance-to-publication near 1.9 days. Treat these as planning ranges, not promises: structure-elucidation papers can run longer because the editor has to find a reviewer who can actually check the spectra.

• Day 0: Submission via SuSy. The portal accepts the package and routes it to the section editor for pre-check.

• Days 1 to 3: Editorial pre-check. The editor screens scope fit, marine relevance, compound definition, ethics and sourcing completeness, and integrity and plagiarism checks.

The fastest returns happen here, before any reviewer is invited.

• Days 3 to 7: Reviewer invitation. Manuscripts that pass pre-check enter single-blind reviewer search, typically targeting two or more reviewers, with structure-elucidation papers needing a referee who can verify the NMR and HRMS assignments.

• Days 7 to 14: Peer review and first decision. Reviewer reports return and the editor issues the first decision, with a median near 13.6 days from submission.

Major or minor revision is the most common outcome for papers that clear pre-check, and revision requests on structural papers usually center on missing spectra or stereochemical evidence.

• Days 14 to 30: Revision and acceptance. Revisions are usually requested on a short clock; supplying the missing spectra or the requested configuration evidence and resubmitting commonly lands acceptance inside a few weeks for complete, in-scope packages.

• **Days 30 to 33:

Production and publication.** Acceptance to publication runs near 1.9 days at median, so the slow part of the calendar is reviewer search and revision, not production.

This guide was researched and built from primary sources: the sources we checked include the Marine Drugs Instructions for Authors, the journal's aims-and-scope and sections pages, the MDPI APC page, MDPI's research and publication ethics policy, and Manusights pre-submission review patterns from marine natural-products manuscripts deciding between Marine Drugs and peer journals. We compared current MDPI author guidance with recent Manusights review patterns from authors weighing Marine Drugs, Journal of Natural Products, Phytochemistry, Frontiers in Marine Science, and Molecules. Last reviewed by the Manusights chemistry editorial team on 2026-06-07.

Source limitations: MDPI can update APC, abstract caps, spectroscopic-data requirements, and editorial-process numbers after this review date, so verify final administrative details against the official Marine Drugs author pages before upload. Median timelines are reported by the journal and vary by subfield, and structure-elucidation papers tend to run longer than the median. Use this guide for the decision the official instructions cannot answer: whether your compound definition, spectroscopic dataset, and marine framing are ready for the MDPI pre-check and the structural-chemistry review.

• Marine Drugs journal profile
• Journal of Natural Products submission guide
• Molecules submission guide
• Best natural products journals
• Molecules journal metrics

Before you upload, run your manuscript through a Marine Drugs submission readiness check to catch the compound-definition, structure-elucidation, and scope-drift gaps the MDPI pre-check and reviewers filter for. The check is free to run (/ai-review) and takes a single upload.